ChitownRC

I dont know if you can really tell from the pics but these are the bevel gears that were out of the front of my buggy. They are all chewed up like they werent meshing with the diff right and there was metal shavings inside the diff case. Basically, they were very sharp and would make grinding noises and stuff when i would go. I know i need to shim the diffs but im not sure exactly where to put the shim. Anyone know exactly?

Thanks

it depends on alot of things where the shims go depends on warpage of the diff case and wear on the gears. how are the gears on the diffs.

What do you mean? The whole diff and all the gears part of it are fine. I did notice the bearing that the bevel gear rides on was sliding out easily, maybe the diff case is messed up a little bit?

possibly...

I only know this because I've shimmed rear-ends in real life.

You gotta put the shims in front of, or behind like the ring gear, to control how close the ring gear is to your pinion gear

hard to explain, without showing, there there should be a shim you can get. Its like your clutch bell actually...

shim here,|o or here, like,

the heres are where your bearings are...THIS is terrible but its the best way I can explain it. either way you're kjust controlling how close the ring gear is to the pinion gear. | = ring o = pinion. LOL

so bad...>_< embarassed

Ya i didint rly understand any of that lol

If you look close you can see shims in this pic:

Its where you need to put diff shims to adjust gear mesh.

http://www.bigbigplanet.com/rccars/v2/v2_02.jpg

heres an article about it too.

RC411 :: Learn How To :: Shim A Diff

O so u dont shim between the bevel gear and the bearing coming into the case??

motoxer4life Wrote:O so u dont shim between the bevel gear and the bearing coming into the case??

You shim both of them.

You need to make sure that the mesh is centered, which is why you shim the pinion forwards and backwards. (Like a clutchbell)

And you also need to shim the outdrives to control how close the mesh is. There should be a tiny amount of play. If there is no play there will be plenty of friction and heat, which will wear the pinion/bevel gears out quickly.

Its all done by feel, much like the article rights. Too much slop and it will wear out quickly. To little free play and it will also wear out quickly. Its hard to write it down here, it best if you ask someone in person so they can show you the amount of play there should be between the pinion and bevel gears.

Kinda like learning how to shim a clutchbell, or setting the mesh between clutchbell and spurgear.

so you would put the shim between the bearing and the diff cup?

motoxer4life Wrote:so you would put the shim between the bearing and the diff cup?

It all depends on what needs shimming. The reason this is so difficult to explain is that the tolerances are different for every car, even of the same make and model. Wear and tear changes it. Shimming the diff cups moves the diff laterally (left to right). This controls how close the teeth mesh.

Shimming the pinion move the pinion longitudinally (front to back). Most times you will not have to adjust this, but occasionally you might have to. Avoid it for now.

The best I can say is read the article posted by J-dub. It explains it in more detail, and it has pictures of the components.

If you want more detailed information look up info on how to shim a full size cars differential. That will give you more detail than you could ever hope to use in an RC. If not, your best bet is to ask someone in person the next time you are at the track.

Alright i will, thanks alot guys

on the mugen..DO NOT put a shim between the pinion and the bearing, only put them over the outdrives(inbetween the bearings and the diff case) when you shim it make sure it spins frely thru the whole rotation AFTER you put the front of the diffcase back on.

Alright thx