3 or 4 gear cr2

[SHY]

Can anyone show a pic of an external idler?

Btw I saw the Rudebits make a weighted prop shaft or something on the DB1, is that to counter the motor rotation effect? (side torque)

[Gayo]

Originally Posted by SHY

Btw I saw the Rudebits make a weighted prop shaft or something on the DB1, is that to counter the motor rotation effect? (side torque)

Yes, so you don't get torque steer. Maybe that's why DB1 handling seems to be so good (never saw one running yet), the motor doesn't affect front-to-rear balance in any way, on or off-power.

[Gayo]

An idler setup :

[SHY]

Originally Posted by Gayo

Yes, so you don't get torque steer. Maybe that's why DB1 handling seems to be so good (never saw one running yet), the motor doesn't affect front-to-rear balance in any way, on or off-power.

Any close up of that? Must be quite a bit of mass added!

-looks like a serious amout of brass on that axle, very smart!

They also modify the "front slipper diff half" - what is that about?

Some guys did something very similar a couple of years ago, putting a B4 front on a B44 - it was called the B42. Said to be super quick, but only worked on high grip tracks. Of course they didn't do that fancy counter rotating weight thing though.

Does that brass "flywheel" from X-Factory totally eliminate the effect from the motor rotation. And is that a plus on high grip or not?

Originally Posted by Gayo

An idler setup :

Wow, does that really make such a big difference!

[RogerM]

Yes it makes a big difference, think about how much your slipper & layshaft assembly weighs and how far out the mass is from the center of the shaft!

I think you might well be surprised at how little weight has been added to the RudeBits prop shaft.
I can assure you that the amount that has been used would have been accurately calculated based on a lot of parameters and that Dave wouldn't have just plucked a value out of the air! I am afraid that is all I will be drawn into saying about the DB1 transmission as I mustn't give the game away, ask Tony for the rest ... good luck getting the secrets

[ianjoyner]

I think a few people missed the significance of the external idler, here's the configurations listed with the most rear weight transfer (due to power) at the top.

CR2 3 gear (external idler)
X6 / CR2 4 gear
X6 4 gear + brass fly wheel
X6 3 gear

One theory would be that you would go to the top of the list for low traction conditions to get maximum traction out of corners, but I really think this depends on the track / conditions / rest of setup.

I actually prefer the X6 + flywheel in slippier (wet grass) conditions because it smooths out the car through the corner, even though you actually loose straight line grip, it feels better overall. Maybe a more point and squirt track would still be better without the fly wheel.

[fastinfastout]

Originally Posted by ianjoyner

I think a few people missed the significance of the external idler, here's the configurations listed with the most rear weight transfer (due to power) at the top.

CR2 3 gear (external idler)
X6 / CR2 4 gear
X6 4 gear + brass fly wheel
X6 3 gear

One theory would be that you would go to the top of the list for low traction conditions to get maximum traction out of corners, but I really think this depends on the track / conditions / rest of setup.

I actually prefer the X6 + flywheel in slippier (wet grass) conditions because it smooths out the car through the corner, even though you actually loose straight line grip, it feels better overall. Maybe a more point and squirt track would still be better without the fly wheel.

how exactly does a 3gear CR2 with external idler differ from any other mid mount 4 gear in regards to rear weight transfer?

[Wacker 2]

Originally Posted by fastinfastout

how exactly does a 3gear CR2 with external idler differ from any other mid mount 4 gear in regards to rear weight transfer?

with a 3 geared box and external idler gear you have the motor, slipper assembly and layshaft, and diff / wheels rotating in the same direction causing more of a 'kick' to the rear end upon acceleration.

When you have a 4 geared box installed you have the slipper assembly and layshaft rotating in the oposite direction which counter-acts the inertia of the motor - this will reduce the 'kick' to the rear slightly upon acceleration and reduce stability and traction slightly.