Tony Kart 401R 2019 with Rotax DD2 Brake problems


(krikor yalmanian) #1

Hi Guyz. Im new to the Forum and need some help from experienced drivers. I got myself a new 2019 401R Tony Kart Chassis driving rotax max DD2 engine, which is amazing but only one issue im struggling with is the braking. When i brake coming from high speed straight the whole front of the kart vibrates ,what the reason is i feel the brakes are very powerful especially the front ones. I drive more with front brakes so i should find a solution for this vibration. It will be great if anyone has a solution . Thanks


(James McMahon) #2

If you have too much front bias the front end will “grab”.

For a vibration I’d look at…

Steering components:
Kingpins and kingpin bearings.
Steering column bottom bearing and top bushing.
Tie rod ends/rose joints.

Also:
Brake caliper mounting and pad security
Integrity of the caliper bracket on the spindle.


(krikor yalmanian) #3

Everything is brand new. First time practicing on it out of the box and base setup all OTK parts.


(James McMahon) #4

Reading your post again, you did say it’s new.

I would still check all of those components and hardware. Just in case. Once that’s verified…

Do you know what your toe is set to?


(krikor yalmanian) #5

i will check the hardware tomorrow and for the toe i think 2mm out on each side. But not sure again i will double check that tomorrow too. Thanks


(Peter Zambos) #6

Are the wheels balanced?


(krikor yalmanian) #7

after checking all the hardware on the kart there was nothing wrong…Toe is 1mm out from each side. i transfered the brakes to work more to the rear, that was pretty good with the vibration.


(Marin Vujcich) #8

Their brakes are renowned for being really aggresive. I for one, hate them.
The shudder is actually front wheel locking, or close too. There is a rational explanation for the shudder.
You don’t actually need to brake that hard in a dd2. Dont smack the brake hard initially and release pressure if it starts to shudder is more effective. Detune the front brakes till you get used to it.
I had the same experience driving a front braked otk kart the first time.


(krikor yalmanian) #9

I tried to turn the screw all the way towards the rear brake. But i can still feel the fronts are strong. So we will work on the screw and try to make something that can turn the screw more towards rear brake.