I checked the primary chaincase to find it overfilled with very watery & thin emulsified oil.
On examination I can't see any oil coming from the crankcase & why would it emulsify? The cush drive nut is tight & I can't detect any play in the main bearings. Is it possible to detect play in the mains by grasping the cush/ crankshaft end?
Grabbing the clutch cover, I can move the whole clutch a bit less than 1/8" in & out.
The bike recently did about 30 miles in fairly heavy rain. That's never caused problems before.
Does any of this indicate a known problem? Happy to see any thoughts.

I'd say definitely, water has got in. Just drain and refill and check next time you ride in the rain. Ron

email (option): ronpier@talk21.com

If you have 1/8" end float at the clutch/mainshaft that should be investigated...There should be effectively no end float...Ian

email (option): ian@wright52.plus.com

As Ian said ! Or the clutch center nut is coming loose? It happened to me on my Special once on a ride out to the Purbecks. I made it to about a mile from home before I had no clutch at all and far too much traffic to risk riding without a clutch.:confounded: Ron

email (option): ronpier@talk21.com

Thanks for the replies.
I've taken the plates out & found the play.
When the driven clutch centre is pressed up against the clutch sleeve, the outer driving chainwheel has the play, sliding back & forward on the sleeve.
I don't want to dismantle further before getting opinions?

Bob if the sleeve and nut 62 is tight on the main shaft, there should be no end float. Likewise with the plates and main spring installed, there should be no movement of the clutch on the sleeve spines.

Somehow it seems that your clutch center is not fully on the spline? Ron

email (option): ronpier@talk21.com

Ron
Thanks for the swift reply.
I've briefly checked the sleeve nut, which seems tight. The clutch has never given trouble slipping on the taper.
I'm going to have to take the whole clutch off, I think. That'll be in a day or so. Wedding anniversary tomorrow.

I've found the problem. The outer chainwheel's* broken. The machined inner bearing ring fitting the clutch centre has separated from the chainwheel itself allowing it to flop around. I've got a new clutch, wondering whether to repair or replace. The chainwheel teeth & clutch plate facings aren't real flash but the rest of the mechanism's OK.

*using Draganfly's terminology.

Personally I'd replace it with the new parts and if the old one is repairable? it could be done at a later date as a spare under the bench.

Ron

email (option): ronpier@talk21.com

Ron & anyone else reading

The NOS clutch has been paraded for inspection. Many components are covered with thick paint which I'll remove before assembly.
I need the nuts securing the pressure plate & the screws securing the clutch cover.
I make these
Nuts 1/4 BSW/ Cycle 26 TPI
Screws 3/16 Cycle 1/2" length. The screws on the old clutch are a cheesehead type.
Have I got the measurements OK?

Draganfly will sell you 2BA x 1/2" screws for the bowler hat. They sell the same screws for the primary case. Not quite right but probably all that's available unless you make them.

Nooky Nuts is cheap for BSC fasteners. British made zinc plated or SS. Ron

http://www.nookysnuts.com/catalogue/fasteners/brightzincplated/nutsandbolts.html

email (option): ronpier@talk21.com

Bob, the nuts securing the outer clutch plate were 1/4" Cycle - 26TPI. Original part number EB113.
The screws securing the top hat cover were 3/16" Cycle - 32TPI x 13/32" long. Original part number EB379 in the parts list I have.
I am not sure about the original head shape as none of mine are original but I'm guessing cheesehead or fillester would be original.

I'm not sure if these 3/16" cycle are available in your part of the world but 3/16" cycle are unobtainium where I am.
You can get away with 2BA which are slightly smaller in diameter and a whisker different on pitch but close enough to work.
I have had good luck substituting 10-32 UNF which 60 degree threadform, 32TPI and a whisker bigger in diameter. In practice with manufacturing tolerances I have found they are a better fit compared to 2BA.

Ron & Ray
Thanks both for this information.I'll start looking locally first. Of course, if necessary I can transfer the fasteners from the old clutch.

After blasting the new clutch has some corrosion which some bastard painted over, but it should come up OK. The ball bearing in the pressure plate is seized, WD40 soaking & tapping won't shift it. My manual doesn't specifically mention this part, but from the sectioned drawing it looks to be a sealed unit. The Draganfly exploded view doesn't list this piece as a separate component. I can re use the original pressure plate, but any ideas about how to loosen the ball bearing up?

Probably soaking in a tub of diesel for a day or two and some gentle heat from a blow lamp. Although I doubt it makes much difference if it moves or not? Ron

email (option): ronpier@talk21.com

If the ball really refuses to budge you can drill a small hole in the outside end of the fitting that the ball sits in. Then use something suitable to tap the ball out, such as a pop rivet shank or similar...
Fit the ball back into its holder with some grease...It can't go anywhere once the pushrod is fitted...

As Ron notes it doesn't matter if the ball doesn't move...It just provides a hardened point contact for the pushrod....Ian

email (option): ian@wright52.plus.com