ty 250 1974

[cainsy]

hi, just wondering if any one can tell me what size pilot jet my bike should be running. I have just got it running[ new piston and rings ] but i can only keep it going with the choke on once the revs drop, so i checked the pilot and it is blocked. tried everything to clean it but no joy so i want to buy a new one for it. I am also looking for any parts to suit the bike so if anyone has some they are wiling to part with (for a price) i would be interested.Thankyou

[David Lahey]

If you have the TK carby that came standard on the A model, you can buy the pilot jet as a spare part from Yamaha. I think they use a different numbering system to Mikunis for pilot jets.
I think the standard pilot jet for the TY250 twinshock type OEM Mikuni is #35. I'll check to make sure later on tonight.
Haven't you got any fuse wire to poke the jet hole with? If you are still stuck, you can take it to an optometrist or a jeweller and get them to put it in their ultrasonic parts washer.
What parts are you looking for?

[cainsy]

thanks for the info on the jetting. i'm after front and rear mudguards mainly i know there are places to get new ones but i am just trying to keep costs low , other things are front brake cable , lever and perch and finally a muffler as the one i have is not the original.

thanks for your response.

[David Lahey]

OK the standard pilot jet for the TK carby is a #50 TK pilot jet and they list #48 as an alternative.
The original TY250 B,C,D carbies have a #35 Mikuni pilot jet as standard.
If you want a standard muffler, you should be able to pick one up relatively easily nowadays because the aftermarket one made by WES has become quite popular.

[cainsy]

hi, i have a tk carbie and i thought that it said 50 on the pilot but it looks as if it has had a hard life and the face of the jet is pretty damaged so i was unsure , thanks for clearing that i try cleaning it out again if not i'll get another one . CHEERS