Jump to content
Sign in to follow this  

TTR 125 tuning help/question

Recommended Posts

I've been a dirt bike rider all my life. Many years ago even a racer. Well my sons are growing up and I recently bough a TTR 125L for the oldest. It's a 05 very clean all stock.  I was lurking here and read pages and pages of info on the carb. I ordered the 17.5 pilot and 110 main. Started first kick after the jet install. I have the pilot/fuel screw at about 1 3/4 turns out. My question is about getting a steady idle.

 

Problem: Warm it up and come to a stop on level ground, sometimes the idle will slowly speed up. Or if you lean it to the left the idle speeds up. Lean it to the right no change at all stays runnig normal. You can blip the throttle sometimes and it does not come back to a slow idle, it slows but not back to a putaput putt. You can tap the kill switch a few times an it comes down to a nice idle. ??? Do i not have the pilot/fuel screw right? Float?

 

Now the weird thing is my other son's xr70 does exactly the same thing. What ever I do they both do exactly the same thing. Both carbs were dissasembled and ultrasonic cleaned.

 

Before I put in the new jets, the ttr was hard to start cold and to keep it running I had the pilot/fuel screw about 3 truns out and the idle almost all the way in.

 

 

Thanks

 

 

Share this post


Link to post
Share on other sites

What you are describing is a hanging idle, caused by a lean idle/pilot circuit. You could try turning out the fuel screw another 1/2 turn.

It will get better as the temps get hotter, since the bike requires less fuel when it is hot.

The 17.5 pilot works great compared to the 15, but on the dyno, a 20 pilot worked even better, and gave 13-1 air/fuel ratios.

Share this post


Link to post
Share on other sites

What you are describing is a hanging idle, caused by a lean idle/pilot circuit. You could try turning out the fuel screw another 1/2 turn.

It will get better as the temps get hotter, since the bike requires less fuel when it is hot.

The 17.5 pilot works great compared to the 15, but on the dyno, a 20 pilot worked even better, and gave 13-1 air/fuel ratios.

Thanks I'll give it a shot. It's about to rain here for the next couple of days unfortunatley. I was just amazed that I tuned both of them to have the same problem. I guess my ear/seat of the pants is a little lean.

Share this post


Link to post
Share on other sites

Yep, thanks just turned it out a touch more and it's perfect.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×