This Forum is now CLOSED use the link to get more details viewtopic.php?f=3&t=13924#p102587
By Rodders
The head gasket(s) on my 1955 500 Twin have blown, or one of them has, after about 3,000 miles. It's actually broken at the thin part between the two cyclinders. Is this the usual weak spot, or is there anything I should be doing when I replace them?
Many thanks,
By Vince2
Hi, they tend to go between inside head studs. Are you using solid copper or copper/asbestos gaskets? Vince
By Rodders
Hi Vince, thanks for the reply. I was using copper but our hosts now sell composite, which I'm about to fit. See how this works out. Regards
By Vince2
Hi, I take it that we're talking of small bore twin . Check that the barrel spigot fits into the head (remove any carbon) and measure the gap without gasket. Vince
By Meteorstorm
Usually you have to give these heads a swipe over some wet or dry,on a flat surface,which will immediately show hi spots which will normally be where the head bolts distort the cyl head through over tightening,this can lead to problems yours experienced, good idea to correct this before putting those heads back on.

Shop for accessories at Hitchcocks Motorcycles