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Scooters - 50cc => People 50 => Topic started by: wordslinger on June 28, 2010, 10:44:25 PM

Title: ..scoot shuts down..
Post by: wordslinger on June 28, 2010, 10:44:25 PM
..so i was riding home today...not wide open, just kinda throttling back from time to time...

..scoot shuts down...

..won't fire, tries to fire and run, but it just won't ....

..a bud comes by, sees me, stops and we load it in th back of his truck..

..drop it out at home and it fires immediately when i hit the starter button..

..however...there seems to be a "hissing" sound from the carb that i don't ever recall hearing before...

..it'll run..but i don't hear the pop-pop-pop at idle throttle like before...more like pss-pss-pss...

..cracked reed?

..not that I know just how th' f8ck a reed works,  ;D

..  ??? ..

Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 12:57:41 AM
...upon further inspection, and let me give some background..

..i took out the 748-18-28 belt, due to the damages it sustained during my a50 ncy torque drive delima..

..installed, what i thought was the "new" 23100" belt i had, but was actually the belt that was on th' ppl when i bought it...

..mistake...

..because, i had went to 9 grm rollers with the long belt, and they apparently put too much pressure on that old belt...

..snapped three teeth from it, and that's when my scoot died...

..over-revved?? when the belt slipped on the torque driver??

..scoot runs, but with much less oomph...

..reckon i'm gonna get into some two-strokin' experience before i really wanted too...
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 02:33:32 AM
That don't sound good.Whats the plug look like.Try another and cross your fingers.check the compression.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 04:39:01 PM
..plug is dry and a rich brown color...

..put new plug in, with no change..

..i rode it to work today, and it has definately lost some power..

..initial take-off is almost normal, but then engine drops rpms, and the power loss..

..i never attempted to wind it out...
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 07:27:59 PM
Maybe some old filter in the main jet or compression loss comes to mind hope it's a jet.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 08:47:17 PM
..not old filter for sure..i'm runniing a k&n..all that's been eliminated and the carburetor thoroughly cleaned...

..everything was fine until the teeth snapped from the belt...

..then it just died, and would not fire enough to crank and run until it cooled down...

..to check the reeds, i only need to remove the intake manifold, correct??

..are the seals generally re-usuable, or should I wait until i order some to dis-assemble...
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 10:53:37 PM
Ya the intake is easy.Iv'e been lucky on all my scoots as far a re-using gaskets,but theres allways that one!
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 10:56:54 PM
..cool..

..can you think of any reason that a belt dropping teeth would damage the reeds??

..i didn't really hear the engine rev high..but i DO have the hissing noise that is coming from the carb....
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 11:06:20 PM
Thats kinda wierd,Don't see how the two are related,but hay you wanted to look at those reeds any way  ;D performance wize i'd say dirty main,hissing wize reeds or worse.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 11:15:08 PM
...the hissing actually becomes a "whistle" while riding...

..as cars go by, i can hear a distinctive high-pitched whistle rebounding back to me...
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 11:17:59 PM
...and i can still hit over 50 mph, if i let it go...but i'm keeping it held back until i figure this out...

..it's just not the strong beastie it was before the old belt sh** th' bed...

Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 11:22:33 PM
Hmm.guessing at this point,but gets worse when under a load,maybe a toothe stuck in the clutch or bell or is it deffinetly the engine,check those reeds  ??? copression after that,reed stuck in cylinder  ???
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 11:34:53 PM
..imma get me a compression tester tomorrow...i need one for troubleshooting the a50 anyway...

..any specs on a tester that i need to be looking for??...thread size..connections, in general??
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 11:43:04 PM
Bring a spark plug,pretty common size,you want 100+psi so i'm told I think 120 the magic#Did you read my post about the gates belt in your look out world! I think harbor freight has one withh the 3 sizes we lost them all! but there cheap.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 29, 2010, 11:50:24 PM
..yeah, i thot of the spark plug right after i posted that...lol...

..i missed ur post on the othe rthread tho...

..imma try to find what i need local...i need it NOWWWW!!!!
Title: Re: ..scoot shuts down..
Post by: art on June 29, 2010, 11:58:49 PM
We got 3 harbor frieghts within 20 miles.there cheap but get the job done.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 12:00:41 AM
... We got 3 harbor frieghts within 20 miles

..you must live near th' coast...that would make sense...lol..
Title: Re: ..scoot shuts down..
Post by: art on June 30, 2010, 12:14:31 AM
They don't call it portland for nothing!were actually bout an hour and a half from the beach,But we are surrounded by major rivers for transport.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 12:16:50 AM
...duh...i knew you were in portland...i'm stupid...lol..

 :o
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:19:08 AM
Sorry it took so long to find the post slinger, Get a small bottle of Indian Shellac at any auto parts. Your reed cage will have an "o" ring on the engine side, and a peper gasket on top. They work by flexing open on the up stroke to let fuel into the cases, and sealing shut on the down stroke so that mix is forced into the comb. chamber thru the ports. Your oem reeds are stainless steel, and can crack if there is a sudden change in rpms. (IE the belt breaking) Check them asap. If it breaks off it will wind up inside the cases. If you do find a broken reed... Order a set of Boysen carbon fiber blanks at .030-.033 thick. You can easily trace, and cut the blank to fit your cage, and have a quicker response from the throttle, as well as a more stable running top end. Check for a leak around the carb, and cage too before you take it apart. One of those vacuum testers like Shaka made will prove to be you next best friend w/ a 2t. From sitting so long it may have dry seals on the crank.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:28:10 AM
You can easily trace, and cut the blank to fit your cage,


..thanx z....

..and where's the best place to get those blanks..

..carb and intake seals are all gooood...

..would i be leaking any fluid at the crank seal if it were bad?
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:32:46 AM
...here we go baby!!!...

 ;D :o ;D
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:35:53 AM
..vacuum tester...

..compression tester...

..ain't it christmas yet??
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:36:46 AM
Yuo would NOT see any fluid as it is all fuel, and 2t oil in there. It will allow extra air in the case tho leaning out your mix. The reeds can be had at any shop that sells dirt bikes but I get mine from  http://www.rivamotorsports.com/   and I think you can get them from JC Wittney now too
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:38:03 AM
..really..any dirt-bike shop...i need reeds now...lol...coool...
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:38:32 AM
Tell BP you are soooo upset about the spill you cannot think straight. They just may send you some hush money to calm you down...
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:39:38 AM
...and i still got that damned link open ...just stopped posting.....

..i hadda vent...
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:40:55 AM
They will be about 25-30 bucks for the blanks. After you cut them use some devcon epoxy to smear on the cut edges. That will re-seal the raw fiber, and make them last just about forever.
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:42:55 AM
nd make them last just about forever.
\

..yeah,..i like longevity...
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:44:50 AM
I have had them in every 2t I have ever owned. Somewhere around 30ish bikes, and have NEVER had one fail.
Title: Re: ..scoot shuts down..
Post by: art on June 30, 2010, 04:49:20 AM
Ha! keep forgetting about word no 2t ever?Hey zombie did you see my post about the aero 125
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 04:58:36 AM
Yeah man I sent you a pm about it. Should be on the MY MESSAGES. I am definitely interested. Pm me back w/ more info!
Title: Re: ..scoot shuts down..
Post by: art on June 30, 2010, 05:06:05 AM
Cool leaving town tomarrow i'll let you know whats up not realy mine,but posesion is 9/10th of the law!
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 02:50:03 PM
devcon epoxy to smear on the cut edges..

...auto parts store also?
Title: Re: ..scoot shuts down..
Post by: wordslinger on June 30, 2010, 04:15:08 PM
..so i found the Boysen carbon fiber reeds at a local honda shop...

..theyre not blanks, but i'd bet they're larger than what i need, and can cut them to fit..

..anybody say yes??
Title: Re: ..scoot shuts down..
Post by: zombie on June 30, 2010, 07:44:10 PM
Before you buy them check the thickness. You need .030-.033, Any thicker will ruin your idle circuit. Thinner will ruin your top end. It is a balance act just like the cvt. The epoxy can be found almost anywhere. It is the type in the 2 barrel syringe looking thingy. I use the SLOW cure type, and give it over night to cure. Just put a bit on your finger tips, and wipe it over the raw edge. You don't want any extra on the reeds, as it will affect the spring action in them. BE SURE to keep ALL the edges/cuts ROUNDED. You dont want any sharp intersections, as that would be a place for a crack to start. A little emory cloth will round up all the angles. This mod is about equal to doing rollers, as far as results go. Its worth the effort.
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 05, 2010, 05:26:10 PM
..i went ahead and ordered the stock reeds and gaskets from stadium...

..got two new long drive belts coming tomorrow...

..one for each of my ponies...

..yee-haaa!

 ;D
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 15, 2010, 10:47:55 PM
...okay, scoot shut down today, and will not fire...

..getting fuel to the carb, getting spark...

..starter spins the engine over and over and over, but it will not fire...

..spark plug remains dry, and i see nothing at all wet in the cylinder...

..pulled the reed valve, and the reed petals look OKAY!....

..any ideas?

..what am i missing??
Title: Re: ..scoot shuts down..
Post by: Agent Bob on July 15, 2010, 11:34:31 PM
My experience with a hissing sound comes from cars, and that was a vacuum leak.
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 01:40:30 AM
No fuel to carb maybe, did you try starting fluid or some other direct approach.Try that first if you havn't allready.
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 01:55:19 AM
tried it...
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:02:38 AM
Great welcome to 2t's,they do eat plugs,did ya try another,bad spark or not enoupf fuel usualy,compression is also necesary,Did you try to choke it manuely
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:05:59 AM
...yup...tried all that...nothing makes it fire...

..got good spark, but scoot won't fire...
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:13:59 AM
Didn't you have something grounding out in the beginning,disable kill switch maybe,the reeds have not gotten any worse?Plug is dry?gas down the sparkplug whole maybe,should fire if spark is adequate.more stuff in the pipe  ???
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:19:04 AM
...plug is very dry, and so is the combustion chamber...

..even though i got fuel dripping out the filter side of the carb, plug and top side of piston are dry...
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:20:04 AM
...reeds are not cracked...

..plug is medium brown, clean and dry...
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:24:28 AM
That was my next guess piece of reed plocking port,vaper lock maybe,unscrew gas cap  ??? You made me a hero Ha!Yes hair is falling out and going grey.
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:32:28 AM
..now, this is the first time i've ever looked at a reed valve assembly.....


...there is like a black, coating of some sort, that LOOKS like it has been deteriorating from the reed valve assembly...

..the reeds themselves are intact with no cracks or missing sections...i dis-assembled the whole reed valve assembly to check them out..

..and they are made of a fiber material, not stainless steel...and they too, are dry...but i got boo-coo fuel at my carb's intake side...

..even sprayed starting fluid into the carb as i was cranking the starter...

..no fire...

good spark, but no fire...

Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:33:12 AM
You did put fuel in the sparkplug hole and try to fire? The start circuit does bypass the rest of the carb through the choke porting
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:38:35 AM
..no, didn't do that...

..shouldn't my plug and combstn chmbr be flooded if fuel was getting from the carb, by the reeds??...


..aannnd what makes the fuel take that path....
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:41:05 AM
Ya had a good look at mine today same thing,would have to have a large piece of reed to block a port and fiber should get eaten up and spit out if running when it happened,I'd say clean out the choke starting circuit,once again try fuel directly in plug hole,shoud get some sort of fire
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:44:11 AM
...i was running about 50 mph when it shut down...

..is there a timing to the spark that i could check out??

still, i'm wondering why everything is so dry...
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 02:50:40 AM
It's magic Ha!When you put the choke down it opens another port on to the intake side of the carb bypassing the slide and jets I think it straight fuel the vacume line is next in line on the intake side.Once fired it will draw through the airfilter side,this sound like where your backed up there is not enouph vacume to draw from the rest of the carb without fire.
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:53:06 AM
...but why would that cause it to shut down at 50 mph.....
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 03:04:04 AM
Didn't relise you were running when it happened.your cdi and flywheel are your only timing there is a spot on the flywheel that triggers the fireing time and don't think you can change without some machine work or special cdi setup.Try your a50 cdi and look at the vacume lines,my guess is a line poped off or the cdi is crapping out(no longer fireing in time)Being dry is still on the start circuit,I would think
Title: Re: ..scoot shuts down..
Post by: sidthesloth on July 16, 2010, 12:50:43 PM
Sounds like you are suffering what brings a lot of people to this forum. With regards to what Art is saying about spark timing, there is a thread about that subject in the zx50 section, I think the author was asking about his engine running backwards. With my zx50 it would be a bitch to start when warm, but not shut down. My guess would be cdi, but you have spark. Since having mine set up with this cyl. kit it is now starting ok, so I put the previous hard starts down to worn rings in my old kit. Though it felt to be ok with compression something that Thebatman was told sounded strange to me at first, "good top compression poor bottom compression", to me that sounds like enough compression to run but not good enough vaccuum to pull the fuel through the carb. How was your scoot starting before this happened? Sorry if I am ranting a bit.
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 16, 2010, 02:48:58 PM
...it was starting great most of the time, but every once in a while, when it was cold, i wuld have to remover the filter and close off the carb's intake side with a piece of cardboard..take it off, fuel dripping out the carb, then it would fire right up...

..this all began when i snapped the firrst belt...lost some powerr then, and thought it was a split reed...


..this time, i was just running along when it shut down...thot it was another belt, just from the way it reacted...

..opened the cvt, and belt's fine...

..the dryness of the top of the piston and spark plug troubles me..like i'm not gtting fuel into the combustion chamber...
Title: Re: ..scoot shuts down..
Post by: sidthesloth on July 16, 2010, 02:56:16 PM
Maybe time to remove the head and have a look at the bore, the good part about two strokes. no cams, chains, push rods, rockers....
Title: Re: ..scoot shuts down..
Post by: Hoolander2 on July 16, 2010, 04:39:05 PM
Leak in the crankcase somewhere.  No vacuum on the upstroke means no sucking on the carb -- thus the dry spark plug.  Also would account for the hissing, loss of power, etc. You'd still feel compression when turning engine over but maybe not as much.  If it's that, your leak must've gone from small to bigger over time.  A compression check at the spark plug hole would not necessarily diagnose it.  Gotta do a leak down test.  Or it's possible you may find it by looking over the crank case from every possible angle. 

I diagnosed a crank case leak one time by observing tiny fuel/oil bubbles coming out the case gasket just after engine shut off.   

Don't know about yours but some 2 strokes have a check valve somewhere on the crankcase.  They can go bad or get dirty. 
Title: Re: ..scoot shuts down..
Post by: Hoolander2 on July 16, 2010, 04:53:46 PM
I'd look at the vacuum lines like Art suggests first though.  That would account for all of it. 
Title: Re: ..scoot shuts down..
Post by: art on July 16, 2010, 05:57:51 PM
I was going for the easy fixes,thinking you diagnosed the split reed allready,still look there first,cracked vac line and cdi if you can swap.The prior power loss and hissing though is a concern since we now know it's not a reed!The good news you wanted some 2t exp. they are easy to work on and relitivly cheap to repair.The bad news once your there you will want to upgear put in a racing crank and a bigger bore Ha! If you have all the parts it can be done in an afternoon.I,m leaning tward you lost a seal at this point,If lucky it's the base gasket if not got to split the cases.You can try to locate by eye,but leakdown test will give you results.I dont have alot of exp.here usually take to a shop for test,get diag then repair.If this is where you have to go I do have a stock piston and rings I can send your way with about 1000 kl on it,I also have a spare oversize piston  rings and race.took  about 3 months to get shipped,could also send,would need some reinberstment for that set.The only special tool you will need is a flywheel puller,you may have one that fits allready,if not get that and gasket set ordered now.Fingers crossed for an easy fix,Good luck!
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 19, 2010, 12:13:49 AM
..i'm listening guys...

..just ain't got into the ppl yet.

..hadda focus on my a50 for a ride to work...

..i be right back!!


peace
Title: Re: ..scoot shuts down..
Post by: sidthesloth on July 19, 2010, 01:01:21 AM
A50 going well? With your customised exhaust. :)
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 19, 2010, 01:08:07 AM
...lmao...yes it is...even better than before my troubles with it began.....


..reckon i shoulda bought me a comp. tester earlier on...

..but i got me a 2-stroker outta th' whole situation...

..so, i'm not too distraut...lol...

 ;D
Title: Re: ..scoot shuts down..
Post by: sidthesloth on July 19, 2010, 01:13:19 AM
Doh, after my last post I saw your post about the A50 going well. I slow sometimes. :)
Title: Re: ..scoot shuts down..
Post by: wordslinger on July 19, 2010, 01:14:57 AM
I slow sometimes

...lol...most sloths are...lmao....
Title: Re: ..scoot shuts down..
Post by: sidthesloth on July 19, 2010, 01:17:18 AM
Pay that! :D
Title: Re: ..scoot shuts down..
Post by: wordslinger on December 06, 2012, 01:35:45 AM
.....where the hell is sid??...


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