How to make a drivetrain free-er?

[Helgaiden]

My drivetrain seems to not be as free as other B4s ive encountered and it might be causing my motor to heat up more than it should with good gearing, so does anyone know how to fix this? If someone can point me in the direction of a guide or walkthrough on how to do it, that'd be great. Also, if need lube or grease, what would i need?

I have a B4 if that helps any.

[RichieRich]

Well, you could disassemble the bearings, clean out the heavy grease and add a little light machine oil for lubrication. That's what most racers do. Also, you can use a little "lighning lube" from the bike shops on your gears. The easiest thing would be to make sure your pinion/spur gear mesh insn't too tight. Though, I assume you know how to mesh the gears properly.

[JK Racing]

On top of Rich's comments, I add this...

Slowly disassemble the drivetrain, removing one moving part at a time. Then re-check for "free-ness". Start with the CVDs, one side at a time, once both are removed and the trans is still binding, take the trans out and apart, spinning the tranny each time you take a gear out. Once everything is completely disassembled, and you have not found the culprit, I put all my bearings into a glass jar (baby food jars work great for this) and my favorite bearing degreaser/cleaner (I use some citrus based stuff made for inline skates) and shake it really well, and let them soak for a couple days (out of direct sunlight). After a few days, take each bearing out, dry them thoroughly, and then in another glass jar, I soak all the bearings in WD-40. Again shaking (gently, I may add) and letting them soak for a couple days, out of direct sunlight again. When all is said and done, I dry the outside of the bearings well, let them sit on a stack of papertowels to drain. When I am comfortable they have drained (maybe a 1/2 hour or so), I spin each bearing to "feel" how free it is, replacing any that are just worn out, and re-assemble everything. As you re-assemble, be sure to double check and spin each piece as you assemble to insure there is no binding. I repeat the process for my race cars about once a month, and my testimonial, on my XX4, I have only replaced 2 bearings, both in the same rear hub carrier, different occasions. I have been racing the car for the last 3 seasons, the last 2 with brushless power. Now my b4 on the other hand....been through a bit of rear hub and front wheel bearings, probably close to a dozen. I do drive the car a bit harder than my 4wd though.

[Helgaiden]

thanks for the info...

but i got a tight deadline tomorrow so to get the basics of it...

would i take the tranny out, spray off everything with motor cleaner, then spray the diff with WD-40 and reassmble? Should i spray the tranny gears with WD-40 too?

of course id clean all the bearings as well.

[Eau Rouge]

Run the gears in the diff dry—NO WD40.

Lightly lube the diff plates with clear stock Associated Stealth lube using your finger as a spatula—don't lube the balls or the ball races in the center gear. Excess lube is just parasitic drag and it makes a mess.

Pack the thrust bearing assembly with black stock Associated Stealth grease. DO IT! Don't use any other lube here.

Don't over-tighten the diff. Take the time to get the factory recommended setting correct.

Clean out all of the bearings and use a very thin oil in them. WD40 is fine here, but it doesn't last very long.

Shim out everything in the diff so there is no slop. Including the case halves if needed, to reduce the pinch on the internal gears. .010" to .020" motor shims work perfectly here and still will keep the insides clean.

Make sure y our backlash on the pinion and spur is not tight. There should be a little bit of slop or play in the gear mesh, but not too much. Stick a piece of paper between the gears when you align the motor if you aren't sure of how much play there should be.



I have a few other tricks, but I need to keep SOMETHING for myself.