Need Help Guys (1985 Tri-Z 250)

[The R]

Okay, here goes.

I have a 1985 Yamaha Tri Z 250 and I just put my piston, cylinder and head back into the beast (all cleaned up) and now it won't stay started I was told that the only reason it ran before was because of all the black stuff on top of the piston that kept the engine sparking (even when I tried to turn the damn thing off it would keep running). The following is the exact quote from Dennis Kirk website for the carb I bought from them.

" TMX 38 mm Flat Valve Carb
Part Number 1656
Manufacturer: Mikuni
Type: Carburetor

Faster and smoother air flow at the venturi results in better atomization and increased throttle response

Power-Jet kit may be used

All TM type carbs use most VM components

For use with a fuel pump order valve PART NO. 17-978, $13.99 (TM32, 34 only)

SPECIFICATIONS:
Spigot OD: 43mm
Main Jet: 340
Pilot Jet: 25
Inlet Valve: 1.5
Needle Jet: 389 Q-0
Jet Needle: 6FJ40
Throttle Slide: 4.0
Choke Type: Cable"

The only carb change I've made is to move the E-clip on the jet needle two notches up to lean it out more (I thoght maybe this carb was giving the beast to much gas.

I've eliminated the stock airbox configuration and put a K&N round airfilter directly onto the carb

I've put Boyseen Reeds in the beast, New NGK spark plug gapped to .030

I've got it to start a couple of times (playing with the throttle screw, and Air adjuster screw) but once it would start if I would touch the throttle it would bog down and cut off. I even got it started and let it run for 3 minutes and as soon as I touched the throttle it cut off. I'M DYING OVER HERE !!!

Any suggestions would be very helpful, I'm dying to get my trike running again, this is memorial weekend, and I wanted to take the beast up north for some riding, but I can't get it to start, or stay started.

I need some help ASAP guys!!!

Thanks

[mudduck14843]

try unplugging the kill switch there might be a short

[The R]

It's a brand new switch I installed, and it works good. I think my problem is the carb setup.

Thanks for your input!!

[J.D.]

Ok you say you can get it to run until you give it gas....have you checked the plug, what color is it?(check after run)

[The R]

The strange thing is, there is no color :?: I mean I've pulled the plug after it ran and it looked just like it did when I put it in (it's brand new, I just put it in today) I've tried starting the beast in the last four hours and it won't start at all now.

Thanks

[The R]

Anyone else has any ideas

[Instinctz]

Put your stock air filter/box on it..

Also reset your idle/mix screws... if you dont know how..
Basicly: Idle Jet needs to be 3 + 1/4th turns out. The othern Im not sure right now, cant remember.. somehwere near that though.

[The R]

Put your stock air filter/box on it..

Also reset your idle/mix screws... if you dont know how..
Basicly: Idle Jet needs to be 3 + 1/4th turns out. The othern Im not sure right now, cant remember.. somehwere near that though.

I don't have the (joint) part of the stock airbox system

[mudduck14843]

i think i have one

[The R]

anyone else have any ideas??

[The R]

New information, I've pulled the carb and it doesn't seem to have any gas in it, but the fuel pump is working because when I pull the hose off the petcock and turn on the fuel it starts to leak all over, so now I don't know what to do next. how do I know if I ran the hose from the petcock to the carb wrong? Is there a certain way I have to run the hose? Since I can't get the trike running, how can I test the fuel system? Help me guys, I'm trying to fix this myself, because taking it to a shop isn't any fun:(

Thanks

[J.D.]

Take the hose after the petcock, the one that goes to the carb, take it off turn the petcock on, turn the carb line petcock on(turn BOTH petcocks on) and see if you have gas. If no gas, kick it over(this will create vacuum on the lines, and make fuel come through the line). Make sure gas is coming through that line. Something else you may want to give a try just to get the whole deal started, fill the bowl up with gas, put the carb back together carefully to keep the gas in, and try to get it run like that, it may start sucking the fuel then like it should. Best of luck to ya bud

[The R]

Take the hose after the petcock, the one that goes to the carb, take it off turn the petcock on, turn the carb line petcock on(turn BOTH petcocks on) and see if you have gas. If no gas, kick it over(this will create vacuum on the lines, and make fuel come through the line). Make sure gas is coming through that line. Something else you may want to give a try just to get the whole deal started, fill the bowl up with gas, put the carb back together carefully to keep the gas in, and try to get it run like that, it may start sucking the fuel then like it should. Best of luck to ya bud

Thanks for the input, I'll try that now!!

[J.D.]

Lemme know how it works for you...if it doesn't work after that, your fuel pump is shot. I might be able to hook you up with one.

[The R]

Okay, I unplugged the hose from the petcock and turned it over and the fuel ran through the hose a little every kick(i don't know how much is suppose to run through it). And it still didn't start. So I decided to give it some throttle when I kick it over a BAM it started, BUT it cut off as soon as I let off the throttle (2 minutes later). This trike hasn't ran right since I purchased it, So I'm thinking maybe there is something wrong that I can't fix (I'M NEW TO THIS ENGINE STUFF). If anyone has any more ideas please share, but If I can't get it running by tuesday I'm going to take it to a shop and have them fix it.

Thanks

[J.D.]

Ok tell me something...if you keep the throttle open, will it stay running? If that's the case, I'll tell ya what to do to make it idle.

[The R]

Ok tell me something...if you keep the throttle open, will it stay running? If that's the case, I'll tell ya what to do to make it idle.

YES, Once I get it started (takes forever) as long as I keep the throttle open almost half way then it won't cut off.

Thanks.

You can e-mail me @

ther@pc-tecks.com