Z1OwnersClub GB

Blackseven wrote:Why would it be a problem to use stainless on the camshaft bearing caps?

You might (maybe) if yr very unlucky find that the stainless behaves differently under the very high frequency altering load from the cams and stretches or snaps. I’m not a metallurgist so I’m no expert but there doesn’t seem to be any point in deviating from oem bolts there. On later gpz motors the cam bolts changed I think so that they had an unusually thin shank, so kawsaki presumably felt the need to tune the way these bolts behave under tension.

Only other thing against stainless is that I’ve found that the hex socket in cap heads tends to relax quite quickly with repeated use, so there’s a higher risk of them rounding off.

Pigford wrote:

Blackseven wrote:Why would it be a problem to use stainless on the camshaft bearing caps?

Think he means there's no real advantage?

Well, that for sure and as also noted above, the small possibility that SSteel bolts may not have the same tensile / work ratings as the original cam cap steel bolts. The high frequency shock loads may or may not (probably not) be an issue for the bolts, possibly more importantly, seems that stainless also expands more when it gets hot so if there is an issue it's likely to be heat related. But overall it's a case of those bolts in particular are well protected and unlikely to need replacing, so if they aint broke, don't fix them. According to the parts list, the bolts for the caps & the cover are the same item so there's probably nothing special about them tensile wise.

cancunia wrote:

Pigford wrote:

Blackseven wrote:Why would it be a problem to use stainless on the camshaft bearing caps?

Think he means there's no real advantage?

Well, that for sure and as also noted above, the small possibility that SSteel bolts may not have the same tensile / work ratings as the original cam cap steel bolts. The high frequency shock loads may or may not (probably not) be an issue for the bolts, possibly more importantly, seems that stainless also expands more when it gets hot so if there is an issue it's likely to be heat related. But overall it's a case of those bolts in particular are well protected and unlikely to need replacing, so if they aint broke, don't fix them. According to the parts list, the bolts for the caps & the cover are the same item so there's probably nothing special about them tensile wise.

I kept the camshaft bolts original - just changed the cover bolts for S/S

bulldogbobby wrote:

cancunia wrote:

Pigford wrote:

Blackseven wrote:Why would it be a problem to use stainless on the camshaft bearing caps?

Think he means there's no real advantage?

Well, that for sure and as also noted above, the small possibility that SSteel bolts may not have the same tensile / work ratings as the original cam cap steel bolts. The high frequency shock loads may or may not (probably not) be an issue for the bolts, possibly more importantly, seems that stainless also expands more when it gets hot so if there is an issue it's likely to be heat related. But overall it's a case of those bolts in particular are well protected and unlikely to need replacing, so if they aint broke, don't fix them. According to the parts list, the bolts for the caps & the cover are the same item so there's probably nothing special about them tensile wise.

I kept the camshaft bolts original - just changed the cover bolts for S/S

Threads of both cam cap and cam cover bolts are prone to stretch. You need to check pitch is correct before refitting.

ADRIAN H wrote:

bulldogbobby wrote:

cancunia wrote:

Pigford wrote:

Blackseven wrote:Why would it be a problem to use stainless on the camshaft bearing caps?

Think he means there's no real advantage?

Well, that for sure and as also noted above, the small possibility that SSteel bolts may not have the same tensile / work ratings as the original cam cap steel bolts. The high frequency shock loads may or may not (probably not) be an issue for the bolts, possibly more importantly, seems that stainless also expands more when it gets hot so if there is an issue it's likely to be heat related. But overall it's a case of those bolts in particular are well protected and unlikely to need replacing, so if they aint broke, don't fix them. According to the parts list, the bolts for the caps & the cover are the same item so there's probably nothing special about them tensile wise.

I kept the camshaft bolts original - just changed the cover bolts for S/S

Threads of both cam cap and cam cover bolts are prone to stretch. You need to check pitch is correct before refitting.

Thanks mate