107 piston options

[Raleigh111]

I have been away for awhile on other ventures but before i left i collected some nice ported heads and cr 575 cam. Problem is the heads are 83 cc and i do not want to run a real fat head gasket. Looking for suggestions on 3.938 cast pistons that are at least -2.0cc or more. I will squish it to 10.6 but not wanting to go more then that. Would prefer 10.3-5 range. I would also consider 110 kit but would need even more -cc then 2.0 BTW in Sturgis now boys, been riding since 8-1 racking up miles having fun.

[Don D]

Built the same combination at 113" 10.3 with my Street Pro heads and it made 117/127. Not a barn burner but hits 110 TQ at 2000 rpm.
I have a set of KB pistons in stock that are -1.6cc. Consider this close enough and move on. These pistons have an anodized coated top and are line2line coated skirts

[Raleigh111]

Built the same combination at 113" 10.3 with my Street Pro heads and it made 117/127. Not a barn burner but hits 110 TQ at 2000 rpm.
I have a set of KB pistons in stock that are -1.6cc. Consider this close enough and move on. These pistons have an anodized coated top and are line2line coated skirts

So if i am figuring correct lets see.
.030 head gasket 3.910,, leave pistons down hole which are usually .004 .006 range 83cc heads -1.6 pistons would put me in the 10.54 range and .040 head gasket 10.34 range. Not a big fan of .040 head gasket but?? Maybe .035? anyone make .035?  If i get them zero decked and run .035 puts me 10.54

[Don D]

HG= 3.96" bore
Cometic will make you a custom but IMHO and experience I think it is a waste of effort, use the .040 off the shelf, splitting hairs.

[jsachs1]

Cometic has .036" head gaskets for most bores.
John

[kd]

 

[Don D]

Part number is C10083-036

[dsvracer]

How about just making the combustion chamber a little bigger, take your dremel and just remove a little metal and you will get the compression you are looking for.  dsv

[BVHOG]

The pistons Don has are the best out there IMHO,  that 575 can easily run with 83 cc  and a 40 gasket or you can just as easily relieve combustion chambers like previously mentioned.

[Hillside Motorcycle]

I have been away for awhile on other ventures but before i left i collected some nice ported heads and cr 575 cam. Problem is the heads are 83 cc and i do not want to run a real fat head gasket. Looking for suggestions on 3.938 cast pistons that are at least -2.0cc or more. I will squish it to 10.6 but not wanting to go more then that. Would prefer 10.3-5 range. I would also consider 110 kit but would need even more -cc then 2.0 BTW in Sturgis now boys, been riding since 8-1 racking up miles having fun.

Our Wiseco/J&E forgings, #HMM 00107, in flat top are -2.3cc.
Armor coated full skirts, and 3mm oil rings.

[BVHOG]

Wiseco has definitely stepped up it's game the last couple years with coatings and ring pack but I'll take the UEM KB first EVERY time.