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#2 Exhaust fouling frame

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Lobo:
Having an issue with #2 exhaust butting up against the frame in the side-stand area on the ‘750 K2. Everything OEM; and despite loosening all fasteners, and thence retightening with the pipe held clear… it simply resumed its ‘comfort zone’. Which is not mine!

Comments / tips please?

Laverda Dave:
I had a similar issue with the DSS repro full 400/4 system. No.1 down pipe kept pushing hard up against the sump no matter what I tried. I did the same as you, undoing all the mounting points including the exhaust collars at the head in an attempt to ‘persuade’ it into position. Every time ‘I got there’ doing up all the fixings in sequence to a correct tightness and a bit at a time the final tightening would make it spring back again! Eventually I took everything off apart from No.1 header and used brute force to very slightly tweak the line of the pipe in various places (with my hands and using my knee to support the pipe) whilst keeping it fixed tightly in the cylinder head via the exhaust clamp. It worked with no visible alteration to the line of the pipe and it went into the collector box without any issues but I must have spent 3-4 frustrating hours doing it. Ideally I should have made a template with a coat hanger, filled the pipe with sand and taken it over to the vice to tweak it, problem with that was a very large wodden mallet was close by and I know the frustration would have got the better of me :o. At least keeping it clamped to the bike allowed me to trial fit the rest of the system in stages and get it right.

I’m surprised you are having trouble with an OEM part although as has been said many times before, OEM is slightly different from ‘Original’ or ‘NOS’. It might be OEM but is the OEM using the same original jigs to make them? DSS and CMS state their systems are a straight fit but I can argue otherwise especially for the 400/4 >:(

Keep tweaking it and you will get there unless it is really bad in which case send it back to the OEM. Enough of these sets have been sold so it will be interesting to see if anyone else has had the same issue and how they cured it.

Johnny4428:
I have a problem with my No2 exhaust pipe up against the oil filter housing. Bloody annoying having to remove exhaust to change oil and filter. 😡

Oddjob:
Most of these problems end up being bent brackets, if it's not the fault of the exhaust itself. Try removing the hanging bracket and test fitting it just using the head clamp, see if you can hold the bracket against the frame and work out which way bending it would work. The DS hanging brackets for the 500 system are well known for this.

Lobo:
Thanks gents - my lazy error Dave, indeed all is original / NOS. I reckon it’ll be Ken’s suggestion… it was my next avenue but always hopeful of something easier! Whilst I’m here, given engine movement, what kind of ultimate gap am I looking for… 5mm?
Ta.

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