Topic: Pistons

[Wezzo]

Afternoon. I’m new to the CB759 engine so forgive me as I’m sure this has all been covered before. Trouble is, this forum is now so full of information it’s difficult to find anyth8ng quickly, so here goes.

I’m looking to put together an engine with a few tweaks, cam, pistons, etc. to give an ‘fast street’ characteristic and I have a few things I’d like to check with you guys.

1) Pistons. What’s the view on the following. I appreciate that the vale clearance will need checking

      a) CB750 F2 domed pistons with an F head. What kind of compression would this give over the flat top pistons?

       b) CB77 +1mm. These have high compression tops with recesses for the valves. Any idea what compression ratio would be returned?

Considering a) and b) would an 810cc be better than a high compresssion std bore.

Cams. - I’m thinking perhaps a Kenny Harman D, Webcam 41, Yoshi Road and Track

Thanks in anticipation. All the best. Wezzo



       

[Don R]

 F2 pistons on an f2 head equals stock F compression. I don't think they work with an F0 or 1 head.
 An 812 is a good combo, I'm not sure about compression with those pistons. Once upon a time, cycleX advertised an 812 kit but they don't have everything their web site shows in stock.
  A few of us have built the ebay cruisin image 836 kit motors with good results. There is a long thread about those somewhere in this site.

[Stev-o]

Seems 836cc is a much more common size to go to, why don't you consider that if you are boring?

I did that on my K4 and used Wiseco pistons along with a K/H D grind cam, highly recommend.