There was a big bump on the short turn radius coming out of the valve seat.teazer said:Does the piston have a flat squish band/quench area? If yes, then that will work. My personal preference is a 14-15 degree squish band angle on the head an one degree less on the piston. That will eat into the valve seats and will eat some of the top piston ring land, so it's all a compromise - I may have read that somewhere.
And you may have to pocket the valves slightly and/or deepen the pockets in the piston crown - so it goes on.
BTW there is more metal that could come out of that port roof but try not to shorten the guide any more than it is. The roof is where the action is. Less going on with the sort turn radius (floor).
Rings are .87mmteazer said:Not a lot of meat in that top land to machine it much more. How thick are the rings?
When you say Ti tappets do you mean the valve adjusting screws? Worth a go, but I suspect that they will mushroom and gall as the tip rubs back and forth on the valve tip. One trick I have used in the past is to drill them from the screw end down through the soft core and have them broached to take an allen key. Another one is to use Ti or Al nuts. The problem I found with Al nuts is that they tend to loosen and had to be checked after each race. Rocker arms can be lightened quite a bit too.
If the Ti screws work, I'll have to get a set. What's available for pit bikes from Kitaco or others?
If you go with Ti valves, give them extra clearance and hardened steel caps and leave out any valve seals. The sideways motion tends to cause them to gall.
Wait till you see the rest of the bike Fuller likes his peasstroker crazy said:Nice bolts!