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Discussion Starter #1
i'm in the middle of my first honda twin resurrection. i'll try to post relevant questions in relevant forum section but please forgive if i overlap a bit.

some back story: low compression-adding oil helped a bit. tore down top end. bore within spec going to re ring. both exhaust valves bent. the only thing in my experience that bends valves is hitting a piston. the only way that can happen in my experience is mistimed cam/crank due to tensioner or chain failure or over rev. i'm guessing it was over revved before i found it.

the rubber tensioner doesn't look great but i'm replacing it and the timing chain. is there a happy medium between the suspect rubber wheels of which i'm now a little gun shy and the KA performance slippers that cost a pretty penny? anyone magic up a steel one?
 

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All the tensioner parts except for the "pushrod" stuff are still available from Honda.
Sounds like you're doing this right, so...might as well do it right.
The only one that's pricey is the roller on the lever. The big roller in the middle and the slipper aren't that expensive.

See if you can find some new valves and let your machine shop do the valves.
With good compression you'll be a Happy Boy, everything else will fall into place.

Photos please.......
 

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I don't know about 350s specifically, but over-revving tends to result in broken piston rings (no idea why), if you're looking for clues as to how the valves got bent.
 

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KERRY said:
I don't know about 350s specifically, but over-revving tends to result in broken piston rings (no idea why), if you're looking for clues as to how the valves got bent.
What specific event brings you to this conclusion Kerry???


GB :mrgreen:
 

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I'm with GB on this one... What do broken rings (which he did NOT mention) have to do with bent valves??????
 

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Discussion Starter #6
i was planning on just lapping the new valves in. is a valve job necessary on these bikes when replacing valves?

i was expecting to see some sort of ring problem on my tear down but they were free, undamaged, and no sign of blow by. the pistons themselves are not scored or damaged. they obviously took a hit but don't show any valve kisses.

i will post pics as requested once i liberate my camera. i do wish i had some before photos. not much to look at now but i can show the questionable components.

generally the rubber tensioner is good to go and if i replace it i shouldn't worry about it failing again? the old one is hard as plastic and slightly chipped along the wheels but i suppose it is almost 40 years old. so i shouldn't worry too much about getting a slipper for general road use?

thanks,
scott
 
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