2010 Bent Exhaust Valve @140 Hours


9 replies to this topic
  • luckyguy19

Posted September 02, 2012 - 09:08 AM

#1

This is about the worst time for this to happen. We are going camping in a week and I hope it can be fixed by then. The right side exhaust valve is bent quite bad. I was riding and the bike just died. Looks like it got stuck open and hit the piston. I hope its just a valve,guide and keepers and labor to install the valve in the head. I can get it done in time if that's all it is. Anyone know the labor time for just replacing one valve?

I should mention I checked timing before I took it apart and it was correct.

Edited by luckyguy19, September 02, 2012 - 09:17 AM.


  • Just_a_trail_rider

Posted September 02, 2012 - 10:06 AM

#2

Labor time for replacing a bent valve will be minimal. I know on my 05 yamaha, I had both exhaust valves replaced, all new springs, seals and the seats cut for less than $400. But you gotta take the head off first and get it to a shop. If they have the parts and the time, it will take a couple of days.

  • luckyguy19

Posted September 02, 2012 - 01:36 PM

#3

Well I got lucky considering. Buddy of mine had a valve spring compressor. Got it all apart. Looks like the tip of the valve failed, and let the valve drop into the cylinder. Valve hit the piston and bent. Took the other exhaust valve out and its great. Tried the other valve in the valve guide of the damaged one and it was perfect. Valve seat is also untouched. So its a valve, keepers, seal and bucket. I don't have to worry about any labor or machining. Should be able to get it back together Weds night. I already had a piston and upper gasket kit because I was gonna change the piston soon.

  • Joe_Jet

Posted September 02, 2012 - 05:01 PM

#4

Sounds like a temporary fix. Im sure youll lose the other exhaust valve real soon. At least replace both exh valves with high quality ones. Still kinda hokey if you dont recut and seat. You should be stoked getting 100 hours out of the bike!

  • luckyguy19

Posted September 03, 2012 - 09:54 AM

#5

Yeah, I think I'm going to count on replacing all the valves in the head including having all the seats cut after our camping trip.

I'm replacing all the parts with OEM parts.

Edited by luckyguy19, September 03, 2012 - 09:54 AM.


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  • Family Man

Posted September 03, 2012 - 12:29 PM

#6

I had MXtime do the head on my 07 and its came back shimmed with ports polished with new valves and springs for alittle over 500.

  • luckyguy19

Posted September 04, 2012 - 08:18 AM

#7

The dealer had the parts in stock!!! So since I don't have to overnight parts, I'm going to replace both exhaust valves and they are going to cut the seats for me. Bike should be 100% now, and the head will be done and ready today.

  • rickallen124

Posted September 07, 2012 - 04:32 PM

#8

Well I got lucky considering. Buddy of mine had a valve spring compressor. Got it all apart. Looks like the tip of the valve failed, and let the valve drop into the cylinder. Valve hit the piston and bent. Took the other exhaust valve out and its great. Tried the other valve in the valve guide of the damaged one and it was perfect. Valve seat is also untouched. So its a valve, keepers, seal and bucket. I don't have to worry about any labor or machining. Should be able to get it back together Weds night. I already had a piston and upper gasket kit because I was gonna change the piston soon.

I heard of this happening on a low hour 2010 2 years ago, tip just broke of and the valve dropped. Must of had a bad batch.

  • luckyguy19

Posted September 09, 2012 - 06:51 PM

#9

That actually makes me feel better. I keep thinking there's something else that caused the failure. But I'm very anal about oil and filter changes, as well as valve adjustments. I've never had this sort of problem with any other bike I've owned. I ran the bike up in the mountains each of the last three days and it performed great. Hopefully this problem is behind me now.

  • dirtriderbc

Posted October 01, 2012 - 05:52 PM

#10

My '10 with about 130 hours stalled out on the trail this weekend. Put 'er back in neutral, went to kick, and it wouldn't budge. Rocked the thing in gear a bit, back to neutral, then was able to kick it over. When it fired, it made a horrific noise, like piston/valve contact.. Hope I'm not in the same boat as you guys. I, too am fussy about oil changes, checking things over, etc.. Just got done putting a new piston, rings, timing chain & tensioner, gaskets, etc. after the same thing happened at the dunes back in May. Thought this bike was supposed to be so reliable. Any suggestions for aftermarket valves, I'm not sure if these Yamaha titanium valves are any good...





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