BMW S1000RR Forum banner

1 - 5 of 5 Posts

·
Vendor
Joined
·
2,647 Posts
Has anyone here put any head gasket 0.870 in a hp4?
Here is what I can tell you about the stock head gasket. it is used in every 999cc engine that came in

K42 (HP4)   (09/2011 — 07/2014)
K46 (S 1000 RR)   (09/2008 — 11/2018)
K47 (S 1000 R)   (02/2013 — 12/2018)
K49 (S 1000 XR)   (05/2014 — 12/2018)

So, that head gasket is 1,12mm for everyone except China and they get a thinner gasket at 1,02mm. I have tried to convert this 1,12mm to inches but I dont understand how the Germans write this metric expression of thickness.

What 0.870in works out to 22.098 Millimeters and this number does not make sense to the 1,12mm in the parts catalog.

I am now curious how China would get a thinner head gasket and raise the compression on the China made S1000RR's. Their octane is no better than the USA octane levels.
 

·
Registered
Joined
·
81 Posts
All measurements metric
1.12 mm , two marker holes to indicate thickness
1.02 mm , one marker hole
0.87 mm , no holes
Never did the math on compression ratio change or valve clearance by running that gasket.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #4
All measurements metric
1.12 mm , two marker holes to indicate thickness
1.02 mm , one marker hole
0.87 mm , no holes
Never did the math on compression ratio change or valve clearance by running that gasket.
Here is what I can tell you about the stock head gasket. it is used in every 999cc engine that came in

K42 (HP4)   (09/2011 — 07/2014)
K46 (S 1000 RR)   (09/2008 — 11/2018)
K47 (S 1000 R)   (02/2013 — 12/2018)
K49 (S 1000 XR)   (05/2014 — 12/2018)

So, that head gasket is 1,12mm for everyone except China and they get a thinner gasket at 1,02mm. I have tried to convert this 1,12mm to inches but I dont understand how the Germans write this metric expression of thickness.

What 0.870in works out to 22.098 Millimeters and this number does not make sense to the 1,12mm in the parts catalog.

I am now curious how China would get a thinner head gasket and raise the compression on the China made S1000RR's. Their octane is no better than the USA octane levels.
the question is whether it will work well with the head gasket 0.870
 

·
Administrator
Joined
·
6,702 Posts
The difference is 0.25 mm or 0.01 inches - that seems like a big difference to me, compression ratio more so than valve clearance. The squish area is only 0.040 inches to start with I think? Maybe someone that's measured this all out can chime in, I've only used the stock thickness. Sorry Valter no definite answer from me. Maybe Alpha can tell you?
 
1 - 5 of 5 Posts
Top