Knackered Clutch Hubs

Aren't clutch hubs especially hardened? The tangs on the friction plates rattle around between the hub splines and carve out unsightly notches. Over time the notches get so bad the plates can stick in them.

What's up with that? Despicable behavior.

Any way this can be improved?

Possible to pay more to buy hubs that are more hardened so no notching?

The later clutch centres are suppost to be hardened but there is a lot of crap on the aftermarket. My advice if you want to buy one take a file with you if it does not affect the metal its good, if it does the centre is to soft.

1up3down said:

Aren't clutch hubs especially hardened? The tangs on the friction plates rattle around between the hub splines and carve out unsightly notches. Over time the notches get so bad the plates can stick in them.

What's up with that? Despicable behavior.

Any way this can be improved?

Possible to pay more to buy hubs that are more hardened so no notching?

Click to expand...

The newer fiber plates are not as detrimental to the center as the sintered bronze are and there are 2 centers available, hard and not-so-hard. If however you have the fiber plates then the notched up center got that way before.
And yes, most despicable!

this is one reason why I WILL NOT use the bronze plates. some FOOL'S want to get rid of the OE 750 surflex fiber plates and IMHO these are THE plates to use over ALL others. look for these or ANY other plates BUT the bronze.

1up3down said:

Aren't clutch hubs especially hardened? The tangs on the friction plates rattle around between the hub splines and carve out unsightly notches. Over time the notches get so bad the plates can stick in them.

What's up with that? Despicable behavior.

Any way this can be improved?

Possible to pay more to buy hubs that are more hardened so no notching?

Click to expand...

Hardened type only.Pick it up and "strike" it with a wrench to listen for a ringing sound ,that's the hardened type.Filing it to remove notch grooves only a temporary fix.Sintered bronze plates are the worst notching culprits for sure.Hard riding say Hobot style will promote notching too.Fiber best.Hope this helps.Peter.

I just got a new center from Old Britts. The picture doesn't show it well but the outer section has been heat treated. Those lines are signs of a heat
affected zone. It is harder than the old one, a file skimmed across it where on the old one it took a bite.

What you got from Old Brits is called a "Genuine Norton Factory Part" from Andover Norton, and I am not surprised- Ella and Fred tend to sell you the real thing. Ever wondered why there are different prices for the same part? Because there are different qualities.......... but not from us.
Joe Seifert

rpatton said:

I just got a new center from Old Britts. The picture doesn't show it well but the outer section has been heat treated. Those lines are signs of a heat
affected zone. It is harder than the old one, a file skimmed across it where on the old one it took a bite.

Click to expand...

Thanks for taking the time to post that, I have a similar hardened hub and was about to waste time disassembling it to file the notches out...am now going to change my bronze clutch plates to Barnett instead and see how it goes (the notches are not too bad yet so hopefully I won't need a new clutch hub)

I've always preferred the bronze plates on my race bikes because they never seemed to fade, no mater how much I slipped them at the start, and never seemed to wear out. But I have to admit that they do wear the hubs noticeably faster than the fiber plates, and I ended up occasionally replacing the centers. When I started racing I used stock plates, and later Barnett plates, or combinations of stock and Barnett, but when the bronze plates came out I was sold on them the first time I used them. I've got nothing against the fiber plates for street bikes, or even race bikes if you replace them as needed. I just liked the bronze ones better for my applications. A really nice product would have been alloy plates with bronze friction surfaces, like I use on my Rotax engines, but I've never seen them offered for Nortons.

Ken

Hi Ken

Same as you loved the bronze plates. However found on the racebike coming out of haipins they were too good & came in with a tug. I tried mixing with other plates to ease the take up. Now sold on fibre surfix plates all with belt drives.
The roadbike however will be on bronze for ever as, I have plenty of spares that just don't wear out.

Chris

ps 4 Knackered centres (Norvil) so stated fitting Steve Maney ones but will, in the light of ZDF's comments source from Andover.

I don't know if it is typical, but on my 5 plate 850 clutch the three central ones notched the hub while the top and bottom plates barely marked it...so if I get into mixing types I'll put the bronze plates at the top and bottom (but am going to see how a full set of Barnett plates work first)