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Discussion Starter #1
Been lurking here on and off for a while. This is my first post.

I bought a '72 K1 a while back. Vin is 2005751 DOB is 9/'71, which means it's a fairly early K1. It's something of a survivor. Just over 3K miles. Wiring is stock and never been molested. The engine has what I believe to be OEM aftermarket polished cases and no #. The head has a cam bearing, high lift cam and high comp valve springs. The seat and exhaust are the only parts I'm sure are not original. Please see pix.

I knew the bike was not running well when I bought it. Figured a cam chain replacement would fix it. It didn't. Carbon deposits on the head/piston tell me it had not been disassembled for quite some time. As in many decades. The screws that hold the cases together are like new. Not at all mangled. I'm positive I'm the first to take this engine apart since whoever put it together back when. Turns out, the intake rocker has some extreme wear, and the rings are shot. No wonder it only had 45psi compression. I have replaced both rockers, and currently having the jug bored one over, and ordering new piston and rings.

Previous owner told me the bike came from Nevada. I have some suspicions about it's history. Someone who knew what they were doing and the parts available at the time built this engine. Possibly a dealership as some kind of promotion? Or am I making too much of nothing?

Comments? Questions? Snide remarks?

Mark

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Welcome to Planet Minis! Betting that you have a replacement engine case from Honda. They would have been ordered from the dealership and did not come with a serial number. There are some replacement frames without serial numbers as well. I actually have a Triumph frame like that, with no numbers stamped, but otherwise identical. Nice bike!
 

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I was just looking at your pictures and noticed what looks like some severe wear on the rocker arm cam follower surface. Maybe it is just the angle, or an optical illusion, but the rocker in the foreground looks like it is ground out some?
 

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That's not your imagination. I've never seen a rocker that worn before. The cylinder has some wear too, but the 2 compression rings are shot. I don't know if you can tell, but look at the pic. Odd, if only because the engine didn't smoke that bad.
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It does have a hi-lift cam. Also, from the discoloring, it looks like that engine got a bit warm a time or two. Possibly run low on oil?

As for the jug, is it possible the piston stopped at that spot, and the bike was stored for an extended period?
 

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Ya, your bearing, in your pic, has the same stamp as the one from dratv. If you run that cam with stock/wrong springs, it could be what ate that cam follower.
How does the lobe on the cam look...it's gotta be rough.
 

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Ya, your bearing, in your pic, has the same stamp as the one from dratv. If you run that cam with stock/wrong springs, it could be what ate that cam follower.
How does the lobe on the cam look...it's gotta be rough.
The good folks at my local Honda dealership told me these are stock valves w hi comp springs. The cam lobes are another question. Seems to spin fine with the new rockers installed, but I'm no expert. I have seen that item on dratv. It's possible i'll end up ordering one. I have a .50 over piston kit coming from NE Vintage. My machinist wants to see it before he hones the jug.

Thanks much for checking in. I can see this thread had drawn a few pair of eyes. Thanks to all!
 

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