rm250 carb with power jet??

[t_shee]

bought a 39 pwk from a buddy got to looking online and found it is the same one used on some rm250 dirtbikes. it has an electrical solenoid on the side of it and a tube running inside of carb from it. looks like it is opened up electronically and sprays more fuel. anyway i just got this project all put together and it wont start. it is getting good spark and tries to hit but just wont fire up and stay running. also it is kicking back like crazy and will punish your ankle or shin if your not careful. anyway my question is will this carb work and is there anything special i need to do? it has 2 extra vents on the front pointing straight up (airstriker?). i had no good idea on where to start jetting wise so i put a 55 and 168 with needle in middle. i figure that should be close enough to start but its not happening. i just rebuilt top and bottom end although i havent done a leak down test. is something else going on and that is why it is kicking back? any help would be appreciated thank you.

it is this exact carb RM250 SUZUKI 2000 ** RM 250 2000 CARBURETOR | eBay

[t_shee]

forgot to mention. the bike came in pieces and there were 2 cdi's a ricks and an oem. i tried both and no difference. i went ahead and ordered one since i see there are some problems with them

[bigred]

maybe timing is off

[t_shee]

Took flywheel back off last night and everything looks good. I did notice when I put oem cdi back on it doesn't kick back anymore but still won't run. I think u are right about timing but what do I check? Ignition is all stock and keyway looks good. I noticed 89s use a differerent stator, mine came from ebay how do I no its right for my 86?

[acecarlos]

48-52 Pilot/168 Main is a good starting point on the RICH side (main) for an OEM cylinder...you can use the carb, just bypass the solenoid. Timing is not variablle on stock OEM IGN TRX250R/ATC250R IGN systems...if keyway & flywheel are located properly, timing is pretty much set. A bad flywheel will sometimes allow kick backs. Also; Kick back can be related to a bad CDI, bad pick-up holder (cracked or broken), Bad flywheel, poor Ground, and bad fuel delivery (inproper jetting, loose needle, large Pilot jet) or broken, cracked or worn out reeds.

You can check timimg by bringing the piston to TDC, right before TDC the raised tigger on the Flywheel will pass by the coil pick-up and once at TDC the trailing edge of the raised trigger will leave the coil pick up button. Also look at the "F" and "0" marks on the OEM flywheel...a 2 stroke timing light will verify timing.

Carlos.

[t_shee]

Great info. Thanks carlos. My cdi came in mail today so I will play with it more tonight how do I bypass the solenoid?

[acecarlos]

Just don't connect the wires on the solenoid...

Understand that the solenoid on the Keihin 38MM PWK actuates the Power Jet from 1/4-3/4 throttle...it richens the mixture or jetting to provide more TrQ through that range, that is the intent of the solenoid. Once you disconnect the solenoid, you loose the Power jet's function.

Honestly; the PWK solenoid/electronic carbs are not an option I would consider when looking for a good TRX250R carburetor...the non-electronic carbs like the Kehin PWK 36MM-40.5MM are much easier to tune and more than sufficient for our application.

Carlos.

[t_shee]

ok thank you. i got it for 50 bucks so i will run it for now.

[t_shee]

Got it running last night. There was a mouse nest in the expansion chamber. It was well constructed considering It held up to us trying to pull start the bike lol