A forum for owners of Yamaha TTR250 trail and enduro bikes!

dannydandan · Member

ttr 250 project bike not getting fuel

TTRfan · Super Guru

With the top off the carb, can you check that the throttle is depressing the diaphragm when opened and that the diaphragm rod is moving up and down freely with the throttle movement?

Also, have you fitted the spring under the diaphragm rubber? If not it won't be drawing up fuel.

Brian

dannydandan · Member

hi brian yes had carb top off also and seen everything seems to working find and yes i have a spring under the diaphram rubber i have seen fuel coming from the nozzle when looking into carb with airbox removed but not really i good squirting stream of fuel more a small spert ( i have had carb cleaner sprayed through this which came thru very well but i have not had a small wire down to clean as i dont have one to hand but it didnt seem blocked. could i need a new diaphram seal ?

thanks again for help

TTRfan · Super Guru

If the diaphragm rubber isn't too "tired" such that it is ballooning and it isn't holed then I think you need to be looking elsewhere. Is the non-return check valve doing its job? A quick "suck and blow" on it should tell you if its working OK.

Carb strip 008.jpg

dannydandan · Member

i have had this valve out and given it a good clean and it seems to move easy when sprayed with carb cleaner. now i have been reading some thread on here and i think i have sussed how to remove slide so i can raise needle would rasing needle affect the fuel going in to carb? but first need to (doctor) a rounded screw with my dremmel so i can remove it.

i had the bike running today the best i have seen it still back firing but running and seemingly smooth ish just seemed to not want to be revved hard so had to tickle revs to keep it running maby a min or so. removed plug after i had running and was slightly black nothing major bike seemed too heat up fast but no where near as bad.

i must be getting close now to getting bike running now and i wont stop until i do thanks to this site.

tommoro i will remove carb again and bring indoors give another good clean check all jets raise needle a notch or maby two try to find some good enuff wire to help clean the nozzle which the fuel should be squirting through i will try to make up a better photo and description of things i am doing thankyou for reply :) cant wait untill all the hard bits done and then can get it looking nicer ! hopefully