880 comp ratio?

[allanhanes]

Have a 2010 bmp 880? Want to know comp ratio. It has the 37cc domes I thinkin it high comp but can't figure it out. What is the 13-1 or 12-1 cc domes. We were riding low elevation and melted pto piston down. Thinkin we didn't have enough race fuel in it.
Thanks Jamie.

 

[byeatts]

Have a 2010 bmp 880? Want to know comp ratio. It has the 37cc domes I thinkin it high comp but can't figure it out. What is the 13-1 or 12-1 cc domes. We were riding low elevation and melted pto piston down. Thinkin we didn't have enough race fuel in it.
Thanks Jamie.

what jetting and elevation are you running?

 

[allanhanes]

Jetting

480 mains and was 3000 feet above sea level.

 

[byeatts]

480 mains and was 3000 feet above sea level.

you may be a size small on mains, But what do I know all my 880,s run at elevation, 490/500,s

 

[allanhanes]

880 bb

This motor previously has 1400 k on the 880 with 480 main jets and no issue. It was a warm day factory t stat in unit as well I am figuring the motor coolant was hot letting engine detonate which les to this failure. I was hoping I could find out the compression ratio we r running with the 37 cc domes if anyone knows and what cc the 13-1 and 12-1 bmp domes r.
Thanks Jamie.

 

[pfi572]

I will check for you Jamie as have one laying on the bench.