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Exhaust studs dimensions

759 Views 1 Reply 2 Participants Last post by  NorthCust
I want to install a BW exhaust but need to remove the old studs as they have seized up. The BW exhaust shows them using bolts instead of studs. Was wondering what is the thread in the engine head and how far do they go into the engine block.
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iirc they're m8 x 1.25. I had to replace both studs in the head of the engine I have in now but they were just studs from a big box of assorted exhaust studs rather than ones I bought specifically.

Removing broken-off studs is likely to be very difficult or impossible with the engine in the bike. I had a nightmare with mine and that was with the cylinder head on a workbench. Assuming your studs are not broken - proceed very cautiously and with a lot of WD40 (pref liberally soaked the night before).

Imho studs > bolts for the exhaust for the simple reason that you can use non-seizing nuts (e.g. copper or brass exhaust nuts) on a steel stud which will not corrode in place or snap the stud on removal..thus avoiding the situation you find yourself in now.
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