TT250 Jumpy throttle

[2t2t250]

Hello All,

My TT250 has a jumpy throttle that makes it difficult to ride on trails. Do we know if something like a throttle tamer is available for these bikes or if a throttle tamer will work on it? Any other cheaper solution would also be welcomed.

Many Thanks!

[zero_dgz]

Before going down that rabbit hole I would recommend you have a look at your throttle cable and make sure it is not wound up tight like a guitar string. Typically you want to have a few mm of free play/slack in the throttle before it starts to pull the cable. If it's too tight it can even keep the throttle open slightly even when you've completely let go. That's bad, obviously.



Failing that there are oodles of cheap Chinese throttle assemblies that have adjustable end stop screws out there, typically designed for pitbikes. But anything that fits 7/8" bars should also fit your bike. You can use these to artificially limit your maximum throttle opening. They're meant for teaching kids how to ride without them whiskey throttling themselves into trees.


I definitely would not want to ride a 229cc CG bike on the *road* with the throttle neutered, though...

[J4Fun]

I’m thinking you may have a throttle return spring either missing, broke or unhooked?

[zero_dgz]

Unless there is something Extra going on with the TT250, the only spring in the arrangement should be the one inside the cab, which pushes the slide down. These bikes tend to have a single cable throttle that does not have the "push" cable for positive closing as found in higher end bikes, nor is there a spring in the throttle tube on the handlebar. The spring in the carb handles everything, and the throttle tube returns home via just having the cable pulled.

[TxTaoRider]

If the jetting is stock, it can feel jumpy. Slightly lean carbs can have a very "on/off" feeling at small to medium throttle transitions, and at large/fast transitions can hesitate a brief moment before quickly accelerating , making them hard to control smoothly.

[braindead0]

My 140 was terrible until I swapped out the nibi carb for a chikuni from amazon.

[Hunnicutt]

Order a jet kit. Swap the stock 102 main jet with the 112 jet that comes in the kit. I guarantee your TT will feel like a completely new motorcycle!!


https://cscmotorcycles.com/jet-kit-c...e-sg250-tt250/
$12.95


Tutorial:

https://cscmotorcycles.com/tt250-car...maintenance-1/

[flopsweat]

Originally Posted by TxTaoRider

If the jetting is stock, it can feel jumpy. Slightly lean carbs can have a very "on/off" feeling at small to medium throttle transitions, and at large/fast transitions can hesitate a brief moment before quickly accelerating , making them hard to control smoothly.

Very interesting! I did not know this, as I have also thought my TT250 throttle was a little jumpy. Having never owned a bike before, I didn't have much to compare to.

Jet kit will be ordered shortly for me!

[2t2t250]

Thanks for the suggestions. I'll look at the cable and check for adjustable cables somewhere. The carb has been jetted, although, I bought the bike used and don't know what size they actually are. The darn throttle tamer looks like $70, if it will even fit! That's a no joy!