50cc 2stroke Lifespan

[Peters]

The larger of the two would be the idle speed. The smaller would be the idle mix.

Try installing the pipe and new jet and just see how it runs. You may have to turn the mix screw out a little. The idle speed screw is exactly what it says. Won't hurt to play with it until you get the idle speed where you want it. Always remember where you started so you can always go back.
Good luck

Idle mix instuctions for reference
They say the mix screw should be 1 and 1/2 to 2 turns out. So you turn it clockwise and count the turns until it seats. Remember the number of turns so you can always return to that position. Then turn counterclockwise 1 and 1/2 to 2 turns and do a idle plug chop.

[macocoy]

So pretty much the two screws on the side of the carb are for idle,nothing to do with high/medium speed?
On my carb the 2 screws sit almost next to each other(one faces horizontal and the other in incline position)Is yours the same as mine?
So Peters when you upjet ,that's the time to turn the mix screw?What about the Pilot slow jet do I have to mess with that too,?
I'm starting to hate watching that brand new tecnigas in the living room
And not on my scoot,I'll be doing it soon.

[Peters]

So pretty much the two screws on the side of the carb are for idle,nothing to do with high/medium speed?

Exactly Right

You should not have to change the pilot jet. The air/mix screw is just for fine tuning but you should get the right mix just by adjusting that a little to compensate for less restrictive exhaust.

From what I remember the pilot jet is used from idle to 1/4 throttle. The slide needle controls 1/4 to 3/4 throttle. And last the main jet kicks in at 3/4 to full wide open throttle.

Slide needle is not adjustable but I have read on here about people using a beer can to make a shim. To shim the needle up slightly. I couldn't ever figure out how to remove the needle from the retainer. I was afraid of breaking it. I tend to do that . Anyway, you shouldn't need to do that. Is required with more modifications or aftermarket parts.

Let me search for an old post on here explaining it. It can get very complicated when adding lots of aftemarket parts. I only had to change the main jet though. Ohh, let me see if I can find a pic of my carb too.

[Peters]

http://www.kymcoforum.com/index.php?topic=2150.0
This was about a year ago when I started work on mine. Read the whole thing I got a lot of good advice. I was pretty apprehensive about messing with the carb then too. A couple of things I did wrong: I striped one of the stud bolts that holds my carb to the intake manifold because the carb has nuts in a little pocket on the side that I guess were slightly cockeyed when I put it back together. Also watch that you dont pinch any wires or hoses when you put it back on too.

Sooooo I remember now I tried to take a pic of my carb to show them but couldn't get a good one.
Let me search some more.

[Peters]

http://www.kymcoforum.com/index.php?topic=1165.0
Look at wordslinger's link and read the threads. I learned a a few things myself.

Also do some searching and reading on here. You'll have to dig through a lot of BS but you will learn a lot.

As far as which screw is which. Hard to say without a pic or being there to look....
I just looked at mine and my mix screw is slightly inclined too. The speed screw is completely horizontal.

[macocoy]

Peter lots of good info again,you're life saver.if you didn't advise me I would have put on my exhaust without upsetting as some folks here told me no need to upjet as long as I keep my stock air box.I would have been running lean (broken engine).
We both have the 2009 2stroke model so I'll follow whatever u did,I'm not thinking of buying open air filter,I'll stick with stock air box and maybe drill holes later on.It rains here in Hawaii(my part)about 30% of time.Don't like the idea of water getting in carb.

[Peters]

I'm not thinking of buying open air filter,I'll stick with stock air box and maybe drill holes later on.It rains here in Hawaii(my part)about 30% of time.Don't like the idea of water getting in carb.

Good idea. I have trouble in the rain sometimes with the holes in my box

Well I thought mine was a 2009 but when I finally got my title from the dealer a few weeks ago(almost a year after I bought it RIDICULOUS ) I found out it's a 2010. I'm pretty sure they are the same engine though.

Good luck and let us know what happens. Feedback is great for the next guy/girl that comes along.

[macocoy]

Sure thing Peters.By the way what is the size of your main jet right now?And when you drilled hole on the air box,did you drill on the cover (outer part) or behind (tire side)?
I just came back from the dealer looking for main jets but they couldn't find any(out stock).So I'm kinda thinking of drilling,hopefully it works..
Will be installing new pipe my next dayoff.I let you know the progress...

[Peters]

Sure thing Peters.By the way what is the size of your main jet right now?And when you drilled hole on the air box,did you drill on the cover (outer part) or behind (tire side)?
I just came back from the dealer looking for main jets but they couldn't find any(out stock).So I'm kinda thinking of drilling,hopefully it works..
Will be installing new pipe my next dayoff.I let you know the progress...

My jet size? uhhh..... I am at like a #95 or .95mm. I am not positive on the exact size because the bits I bought went from .90mm to 1.00mm. I had to take a 1.00mm and very slightly grind it on a taper. Then I compared how far the bit went in on the #95 jet I bought(wrong threads). After I measured the depth it went in I drilled my stock jet to the same depth. So the wrong jet did actually come in handy to compare to the jet I was drilling.

I think I have it a little rich with the .95. Better a little rich than lean.

Important! Only drill holes in the air box cover. If you have holes in the box itself(beside the tire) you would be pulling in unfiltered air(bad).
You have to drill the holes on the dirty side of the filter(the cover) so the incoming air can be filtered.

[macocoy]

Okay thanks,I guess my target will be #95,seems large compare to my stock #75.How many holes 1/2 inch should I drill on the cover?
I ordered the torch welding tip cleaner,hopefully it will tell me size in (mm) so I can just copy what you did.I wonder how heavy the roller weights that came with the tecnigas next r?r u using it?Oh when u put the solder in the jet did u put it on the head or tip?thanks

[Peters]

Start with like .90. The best thing to have is some welding tip cleaners and work your way up one at a time. When you get to like a .90 try it out and see what happens. Climate and elevation have a lot to do with it so you may not run the same jet as me.

Do a WOT plug chop. Warm the engine up on the plug you have now. Pull the old one out and install a fresh plug. Take off at Wide Open Throttle. I like to do a few miles to get a good sure color on the plug and kill the engine while still holding the thottle open. Pull the plug out and look at the white insulator. You want like a dark tan coffee color. The reason it's called a plug chop is some people cut the thread base off on the plug exposing the white insulator for a better veiw. You dont have to do that though.

Start with like 1 or 2 holes in the air box cover. Not sure on the weights that came with the pipe. I run 6.5g or 7g rollers now. Can't remember now . You should heat the the head where the hole is(thats what she said Sorry. I like to take the tip out of a soldering iron, put the iron in a vise, and fill just a little solder in the hole. Not to much. Make sure when you drill the hole you drill it straight not on an angle. Again a vice is helpful.

[macocoy]

Change the exhaust to the tecnigas,took a test run for 3 minutes ,then decided to drill main jet to #90,put everything back together.and Now my scoot woudnt start......Help........

[Peters]

Allow a minute or two after the first few turns of the engine for the fuel to fill the carb. I think I had to turn my idle speed up a little. You may need to twist the throttle a little as you try to start it if you havent already. Try taking the air box cover off leaving the filter in. Try starting it that way. I find the best way to start mine when it's being difficult is to use the kick start. Trying too long(20-30mins) can flood the engine. Helps to let it sit an hour or two if you think you flooded it.

[macocoy]

Yehey,I did exactly what u said and after about 15 kicks,it finally started.I was about to bring it to the dealer(who knows how much they'll charge).you just save me big bucks.
I was already starting to panic.
Past days was depressing thinking I just broke my bike...Until I read your reply.
Maybe I should post something about that experience,I bet someone is going through all that.Thanks Bro.

[Peters]

Great. Glad you are relieved  .
So you got it running the way you want again?
Hows that 90 jet?
Have you done a WOT plug chop?