mis-matched cam caps

I have an interesting issue on a head i'm working on for a friend. The head was from an unknown bike so of course I want to check everything. It was in a very dirty state, probably sitting for years collecting grim until he bought. It appears to be a KZ1000 by the caps. We ordered a set of cam bushings (OEM) and I checked the clearance with Plastigage and those were from just under .002 to just under .004 so that is good. I slowly installed the caps while turning the cam and they began to lock. So looking at things it appears cap 2 and 4 are tight towards the front of each cap. I installed 1 and 3 by themselves and the cam turns freely. But when installing 2 and 4 they begin to lock up. So just out of curiosity I turned 2 and 4 around (arrow pointing backwards) and the cams rotate freely. Humm. The intake cam has just the slightest drag in one spot while turning but I can turn both with one finger. As you will notice the intake took a another nudge to rotate on the clip but not always.

So for all you guys that have worked with mis matched caps would you run them with the 2 and 4 turned around. Im pretty sure I would have damage if I were to run them in the correct orientation. 

vimeo.com/1141546038?fl=ip&fe=ec

 

Are you able to bolt the head down (may have a twist that will correct when in place) and see how it is then 

As soon as I get studs but looking at the tight spot which is just above the center line of the two right caps I would think it's not twisted. 

I had to do that with the head I'm running now. Works fine. 

Quote From SWEST.
I had to do that with the head I'm running now. Works fine. 


Meaning you had to turn the caps around.?

Might be/probably moot but were the caps and head bearing surfaces nice and grime/imperfection free? Don't know how equipped you are but try some of this stuff, messy i know! Put some on the newly purchased shells after in place, assemble, turn cam in place several times, times, times. Disassemble and note the pattern of blue removed and location. Or, assemble without the shells and note any cap to head joint mating overlap. Your fingernail will snag it. If wear is consistent high/low then head is warped or cam is not true. If where the cam shells meet it either still warped cams or mismatched cam caps to original line boring.     

Yes I will be trying a few different things. The parts were extremely clean. Cams have almost Zero run out (needle hardly moves). If the head was twisted one would expect both sides to have issues. But I will be checking possibilities.

wrote:

Quote From SWEST.
I had to do that with the head I'm running now. Works fine. 


Meaning you had to turn the caps around.?

Yes, the junk head I got for $20 came without them. I found 3 but one wouldn't work so a member here sent me one then another from a J head. They would only work backward. I etched them accordingly. I used a hone and plastigauge on the shells to verify fitment. The head was just redone but scrapped due to broken fins. 

 

Mark the caps for the next owner

When I do all my checks and satisfied that they have all the necessary clearances I plan to remove all marking and have them laser engraved with arrows and numbers. it would be a bummer somewhere down the road to have someone check valves and say hey look the caps are backwards and switch them around only to create a major problem. Besides as I get older (71 now) I may not remember what I did next year and reverse them 

Only my opinion but what ever you choose to do I would do it with the head bolted down and no valves fitted (use an old gasket)

Interesting story here, with equally "interesting" solutions... When you consider that the camshaft bearing bores of these cylinder heads are drilled WITH the bearing caps already installed, you quickly realize that only the original bearing caps fit perfectly: Everything else is trial and error, or a lot of machining and shimming, and the result is often questionable, at best a successful improvisation. Just my opinion and experience on the matter.


I've seen, or even owned, many cylinder heads that didn't come with the matching, original bearing caps. It was always a "makeshift solution." At best, only the height was off, which could be corrected with thin shims. But if the inner circle was misaligned, there was little point in trying to fix it. Experience teaches us: it's best not to buy cylinder heads without the correct matching bearing caps.


But anyway:

I wish you much success with this operation and all the best!