Well, the fun came and went.....

Energy One

spadesluck

Active Member
I was riding the bike last week to work and heard a metal noise then loss of power immediately. At that point I could tell I was running on one jug. Turned around and limped it home. Just got done doing a compression test, front is 150+...rear is a big 0...:down: I pulled the rocker box cover off to see if I could see anything apparent. Everything looks to be in order. Only thing I can think of is my rings gave out. (I know I know, should have replaced with the rebuild of top end) There is no other motor noise, just no power/compression.

Needless to say my riding for the summer is over. Not going to tear it down cause we are moving in July. Will handle it when we are settled back in our new place/base.
 

Brew

Troop Supporter
Sorry to hear the lousy news! I hope you can get her back on the road soon after the re-location...
 

bigdogtech01

Well-Known Member
Total loss of compression is not the piston rings. Most likely you lost a valve. With having the TP rocker boxes, the valve guides probably are worn to the point of failure, causing the valves to break.
Let me know if there is anything I can do to help you out :cheers:
 

grizfish

Active Member
Just pull the head. Confer with bigdogtech01. He can get you back on the road for a month of riding before the move.

My last battle with a broken valve beat up the piston on my shovel. Had the head rebuilt and got back on the road without doing anything to the piston. Just a few dents and dings on it. Didn't seem to make a difference with the way it ran. Lasted me until the next top end rebuild.

However, I shut her down when the valve dropped. Didn't try to drive it back home.

Good Luck
 
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spadesluck

Active Member
Did you rotate it with the rocker covers off to see if the valves work?
No I have not done that yet, but I will just to see.

Total loss of compression is not the piston rings. Most likely you lost a valve. With having the TP rocker boxes, the valve guides probably are worn to the point of failure, causing the valves to break.
Let me know if there is anything I can do to help you out :cheers:
If you look down a few posts from this one you will see that I just got done doing my heads, ported, polished, and cut down for compression. I have a brand new top-end as well. Replaced the TP's with S&S box's and arms and new lifters. I am also running a 600 cam.

The bike ran great and did not show any signs of potential breakage. Just out of the blue.
 

spadesluck

Active Member
did you put in new compression releases???? one may have stuck open
They both spring back when I push on them. Nothing seems to have fallen apart on either of them. Also, would they be stuck open after the fact the bike had already been running? I would not think so.
 

knucklehead

Member
This happened to me once. Turned out one of the push rods came loose. Worth checking.the metal noise you heard was most likely the loose push rod rattling around.
 

spadesluck

Active Member
Under the guidance of a friend I hooked up my compressor through the spark plug hole with the rocker arms off the head to find out where the problem was. Turns out the exhaust valve is the culprit. It sounded like my bike was trying to play an instrument with all the air going out the exhaust. :down: So now I am going to remove the head and see what exactly happened at this point.
 

bigdogtech01

Well-Known Member
Who did all your motor work? Sounds like they did something wrong and possibly a clearance issue if they cut the heads/cyls down to bump compression up :bang:
 

spadesluck

Active Member
I am going to just take it apart first before I make any assumptions (I could have put the cam in wrong, who knows). I am sure this is just a weird accident that is no ones fault. The bike has around 500 miles on it since the rebuild, so its probably just a matter of a part failing.
 

spadesluck

Active Member
I was able to pull the head off a couple days ago. I definitly had piston to valve contact. It looks like it hit only once and bent the valve over. Sent the head back to get fixed up. I will then take more caution when adjusting the lifters the 2nd time around. Lessons learned.
 

liferider

Looking forward to retirement
Who did all your motor work? Sounds like they did something wrong and possibly a clearance issue if they cut the heads/cyls down to bump compression up :bang:
How much did they take off when they Decked the heads? I did .010 on my EVO and that was enough to go from 8.5 /1 compression up to 10.0 /1 and then put in the pistons Kendall Johnson sent me brought me up to 11.0/ 1 compression. Also Kendall said since this was on a tour bike he suggested leaving the smaller valves in instead of increasing valve size, this would create more torque for a tour bike instead of raw HP. Kendall did all my work and with him being the King of V Twins, how could I argue? So I did what he said. We also cleaned up the intake and exhaust. It's increadable how much metal gets milled out and how rough the surfaces are from HD and how much metal gets cut out and how smooth they came back!!!!
 

05chop

Well-Known Member
no picture of broken parts so my guess is valve keeper failed but you said exhaust valve bent over so was the valve still in one piece ? just curious
 
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