tt 01 trouble

[bishy]

iv just bought a fusion 10 turn motor and for some reason when taking off from stand still the car drifts off to the left any one know the problem please let me know

[terry.sc]

Firstly, please don't post the same question in multiple threads, most

people check all the posts and are less inclined to answer the

question after reading it several times.

You have a 10 turn motor in a TT-01 shaft drive car. Due to the

transmission design with a powerful motor it will always pull to the

left under acceleration and right under braking. It is caused by the

motor trying to twist the car under hard acceleration. This happens in

all cars with a central driveshaft and longitudinal mounted motor, the

more expensive cars have had a lot of development work to reduce it to

a minimum but it is still there.

If you still want to use a 10 turn motor the only answer is get a belt drive car.

[MikeT]

True Terry, a belt driven car will cope alot better, atleast the handling side of things!

 

Now, if the driveshaft were weighted to the EXACT weight of the armature, and rotating the other way, wouldn't this cancel it out?

[MAD ANDY]

i hjad the same problem on my hopped up tt01....it was running a reedy 7 x 2 motor

i managed to control the problem by fitting a ball dif a one dif in the front, tamiya universal shafts, alloy arms hub etc.....ok the problem was still there, but no where near the same amount, i never experienced the real drift again, as all the drive train was stiffer, also i ran the tb01 evo prop and evo alloy prop cups, carbon top chassis etc .....lot of money to spend, and to be fair, for the money i spent, i could of brought 2 trf 415 msx's lol

if u want real competive car, sell ya tt01 dont spend any more money on it, and save the parts money u would of spent on  it.

 

andy

[DJTheo]

True Terry, a belt driven car will cope alot better, atleast the handling side of things!

 

Now, if the driveshaft were weighted to the EXACT weight of the armature, and rotating the other way, wouldn't this cancel it out?

Only if the motor is also parallel to the driveshaft and the moment of

intertia (not mass) of motor armature and pinion has the opposite ratio

as the pinion/spur gear ratio to the sum of inertia of the driveshaft

and the gears driven by it in longitudinal direction (bevel gears and

spur). For example if pinion/spur gear ratio is 1:3, the moment of

intertia of the driveshaft subsystem should be even 3 times higher then

the one of the motor subsystem. Rotating direction is fine as motor and

driveshaft always rotate in opposite directions but problem is that the

armature has already a very high moment of inertial (big mass

concentrated on a big outer radius) so by making the drifeshaft and

gears having sutiable intertia for it would make the transmission very

massive and "dull" in acceleration.

Cheers

[terry.sc]

True Terry, a belt driven car will cope alot better, atleast the handling side of things!

 

Now, if the driveshaft were weighted to the EXACT weight of the

armature, and rotating the other way, wouldn't this cancel it out?

A couple of points. The axle doesn't rotate at the same speed as the

armature. Also one rotating mass is on the centreline of the chassis, the other one around 20mm off centre.

The problem isn't in the rotating mass ( although it

does have an effect) the bigger problem is depending on which way the

driveshaft rotates under acceleration the motor is trying to either

climb over the driveshaft or go under the driveshaft, dragging the

chassis with it.

Even if the rotational mass are identical (which it cannot be as

rotational speed is included in the equation) the only thing stopping

the car turning over is the suspension pushing back. When the car

accelerates the suspension on one side is loaded up more than the

other, which is why they head off in one direction and the other

direction when braking.

[DJTheo]

Terry, as I wrote in my above post the problem is actually them moment (torque) of inertia and it could be balanced if the moment of inertia of the driveshaft system would have an inertial moment of the opposite ratio, but that would make the transmission much too "heavy" and "lazy". Also a transmission with big moment of inertia makes the car unwilling to steer and handling weirdly, due to gyroscopic torques.

Cheers

[MAD ANDY]

yep, u can get all technical etc, or maybe just some good quality take off cs 22 tyres and inserts will stop the drift????  just a thought

 

andy

[terry.sc]

Terry, as I wrote in my above post the problem is

actually them moment (torque) of inertia and it could be balanced if

the moment of inertia of the driveshaft system would have an inertial

moment of the opposite ratio, but that would make the transmission much

too "heavy" and "lazy". Also a transmission with big moment of inertia

makes the car unwilling to steer and handling weirdly, due to

gyroscopic torques.

Cheers

The problem with balancing the moment of inertia is that although the

moment of inertia is fixed for any speed the torque to accelerate it is

relative to the angular velocity. yes, you could also add to the

transmission to balance it out but surely it would need to alter to

cope with the different loads at different speeds.

I still think more force twisting the chassis is generated by the motor

trying to dive under the driveshaft and loading up the suspension on

the left side of the car when accelerating rather than the moment of

inertia in the motor.

It also doesn't help that the chassis are inherently unbalanced with the battery down one side and everything else on the other.

[DJTheo]

Yes, unfortunately both phenomena appear and while you can solve the inertial one you can't remedy the torque one.

Cheers

[Wrc action]

Just by a belt drive car and be done with it lol. I would recormend a TA05 as its a great drive, stock settings with some 50wt losi shock oil over teh kit standard gives a real easy and confidence inspiring drive and the ebay prices make it only about £20 more than the TT01. so go on make the jump get the merc one...

[GPZ1000RX]

Club slot car racers started to encounter the torque reaction problem in the mid to late sixties as motor power started to get higher. It was solved by mounting the motor across the chassis, like a belt drive RC instead of inline like a TT. They also arranged the motor so that the torque reaction tries to hold the front of the car down on acceleration and the rear of the car down while braking.

Lap times tumbled!

[Guest joelvardy]

try a aul propshaft that might help

[hellwheels]

I have a C2 Pro motorn (19 turns), Oil Shocks, aloy shaft, ball

bearing, and still it drifts to the left, My guess is that it's just a

design problem on the TT01, so as others have said, if U cant live with

the drift, get a belt driven.