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No one else makes a dry belt clutch that fits a Royal Enfield gearbox, so it was out of desperation that I bought this very expensive clutch from Bob Newby £410+post+vat. Yes I have saved a lot of cash by not buying it from Hitchcock's at £520+post+vat, but a second hand job of any make and about £100 would have been closer to what I was looking for. On the plus side Bob did tailor make the system to suit my bike, thanks Bob.

So what's special about this dry belt clutch, well from what Enfield owners have said it certainly works better than any Royal Enfield clutch, which is what you would expect for that wodge of cash.

But please let me cast a critical eye here, a large number of people have bought these clutch's and you who have bought them obviously want to feel completely happy with them, and I must say this is just my opinion and I don't want to upset anyone especially Bob Newby.

Ok, here's what I don't like about the clutch:
1) It's noticeably heavy, certainly heavier than other competition clutches I've had.
2) It doesn't spin freely, quite stiff to turn by hand.
3) It doesn't have shock absorbing rubbers or springs like a modern clutch (not that it's that important, but this is the 21st centaury), the belt does help take up the shock, but is that a good thing for the belt?
4) The bearings are not a sealed race but individual bearings which run directly on the clutch centre, dare I say UK weather and rust.
5) The steel plates are just that, steel, and how they rust! I'm also starting to hear people talk about the steel plates warping, "not particularly well designed" "be prepared to fit new plates regularly."

The steel clutch centre has a flange that rubs on the back of the steel bearing seat inserted in the back of the alloy drum, steel on steel, no bronze bush etc. There's also an alloy ring at the back of the clutch that holds the whole thing together, this also rubs against the steel clutch centre.

My conclusion is; this clutch is perfectly good for racing (for which it was probably intended), but I doubt that it is any good for road bikes unless it's a wet clutch. Only time will tell I guess, but I look in to my crystal ball (pint) and see the mist clearing to expose a lot of expensive re-builds in the future.

Bob Newby recommended grease to use with the bearings is Castrol Spheerol B2.

Thermmaplex grease is also looking good for this clutch.

Castrol did recommend Tribol grease, however it is no better than bog standard grease.

 

Apparently the recommended grease is good for 10'000 miles, I don't know why we are not told this when we buy the clutch. Thanks to Stuart for the information.

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1000 miles with Castrol recommended (Tribol) grease

It's 1000 miles and the clutch is back off the bike, the first thing that I noticed after taking the plates off was quite a bit of sideways movement or bearing float to the clutch centre. When the clutch centre was pushed in or backwards, it was easy enough to turn but with a horrible metallic scraping sound. When the centre was pushed outwards it met with a fair bit of resistance.  

The second thing I couldn't avoid noticing was that the three hexagon screws at the back of the clutch, they rounded off very easily when trying to remove them. The hex screws are soft steel and the hex is very small, there is no tab washer so a drop of thread lock is a sensible thing to use when you consider that the three screws hold the whole clutch together. The clutch now in bits and the wear although slight was obvious, predictable and is ongoing

Even if the bearings were lubricated properly, I'm sure this clutch would still drag due to the steel centre rubbing on the un lubricated steel bearing insert, and alloy ring.  A thin bronze bush each side would have helped.      

 

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500 miles more

After finding some Castrol Spheerol B2 grease (a discontinued product), I have stripped, cleaned and rebuilt the clutch. With the thought clearly in mind that I have used the makers recommended grease and all will be well from now on, I took the bike to the 2010 Bulldog bash. The weather was miserable, raining most of the time, but the bike including the clutch worked flawlessly, although a heavy lever operation, and it led me to ask myself if I had been a little too harsh in my criticism of this clutch. I got the bike home and started to wash the Bulldog mud off the bike, taking care not to get too much water in the direction of the clutch.

The answer to my question regarding criticism of the clutch came only two days later when I tried to move the bike. The clutch had jammed up solid, I'm guessing that the steel plates have rusted to the friction plates.

I did notice that the Castrol spheerol B2 grease does fly off the clutch just the way the Tribol grease did, this does not fill me with confidence, but we shall see.

As I will soon be taking the bike some 1300 miles to Germany and back, and given the track record of this clutch I would be a fool to just free those plates and not rebuild the clutch completely. Can you imagine rebuilding this thing at the side of the road or even in a camp site?

I must point out that this is a dry, semi open, belt primary, and the problems that I have encountered shouldn't happen if it were used in sealed primary cases and run in an oil bath. However this was sold to me as an open belt primary.

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Please note, clutch adjustment

Bob Newby recommends half a turn out of the pushrod adjusting screw.

If you are using a Royal Enfield gearbox that has not been modified with the new Hitchcock's outer cover,

or been modified as per the Royal Enfield clutch page of this website, then this adjustment is not possible as the gearbox outer cover flexes taking up any adjustment in the clutch.