Clutch disaster

[Oscarmark]

Well, two steps forward then sprint back 100 yards!! My problem with getting my new clutch to operate properly are documented in other conversations on this forum... but basically

New clutch plates (plain)
New friction plates
New springs
New bolts
New adjusters
New bearings
New push road
New RGS type cable
Completely overhauled gearbox

I have been having problems adjusting the clutch so that it disengages and re-engages accurately........ Disengage the clutch (pull the lever in) I cannot select first gear, select second and it immediately stalls.

More fettling.... no first gear, then tap down into second "BANG........." nice big hole in the bottom front of the primary cases with bits of metal and bearings all over my drive!!!!!!!!!!!!

The whole clutch has come adrift, the primary chain has come off and jammed under the crank wheel............

The guy who reassembled my bike after the strip down, he will remain nameless..., clearly has not put the clutch together properly. Now my headache is booming and I need to source a new inner and outer primary plus all the other bits and pieces.

[Motoanimal]

Oh s~*t! Sorry to hear that mate. but before you throw everything away, TIG aluminium welding will probably save those cases and the results can be as good as new, no matter how many pieces there are.

Has the clutch centre nut just come undone? I always lap the centre onto the shaft with grinding paste and then do it up using an air ratchet and locktite! I think you will be suprised by how much you can salvage- don't despair too much mate!

[Oscarmark]

Thanks mate, I am feeling a little better now I have cleared up the mess.... and the positive to come out of this is that at least I know why I couldn't adjust my clutch properly... The push rod was pushing against the whole clutch basket which was moving slightly more each time........ I guess that tab washer was there for a reason!!!!

Very best regards

Mark

[Topdad]

Hi Mark, what a ball ache ! however be glad it happened now not at 60ish could have been extremley nasty. I'd echo what Moto said, look at everything and you'll be surprised what can be saved . Also have a close look at the end of the gearbox check the taper etc and the threads plus nut and was there a tab washer and was it preened over? Can't remember is it a 4 or 6 spring unit ? When I had a six spring one of the things I hated was that I couldn't keep the clutch centre nut tightened didn't know about locktight in the 60's ! I could have helped with gearbox bits but not cases I'm afraid . I'm sure the poeple her will be of help ,keep your chin up ,BobH.

[Topdad]

Sorry Mark typed my previous post whilst you were replying BobH.

[Stephen Foster]

"Oscarmark" , Can You please put a good picture of the damage to the cases for Me to inspect ?
May be able to help You .

Steve..

[a10 gf]

Jez*s, I can imagine the destruction

...clearly has not put the clutch together properly

I'd ask for (demand) some compensation.

[Oscarmark]

Some pics, as you can see the outer primary looks as if it has a previous conviction for a similar incident?

I have already sourced a new inner and I have been quoted £230 for a brand new one?? I really think this is beyond economical repair? The domed part had been poorly repaired in the past.

Thanks guys

Mark

[Motoanimal]

Oscarmark, You know, I would venture to disagree. I think that some work with Helium/TIG would restore this part. I am a complete novice with TIG but I successfully repaired the broken and missing part of my brothers aluminium fork leg on his Honda (*spit*!) ST1100 . Just imagine what someone who knew what they were doing could accomplish! It probably wouldn't cost anywhere near £230.00 either.

I think the main reason that these clutches come loose is because the taper between the clutch centre and the shaft is worn and just doesn’t fit properly. Consequently, no matter how much you tighten it, the centre rocks on the shaft and loosens. Therfore, I don't think you should be too hard on the guy who assembled it (oh, OK sue the b~*tard!) . You need to remove the key and use grinding paste to make sure it 'mates' to the shaft efficiently. I'm not a lover of tab washers as the nuts can still loosen with them. This is the 21st century, why not use 21st century solutions? Loctite is king! And so is the air rachet! ha ha! 

If you have access to even oxy/acetelene, I have used these aluminium brazing rods in the past to great effect: http://www.aluminiumrods.co.uk/

[Triton Thrasher]

Clutch fell off my brother's brand new Triumph T140E, the same way.

[A10Boy]

Something worries me about the second picture, was the bottom bolt ripped out of the crankcases or was it still in place and you have unscrewed it? Hopefully the second, as the front three bolts screw into the crankcase to hold the lot together. Whichever, check the threads carefully.

 

[Oscarmark]

You are quite right, even before the 'incident' the larger bolts on the front edge of the casing were not tightening as they should........ the lower one that you mention still had the bolt in place after the crank case broke, so it was not ripped out. My concern is that the new bolts through the new cases may not get enough purchase to tighten properly. I am really reluctant to remove the engine and have to split the crank to affect a repair.

I understand that these holes go right through to the crank itself??

The shaft from the gearbox with the taper is new.........

Cheers

Mark

[Motoanimal]

Oscarmark, Yes those holes go right through to the crank and if the bolts are too long they will foul the crank web. you can helicoil with access from one side only but you will have to be REALLY careful with the swarf. Maybe a vacuum cleaner with a small bore hose taped in it while you tap and lots of grease on the tap? You could also remove the sump plate and wash it with paraffin after?

[fido]

It is very bad luck to have it do all that damage when the clutch fell off. The clutch fell off my B31 the first time I rode it. It just went about 10 yards then there was no drive, like the clutch was slipping. I stripped it and fitted the clutch on properly and it never gave any more trouble for the next few years I owned the bike.

[bsa-bill]

Something worries me about the second picture

Actually something worries me about the first photo

it would appear much alloy welding has happened in the past, and perhaps the three big bolts were not tightened fully for fear of pulling the weld on the cover apart, perhaps this has happened before