1919 AJS 750cc V Twin Restoration

[olderdan]

Thanks Tony
I totally agree this is a bad design.
You are correct in that the main shafts have protruded into the flywheels a little further (it is a 16 degree inc taper), I had to shorten the small taper end and the threads to compensate. I actually ground the nut clamping faces and faced the nuts from a tight fitting screw cut mandrel to avoid any bias to the crankpin. This is an old chuffer of an engine and only rated at 4HP which is why it survived the abuse. I havent got to the timing gears yet and the cases have had a fair bit if welding so more trouble ahead.

[olderdan]

My original HP figure was a typo, the official one is 6HP.

If the crank assy is a flimsy affair how about the barrels and heads held down by a stirrup with two bolts each and a bicycle type rim brake on the front.

[tonyfoale]

My original HP figure was a typo, the official one is 6HP.

If the crank assy is a flimsy affair how about the barrels and heads held down by a stirrup with two bolts each and a bicycle type rim brake on the front.

Be careful with that much power.

I think it was Panther which had extra bosses cast under the main bearings with a groove in. Then large U bolts went under the bosses and fitted in the grooves. The legs of the U bolts went up into the head in a normal fashion. It sounds crude and it was, but it meant that the combustion forces were taken all the way down to under the main bearings, so you were not trying to tear the crankcase apart like you do with most engines. So it was not quite the crazy idea that it sounds.