Slabbie 7/11 thunderbike racer

[Spazpecker]

Oh no! That sucks. 

Stick the other B12 in her and turbo this one? 

[vizman]

Hopefully nothing too serious dunc, and then back to carving up fresh meat.

[KATANAMANGLER]

Hope it's not too serious Dunc. 

[R1guy]

It’s @dupersunc and this is OSS.

He’ll just have to rebuild the motor bigger, better and with more power.

[dupersunc]

Post mortem.

Source of the smoke, heads bolts weren't very tight. Ho hum. Head needs a very light skim to clean it up.

There's more.

Hmmm

Well we cocked that up.

Stock exhaust cam and timing. Need to figure out what gone wrong here. Not enough valve clearance, or am I revving it too hard.

[Markz9]

21 hours ago, dupersunc said:

Post mortem.

Source of the smoke, heads bolts weren't very tight. Ho hum. Head needs a very light skim to clean it up.

There's more.

Hmmm

Well we cocked that up.

Stock exhaust cam and timing. Need to figure out what gone wrong here. Not enough valve clearance, or am I revving it too hard.

Have you checked yet to see if the head or barrels have been previously skimmed 

[dupersunc]

3 hours ago, Markz9 said:

Have you checked yet to see if the head or barrels have been previously skimmed 

No. The motor was originally built as a side car motor reputedly by Mistral racing. Who ever did it originally knew what they were doing as there is some nice work been done. I gave it a quick once over, and kept the came timing it was originally built with.

Need to do some carefully dummy builds to check cam timing and piston to valve clearance. I suspect it's just been over revved.

Some 750 valve springs may be in order, as well as more regular checks on head torque and valve clearances.

[Kamikaze]

ahhh not good to hear Dunc, hope u get it sorted soon mate. Always keen to hear ur racing reports and R+D