Weird clutch

[Worty]

Tab washers aren’t very good in this application.  Loctite is needed.

Cheers TT, it'll get the business.  When I bought it, the nut was finger tight, but it did run for 000s of miles with no problem after the first 'rebuild' by RM (perhaps the only thing he got right).  However, when I took it off for the Berger Build, it wasn't very tight then.  Little wonder the clutch was not good with how loose it was

[berger]

worty you need to blue up the shaft and have a look for contact within the tapers

[Swarfcut]

   Adaptor with internal thread and mention of rollers indicates the superior (compared to earlier 6 Spring) Triumph 4 Spring Clutch.

   With both clutch types it is essential the mating tapers are correct, and blued up a la Bergs is a good ruse. A dab of grinding paste to lap them was an old trick, The drive is carried by the tapers, not the key....make sure this locates and does not foul the adaptor.* Too loose on the nut will shear the key and often damages its location in the mainshaft. This is of no real consequence, but as mentioned tab washer is more often ineffective, loctite and a clutch locking plate, breaker bar or rattle gun to get that centre nut good'n tight should do it.

 A clutch centre extractor should be required to remove a correctly assembled centre. From experience make sure the adaptor will fit the extractor before assembly. The threads on both may need a fettle, easier to do on the bench.

 Swarfy.

 * Additional. See further later comment about the key by CB...That's what I meant to say!  Pattern parts are notorious for being not quite correct, hence care needed to ensure the tapers match.

[Worty]

   Adaptor with internal thread and mention of rollers indicates the superior (compared to earlier 6 Spring) Triumph 4 Spring Clutch.

   With both clutch types it is essential the mating tapers are correct, and blued up a la Bergs is a good ruse. A dab of grinding paste to lap them was an old trick, The drive is carried by the tapers, not the key....make sure this locates and does not foul the adaptor. Too loose on the nut will shear the key and often damages its location in the mainshaft. This is of no real consequence, but as mentioned tab washer is more often ineffective, loctite and a clutch locking plate, breaker bar or rattle gun to get that centre nut good'n tight should do it.

 A clutch centre extractor should be required to remove a correctly assembled centre. From experience make sure the adaptor will fit the extractor before assembly. The threads on both may need a fettle, easier to do on the bench.

 Swarfy.

Thanks Swarfy, will give all of that careful consideration along with Berg's suggestion.  I'm going to do some testing on the taper prior to reassembly as the current arrangement has never necessitated the use of an extractor - just came straight off.  The key has got some battle scars, as has the slot in the mainshaft, but it does work well if the nut doesn't come loose.  I have a locking plate, Loctite, a massive ratchet set (3/4") and a strong right arm -  I'll be making sure it won't come loose easily!!

[chaterlea25]

Hi Worry,
The suggested 70 Nm is only about 50lb/ft
It needs to be 65-70 ft/lbs
Or as other suggestion a good rattle gun

John

[berger]

worty it is no good rattling it up if the taper isn't doing it's job, would you trust your car steering tapers if the nuts kept coming loose 

[Worty]

worty it is no good rattling it up if the taper isn't doing it's job, would you trust your car steering tapers if the nuts kept coming loose 

Don't worry mate, I'll be testing the taper thoroughly, and have my eye on some grinding paste.  I take it a coarse paste if it's bad, followed by a fine paste to finish. 

[muskrat]

G'day Worty.
I can't condone grinding paste to do the job. More than likely to alter the shaft taper than the offending part. If that is done it'll bugger a good shaft for life. Making further  fitting new parts a PITA s well as stuffing the next owner.
If it were me I'd take it to a toolmaker with a tool & cutter grinder to do the job.
Cheers

[berger]

if it were me i would ----------------- go to the pub . ------ or blue it and fine grind it to get a better fit than it is now , then check chain alignment and goo the nut on and ride it , i also wouldn't give a damn about the next owner because i wouldn't sell it. if rivet man can do what he did with worty's engine i wouldn't be concerned about a gearbox shaft and clutch adaptor that are readily available just in case someone else gets the bike, but that's me after having my fingers burned with nearly everything i've bought.  now where was i? oh i know watching news a 10 

[muskrat]

G'day Bergs.
Yes I know I was being too technical.
I get your drift.
Cheers

[CheeserBeezer]

An issue i've come across is the parallel key which locates the adaptor on the mainshaft is too deep. This prevents the tapers mating with each other. File the top off the key so that there is only 1mm protruding above the mainshaft along its length.

[Worty]

An issue i've come across is the parallel key which locates the adaptor on the mainshaft is too deep. This prevents the tapers mating with each other. File the top off the key so that there is only 1mm protruding above the mainshaft along its length.

I get that logic CB - makes good sense, I do think the key does sit more proud than 1mm.  Y'see, it's a good idea to get a range of opinions, that's what this Forum is so good for!  Musky, no grinding paste then and Bergs, yes, yes, the pub!!!!  I'll post piccies of the chainwheel soon for an opinion - seems to have notches on one side of the teeth - can see the wallet getting lighter.

[Worty]

Oh, and I ain't goin' to sell it, but I do want to kick it round the garage at times

[Worty]

Right guys.  Have done what CB said and filed key down so that about 1mm protrudes above the mainshaft - unfortunately, even with the filed down key, the centre won't tighten against the taper.  If I remove the key and try the centre, it starts to grab the taper if I twist it a bit, but that means that the key doesn't line up.  The pictures show the key recess a bit chewed up, and the condition of the chainwheel which has a small burr near the top of each tooth (on what I call the 'leeside' of the tooth - the bit that doesn't have the force of the chain against it in drive).

I'm hoping that this is fixable without removal and machining, or vast expense - otherwise it's off road until further notice.

[groily]

Hmm. I'm trying to see a taper on there. Maybe just the camera, but looks a bit on the parallel side to me. Which wouldn't be so good.
Here's a pic of a (worn) s/arm 'box mainshaft I pulled to make new sleeve gear bushes for comparison  . . . Others will have better examples.
But I don't get a good feeling  . . . Hope someone can come in with a dose of optimism though . . .