Hard to start TTR125- Help!

Here's the deal- I bought an 01 TTR125 that had been wrecked & sitting for 4 yrs.(for $200, by the way) Brought it home cleaned the carb(disassembled & dipped) , changed the pilot jet to a 17.5, turned the fuel screw out 1 1/2 times, replaced the choke cable, removed the snorkle and changed the spark plug. It runs like a champ when warm, idles fine & is crisp, but is a bear to start when cold. Using the choke doesn't seem to do anything. It takes lots of kicking, then begins to hit, then hits a little more and finally sputters to life. As I kick it, fuel leaks out the overflow hose. When its warm it starts 1st kick. The Main jet is stock. Any ideas what to try now? Thanks for any suggestions in advance.

I have the same proublem but i have a 110 main jet in there.

I just dynoed my 125 in Denver, where the air/fuel mixture should be richer, and the 17.5 pilot still gave me a very lean starting mixture. I put a 20 in it, and it starts right up.

I just dynoed my 125 in Denver, where the air/fuel mixture should be richer, and the 17.5 pilot still gave me a very lean starting mixture. I put a 20 in it, and it starts right up.

it should start with a 117......your choke prob isnt working right,,,,,choke on this carb is always a problem......also 1,5 turns doesnt seem like enough for a 117.

if your fuel screw is in too tight it would act like a smaller pilot jet. and be hard to start regardless of the jet.......stock carb stock bike 117.5 and 108-110 @ sea level about 2.5 turns out.......make sure the choke is actually working.....that what i ran when i used the stock carb.

Not exactly sure how to tell if the choke is working? Other than to pull the handle & make sure plunger is moving? I'll try another turn on the fuel screw too.

One way to tell if the fuel enrichment circuit is working, once you get the bike started and warmed up, it to pull it up and see how the bike responds. It should idle higher when the bike is warming up, and sputter a little when the engine is warm.

Later tonight I'll go play with the fuel screw and see how it goes.

Went another turn (2 1/2 turns out) on the pilot jet w/ the same result. What should I try next?

Focus on the choke. The plunger is a an aluminum POS and deforms with normal use. See my post on changing to the DRZ brass unit if you're mechanically inclined. Otherwise, replace everything below the threaded plug w/ OEM and I bet you are all go.

about the problem with the fuel leaking out the over flow tube its either from u kicking it to much or when u took the carb apart you might have put the floats in wrong i have done it before idk if its ur case i would just check

Sometimes the choke doesn't stay up. Try holding it up as you kick. If it starts when you are holding it up the mechinism that mounts to the triples is busted. The detent ball and spring is junk or the plastic is broke.

make sure the valves are properly adjusted. it's very easy to do. it will take you 30-60 min and can make the world of difference when starting

Focus on the choke. The plunger is a an aluminum POS and deforms with normal use. See my post on changing to the DRZ brass unit if you're mechanically inclined. Otherwise, replace everything below the threaded plug w/ OEM and I bet you are all go.

The wifes bike is the same way (05 125LE). How can I find this post? :thumbsup:

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