Sticky/Jerky Throttle On TTR 125??

Just bought a used 06 ttr125, I got it cheap bc the guy said it was running bad. First test ride the throttle was VERY sticky, had to open and close it by hand, it was jerky and hard to control. Took the throttle tube off the bar and there was sticky residue everywhere, clean it up and put some gun oil on it. For good measure I changed the oil, cleaned the air filter, and cleaned the carb and jets. Rode it again and it was MUCH better, the throttle feels nice and snappy in my hand. but while actually riding it's still just a little sticky and sort of tricky to control. What else should I try? The cable looks ok as far as I can tell.
 
Take the thottle tube off, and pull the cable by hand. See if that is any better. If its better, than its still your trottle tube. If its not any better inspect and try to lube the cable.....

If the throttle has been stuck fully open for awhile... Your spring might be weak now.
 
Pulling the cable by hand it seems decently smooth and has good resistance and snaps back when i let go. I did go ahead and take the tube back off and wire brush and file the handlebar to where its perfectly shiny and clean then lubed it again and put it back on, it feels better in my hand just sitting here but I'll see if it feels better when I ride tomorrow.
 
If you posh the throttle tube too far in it will bind. The only true cure is an aluminum throttle tube with a ball bearing end cap. That what I run on my TTR.
 
Check the carb slide for burs.
Not sure it is burs on the slide if it works perfect with just pulling on the cable and "snapping back", but I could be wrong. It seems to all lie in the throttle tube. If you don't get the results after doing a complete cleaning of the throttle tube and bar area, then it is time to purchase a new tube.
 
Not sure it is burs on the slide if it works perfect with just pulling on the cable and "snapping back", but I could be wrong. It seems to all lie in the throttle tube. If you don't get the results after doing a complete cleaning of the throttle tube and bar area, then it is time to purchase a new tube.

Yeah I think you're right, the kid must have put glue on the grips or something bc they whole bar was sticky as hell. The carb slide is fine, it moves freely in the tube. I think I may just bite the bullet and get a Moose billet throttle tube and be done.

The good news is it runs great except for that so I saved 500 bucks over an easy fix :)
 
Yeah I think you're right, the kid must have put glue on the grips or something bc they whole bar was sticky as hell. The carb slide is fine, it moves freely in the tube. I think I may just bite the bullet and get a Moose billet throttle tube and be done.

The good news is it runs great except for that so I saved 500 bucks over an easy fix :)
:thumb:
 
Well I took it on another test ride today, and the throttle tube feels great. But it still feels a bit jerky, the best way I can describe it is when I let off the throttle, it actually feels like im engine braking a tiny bit. Instead of just coasting at the same speed when i let off, it slows down a little. Any Ideas?
 
From what you say it sounds normal. Four strokes can give a surprising to some amount if engine braking. Particularly if you are running in the lower gears. I might have missed it, but did you clean out the housing that clamps to the bar?
 
But should it engine brake just from letting off the gas? Not downshifting or anything...? Its really hard to keep the throttle smooth at low speeds.
 
You will notice it more when you are in a gear that may be lower already than necessary. On bikes with drum brakes it can come in handy. Practice is necessary to make it all go smooth.
 
This is normal. 4 strokes engine brake as soon as you let off the gas. Riding a 4 stroke you learn to shut off the gas much later before getting to a turn where a 2 stroke you will let off sooner as they coast more.
 
Top