Could you drill holes in an OEM inner clutch hub??

[nikki]

I have had a little clutch problems with shattering plates lately so I am switching to a Hinson outer basket and Hinson friction plates. The Hinson outer basket will help keep the clutch cooler by allowing more oil flow because it has open slots in the fingers.

Question is...

Could I drill small holes in an OEM inner hub to make it similar in design to the Hinson inner hub? The Hinson has three small holes in every third groove. If we drilled from the inside (where plate sits) there shouldn't be any roughness on the hub where the plates sit (if there is a little, we can file it and make it smooth).

Has anyone tried this in an inner hub? I have heard of people drilling holes in OEM outer basket fingers.

Thanks for any help!

 

[mxneagle]

we were doing it on 2000 yz426's to help with the chatter in the clutch do to it running dry. It helped a little and we had no ill effects.

 

[ochster]

I have done this as well, with no problems.

 

[nikki]

Thanks for the replies, guys. I think we're going to give it a try.

Do you do the same as Hinson - 3 small holes in every third groove?

Has anyone else drilled holes in an OEM inner hub? Any possible problems/tricks to watch out for? Thanks again!

 

[cr-man]

I have drilled holes in the inner hub before I put two holes in each lower spline. Eric has this in his book he says to drill one or two holes in each spline. You might want to change your clutch bearing and bushing (as a set) they might be worn out causing you to break clutch plates. Just a thought! Good luck!

 

[Pete Payne]

Also be sure that when you drill the inner hub you don't want to drill into one of the supporting webs or the threaded tower for the springs.. Good Luck !!

 

[TFR]

Yes, Drilling holes in the inner hub helps the oil flow. I do this with Suzukis and Yamahas especially. Hondas already have them in theirs. I usually drill them like this: 2, 1, 2, 1, etc. all they way around. When I drill the two holes I put one low and one high(not to close to the edge). The single hole I drill in the center. It is a good idea when installing a Hinson basket to replace the inner hub with a new one. Also a new clutch is a must. The tabs on your old plates will be worn even if the fiber surface still looks good. If you don't do this your Hinson basket will not last.

 

[nikki]

Great! Thanks for all the good info! :)

Yep... we're replacing everything - new Hinson outer basket, Hinson friction plates, OEM inner hub, pressure plate, steels, springs, bearing, spacer, washers.

 

[Shawn Mc]

If your spending the money on Hinson parts, do yourself a favor and buy the Hinson inner hub too. I did, and Ill never regret it. The steel bushing came loose in the stock unit. I never would have known but the clutch felt funny- kinda grabby. I checked it and it was flopin around like a fish outa water. (2000 YZ426)

 

[jfisher304]

Kinda changing the subject a bit, but I just heard of something that made me wonder. There is a group out of Houston that is nickasilling the hub and steel drive plates. They claim a longer life span an better feel....anyone ever heard of doing this?????

 

[motometal]

Do the steel drive plates wear out? I don't think I have ever had to replace them. Just the aluminum ones. The harder the plate, the more slippery it is. I would not recommend hardening the steel drive plates on the friction surfaces. Hardening the hubs where the plates slide would help.

When drilling holes, chamfer the edges...don't leave a sharp edge. Sharp edges are where cracks usually start.