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Bizarre Exhaust installation Issue LM1

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simonnorthroad View Drop Down
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    Posted: 15 Jul 2019 at 15:00
Then latest exciting instalment of my round-barrel LM basketcase buildup.

When I install my Keihan downpipes,there is not nearly enough stud protruding to even get the exhaust nuts started.

Ive got tthe proper LM flared split-colletts with the flares seated in the grooves of the finned clamp and the other end of the collets butting up against the header flange but when I offer it up, Ive go no stud thread proud enough to put the nuts on

Ive had to unwind the studs out till they are only, perilously, held into the heads by a few threads to be able to put the exhaust nuts on.

The Keihan headers seem as well made as ever and the collets are correct and installed correctly, is this a common issue?
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GuzziPaul View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GuzziPaul Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 16:11
Have you checked the header is seating all the way down without the collets in. I only have standard headers, but sometimes when refitting them they do seem to stick out ab bit more than normal making the nuts hard to get started.
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Brian UK View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 16:31
I would agree. Make sure the header is fully seated. Under no circumstance should you try to pull it in with the nuts, you risk pulling the studs out of the head.
I assume you don't have the silencers fitted.
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Barry View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Barry Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 17:01
I had that issue when I fitted Keihan downpipes to a 1000SP - and ended up getting longer studs. It was, and remains, a mystery.

Something suggested to me then (which wasn't applicable, in my case) has a PO used 'crushable' washers with their old downpipes, leaving the crushed part still in the head?  Likely not, but worth a look! Others have reported oiking more than one old crushed washers out of their heads.
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Dave P. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 17:46
Yep,seen that one on Laverda twins.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Jerry atric Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 17:56
And on my Cali
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Oldrat Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2019 at 18:43
I’ve seen two sets of gasket rings fitted. Good luck 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2019 at 11:35
The studs on my V50 are on the short side as well. If I was in your position, I'd just get some longer ones. I'm not normally a fan of all-thread but that (in stainless) might be a solution.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BondEquipe Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2019 at 13:06
Old exhaust gaskets can look like they're part of the head until you really dig them out.  Been there . . .
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2019 at 15:46
What he said. Or, the keihan  flanges are too thick? Do you have stock MG ones to compare to?


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Post Options Post Options   Thanks (0) Thanks(0)   Quote jpc Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2019 at 19:19
I have a few roundfin heads lying around, all have 26 mm studs, quite long enough even with 2 crush rings.
Don't know about Keihans though, and my finned clamps are flat-faced, no collet groove.
Original flange 2.5 mm thick, collets 18 mm long.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote simonnorthroad Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jul 2019 at 09:41
Thank you all for your advice. Yes the header-pipe is fully home inn the port. There is no old gasket in the port and Im using a new gasket in each side. I dont have a std header to compare the Keihan one too to, but it doesnt look excessively 'deep' .
Good advice on not 'mullering' the nuts up too tight. I was tempted...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jul 2019 at 10:22
Are the studs original or have they been replaced with shorter ones?
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simonnorthroad View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote simonnorthroad Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jul 2019 at 16:44
The studs arent original. They are stainless from Gutsibits (I think I got them from). I dont have originals to compare them to. They have equal amounts of thread at both ends
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kidneb Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jul 2019 at 17:36
Originally posted by simonnorthroad simonnorthroad wrote:

The studs arent original. They are stainless from Gutsibits (I think I got them from). I dont have originals to compare them to. They have equal amounts of thread at both ends

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