Getting a bit stressed. I have now bent two inlet valve push rods and bent two inlet valves that makes four. It happens after a 120 Km an hour cruise on the highway. Just after i close the throttle and the bike is decelerating for the stop. The inlet valve hits the exhaust valve. I was advised to change the valve guides. The local guy advised me to fit Cast Iron guides. As i understand it if you have cast iron guides you do not fit valve stem seals. He keeps on putting on valve stem seals. Is that correct or could that be part of te problem. It is like the exhaust valve gets stuck momentory. Could the cam be a problem? I have not done 150 Km since i bought it without stripping the engine down. Help would be apreciated. Only one guy working on shovels in Cape Town

 

What custom motor work has been done? For a stock motor, I've seen bent valves and pushrods caused by the improper adjustment of the hydraulic lifters. They must be allowed to bleed down after adjustment before turning the motor to adjust the next one. This is critical. If the cam has too much lift it could cause a problem. I've also seen valve seats come loose and bend the valves.

 

Unfortunatly i do not know what was done the previous owner passed away. I think he is giving me all the problems. I have a gauge i got from J&P that i adjust the hydraulic lifters with. What worries me it is fine riding arround town. This only happens after a highway ride and when i the slow down. Do you know the clearances for iron guides perhaps

 

seal dont have anything to do with it,if a valve stuck,it would stay stuck.you may have a cam with alot of TDC lift and heads are not set up right.replace bent valves before doing alot of riding.the valves will try to straighten out every time they get back on the seat and eventully break the heads off (79-80 shovels where notorius for this anyway)any good shop should be able to figure out prob by checking heads
kirby