650R - so that's why the valves seemed noisier....

6 replies to this topic
  • drzoomn

Posted July 15, 2006 - 11:48 AM


okay this can't be good...

Posted Image

so if you saw my previous thread, i had a problem where all of the sudden i had no more top end on the bike, seemed like a carb problem since all other operations were fine. so i took off the tank to check the main, when i was doing that i saw that the intake rocker arms had made an attempt to free themselves.

so i've yet to pull the head off, but so far i don't think any large bits of vavle cover made it in the motor. the shape of the hole looks like the pieces woulnd't easily fall in, and givin the force that busted it, it seems more likely it was ejected from the bike. also it had seemed noisier about 60 miles before the no top end thing happened.

the other odd thing i found, which i'm sure is the cause of the break out, is that the rocker arm has no tension on it, you can freely move it up and down, like way up. this doesn't seem normal. i haven't dealt with rocker arms since my old vws, and i don't remember them doing that.

anyway, &%$#@! is going on here?

  • Thumpmeister

Posted July 15, 2006 - 11:36 PM


Maybe your rockers shifted sideways? And your valve head snapped off, and shot up through?

I've seen snapped valves before, but nothing like this.

Are your rockers still in one piece? Maybe the part that rubs on the cam snapped off or something...

Good luck man...

  • Eddie Sisneros

Posted July 16, 2006 - 05:07 AM


looks like the lock nuts came loose and the adjusters backed out.

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  • drzoomn

Posted July 16, 2006 - 08:32 AM


hey eddie, i thought that at first, but with a finger test hey both seemed locked down just fine and i would think it weird for them to both get loose at the same time.

also is it normal for the rocker arm to be all loosy-goosy? i can easily pick up the arm and push it all the way up until it hits the top of the head cover.


  • Eddie Sisneros

Posted July 16, 2006 - 06:35 PM


no,not unless the cam lobes are gone.does it still run?you definately have some issues there.

  • motomonte

Posted July 16, 2006 - 07:11 PM


Holy :ride: man,I haven't noticed how many posts you have.30k coming up... :thumbsup:

  • drzoomn

Posted July 16, 2006 - 07:43 PM


no,not unless the cam lobes are gone.does it still run?you definately have some issues there.

ok, yeah i did not think that was normal, that just seemed way too messed up.

the bike still runs, but it has no top end. it got a little noisy at first, wasn't sure if it was me just noticing how clackity it was or the bike. so i topped of the oil and the next ride out it suddenly lost full power. since i was almost out of gas i thought that was it, but after hitting reserve and filing up it stayed that way. from about 0 to 1/2 throttle it seemed okay, but after that it was gutless and at WOT it would not redline. but it started and idled fine.

i was too busy with the house to crack it open further. i thought it was a 20 min carb clean job when i found that mess. next weekend i'm off for motoGP so i'm not sure when i'll get to it. i'll post more pics when i crack it open. after the kibblewhite issue, that will put two headless thumpers in my workshop! :thumbsup:

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