... because more better is how it is done overhere. 😏
Two sets of fresh valves and a bit of cleanup on the 700 heads kick it off.
Shame that those exhaust valves are bent...
Either way, get the new valves out and polish them to remove the coating.
After a quick lapping session, it's time to install the fresh valve(s)
... and then fill the exhaust port with petrol and see if anything seeps through.
And whilst I was at it, I cleaned up a small protrusion from the vacuum tube.
Quick shot of the old valves (bent - in case you didn't notice)
Headswap - other heads off, swap cams and adjusters and then time and install and reassemble the old girl: five and a half hours. I am starting to think that I might have done this a bit too often.
Some random stuff:
First the spark plug after 300km - looks like setting up the mixture with a wideband AFR meter has got its merrits.
Second: As these heads "failed" me the last time (it really was just a valve stem seal on one of them), I am very happy to report that not only did the heads NOT fail this time, the squish pad also seems to work rather well as indicated by the clean spots.
So why swap back? Well the 700 heads work a bit better at low rpm and the bike overall is not as hungry for revs. Also to harvest the full potential of the welded up heads, I would either have to angle the squish pad ever so slightly or run the old girl with an Ignitech box as there were some early warning signs for detonation. Just for the record: With the 700 heads and an optimised carb setup* some personal bests in the top speed department were recorded.
*VM38: #20, #180, one shim under needle, air screw one full turn - the shim equals to about half a notch on the needle. Next test will be raising the needle a full notch just to see whether this changes anything