Do I need to rejet my 2007 TTR50?

[smellmyexhaust]

The bike starts up ok with choke on. Runs alittle too fast on choke.Is there a slight adjustment I can make to bring the choke speed down just a tad ? After starting the bike, it needs maybe 12-15 minutes of warm up time before I can take off the choke or it will not idle. When the bike is running it will only idle at a SLOW setting when I adjust the idle speed a little bit on the high side. If I bring down the idle speed to a slow rpm the bike will keep running but the rpm will continually fluctuate and the bike will die when putting it in gear. I've been told that this bike runs very lean from the factory. Is that true? I live in the desert of California and @ 3900 ft. above sea level.
Do I need to rejet? What sizes do I need in a main jet and a pilot jet? Anyone out there experienced with the ttr50 Mikuni VM :bang: :bang: 13mm carbs?

 

[Ol'89r]

If the bike has not been started in a while, your pilot jet could be clogged. I would start with cleaning out the carb and making sure every jet is clean and you can see daylight through the jets. Also, when the jets are removed, blow air through the orifices that the jets came out of to insure the orifices are clear. The gasoline blend sold here in Communist Kalifornia is only good for about 6-8 months of sitting before it goes bad. You can thank the EPA for that. :fft:

It's true that these bikes come very lean from the factory, especially the ones that are sold in Kalifornia. (You can thank the EPA for that too.) If the carb is clean and the problem still exists, try going up a couple of sizes on the pilot jet. If you are not sure which jet is the pilot jet, refer to your service manual or go online for an exploded view of your carb.

 

[dirt bike dave]

It's true that these bikes come very lean from the factory, especially the ones that are sold in Kalifornia. (You can thank the EPA for that too.)

Good thing we got the EPA and CARB to protect us from all the pollution that would result if Yamaha put the correct jets in the TTR50, lol.

 

[Dirtjunkie85]

I would definitely try cleaning your carb and checking your jets. If that doesn't help your going to have to play around with the jets. Good Luck!

 

[smellmyexhaust]

Ill start with a cleaning.

Thanks to all of you for jumping in and offering to help. Ill start with a good cleaning. I just had an mx racer (locally) tell me that I should check out my air/fuel mixture screw for a broken tip. he said they do break off occasionaly
and as a result they will not tweek out the air/fuel mixture at all. Well guess what? LOL I checked out that screw and sure enough the tiny needle like tip broke off. So Ive ordered another. Im going to do a good cleaning of the carb first and replace/adjust the idle. Thanks again!! :nod: :ride: