Alrighty, here’s what I know so far.
The bike in question is a 1986 XR200
Last year I replaced the piston/rings/valves, cam chain , and gears (cam and crank).
The bike has run smoothly since November of 2002.
Since this problem has started, I’ve replaced:
The last time I personally rode the bike, before the trouble started, it was easy to start, and even pulled me around OK. :silly:
Last Saturday, Squeaky went on a ride without me, and when she came back she complained that it was very hard to start, but otherwise ran OK. Sunday, she went out for another ride, or I should say tried. The bike would not start.
Here’s where I get back into the picture. I kicked until tired, and barely got a burble outta the old girl. I took a look at the plug cap, and the plug. The cap was cracked, and the plug had seen better days. I suggested changing both of them and trying again in the morning.
The next day, Squeaky obtained the parts, and I installed them. The bike fired up, but was smoking, first black, then whiteish smoke. The smoke did seem to clear out a bit after a while, but, when I let go of the throttle, the bike would immediately die. I took of the ignition cover, and found that the pickup plate was loose, and was probably(definitely) making the timing bounce all over the place. I centered the pickup, and started the bike again. It now starts up famously(if I crack open the throttle), but is still very choppy, and almost like a surging sensation.
At this point I decided to do what I probably should have from the beginning. Clean the carb.
The bowl was coated with a white powdery substance (fairly thick in places. As I was cleaning I found the pilot jet to be completely blocked. When I was finally able to see daylight through the jet, it was all egged out. A replacement jet was in order.
Today I installed the new pilot jet, and fired up the bike. Still I’m getting no idle. The idle screw is in as far as it goes.
The odd thing is, that at a stand still if I bring up the RPMs, the bike will almost sound like it is cutting out intermittently. But, when I rode the bike around the field a couple of times. It felt just fine! It would pull me out of corners as well as it ever had. There was no hesitation, no misfiring, or backfiring. Again, though, as soon as I let my hand off of the throttle, the engine would die.
I had work to do on the farm, so I left it like that. Squeaky came over to me and showed me the air filter. It seemed like she may have been a little over zealous with the filter oil, but nothing that would make me expect the type of symptoms that this bike is displaying.
At this point, I am stumped. I really don’t know what the next step should be in my diagnosis.
The intake boot from the air filter does have a crack in the rubber where it seats on the flange of the carb. But that it is not cracked far enough to be past the flange of the intake. I suppose to be sure, I should replace it and probably will.
Any ideas people?