Hole in Cylinder Head on F2

[Warthog1959]

My apologies if I have not done a formal introduction, I joined over 2 years ago and cannot seem to find my old posts if any.

Big problem

I built an F2 cafe racer in 2009 and kitted out the engine with an 836 kit and new valves, titanium valves guides, chain, engine studs, cam etc. It also now has 29mm smooth bore carbs. I have been observing a slight oil seepage on the fins. This very small oil leak from the fins recently started to grow to the point of running down and off the frame, only after a ride, but not whilst just sitting there like an old brit bike.

I have had the right hand exhaust off and between the first two R/H/S exhaust ports I can see what appears to be a shiney shaft, which I can only assume is an engine stud. I surmise from this I have melted a hole in my cylinder head. Not sure how, although with all the tuning and upgrades the performance increased immensely. I'm not sure where maximum Red line would be on this config, but I may have gone past it a couple of times. All that said and done I would not expect to melt a hole in the cylinder head. Can anybody out there clarify, what may have caused this. Also has anyone got an F2 cylinder head for sale?

[Bryanj]

I doubt you have melted a hole as to get that hot it would have siezed first, common problems in order are

(1) Rubber seals under the cam bearings shrink and leak

(2) studs that hold down the cam towers strip the threads and leak down the threads (Keensert rather than helicoil for repair) with sealant on both insert thread and stud

(3) if its an F2 the domed cylinder head nuts on the wrong studs and/or the proper sealing washer not used or need replacement.

F2 heads are a bit rare now due to their propensity for wearing out valve guides in 15,000 miles---especially exhaust