KymcoForum.com
Scooters - 50cc => zx50 => Topic started by: rigpa on August 04, 2010, 08:04:24 PM
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Hey All,
I have 18,000 miles on my zx 50 and she's going slower up hills, way slower. i've new rollers and a new exhaust. i'm thinking the compression is getting worse. my local shop suggested i just get a whole new engine and have them put it in. what do ya'll think of that. what are the options?
thanks,
Linda
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I think I would get a second opinion , from another shop . Good luck .
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..RUN!! AWAY from that shop and never go back!!!
..try a new plug first...cpl bucks, and it could be your problem..
..clean or replace your air filter..
..could also be that you need a new drive belt..
..could also be that you variator rollers are worn out...
..these four things are the most likely culprits..
..post back and let us know what you find!!
..oh, and Welcome to th' Forum!!!
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believe in the word........ RUN, then try those things, if still not correct, then a compession test.... i just turned 20,000km on mine, NEVER ran better...i have put rings in tho..myself to boot.. WELCOME TO THE FORUM.....need some zxs in the house....lmao
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Ha! There is the kit option,Kinda cheaper than new! Ha! Make it run the best it can first! Lots "O" miles left in that motor. Good luck and welcome to the forum!
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hey all,
thanks for the welcomes and the suggestions. i forgot to mention i also have new spark plug, and belt. i think it's a compression thing. does that indicate worn piston rings. i've never tore down or rebuilt and engine. thanks. i love my zx. had her for 4-5 years now.
Linda
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I would still verify the compression diagnosis at another shop . Older 2 strokes often have a problem with carbon build up in the exhaust which can cause loss of power , using full synthetic oil and one oz per gal of sea foam additive in the gas can help prevent this . Good luck .
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...yup, what juice said...could be compression, and sea foam works wonders at removing carbon build-up...
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if you have changed belt, rollers, plug, exhaust.......what exhaust did you use?? are you running stock air box?? did you rejet carb?..where are you located at, if i may ask?.. a compression tester is pretty cheap at harbor freight(alot of us shop there..lmao)...warm her up real good first....you should read 100+psi..(mind you,mine only reads 95)..have you changed the contra spring yet?? the rings are pretty easy to change..may take a couple hrs the first time tho(saves big labor cost)..let us know the results.....good luck, i am still learning the zx myself but am glad to try and help anyway that i can....
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..i got my tester at advance auto...around 40 bucks..
..they have a cheaper kit, but i got the one with all the accesories..
..still outta check those rollers at 18,000 km/miles...
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they are suppose to have been changed word...
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..oops..missed that in th first post..
..where did my memory go??
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you are still a baaaaaaaad man, word!!!.. ;) ;D ;D ;D
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..it's either th hippie grass or th bud lights...
..i dunno...
;D
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hmm?!?...could be the combonation.. ;) ;D just neeeeever know... ;D
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okay, i got a compression tester. looks like you have to put the spark plug attachment into the spark plug hole before the compression gage hose snaps on. I haven't actually yet done that--this weekend i will, but i took it out of the package and couldn't get the hose to snap onto the part that goes into the plug hole. At any rate, I have some questions about new rings. Do the new rings come at the prescribed end gap measurements? If they are too big, how do you make them smaller, and vice versa? thanks.
Linda
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hey rigpa/linda...you may need a dab of lubricant on the end for easier snapping, should snap on pretty easy tho.. the rings come already gapped from the factory..idk about adjusting ring gap,maybe somebody will have an idea there.. a few of the zx ppl have taken the summer off i think..lmao if to big, they need changing.it will allow air to seep into case, losing compression. i took my engine apart to look inside over last weekend, alls well inside my motor, should clean cyl again tho...lmao...hope any of this helps...post back and let us know whats happening....good luck...
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If you can get that spark plug hole piece on the hose first, then can always spin the whole thing round and round as you're threading it into hole. I've had to do that at times. Just make sure to tighten it well. 8 or 10 kicks should give you the reading then.
New rings usually are real close on end gap. If too big it prob means your cylinder walls are worn. In fact that's one way of diagnosing a worn cylinder. But the new rings might still help. Don't think there's any way to close up a gap that's too big.
If too small then the ends of the new ring can be VERY delicately filed with like a jewlers file or fine nail file. Would have to have like a jewlers vise too. Rings are made of very brittle carbon and will chip easily so must be patient and delicate. You prob won't have to do this.
When dropping the cylinder back in place, you gotta squeeze the rings one at a time and feed em up into cylinder. Can do this by hand. A ring compressor is almost more difficult to use than the hand method on these small engines.
Main thing is to clean the ring seats in the piston well to clean out old carbon deposits. Use cheap jewlers screwdrivers from Wal-mart/hardware store, small knife, etc. Careful not to nick piston outer surface too much. ;)
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after 11.000 miles on my agillity I got my motor re bulit it seams to be great and running good.
I would just rebult what you got you should be able to get another 18 out of it. just get new rings
a get it board out a little. and a good tune up and you should be good.
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By the way, there're other things to do/watch for in a ring job. You might need a cylinder base gasket and head gasket. ZX guys, does she? And some gasket sealer. Something to scrape old gasket material off. A plastic knife for instance? Some solvent of some kind to remove old sealer. WD-40 prob work for that.
Stuff rag into crankcase opening to keep debris from falling in there while working -- very important not to let anything at all drop in there.
It may be easier to take piston off for the cleaning of the ring seats, though not absolutely necessary.
When you get just the head off, turn engine till piston is way down low, then feel the cylinder wall all around with fingers up and down especially within an inch or so of the top. If it's worn badly, you can feel a bit of a ridge around the top at the level above where rings never travel.
Then check end gap on new rings by gently squeezing them down into cylinder well down in. Must try to have the ring sitting perfectly level in the cylinder. Oil the walls first. Then can measure or judge the end gap. If you've already got old rings off, you can judge their end gap in comparison to the new ones, though if you get that far might as well just put the new ones on.
Take the opportunity to inspect the head for carbon deposits and clean if needs it too. Also check if piston can wiggle on it's wrist pin. Good time to replace that too if needed. Not hard.
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wow guys and gals this is great stuff. thanks. yeah i was wondering if i need a new cylinder gasket. i don't know if they are the rubber kind or what? also, what do you clean off the carbon with, what kind of solvent?
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Scraping or wire brushing is main way. Careful not to scrape or brush over gasket sealing surfaces.
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Very good write up Hoolander. With regard to gaskets, the base gasket, at the bottom of the cylinder is paper, if you cut one yourself make sure you use material of the correct thickness. When buying rings you usually get piston, rings, wrist pin, circlips, head gasket for about $30 on ebay. If you are concerned about the bore, you can buy a cylinder hone from an auto parts store. If you like this sort of thing you will find it to be fun and a good way to learn. To top it all off a sense of satisfaction when it all goes right. Good luck and enjoy your scooter. Go the ZX. :-)
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i'm reading the zx 50 service manual for piston ring removal and installation. it's saying something about an expander. when installing new rings it says first install the expander in the 2nd ring. is an expander an installation tool. if i'm not using one would it just mean to install the 2nd ring in the 2nd ring groove first. is this the compression ring? also, if i need to rebore the bore or re hone it, won't i have to get a larger piston. i mean how do you allow for the larger cylinder? thanks.
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The ring expander is a type of shim that goes in the groove behind the ring. Both rings are compression rings. If you run a hone through the cylinder you won't need a larger piston, if you bore it out you will.
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okay, does the expander just pop in or is it hard to install like the rings. can i just reuse the old expander?
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You should get a new one with the new rings. It is easy to fit.
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yep, and thats how its done.....
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G'day rigpa, I have taken a pic of a piston kit I have for my scoot, it is a ZX50 but it has a 50mm cylinder kit, (82cc).
The stock piston is 39mm.
One pic shows the contents of the kit, which is 1 piston, 1 wrist pin, two circlips for the wrist pin, 2 rings and one ring expander.
In the other pic you can see the ring expander is the wavy looking item, this is wrapped around the piston in the lower ring groove, unlike the rings this is very flexible and there is no risk of damaging it. When installing the ring to this groove, make sure the expander ends are butted to the pin in the groove, not overlapped. I reckon there was a head gasket with the kit but I have already used it, hence it is not in the pic. I hope this helps.
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Thanks, that is helpful. You see the ends of the piston rings and how they are not flat, the one edge seems to jut out. Why is that? Especially if you have to grind some off to get the proper gap. Would you not be grinding that shape away from the rings?
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Yes, in each ring groove there is a locating pin, the ring gaps line up with it and it prevents the ring from rotating on the piston during service. If you filed enough off the ring ends you would then have to file that notch back, with a littld care and patience all will be fine. I think it would be unusal to need to do this though, the rings should be within tolerance.
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i'm looking online for replacement rings, etc. is the cylinder aluminum, and is it horizontal. will any rings for a 39mm piston work?
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No, the zx has a vertical, cast iron cylinder. I think it would be best to get piston and rings as a set.
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a local kymco/kawasaki shop keeps them in stock for around $32.00..i believe thats what it was after taxes..for me, oem parts are easier there at dal-kawa......stadiumyamaha.com has alot of oem kymco parts..either site should be all you need..dont sweat the gaps, they are ready from the factory(i guess you have the one in a mill shot of getting a bad part tho)..
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i checked in with stadium. they said their rings don't come with instructions. is there a certain side that goes up/down. will it matter which ring i put on which groove and if so how will i know? check against the ones already on?
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yeah the rings are marked when you take them out of the box....a T for the top, a B for the bottom. put the letter facing up. its a small letter of course. the rings can only go in "thier" slot on the zx. you can see the difference when you have the piston open where you can see it.
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If one actually needed to file the ends of the rings, one should never file the notched area since that already fits the piston perfectly. Just the part that juts out beyond the notch. Again, in your situation, it'd be almost impossible you'd have to do that.
Did you do your compression check?
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I apologize I have not done the compression test yet. Too exhausted from painting the house and pulling weeds, but i have run 3 tanks of gas with some sea foam and it's made a good difference. I will do it soon. Meanwhile all the discussion about the piston and it's rings has been enormously helpful.
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we gotta help each other.. ;D ;) everybody wants to ride and go fast :D ;)
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The first time you do a job like that, (replacing piston/rings), it can be daunting, but once you have done it you see it is not that dificult. I have had mine apart so many times now, I have lost count.
A recent job I had on my car was to remove the complete instrument panel, a very scary proposition, but I couldn't afford to have the dealer do it so I set to and got the job done. I guess what I am trying to say is have a go.
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so, i tried to hook up the compression gage to the spark plug cylinder hole last night, and there simply wasn't enough room to get the gage in the hole. what else do i have to remove. i removed the seat, and side panel, but it looks like i might have to take the muffler and cylinder cover off? i've changed the spark plug plenty of times, but as you know, there's not much wiggle room on the zx 50.
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Not familiar with it. Come on ZX guys.
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Try removing the nut at the bottem of the shock mount. Than lift the frame of the bike from the back. This should give you a bit more room.
Alot of compression guages have a flex hose may need another type of fitting if this don't work.
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it is very tight in there, but the ones i have used, do work, just have to play and twist whole thing holding the gage it self...you may be able to let the air out of rear tire to get a bit of room....... guess you could lossen the inner fender/oil tank to give extra room..hope this helps...
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So, Art, you saying take off both bottom rear shock mounts so the swing arm/engine will point more up? Sounds reasonable. Then would you just leave scoot on center stand and let wheel drop to the ground?
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My gauge has a flexible hose. It is hard to get at. I take off the seat and met-in box, then screw in the fitting by twisting the hose by reaching under the body plastic and guiding with my right hand. If you want to remove the engine shroud, you can without removing the exhaust but it takes a lot of twisting and is a big pain. How did you go about removing the side panel? I have only taken the whole lot off as one piece.
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After much weirdness with the parts dept at stadium yamaha, i finally have my rings, circlips, and head gasket. My order came with a little black o-ring, but the parts guy doesn't seem to know where that goes. Does anyone know if that fits in the groove on the head gasket?
Also, I'm going to deglaze my cylinder bore with a scotchbrite pad. Does it matter how i clean it in terms of going up and down or sideways with the pad? I also read somewhere that you can use oven cleaner to deglaze. Anyone think this is good/bad? Thanks.
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No, nothing goes im the groove of the head gasket, that squashes flat when you torque down the head. For the bore, I would use a hone, mine was only $20. You will be on your way in no time. You dont need to remove the body but it does make it easier.
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Scotch Brite should be fine. Move it mostly at an angle -- neither straight up and down nor sideways. Whatever deglazer solvent you use, be sure not to breath in a lot of it. Have a fan blowing across your work area and have door or windows open. Oven cleaner requires gloves usually. After deglazing, a thorough spraying with WD-40 to get the oven cleaner off and flush debris out of all ports. Finally, wipe fresh motor oil or two stroke oil all over inside the bore.
Maybe you'll find out where that o-ring goes when you take it apart. ;D
Did you get a new piston wrist pin?
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i got two new wrist pins. anything special about installing these?
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i haven't yet done the compression test. I will when i start to tear into the cylinder, well b4 actually. I'm suspecting i have at least a poor, worn oil ring. the scoot's been consuming oil and spitting it for a couple of years now. plus once or twice the oil pump feed that goes into the carb came out and it stopped running/seized. from what i've been reading 2 strokes get a lot of carbon build up. i don't think the oil leaking helps.
one day last week, while going up my one very extended hill on my commute, let's say i'm wot for 10-15 seconds going very slowly due to whatever, poor compression, carbon blockage in the muffler, exhaust port, the scooter started to die, so i backed off the throttle and hit it again and she regained her slow but steady pace. any ideas why this might have happened?
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well my scoot drinks the oil.. :D i get around 13-15 tanks of gas per bottle.... yeah, you may have carbon build up.. i recently discovered my nasty buildup.. seafoam does seem to have really helped this very quickly....you really need to test things......... the carb may need some cleaning......as i recently learned, check ALL the gaskets for leaks while at it.. ..
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seafoam does seem to have really helped this very quickly
..it only gets better...
..keep using it..i have, and my a50s exhaust just keeps on opening up...
..i've had to up jet 3 times...
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Strange you should get 2 wrist pins. Maybe one is a couple thousandths larger than the other just in case there is wear inside conn rod? You can try to test fit both through conn rod.
Well, you just don't want to force the piston back and forth too much when removing/installing it. Take out the circlips which hold in in place with needlenose pliars. They'll deform easily so hope you got new ones with your parts. If not, can bend em back into shape but better to have new ones. Once they're out, sometimes the wrist pin will just slide right out with a little pressure. Sometimes have to bang on it. If so, back up behind piston with rags or small pieces of wood. Same for new one going in. Oil it and it's races in piston and conn rod first.
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Just a thought: Check for inscribed writing/numbers on the ends of those wrist pins. Maybe size info there?
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Early zx had 10mm wrist pin and later had12mm pin. They may have given you one of each? But the pin would have to fit the piston.
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sid is right..the 01-02 models have a weaker 10mm ...the 03-04+ went to the stronger 12mm.
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Thanks batman, I wasnt sure of the year, I was thinking 04.
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that little white plastic thing underneath the gas tank is the fuel filter right? how does one clean those?
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The inline filter is usually disposable. The screen in the tank is reusable, to get to this one you need to drain the fuel from the tank and remove the fuel cock. Be aware there is an o-ring in there too.
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Hey rigpa, how did you go removing thd body panels? Was that guide any good?
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next week i plan the big ring replacement and cylinder cleaning. i have some time off, which i'm sure i'll need. i'm going to print out this entire thread as a helpful guide along the way. thanks and i'll let you know how it went/goes.
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Good luck, you will be surprised at how easy it will be. When you put your cylinder back on, make sure you have the rings lined up with the pins in the piston, use a torque wrench if you can get hold of one and make sure your gasket faces are clean to ensure a good seal.
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Well..........i have taken off the cylinder and piston. Both are badly scored from the seize a couple years back when the oil connector inlet came off (the thing that feeds oil into the carb). Plus the oil expander ring that goes in the bottom most piston ring groove, was broken. I peeled half of it out, i think the rest is still in the groove. I gotta say, it was hard work getting to this point. My biggest problem was not being able to easily get to that last engine cover bolt. I tried to take the air box off for more room but one of the bolts is stripped. I eventually got it off anyway. From there it was pretty easy, although i did have to have help removing the circlips. So, now i've got to get a new cylinder and piston. that's what's happening. thanks for all your help.
linda
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also, what do people think if i just get the cylinder new and reuse the existing cylinder head, with carbon cleaned, of course. is this a bad idea? would save some bucks but worried about the fit.
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If you are going with the same size, that head will be fine. Do you really need a new cylinder? Can your existing one be cleaned up and reused? I thought you got the piston kit? Can you post a pic of your cylinder bore so we can see the damage. When setting up my cylinder I had a lot of trouble and seized gt a few times, but it was still useable.
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im with sid...clean the cyl up and try to use it,just because piston has marks, maybe able to clean the piston, new piston,rings could be a good idea..i had to put some in at 14000...be carefull tho, you could accidently bore it out more.... cyl should be ok since you were riding it too......
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Yes, please don't jump to the conclusion you need a new one. You can have the old one bored to the first oversize and buy first oversize piston kit. Check for availability of this first of course. I don't know if they even make oversize for these scooters but they're usually made for every other kind of engine I've ever seen. Call a local machine shop or two and ask if they do boring. Many do and it'll be cheaper than a new cylinder. Perhaps faster than ordering a new one as well.
They will be able to advise you on the condition of your current cylinder before boring. That is, they may suggest you just have it honed slightly and, if it's measurements are still in spec, it's good. If not, or if honing doesn't get rid of the scratches, they can then bore it.
You'll have to supply them with the specs for the cylinder from the shop manual for your scooter -- usually available on line for free.
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ZX guys, am I right? Or does it have like a coated bore which can't be bored?
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I do balieve you are correct Hoolander, I don't know of any oversize specifically, a replacement cylinder is available for a very low price. Unless the damage is extensive I would clean it up and use it with the new rings while looking for a new one if you so desire. If the piston is scored you can clean it up with 600 emory cloth or wet/dry sand paper using a little WD40. If doing this rub around the piston, not up and down. Good luck and let us know how you go with it. Any chance of some pics of the inside of the bore?
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yeah, thats my next project i hope. ;) oversize piston kit.....yeah, pro-x.com has the oversize kits for the zx i know....around the same price as getting a stock piston/rings for me from the localISH dealer.. ;) ............i would venture to say the cyl. should be ok......
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Batman to the rescue, good to know that. I hadn't looked myself, went to a 50mm bore straight up.
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Hi ya'll. okay. i'll get some sandpaper and see if i can clean the piston and the cylinder. i'm leary about boring to oversize since i've already ordered the piston rings. i guess i could always return them but i'll see what some mechanics say about current condition of piston. it would sure save money and i'd be on the road in no time. thanks.
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The piston kit is only about $25, it will have all you need. If you go easy on the bore you will be ok, the piston wont take much to clean. Just to step back a little, when removing the circlips, pack a rag over the crankcase opening to prevent anything from falling into the crankcase.
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here is a pic of the piston striations.
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here are the cylinder striations.
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so what do ya'll think? are they goners? i sanded the piston ring a bit, but i can still feel the grooves.
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Yeah, if you can feel those gouges it's probably best to get all new. They look pretty deep.
Before you run the rebuilt top end, check your oil injection system top to bottom. Make sure no blockages or leaks in the lines, tank, ect. No old goopy gunk in the lines/tank.
Too bad -- we were all hoping it'd be less serious. :(
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Yes, I think it would be worth getting all new if you can. If you look around, you can find replacement kits for a reasonable price. I am not sure, but I think I saw $60 kits on ebay when I was looking for an upgrade kit for my scoot. Good luck.
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so what do ya'll think? are they goners?
..oh yeah...they're gone.....
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Here is a link to a replacement kit on ebay.
http://cgi.ebay.com/ebaymotors/Honda-DIO-50cc-replacement-cylinder-kit-_W0QQcmdZViewItemQQhashZitem35aca8373aQQitemZ230529972026QQptZMotorcyclesQ5fPartsQ5fAccessories (http://cgi.ebay.com/ebaymotors/Honda-DIO-50cc-replacement-cylinder-kit-_W0QQcmdZViewItemQQhashZitem35aca8373aQQitemZ230529972026QQptZMotorcyclesQ5fPartsQ5fAccessories)
It is advertised as Honda Dio, which is what the kymco ZX50 is a clone of.
Did you end up getting your piston kit?
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sidthesloth, you have totally outdone yourself. i'm not seeing the sloth in sid. the ebay kit is AWESOME. i did get the rings and the gaskets already, but not the piston and the cylinder. This will save me a lot of money. thank you thank you!
linda
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I also saw one that was in California, it was oem, I think it was about $35 but $57 shipping. If you look around you should be able to find a good deal. If you can get yourself a nex kit on the way, I would clean up the piston and barrel and put it back together with the new rings and run it until the new kit turns up. You might be surprised. Good practice to.
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i went ahead and ordered the ebay kit. how is it that there is such a price difference between this one and the one from the shop?
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Middle man makes money, lots of it. A stroker crankshaft from Ruima, sold by Daywot, $189 on sale, from autotech335 $78+$32 shipping.
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so i got the new cylinder, rings, piston, gaskets from ebay. I went ahead a put the rings in. it looks like the fatter ring goes in the second ring groove based on the ones i took out of the old piston. but was wondering:
1.) if there's a top and bottom of each ring. i think the number 39 was printed on one side of each ring and i installed them with the number facing up.
2.) do i need to put gasket sealer on both the engine block and the cylinder or just the cylinder.
3.) the head gasket has two distinct sides and i'm not sure how it gets installed. one side has a depression and an embossed ring like groove. the other side not so much. i can't tell from the old head gasket, cuz it was flat as a pancake when it came out.
4.) circlips are killing me. i go online for how they are installed and see answers, but do they actually have to fit around that piston bar thingy that connects the piston to the crank arm or do they just abut that bar?
as always, thanks a million
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Good to hear you are on your way, if you are going to use a gasket sealant, use it on both sides of the gasket, cylinder and crankcase. The head gasket is embossed for better sealing, I am not sure which way it goes, i don't know if it matters, but I put the gasket so the inside angle is down, maybe Hoolander can help with this one.
Once you get the first circlip in, push the wrist pin in as far as it will go, making sure it goes through the wrist pin bearing, this should leave the remaining groove clear to install the remaining circlip. before you put the wrist pin bearing in, lubricate it with 2 stroke oil. long nose pliers will help to install the circlips. The circlip abuts the wrist pin.
Yes I believe the side with the writing or numbers stamped on the ring goes upper most. The 39 would be the bore size, 39mm.
Put the first circlip in with the piston out of the engine, when installing the second one, make sure you cover the opening to the crankcase to prevent it from falling in there if you drop it, this can happen easier than you might realise.
Good luck, now you can enjoy putting it all back together, knowing it is almost a new engine.
If you are not certain your oil pump is working properly, you can put 75-100mls. of 2 stroke oil in your fuel tank to guarantee lubrication of your cylinder until you can get the pump proven to be working.
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..awesome....
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IS there a cylinder base gasket on these? rigpa hasn't mentioned having one, I don't think. Sorry, don't know which way head gasket goes.
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Yes there is a base gasket, though I wouldn't use a sealant unless I suspected a leak, mainly because I would be expecting to pull it apart again. :) With the head gasket, I don't think it really matters, it gets squashed anyway.
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hello and thanks. so i don't need to use gasket sealer at all?
sid, are you saying put the first circlip in and then install the cylinder and then put the 2nd circlip in?
linda
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i got one more issue:
when i was trying to remove the cylinder i thought it would help if i removed the air filter housing for better access to the cylinder cover bolts. well, i got the air filter hose off the carb, but that was it due to a stripped bolt. Now i can't get the damn thing back on. I've loosened the hoseclamp but the issue is actually getting the hose back onto the carb--it won't seem to go on. i was wondering if i ran a hair dryer over it for a minute or two to make the plastic more malleable if that would help? thoughts?
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Put the first circlip in the piston, then put the wrist pin bearing in the conrod, then install the piston and wrist pin then the last circlip. If the gasket surfaces are clean and undamaged then you won't need a sealant. But I would prefer to hear from others on this though, I wouldn't want to give you bad advice.
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Just a dab of oil inside the hose or on the outside of the connector might be safer and easier . Good luck .
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Yep, that's what Sid is saying. ;)
The hairdryer idea is a good one in my opinion. Juice's advice good too. Do both.
Either way on the gasket sealant. Some sealants start to harden up so quick there's hardly enough time to apply it and then get piston into cylinder, head on, bolts in and tightened before it's too hard already. Why not go without it this time.
Main thing is tighten all head bolts as evenly as possible. It'd be nice to have a torque wrench but can tighten by feel.
Hey ZX guys (Sid) should the head bolts be re-tightened slightly after a warm up --cool down?
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Yes, I think so, after a warm up and cool down, just check the bolts, 10lb/ft I think is the correct torque, eveness is the most important thing. Hair dryer is the best for those awkward airbox pipes, I recall a nightmare with a particular GPX, but, she was worth it. :)
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rock-n-roll, looks like my saturday is spoken for. so, after i get the scoot back together, should i start her up and take her for a spin, let her cool down and tighten the bolts and then put those engine covers back on. in other words, no problem if i don't have those covers on right away?
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Yes, put the shrouds back on, they guide the air over the engine for cooling. When you get the engine back together, run it for a few minutes, let it cool, then check the bolts and you should be right.
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thanks. i'll give it a go.
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Good luck, if anything gives you any hassle, just be patient and you will be fine.
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sorry i hadnt been around.... congrats..... sid is the man... ;)
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Good News! She's done. I got the circlips in myself after practicing on the old piston. Geez, is that hard. Circlips were flying all over the place. I did have to take the scoot a half block down the street to the guy who sells Motofinos (I know, I know) and have him install the the cylinder. Couldn't figure out how to keep the rings in place and squeeze them and put the cylinder over them all at the same time.
So, how do i break in this new cylinder?
also have some electrical/lighting issues, but i'll make a new thread after searching to see if it's already been talked about or no.
thanks for all your help. it's wonderful!
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i got one more question, i'll ask here. it's about the cdi unit. the holder was rubber and it's shot. therefore, the cdi unit just hangs there. sometimes i stuff it in wherever, usually sitting on the cylinder cover. any thoughts about a permanent fix?
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If you can still put it in the 'pouch', for want of a better word, use cable ties to strap it to the original bracket.
Congrats on your engine. I won't advise on breaking in the new cylinder, I just ran mine as usual, but I think you aresupposed to run about half to three quarter throttle. Again, congratultions, now you can enjoy your scoot again.
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thanks, sid. pouch is the perfect word and the pouch is sitting on my front porch. zip ties sound good. i'm pretty relieved to have the scooter back running. now i gotta fix my left tail light bulb being out. i hope i just need a new bulb.
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Yep, is easy enough to get to, when you take off the section below the tail light, I think it is just two screws to remove the tail light. Replace both bulbs while you are there, the other one will only last a couple more weeks. lol, ask me how I know.:)
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how do you know that, sid?
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I replaced the left one. Then about a week or two later, I replaced the right one. :), sid the slow learner sloth.
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are these bulbs specialty parts, or can i get them from an auto parts store? if i can, what am i looking for? thanks.
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They are a standard tail/brake light bulb, 12volt 5/21watts dual fillament bulb.
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I always try to take the old bulb with me to the parts store , that seems to help . Good luck .
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the number of the bulb is a 1157..dual filiment as sid said.. (a single is 1156)... congrats on the engine. when i had piston/rings done, i was told to be easy for 2 tanks of gas, but at the same time was told thats what 2ts are made for and run wide open as soon as repaired..i did go easy for ALMOST 2 tanks of gas. ::) ;D
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that does seem like a long time not to run WOT!
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Good News! She's done.
You did it! Way To Go! Congratulations, Linda!!!
Glad you'll be able to enjoy your scoot again. :)
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it went pretty fast since she is my daily ride. :D it dam sure was hard not to run wot all the time..... ::) i cheated some tho... ;D ;)
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there is a rubber hose that comes off the carburetor and runs along the variator cover and then rests in a little metal grommetty thing that screws into one of the air filter's bolt holes. this got loose during the work that i did and fell off yesterday. i recovered it but haven't yet put it back on. where does it go and what does it do?
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Thanks, Rianna!
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The question on all our minds is -- is it running yet and if so, how does it do? ;) Sorry, don't know about that hose.
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oh yeah. She's running. I wanna say running great, but i can't put too much torque on her yet. yesterday after work, i took the scoot to Petsmart to get some cat food. That's like a 7 minute ride. When I came out, she started up just fine but then i had to wait for cars and people before i could go and she died. Couldn't get her started again, this isn't an unusual situation when i have to idle after just starting. I think the plug gets flooded. anyway, that's when i started kickstarting and dislodged that hose. then i was worried that the hose was critical to starting the scoot, but after 5 or so minutes, she started. Still need to get that hose hooked up. I'm thinking it's either the float bowl drain hose, or some kind of vacuum hose, which probably is very critical.
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Hi rigpa, that hose would be the vent from the carb, it is not critical but do put it back on to keep any dust out of the carb and to direct any fumes and residue away from the engine. That hard starting is what brought me to this forum in the first place. I had found that it was hard to start after it had been sitting for ten minutes or more. I have recently put a TZR50 cdi on my scoot and it does start a lot easier. I am not saying this is the problem with yours, but something to think about in the future.
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Glad to hear she's running! :) Congratulations on your first and a sucessful top end job! Did you make sure your oil injection is working good? No gunk in lines, tank, pump?
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uh....no i didn't. suggestions for how?
also, was reading on this forum under a carb post, that someone else had their oil inlet hose fall out of the carb. it was suggested that they use a bit of locktite. does one pull the inlet hose and put locktite on it and then put it back in or just have the hose in the carb and put it around on the outside? i'm sure that's how my piston seized, when my hose came out because i remember it stopped running. that was one or two years ago. i don't want that to ever happen again.
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Without going looking for the thread, I think I remember that one, the little hose fitting came out of the carby. When putting it back in, clean it up to remove any oil and do the same with the orifice in the carb, put some locktite on the outside of the fitting and push it into the orifice and allow the locktite to set. Make sure that the fitting is pointing in the correct direction so as not to put any stress on the hose. According to the manual, the oil injection line goes into the inlet manifold, but in fact, the later ones went into the side of the carb, do you know which one yours has?
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mine goes into the carb
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Very good Sid. ;) Just use a very tiny amount of locktite and for God's sake, don't let any go inside!
I've heard of the oil tank getting a layer of junk/gunk build up in the bottom and same thing can happen in the hose, blocking off the hose so, I'd take off the hose there and just see if oil flows well. Blow through the hose while it's off to make sure it's not gunked up too.
As well, look in where it goes into the carb. Shouldn't be gunked up there either.
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By the way, we're talking about locktiting the metal inlet into the carb -- not the rubber hose itself.
If the hose end looks expanded, you can cut just a little off the hose and push back on. Same at the oil tank end. If hose is too short for that, get a new piece at hardware store or auto store.
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I can't say for sure, but I think there might be a filter/screen in the hose just below the tank.
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update on the scoot: took her out yesterday, full throttle, nice long ride, etc. got a lot of boost on the flats, like low 40s. not as impressed as i wanted to be on the hills though. i'm wondering if when i first got the scoot, i was just so excited that i didn't notice its puny pull uphill.
one question--is it possible to put the cylinder over the piston when the rings are not aligned properly to abut those pins in the piston. the reason i ask, is because i didn't see the guy who installed the cylinder do this work. it was just finished when i picked up the scooter.
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good news...wooo hooo.... ;D yeah, they kindof have a puny pull...what are you considering puny tho?? that could be your rollers.. ....well yeah, they can force it on or pinch the rings where they "lock" inside the piston(no free spring) but it wouldnt run and probably wouldnt start.. i had that issue with mine. or if you put the rings upside down... feel good, its gotta be ok. :D now on to the next mod. :D ;)
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hey hey, took the scoot to work this morning for the first time since the rebuild. so this being my usual route i was able to tell where the power is. It's all there! i have way more power on the straight aways and at least i have the umph going uphill, like she's not gonna give out, she's still with me so to speak, going uphill. i'm very pleased.
i did think about different rollers. i'm running stock, which i believe is 8.5. would 7.5 give more or less umph uphill?
thanks again to everyone who made my scoot nearly whole again. i say nearly cuz i got little odds and end parts like bulbs and screws on order.
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Great! ;D Safe scootin'.
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hey rigpa, great news... yes, you should definately drill a few holes in your exhaust (if stock), and change the rollers.. i would try 7.5...a roller tunning kit will become very handy for you in figuring out any better weight, i learned that much recently.. cant remember all/any of your mods but they will help keep those rpms up. . and then of course, jet that carb with an open air filter. ;)