BCG – design error ?

[matic]

I don`t know if this is a common issue, but I noticed that the rear axle has a design error. The gear is a little wider than spacer on the opposite wheel (they should be the same) and if you look at the car from the bottom you`ll notice that rear wheels arent aligned simetrically (the wheel with the gear sticks out more in comparsion to the opposite wheel) so the car has a tension to turn right by default. This isn`t noticable with stock cars, but fet modded or dual cell cars are affected most. So if your modded car doesn`t go in the straight line this could be the reason ….

[micro_Amps]

Yes I have noticed this, and you are right, the high speed cars do have trouble tracking in a dead straight line.
If you were going to set them up properly you would need to slice them up and glue them back together symmetrically.
:)uA

[Pork_Hunt]

I set up my KIT racer to use axels I had modified for char-g’s (to make them truly interchangable), by adding a small plastic shim on the non-geared side. Maybe you could trim down the axel and true up the chassis instead.

[Impreza]

That is a great point matic. I don’t know if cutting the axel would help, but I do like the shim idea since the axel has a screw-like lock on it you could position the opposite wheel correctly. I found this out when putting the pull-back wheels on a bit chassis. I think ph2t has looked at this problem as well???

[jamiekulhanek]

Yeah i noticed this, didn’t really think it would make a huge difference.

I wonder if the SBCG has the same problem.

[DaveF]

I wonderred about this one before, especially when people talk about the drift wheel favouring donuts in one direction. A design fault to be sure, and one that could have been easily rectified with a spacer on the non geared side, though this may have meant having to provide extra plastic to the chasis all along that side, and perhaps moving the PCB over a little, and thus perhaps changing the ballance of weight, thus creating another problem.

[jamiekulhanek]

Okay, i had a close inspection and found the the wheels are actually in line, the rear motor pod is offset to make sure the wheels are inline, see for yourself.

It torque steers because the gear is on the left side.

[matic]

Look at your car from the bottom, try to visualize the lines going along the edges of the chasies towards the wheels. If you can`t see the difference than there can be 4 reasons:
– I need glasses
– you need glasses
– All of my axles have the same mistake
– All of your axles are misteruously well done

And I think that gear being on the one side has nothing to do with steering

[Impreza]

someone will have to break out the callipars and a ruler. matic, the torque generated by the motor is thought to effect the path the car takes. The cars (seen alot btw in clones ftmp) tend to travel in a large arc as a result of power being applied to the left rear of the car only. Since these cars have a small wheelbase the torque of the high rpm engines would have a factor on the path the car takes.

Some one else will be able to give you a more scientific explanation I am sure. My physics is limited to early University:blush:

[Impreza]

I could be dead wrong as well?? anyone?:dead:

[micro_Amps]

I had another look and I’m beginning to agree with Jamie, the rear end has a cut-out to accommodate the drive gear, but the rear wheels look to be inline with the fronts.
Im not sure why I thought they were offset, I might have a clone like this in my collection.
:)uA

[matic]

Thanx Impreza for info, I will check again when I get home.

[matic]

I did checking on MS pro out of the box, brand new and here are the results: Axle has a little space so it can be moved left to right. If you press the “gear side” wheel the axle IS alligned, but if you press the other wheel axle ISN`T alligned. I think that torque has a tendency to “pull” the gear-side out causing the car to steer. So if I draw a line under all, the axle ISNT SIMETRICAL ant this was my basic point.
Any other thoughts are wellcome…

[Author]

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