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Bent valves???

Old 06-05-2012, 04:11 PM
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Bent valves???

My stock cct failed(spring) on the front cylinder while i was riding (low speed 3rd
gear 3500). I threw the bike to neutral as it clunked to a stop and i pulled over. I put it in a truck and took it home. tried to start it to diagnose problem (this was before i learned about this common problem) more clanking. So I found broken spring and made my own cct (carriage bolt, tap set, locknuts and seals. VERY EASY) I installed and tightened the mcct and the rest of the bike. knowing that the valves might be bent i still kind of hoped she would just miraculously run perfect. She started right up and would run as long as i could play the throttle. As well as the not staying running, she has a rythmic tap from same area.

I have read as many posts here as i can spend the time. I was wondering if this sounds like it is most likely valve adjustment or maybe the mcct is too tight. or maybe something else. and also to do the valve adjustment myself is the manual the best resource for me. Thanks for the help.................................
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Old 06-05-2012, 04:17 PM
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Yes bent valves, dont run it anymore till corrected.
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Old 06-05-2012, 04:40 PM
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is shimming the valves the only thing i need to do to correct the issue? And is there anything maybe that I should now about the process or should watch for? thanks again.
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Old 06-05-2012, 04:58 PM
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Originally Posted by BURNOUTS MC View Post
is shimming the valves the only thing i need to do to correct the issue? And is there anything maybe that I should now about the process or should watch for? thanks again.
No, not need adjusted,., they are likely BENT, and will need to be replaced. in bad cases valve guide, head, piston damage can be the result.
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Old 06-05-2012, 05:08 PM
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So how do i know that they are bent? Check the valve clearance or something else?
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Old 06-05-2012, 05:25 PM
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You can check valve clearance an indicator of bent valves, if bent they will be open...or large clearance (way outside spec)

a Leak down test would be the best way.
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Old 06-05-2012, 05:28 PM
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Pull the valve cover. Look at the clearance between the heel of the cam and the lifter. Most likely it's got a quarter inch or more of clearance. This is because the valves are bent and not letting it seat properly. This is also what's causing your tapping noise. Did you by chance check the cam timing? If not it's most likely 2 or 3 teeth off at least.

I had this happen to my bike 2 days after I bought it but on mine the previous owner was an idiot and left the front CCT bolts loose and the whole thing just came out! I had about $240 into mine for parts and to pay someone to install the new guides as I didn't have the correct driver or reemer and my guides were broke. I did the rest of the work myself. If you can't do the rest of the work yourself it's going to be a spendy fix!
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Old 06-05-2012, 05:33 PM
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sorry if i should know this but i dont know what a leak down test is. this is my first v-twin (not even sure that has anything to do with it) Also if it is
a bent valve is there anything i might want to do while the motor is open other than fixin whats broke.......?

I was just reading the manual and im pretty sure i can handle the fix, just a bunch of questions to get me there.
Thanks again..........................
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Old 06-05-2012, 05:36 PM
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yes i pulled the camchain off and corrected the timing. not sure how many teeth but it was roughly 1/4 turn of the sprocket off and both in front relative to each other....
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Old 06-05-2012, 05:50 PM
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Wow, 1/4 turn will bend valves for sure.

If you don't know what a leak down test is, that's not the route you want to take. Check the clearances for the easiest indicator, and of bent, start taking the head apart to inspect guides and piston.
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Old 06-05-2012, 06:05 PM
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Going to start taking head apart and going from there. Thanks for all the help. Ill let you all know what i find.
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Old 06-06-2012, 05:59 AM
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Quick write up on Leak down and compression tests
Leak down Test and Compression Test - ThumperTalk
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Old 06-06-2012, 01:11 PM
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working on the bike. down to the valve lifters. is there any way to get them out without the valve lapping tool. I tried the magnet but maybe they are jammed or the magnets not strong enough??? not sure could use some help thanks.
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Old 06-06-2012, 01:50 PM
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You may need a stronger magnet. The magnet I use can lift a 15 pound object off the ground. The engine oil takes up any slack and makes the bucket feel as though it is sticking Try turning the magnet while lifting and maybe a VERY GENTLE wiggle. The bucket should rotate easily and lift straight out. If it tries to come out a little crooked it will get stuck. Press down to make sure it is seated all the way and try again. Try to spin it with your fingers first to make sure it is free. DO NOT DROP THE SHIM when you pull out the bucket, it is small and can easily fall into unwanted places.
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Old 06-06-2012, 04:20 PM
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well i got the lifters out with a stronger magnet ( thanks beerhunter). I took off the head and have found out why my newly purchased superhawk is a newly puchased superproject. without taking the valves out it looks like all four are bent. They all look like they might sit at different levels, as well as maybe a little tilted. The piston has two divots where the valves hit the top by first sight look like they are about 3/32 in depth. and to top it all off the liquid in the cylinder (if you can see it in the picture) is ANTIFREEZE!!!! As far as i know i need to replace piston, valves, probably valve guides.

anything else......?
new piston for sure.....?
what with the anti-freeze....?
DAMN.............................................. ...................
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Old 06-06-2012, 04:26 PM
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pics
Attached Thumbnails Bent valves???-2012-06-06-17.24.51.jpg   Bent valves???-2012-06-06-17.23.39.jpg  
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Old 06-06-2012, 11:05 PM
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Yep looks like you did quite the number on it. Sorry to see that. Looks like all 4 valves are bent. You can get the keepers off the springs by placing a deep well socket on the valve spring retainer and smack it with a hammer. This will pop the keepers right out. Just be careful not to hit the walls where the buckets ride.

It's hard to tell in the pic of the piston if its really messed up or not. There are valve reliefs cut into the piston from the factory. Raise it to the top of the cylinder and clean it off real good and take some more pics. It may be just fine. The coolant probably just got in there when youpulled the head.

Once you get the valves out you can inspect the guides. Mine were broken and had to be replaced.
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Old 06-07-2012, 07:51 AM
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alright thanks a lot. ill let you know and post more pics.
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