2-stroke rookie --idles ONLY!

So, I got this super clean X1 last night for my wife. Oh yeah, I also picked up a super clean DM Brutale(?) for myself. The X1 had a loose carb. I tightened it and I can get it to idle fine. One problem, as soon as I touch the throttle, it dies. Any ideas. I'm no tuning guru. I have enough problems trying to wire my 2005 5.3L compterized V8 from scratch. My brain cells are dieing from all the new input!

Sounds like the carb maybe out of adjustment or even a dirty carb. The mixture screw is the brass colored straight headed screw on the side of the carb try resetting it to 2 1/2 turns out. Softly screw it to the right just until it stops but don't tighten it than turn it to the left 2 1/2 turns.

I'll give it a try. Thanks!

Okay, carb appears clean. Fuel supply is good. Gaskets appear intact. Everything is tight. Mixture screw worked best at 1.5 turns.

It fires and idles as long as the choke is on. If you open the choke (warm) the the rpm goes up and then within about thirty seconds less, depending on how much the choke is open, it will begin to slow and then die out.

Close the choke, it idles up and keeps idleing away. Open the choke or the throttle and out she goes. Pluuuugh.

Maybes?
Bad Plug
Bad Fuel
Leaking gaskets
Bad planetary alignment with the sun
Gypsy curse

Anybody got any ideas?

Ok sounds like a air leak. Get it started and spray some carb cleaner around the intake area. But not in to the air filter. If the rev's change when spraying you have a air leak.

Richen up the lowspeed jet...its the brass slotted screw on top of the carb that rotates.The factory setting for the low speed needle is 1-1/8 turns out.After you get it to run w/o the choke set the small silver philips idle screw..If the low speed needle becomes too loose and wanders when the engines running use either a drop or two of superglue or tire slime to hold it in place......Peace

Thanks CAM2. I'll try that in the morning when I get back from work and check for air leaks.

That's a 2004 X1 with CVT. Basiclly it's a X2 before they changed the name to X2.

Well, I sprayed the sides of the carb with carb cleaner while it ws running. The engine slowed and stalled if I sprayed more. I adjusted the slow speed jet and the mixture control as well as the idle. I adjusted the throttle cable. It will accellerate now and idle but if I keep it around mid throttle or crack it all open it will stumble and die.

Sure would be nice to have computer controlled fuel injection! Although, I think that would end up on my DM and I'd still have the problem on my X1!!

Thats an indication of an air leak and running way lean because of it..Change both of your intake gaskets and readjust the needles if needed afterwards.You can make new ones with gasket material from the autoparts store and an exacto knife or get direct replacements from the local mower repair shop..After you change out the gaskets you should be ok,,,On most of the 2 stroke piston ported engine bikes I get the plastic air filter boxes kind of shrink up or flatten out a lil leaving the carb mount screws too long to properly tighten the carb...Try adding a washer or two to each carb mount screw to ensure they dont bottom out in the intake so they properly seal the carb.Inside the fueltank on the end of the black fuelline youll see a filter stone that will probably need to be changed too.......Peace

Well, I went out and got a new carb since the old one wouldn't release to idel when the throttle was released. I used the old gas to start my leaf pile going.

I put in fresh fuel mix, installed the new carb with a new gasket between the carb and the intake manifold. Throttle returns fine now. I cleaned off the spark plug but I think I'll install a new one later. The engine starts and runs and accelerates. Unfortunately I think I could go faster in a wheelchair.

I'm not looking to race this bike. It's for my wife to try running on the local track against another couple wives. But this thing is a pig. I'm gonna go pooter around with the slow speed jet and mixture screw again now that it's stopped raining.

This bike is so clean it's a bit depressing that my daughter could spank it on her Blata 2.5!

I got it to idle pretty good. I didn't mess with the sealed low speed jet yet. Now it's time to take it out front for a test drive......cross your fingers!

Test drive went well. It accellerates alright but it does flatten out if you give it full throttle. Keep it a little off full throttle and it goes okay but it doesn't seem all that fast. I'll play with it some more and see what I can squeeze out of it. ANYMORE TIPS AT THIS POINT WOULD BE VERY APPRECIATED.

Is the CVT transmission adjustable? I haven't opened it up? Is it belt or chain drive? Do I need to add oil??

The reason why youre not going anywhere is possibly because of the CVT transmission...It is adjustable but it also has alot of variables for proper operation...one is the forward pulley inner sheave...it must slide back and forth on the spindle to put pressure on the belt to get it to ride up to the outter parts of the pulley to make a ratio change that produces more top end speeds..The other variable is the belt..If its too stretched out it wont grab right and it will slip...If its slipping youll have a big rubber build up in the case bottom..below is a picture of my X-2 with a totally worn out belt from the inner sheave being sticky........


Theres upgrades you could do to the CVT by changing the roller weights behind the inner sheave plate that slides to add more pressure to the sheave to get the bike to get maximum mphs......If you add heavier weights you should also add the stiffest spring you can to the clutch...


The engine can be upgraded with hp airfilter,velocity stack with built-in choke,homemade boost bottles,rocket key,rev pipe exhaust, 14 tooth front sprocket and stock ported intake.....Thats what I had half the work done to my X-2 less the rev pipe, velocity stack and hp airfilter and I had my X-2 up to 41 mph on GPS...when it was stock it hit 32-33mph;- so you have some tuning to do..I have all the work done to one of my X-1's and it went 28 mph after break-in stock and went 37-38 after mods....The sparkplug gap could be the problem to your leanburn condition if you cannot get it to tune right with the needles....The plug gap is supposed to be between .023"-.027"sae.............Good luck getting it to be a beast

Thank you all for your input! I got it running smooth. The transmission works fine. It is slow but that's no big deal. It's for the wife anyway. I doubt she'll get competitive enough to switch to an Italian pocket bike. But, she is a tenacious thing. If she decides to go faster I'll put her on my C1.

Again, thanks everybody for your help!!