Tuesday, May 5, 2009
I tried starting it obviously. Of course I wanted to ride it around if I could. The previous owner said it had not been started in 2 years, which was beleiveable, as oil was leaking out of seals, and when gassed up, the carbs leaked as well.
Finally I get a chance to start ripping it apart. My mechanical experience had mostly been on the 1992 Chevy S-10 and the Yamaha Zuma scooter, which I had put a carburetor and 70cc kit and stuff on. So this was like a bigass 4-stroke version of that, basically. It came with a manual so I couldn't screw anything up too badly. I cleaned the carburetors out, reinstalled them, got a cheap champion spark plug just in case my NGK was bad. Checked for spark, which I appeared to have.
I kicked the hell out of that bike, and I never got much more than a sputter. One day though, I got it to run for a while, and it smoked badly, misfired, and died. Later I would get it running long enough to ride it up and down my gravel driveway. What a tease! It had so much power that my 50cc-scootin' ass could hardly beleive it!
I had to have more. I just could not get it to start, so I began to check for other mechanical anomalies. I found out I didn't have spark anymore. I found out that I was hissing compression out of the carburetors. I had no way of knowing anything about the right amount of compression for this bike because I had no expreience with it in it's running form. There was no way to kick it over and know that it was way too easy and therefore it lacked compression, but after suspecting this, and telling some other XL600 guys that I could crank it right through the compression stroke with just my hand on the kickstarter, we knew something was up.
I tried a trick my buddy Sam Caldwell, and old, curmudgeony machinist about town told me about. With the cylinder head removed, I positioned it with the exhaust ports facing skyward, and poured gas in to see how well the valves sealed. Not very. Same test on the carburetor side revealed even worse-off valves. I had a machinist at an auto parts store look at it, and we dismantled the head. We found the valve seat to be loose on one of the valves, and he suggested knurling it and pressing it back in with some red loctite.
I never want to trust just one source of information, so I told this to Sam Caldwell, the curmudgeony machinist. He said that this was a risky proposition because the heat transfer properties of that steel valve seat to the aluminum head block would now be concentrated on those tiny little knurling points instead of the whole surface area. The tiny little points would get hotter becauase of less ability to get rid of heat through the aluminum, so it would get loose and fail more readily.
So now he had me good and scared. I didn't want to get the seat replaced since he told me that the way that they do this at the factory is probably with heat and liquid nitrogen. A shop could press fit it or do a less extreme temperature and possibly not press it in hard enough. I also didn't want to go with a used head; what if the previous owner had overheated it and the valve seat was on its way out?
So in one of my last transactions with Bike Bandit, I bought a complete head, OEM. It was wierd too, it looked like it had been made recently because the box did not look like it had aged from 1983, but the head was indeed mostly the 1984 design: 5th valve ith functional burp chamber, no reed valve equalization between the intake ports like on the 1983 (direct instead) and no pain-in-the-ass o-ring cap on one of the head bolts.
When I had asked via e-mail what the part number for the "head kit" included, since it was vague in the schematic, I was told, "everything needed for a complete head". It was just the block, valve guides, rubber intake manifold, and one head bolt, I guess to replace the one that went under the now-superceeded o-ring cap. I tried to get them to send me what they said it would include, bt they would not budge. I later found out that I overpaid by a hundred bucks or so, and now I use the Babbitt's website in Michigan to look up Honda numbers, and order from Zanotti's in Pennsylvania. I could use any site selling OEM parts to get the numbers from, but Babbitt's has the second best prices, a low price guarantee, and they are not Bike Bandit, so I don't have to look at their annoying lies or extremely high prices next to the part numbers. Zanotti's does not have a parts lookup page with pictures, but you plug in the part number and they come up with a low price and they order the part for you.
Anyway, I get the head, bitch about missing parts, get the valves and valve springs, anfter getting one wrong spring and a few e-mails back and forth and some more bullshit with Bike Bandit (I still had not learned yet) I got the head together and the valves lapped in and re-sealed. I got the cylinder mic'ed and found out I could get away with hone. The piston had been ruined, so I'd ordered one of those, a wrist pin, and a ring set. I finally got it all back together, and Bam! I'm riding this big-ass thumper down the road, barely shifting it correctly.
After only my first day of riding, it wouldn't start. I had to wheel it home from the local music venue, a real workout since this is a 300lb bike. After some diagnosin' around, I got a new stator and it fired right back up. Time for some hooligan riding!