While the head is off.....

lazyeye6 · May 24, 2020

quite the bump!

gortnipper · May 24, 2020

Just make sure you check you dont bump your valves with the piston.

Maybe somebody skimmed the head and barrels a bit much?

Chris Zet · May 25, 2020

When you have got the barrels off then i highly recommend to get you the barrel stud and 12 point nut set from cnw...... 12point nuts are always the better choice....

SteveA · May 25, 2020

gortnipper said:
Just make sure you check you dont bump your valves with the piston.

Maybe somebody skimmed the head and barrels a bit much?

Certainly worth a check before you just take that much clearance away without testing, may have been done to cope with low octane fuels in your area or an overskimmed head/barrel face....

concours · May 25, 2020

I used the .021” heaaket to liven up my 850, 36,000 miles, no regrets

Custom Thickness Copper Head Gasket (add pliobond sealant - not included)

Available in various thicknesses to alter compression. 3/32″ and 1/8″ gaskets are available on special order at double the cost (contact us). Crushable thin .005″ copper wire is provided for looping…

jsmotorsport.com

MarcoNC850 · May 25, 2020

SteveA said:
Certainly worth a check before you just take that much clearance away without testing, may have been done to cope with low octane fuels in your area or an overskimmed head/barrel face....

I will definitely look at the clearance at TDC and have Jim look at the Carbon Ring on top barrel, I did not measure but looked like plenty of clearance.
Does anyone know what is the gap I want to see there?

SteveA · May 25, 2020

MarcoNC850 said:
I will definitely look at the clearance at TDC and have Jim look at the Carbon Ring on top barrel, I did not measure but looked like plenty of clearance.
Does anyone know what is the gap I want to see there?

Jim will give you a good figure for the combination of parts you are using, but nothing less than 0.050"