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Rewiring K2 with later high beam switch
the-chauffeur:
Thanks chaps - and special tip o' the hat to KC for the 2-stroke oil warning notes.
Having had a sit-down-and-keep-it-together session, I set to pulling the top end apart to try to trace the blockage. Much to my surprise, it wasn't the jet - that turned out to be fine. With the head off, I cranked the kickstart to pump oil through the oil passageways and found that there was nothing coming up the RHS cylinder stud that feeds the head. Barrels off too - and they're fine in case you were wondering - and stud out, and the blockage turned out to be something (I'm still not entirely sure what) in the crankcase jet that feeds into the RHS stud gap.
Spiked that hole with a long, thin pokey stick and something gave - I'm damn sure I did that to both sides before I started reassembly, but obviously not hard enough - and cranking the kickstart pushed equal amounts of oil through both L and R feed holes. I pumped some cc's though just to make sure it wasn't going to jam up again, and then took the RHS oil gallery cap off so I could have a look along the length of the engine. Nothing obviously amiss there, but just to be sure I made a cleaning out stick from of a long piece of thin threaded rod with a nut on the end, and covered the nut with a small piece of cloth (I needed something that was just wide enough to feed in without touching the sides and pull out again whilst resting on one side to pick up any junk).
Again, nothing too sinister there, so I'm kinda concluding the blockage was a couple of beads of vapour blast media that had stuck together and wouldn't shift; the sharp poke broke the surface tension between them and they fell apart. The gallery was shiny and empty after the rod cleaning, so once the new head turns up, I'll clean and modify the towers, and mount them without any other cam train parts. I'll then use the kickstart again to make sure the oil flow is fine. The only other things I needed for reassembly were a new base gasket, some of the round rubber pucks that go under the cam towers and the teeny-tiny o-rings that go round the jets and blanking holes at each end of the towers. Having rebuilt the engine three times now (don't ask), I had spares knocking about.
Rockers and rocker arms have been polished and I now can't really tell the difference between the ones that were on the RHS and the ones on the LHS - thank God for hardened faces/rods. Looks like the only real damage was to the cam shaft journal and the RHS tower, probably 'cos I ran it for such a short time. Yeah - it could have been much worse (Pete - the same self-removing cam sprocket bolt trouble as yours caused this most recent rebuild; mine cut into the rocker cover and sent metal bits all through the engine . . .).
And I cannot begin to explain just how much time, effort and pain the removable frame section has saved. The ability to remove the top end with the engine in the frame meant that I could pull off some bits, diagnose the trouble, put most of the bits back on, all without having to disassemble half the bike (or scratch the frame in the process. Equally, I can test the oil feed with the kickstart, pump and tank in place; that'd've been a hell of a job out of the frame. Right now, the bike is 95% complete - I only need to add the head components and rocker cover and we're off again. Without any fear of contradiction, that frame mod kit has already more than paid for itself.
Not bad, huh? Didn't exactly turn out nice again, but this time it's much easier than I thought it would be . . .
Bryanj:
Years back had a man who ground the cam journals round again and machined half round Phosphour Bronze bushes that were pegged into the towers---It is possible so DO NOT bin anything, at some time in the future those bits may be re-used!!!
the-chauffeur:
. . . 3 . . . 2 . . . 1 . . . and we're back in the room.
All done. Everything's buttoned up and I ran the bike this morning to see how we were going - leaving the exhaust valve caps off 1 and 4 to check the flow. Got it started and had a quick look with a torch - yup, got some flow going on there. Stood back to take the choke off and generally admire the handiwork before noticing the oil pressure had charged itself up properly and oil's spraying out of both caps. Don't think I'm gonna have any problems with the valve train being oiled properly . . . having said that, a quick ride has revealed the top is perhaps now oiling a little too well 'cos there's oil coming out of the upper fins. Guess I didn't use enough sealant on the pucks and on the ends of the bolt threads. Still, sorting that out with the top section off should only take about an hour and I'm gonna replace the head with the newer one sooner or later.
I gotta also figure out how to get the engine to idle between the two points where it seems to gravitate to - either 600rpm or 1,400rpm. I thought the timing was right and the carbs were synched, but I guess I'll have to try all that again. I have a feeling something's blowing/not firing right as well, but again, that's easy enough to check out.
Getting there - again . . .
the-chauffeur:
Hmmm. I spoke a little too soon.
There's good news - jetwashed the engine and it turns out the stuff on the upper fins was just residual oil from the headwork that had dried and then solidified when it heated up. There's no leaks from the top end.
However, the not-so-good news is that the joint where the barrels meet the crankcase at the front of the engine (i.e. around the base gasket) leaks. Quite a lot. I'm sure I had this happen before when a shop put the engine back together. That time one of the rubber rings that goes round the base of the individual cylinders had been poked up too high into its recess, causing the leak and the oil pressure warning light came on. This could be the same deal (without the oil pressure light) - or it's the areas where the surplus oil drains back into the crankcase from up in the head. Either way, it's all got to come apart again (take head and barrels off). Arse it. Oh well, I'm getting used to it now.
There's also white exhaust coming out of 3 and 4. They're the same end where the camshaft lunched itself, but I have a feeling they're exhaust leaks (the joints from the headers to the head aren't exactly wonderful). It also wouldn't surprise me if the valve seals had hardened with overheating and now leak a bit. Guess I'll have a look see while I'm in there - again.
UK Pete:
Neil, the cost for gaskets and o rings alone must be mounting up, still as you say you are now getting used to taking apart and reassembling the engine so time wise it should be a doddle
When i build engines i use blue hylomar or copper grease on the gasket surfaces depending on where it is just to aid sealing, it seemed to work a treat on my F2
Anyway chin up mate your get there in the end, i am hoping your next post on the subject will be full of joy, you deserve a bit of luck
Pete
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