T-maxx high reving after some time running!

[WazabiQc]

Hey guys! It's me again hehe, as i am a complete beginner in rc, this forum is really useful to get my truck running fine thanks to all of you for helping me out ! However, i was just running the truck outside, and after almost emptying a tank, the truck began to high rev and jerk forward when idling, even if i was holding the brake! I thought it would be the lsn but i wanted some advices about this before messing something ! Thank you.

 

[Alexander_0_1]

That's normal, that's the sign to come back refuel, or come back refuel and let your rig cool down for a few mins.

 

[Nitrotrout]

Jerking is normal if your truck has the black 2.5 tranny with reverse.
This can be remedied with a Forward Only Conversion kit.
Keep in mind you'll sacrifice your reverse mode with this kit.

Sounds like you're experiencing the notorious "half tank lean" issue
common with the stock T Maxx fuel tank.
Try tuning your engine with half a tank of fuel or less.

 

[Childresshunt]

or you could do the ofna violator fuel tank mod. Eliminates half tank lean and lets you hold more fuel for longer run times. But as nitrotrout said the forward only conversion is the best mod possible for your transmission. Makes for a much smoother operating tranny

 

[WazabiQc]

i knew about the jerking caused by the reverse ! i was talking about idle jerking this time, not giving it gas ! but thank you all i'll look for the ofna tank.

 

[Nitrotrout]

i knew about the jerking caused by the reverse ! i was talking about idle jerking this time, not giving it gas ! but thank you all i'll look for the ofna tank.

That's most likely your clutch engaging and disengaging from high rpm idle.
Probably wouldn't hurt to inspect your fuel tank and what not, for air leaks.

Definitely tune with less than half a tank. Make some speed runs and adjust your HSN, then adjust your LSN using the pinch test.
Should stall out in 3 seconds give or take, and set your idle gap no wider than the thickness of a paper clip. .

Look into the Ofna Violator tank mod as the guys suggested. Great mod, pretty cheap and simple.

 

[WazabiQc]

well i just retuned everything.. i went to the hobby shop thursday, and there was a guy who set trucks up when you buy them from this shop, and found out it wasn't well tuned ! the idle gap was set too open, the LSN wasn't properly set.. it would always randomly jerk at idle ,the reverse didn't work properly because of the high rev and when i pinched it it was reving so high that the truck would move forward ! now it doesn't jerk anymore and it dies in about 3 second with a little rev up but not enough to jerk it . gotta set my shift point and HSN now .