Author Topic: Sheared bolt in the clutch pressure plate  (Read 3700 times)

Offline Drew400

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Sheared bolt in the clutch pressure plate
« on: November 15, 2014, 01:19:02 PM »
Yes indeed, folks. There I am 'tightening fully' (as instructed by Haynes) the four bolts that compress the springs/square plate of the clutch when, snap, one shears off. Oh joy, I say to myself as I briefly contemplate trying to run it with three bolts in place (soon dismissed that lazy notion).

I had already checked to see if there was a torque setting for these bolts when coming across the 'tighten fully' instruction. That instruction says to me, keep going until it stops turning... not a question of trying to then over-tighten it against the stop. No, this bolt snapped before I had to put any real pressure on it with a wrench.

I'm sure that I can source a new pressure plate fairly easily, probably more easily that trying to drill out the bit that's still in there. More importantly, do you have any tips for the torque that should be applied? Is there any danger from under-tightening (which will now be my preferred default approach)?

Thank you,

D.
Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline LesterPiglet

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Re: Sheared bolt in the clutch pressure plate
« Reply #1 on: November 15, 2014, 01:34:50 PM »
I normally just tighten until they seat then a tiny nip-up.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Set/sit. Bought/brought FFS. Bloody Americans.


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Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #2 on: November 15, 2014, 04:22:41 PM »
Thanks Lester,

That's what I though I was doing. Maybe there was a weakness in the bolt.

Cheers, D.

Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline RGP750

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Re: Sheared bolt in the clutch pressure plate
« Reply #3 on: November 15, 2014, 04:30:28 PM »
Quick tip that may get the broken part out.
Drilll about a 2.5mm hole in the centre of the broken part and tap
in a torx bit that is a tight fit, and use a socket on the torx.
 ;)
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Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #4 on: November 15, 2014, 04:56:42 PM »
Nice one RGP... and now I know what those strange little screwdriver bit things are called!

Cheers, D.
Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline Lobo

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Re: Sheared bolt in the clutch pressure plate
« Reply #5 on: November 16, 2014, 06:18:33 AM »
Hi Drew,

Does indeed sound like you had a 'tired' bolt. Time to replace all 4 perhaps?

If wanting to improve the tool inventory the (typical) screw extractor kit may be an option.. just depends on how many more jobs your planning!

http://www.ebay.co.uk/itm/8-Piece-Screw-Extractor-Broken-Stud-Damaged-Bolt-Remover-Set-Easy-Out-Brand-New-/110868152075
 
As you say, finding a torque for the 4 bolts is not easy... the 1st below is for the 750K2 lock nut.

The 2nd pic is for 'generic' bolts from my 750K2 manual... the 4 clutch bolts are 6x20 and the same part # as the K2

Good luck,
Simon
« Last Edit: November 16, 2014, 06:42:08 AM by Lobo »

Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #6 on: November 16, 2014, 09:24:37 AM »
Thanks Lobo,

I may be investing soon and certainly will use a set of new bolts.

Cheers,

D.


Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #7 on: November 16, 2014, 03:02:21 PM »
Update... the offending bolt is out. Was very easy and thus confirmed that I hadn't over-tightened it or else it would have been jammed at the bottom of its chamber.

So, I'm now asking DS if they have a set of new ones and will only tighten them to Lobo's generic suggestion.

Only a slight delay to my project progress.

Cheers all.

D.
Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline hairygit

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Re: Sheared bolt in the clutch pressure plate
« Reply #8 on: November 16, 2014, 03:32:12 PM »
Wel done getting them out Drew, big sigh of relief I'll bet! If all you want is those bolts from DSS, by the time you've added p+p and vat on the lot, it'll be expensive! Try a local hardware store,or even the Robin B'Stards at B&Q, theyre are just normal M6 bolts, 20mm long, easy to find, and cheap!:))

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Offline Trigger

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Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #10 on: November 16, 2014, 05:15:53 PM »
And there's me thinking they're special Honda bolts.

Thanks chaps, all ordered.

D.

Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

Offline Trigger

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Re: Sheared bolt in the clutch pressure plate
« Reply #11 on: November 16, 2014, 05:19:45 PM »
Yes, they are a special Honda bolt. It comes in a Honda bag from DSS and that is what you pay for ;)

Offline Drew400

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Re: Sheared bolt in the clutch pressure plate
« Reply #12 on: November 17, 2014, 08:41:26 AM »
 :D
Previous bikes:Puch Maxi 50, CD175, Suzuki T500, CX500, Z200, GS850, XS1100, GT750 (kettle), RD400, GTR1000 (not too many boastables in there!), CB750F2 Phil Read Replica

 

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