I'm looking for an 8 bolt 1936/7 M20 cylinder head. Fin condition isn't important..in fact one with damaged fins would be better for my purposes..Due to weight the UK or close would be ideal...anything out there?...Ian

email (option): ian@wright52.plus.com

Can't help with a head Ian but as I read this request I had just been viewing a web page with some interesting use of BSA parts Inc M20 heads. Also some fairly wild specials..

http://www.diagnosis2012.co.uk/vtwininnovators2.html

i was thinking whether a yamaha xt 500 engine and g/box would got in a m20 or b31 frame

email (option): roger.beck@node6.com

This would fit..

The problem is stopping it.

email (option): noam10@gmail.com

If you are changing the bike that much fit a BSA 8 inch brake as I have on my M33 with girders.

suzuki LS650 is not very much faster than M20

email (option): kalle.tikas@gmail.com

Hi Fred..That's an interesting site...I spent a couple of hours marvelling at peoples ingenuity and skills...and wondering what drugs some of them are on.. ....Ian

email (option): ian@wright52.plus.com

Same here, I spent ages checking all the links looking for more info on the 960cc B31 single that's mentioned but no luck.
The Aussies & Kiwi's seem to have have a genetic inbuilt resourcefulness that was needed in the early days of survival in those places I think. The old brass tap on one bike is the kind of thing I like seeing :-D

Hi Fred..Yes, Plenty of food for thought and interesting features if you like 'specials' (as I do).
Even with an M21 crank at 112mm stroke he would have needed a bore size of approx. 105mm to get 960cc..My own B33 is on the limit physically at over 700cc, with regard to the head bolt positions particularly..I think he must have used 'through studs' to make room for the barrel and have manufactured a barrel as well..there's no way to get that bore size and still have a barrel with the standard B33 barrel...which is bigger in diameter at the 'narrow part' than the B31 type.
All interesting stuff though and a feast of original thinking...Ian

email (option): ian@wright52.plus.com

Yes, I'd like to get more info on the single.
I am intrigued by the "leather covered" wheel spokes on the 3000cc Big Ned ... Wonder if they were inspired by 1920's Bentley leaf spring covers.
I'm surprised the G14 bottom end is up to the job on that first machine featured, I'm fairly sure the conrods sit "side by side" on those rather than one forked rod, like the Y13 & Harley's. But if it works that's good enough.

Edit... They are forked on G14, I just checked, its just the "J" type V Twin that has side by side big ends.

I had a 1936 G14 and wouldn't think the bottom could stand too much load...The big end isn't very heavy, it is pretty short on main bearings and the large crankcases have no strengthening ribs on the face or round the bearing housings..It's easy to forget..or just ignore..how much engines were developed and strengthened through the 30's. A J.A.P DTZ motor would be more up to the task I reckon. When I mentioned to someone once the G14 had a 'total loss' oil system he commented..'Oh yes, I used to have a Triumph like that'.. ...Ian

email (option): ian@wright52.plus.com