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[Sticksy]

Would any-one identify a timing side crankcase for me please?
500 Bighead Bullet 1961 with an engine that is a bit of a mystery.
Unmatched crankcases - drive side looks original but timing side has no oil sealing bush-just 2 grooves machined in the bore, and no machined counterbore for a rubber seal either. Any ideas please?

Also it has a bent mainshaft, chipped and scratched alloy connecting rod and has had a high compression piston fitted taking the cr from 7.25 to - 6.3!! fitted to a glazed cylinder with .010 clearance.Excellent stuff.

[Mark M]

Sticksy, it's Mark here. Which bore in the timing side case are you referring to, the magneto/distributor one or the crankshaft one? Late Bullets didn't have a seal on the timing side crankshaft, early ones had a scrolled bronze bush. The neoprene seal wasn't used by Redditch at all, the Indians introduced it some time in the 90s I think? Which mainshaft is bent? Timing or drive? Depending on which, I might be able to help. Just got my BH crank from T & L !

REgards, Mark

[Sticksy]

Hello Mark,
Thanks for your reply.
The bore is where the bush would be fitted to seal the timing cover from draining, mine just has the bare alloy a close fit around the mainshaft. Thought they all had a bush so was wondering what case halve it is.
The threaded end of the drive mainshaft has been bent so that the rotor has cut into the stator!

Are the people that did your crankshaft local-ish? Are you happy with it?

I hope to get a new mainshaft, steel connecting rod and forged 6.5 Accralite piston, even though i don't like forgeries! Thinking of a plain big end as it used to have. Andy.

[Chris Tindal]

Sticky, as Mark says the late Bullets didn't have the bronze bush, just bare alloy with the two oil way grooves. If your engine is 61 this is what it will have been like. Have you checked out the numbers on each crankcase half behind the front engine plates? These will confirm if they are matching or not. Apparently it doesn't actually matter as the crankcase halves were never machined together anyway. Mine doesn't have the bush and its only wetsumped once in two years so it's not a problem. When I first got my BH bullet it was a total and utter abomination put together by a ham fisted Neanderthal. Don't loose heart, they are lovely machines once they are sorted. I had my crank rebuild by alpha bearings with a steel rod and roller although I'd be happy with the floating bush. They balanced it to the forged piston and it's really smooth with very little vibration at 60mph.

[Sticksy]

Thank you very much Chris,
You've put my mind at rest - i wondered what crankcase half i had, but now i know it is genuine that's great. They are unmatched - one of the numbers has been overstamped but no worries now i know they were machined separately.
I rode it twice before taking it apart and it was lovely to ride.

Thank you Chris and Mark, very kind and the encouragement was most welcome.
Safe riding.