Help adjusting my DB01R diff

[kolbaldt]

Hi!

Bought myself a DB01R kit, and the 501 metal diff halves, did abit of reading and searching on this forum before assy the diffs, but all the treads i could find said the same: one hand on the pulley, one on one of the wheels, and then tighten till you almost cant turn the last wheel.

When i try the above (first i tighten my slipper all the way in) i think it is VERY easy to turn the wheel, if i try tighten the diff any more i "lock" the diff? (when turning one wheel the opposit turnes the same way)
How much "force" do you need to apply when turinng the wheel when the spur and opposit is locked?

regards michael

[94eg!]

Originally Posted by kolbaldt

Hi!
...if i try tighten the diff any more i "lock" the diff? (when turning one wheel the opposit turnes the same way)

You need to hold the front tires or spur from turning when checking your adjustment. If you have a brushless motor, it won't hold the drivetrain steady against a stiff diff like a brushed motor. If you have a brushed motor, perhaps your slipper is set too loose. Try placing your front tires on the table when checking your rear diff...

[simoncrabb]

How I do it:

1) With diff out of the car (ie just built), put screwdrivers in both outdrives, and then try to turn the pulley by hand. When it's just impossible to turn, it's probably tight enough.

2) Diff in the car I hold the spur (with slipper done up tight) and one wheel (or a driver in the diff outdrive if you've got the wheel off to adjust it) and turn opposite wheel, should just about move, almost impossible.

3) Set slipper to just slip, so it slips before the diffs when holding two front wheels stationary and turning rear wheels together.

4) Final adjustment check on track, full power acceleration should slip the slipper for 'a few feet', and the diff shouldn't be slipping. Learn the difference in noise between the two!

[94eg!]

Originally Posted by simoncrabb

3) Set slipper to just slip, so it slips before the diffs when holding two front wheels stationary and turning rear wheels together.

This absolutely won't work.

If you held the front wheels, the slipper can't possibly slip. The two center pulleys are locked together. If you do get the belts to turn with the front wheels and spur locked, your slipping both the slipper and the front diff. Your just messing up your front diff and your slipper will seem tighter than it really is...

This = FAIL!

To test the slipper's function, you hold the spur and one rear wheel steady. Make sure the front wheels are in the air, and turn the other back wheel. The belts should turn and so should the front wheels when you do this. Then you know your diff is set tighter than your slipper.

Typically you shouldn't have to repeat this step for the front diff because it's usually set tighter than the rear. If like to run both your diffs the same, then definitely check the front diff as well...

The trick is finding a combination of slipper and diff tightness that works well on the track. If you set the slipper too loose before you drive the car, you may run into trouble with your diff when you try to tighten it. This means you must start the process over...

[DaveG28]

Having struggled for a long time with diffs the way I tend to do it is:

1. Set the diffs outside the car as previously suggested (screwdriver in each outdrive, check you can't turn the pulley by hand).

2. Install in car, and set slipper comfortably too tight so it won't slip

3. Run in diffs for a min or so (turn car on, hold with say left hand wheels on the ground and right hand in the air and run at medium throttle, then repeat on the other side)

4. Practice starts on a high grip surface (I use carpet at a track or some spare in my garage) and tighten diffs half a turn at at time until you no longer get slip.

5. Progressively loosen the slipper until you get a little slip from that (although I tend to run mine very tight still)

Might not be ideal but it removes the question of whats causing the slip!

[kolbaldt]

Hi everyone!

Thanks for the answers! havent had time to try it out, but is it normal that when you tighten the diff up, it starts spinning thee wheels the same way at some point??
I mean if i turn one wheel now, the opposit turns the other way, but if i thighten any more they start turning the same way.. isnt this too tight or is this normal?

regards michael

[94eg!]

This is typical when using a brushless motor as they don't have can's magnetic feild or brush tension to hold the rotor from turning. It's also typical if you have no motor installed at all. I would say it's not typical if your using a brushed motor...

If you need to check your diffs tightness but both wheels are turning the same direction, simply lay the front wheels on the table. Then the drivetrain can't turn when you try to spin one rear wheel...

[kolbaldt]

I Dont have any motor installed yet, just affraid i overtighten it or its to loose

[T4miy4 Guy]

Just follow the manual or read some other diff posts on here they explain how to build the diffs correctly....
Heres the image from the manual on building the diffs

Originally Posted by dimblum

Here are Tamiya's answers to your questions:

1. Use diff grease to attach the rings to the diff halves. The rings will not slide against the halves. The metal will create it's own friction under pressure.

2. I think I know what you mean about the thrust bearing. It should be inserted with the flat edge away from the center of the diff so that the head of the screw has the most surface area to grip onto the thrust bearing.

3. There is no need to put additional diff balls in the three extra holes in the pulley. Those holes are reserved for attaching a front one-way.

4. The Tamiya method for tightening the diff has been mentioned before in the forums. Tamiya shows this method with a slightly confusing diagram in the DB-01 build manual (shows the diff with two parts locking the arms - an arrow - and a "X" symbol). Basically you put two small allen keys between the slots in the diff arms, hold the diffs in your hand (grabbing the allen keys to lock the arms in place), then you try to rotate the pulley toward you. If you can rotate the pulley while the diff arms are locked in place, then it is too loose. Keep tightening the diff screw until you can no longer turn the pulley by force.. This is about perfect for your diffs. Overtightening can be bad, so stop once you can no longer turn the pulley, then insert the diffs into your DB-01.

Hope this helps.

[kolbaldt]

Hi!

Thanks, just been trying to adjust it according to the "original" drawing you posted, its so tight i cant turn it with a finger, but still turn it by "force" if i use 2 fingers, so hope this will work good..

Thanks for the help!

regards mik

[jimmy]

You shouldn't be able to turn it at all using 2 fingers and all the force you can possibly muster. If you can, it needs tightening.

[kolbaldt]

But if i tighten it any more i "lock" it (so both my wheels are turning the same way when mounted in car) and they should not do that should they?

[94eg!]

Originally Posted by kolbaldt

But if i tighten it any more i "lock" it (so both my wheels are turning the same way when mounted in car) and they should not do that should they?

FOR GOD'S SAKE MAN, PUT THE FRONT WHEELS ON THE TABLE BEFORE TRYING TO TURN IT (WHEN IN THE CAR)!!!!