Sunday 17 July 2011

Back in business.

The piston got torched previosly, I had trouble finding a replacement as it had a long rod high comp one in there, any b series owners may know that most stuff like that is for the short rod later versions. I managed to track down a +40 piston at a sane price from Petes classic bike parts in the Netherlands. The previous piston was a strange one as it was an actual BSA piston (not Hepolite or etc), and since getting this new one I now realise it was like 8:1 cr, wheras the one I got to replace it is 8.5:1. Hope thats not going to cause problems!.This one is a MC cast piston. It has a skirt seperation slot which the other one didn't so hopefully that will make it less likely to nip up.
I spent ages trying to fit the final circlip in, then I could not get it to seat, after ages I realised I was putting it in the side that already had a circlip!
I hate doing the timing, 7/16" btdc. It took ages to do, only to realise I made the mistake of setting it to 7/16" after tdc! 2'nd error of the day. Set it to the reccomended 7/16"btc fully advanced, but seems to me ike there's a lot of variables to simply set the pionts to .002 @ 7/16" btdc. What about mag pinion play and stuff.
Stagger the ring gaps, none on the thrust side bla bla.