Author Topic: Left hand lower frame bolt  (Read 563 times)

Offline rustywheels

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Left hand lower frame bolt
« on: May 26, 2020, 09:23:39 PM »
Yes, THAT bolt...

So a quick question, does this look right? Should there be any gap between the end of the bolt and the case? The PO has obviously replaced it at some stage, and whilst I don't have any oil leaks, it is incredibly tight against the engine case, and yes, it does have the spring washer fitted.  I haven't taken it out, but it looks to be between 74 to 75mm in length, and CMS show it as a 10x74mm.

Probably fretting about nothing. I'm almost tempted to remove it and skim a little off the end.

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Offline Nurse Julie

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Re: Left hand lower frame bolt
« Reply #1 on: May 26, 2020, 09:36:23 PM »
Oooooh, that tight. As long as its done up all the way home and is only just touching the case, it will be OK. But, a few people have done them up too tight and cracked the bottom crank case. I can't remember the full story but I think 1 bolt is shorter than the other on the other side, so just make sure you have the correct one in the correct place. Mike the Bike knows more about it but it had something to do with a longer bolt was needed if you had crash bars fitted but the bolt was too long if you removed the crash bars, or something like that.
« Last Edit: May 26, 2020, 09:38:42 PM by Nurse Julie »
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Offline mike the bike

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Re: Left hand lower frame bolt
« Reply #2 on: May 26, 2020, 10:22:42 PM »
It's possible that the bolt has stretched slightly from overtightening.   I would take half a mil off the end to be on the safe side.  The previous comment about one bolt being shorter is correct,  but it doesn't look short enough.
Punching a hole through to the oil gallery is an embuggerance of the highest order.
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Where's that 10mm socket got to?

Offline rustywheels

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Re: Left hand lower frame bolt
« Reply #3 on: May 27, 2020, 09:46:31 AM »
Thanks both.  I took the bolt out this morning.  Is a non standard bolt as its stainless steel, and measures 74.5mm.  Its grooved the casing very slightly, but no sign of any other damage, so looks like I've been lucky, and I've taken 1mm off the end, so all good.
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Offline SeanFD

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Re: Left hand lower frame bolt
« Reply #4 on: June 01, 2020, 10:34:28 AM »
This interested me as I will, hopefully, soon be putting my engine back in the frame, so I looked up the parts list I have.

This shows the same bolt on both sides; unfortunately it doesn’t give a length though, so it’s good to know what it should be.
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Offline paul G

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Re: Left hand lower frame bolt
« Reply #5 on: June 01, 2020, 12:30:51 PM »
Definitely shorter on the left lower than the right.
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