K75 difficult to start, runs extremely rich

[Laitch]

Laitch -- I get 0.0 when touching the meter's red and black leads in Ω mode, and OL when they're not touching. The resistance between 10 and 5 is OL, and the resistance between 5 and 13 is 0.0.
It is a little curious that my old meter was showing a resistance reading between 10 and 13 and this one has only ever shown OL. Unfortunately I already gave the old cheapo one away.

There seems to be a fault within the control unit although I like the idea of finding a testing instrument that gives the values that you want if they can't be found any other way. 

[bast1472]

My meter started working again. I'm not sure what the issue was, but I believe I was 100% able to verify the connections between the coolant temp sensor, ECU, and ground connections. The sensors themselves also appear to work fine, showing ~2200 ohms at ambient temperature.

I dug into the airbox and checked the function of the intake vane/valve thingy and it was moving freely. I did notice a ton of corrosion on the pins in the port on the side of the plenum thing. I gave those a good cleaning before reassembling, and the bike fired up effortlessly! I let the bike idle and warm up for a bit as I still needed to burp the coolant after refilling. It was smoking quite a bit at first, which I assumed was all the gas from my repeated attempts at starting it without air over the last few months, and the smoking mostly went away after a couple minutes. However, after 5 minutes or so the bike started to struggle a bit. I'd give it some throttle and it would pop as the revs came down. Eventually it was stumbling terribly and died. No overheating light and I don't think the fan ever came on. After letting it sit for 20 minutes, I started it again and it ran better, but after a minute or two of warming up it started to succumb to the same conditions.

I took the bike around the block a few times and it was really struggling. I'm not competent enough to say if it was running lean or rich, but it would hesitate to accelerate and felt really underpowered, and wouldn't rev past 5k RPM or so. I'll try starting the bike cold again tomorrow and see if it repeats the same pattern of firing up and running happily before warming up and running like crap.

[Martin]

Warm the bike up to temperature and with it idling at 1000 RPM press the green stater button. If the revs rise the bike is running lean if the revs drop it's running rich.
Regards Martin.

[bast1472]

Hi Martin, unfortunately I couldn't get it to idle at 1000 RPM. It's pretty reliant on having the "choke" engaged, but after letting it run for a minute or two, I can turn the choke lever off without it dying, but it idles weak around 500-600 RPM. Pressing the starter button had no noticeable effect on the idle at any point during the few minutes' warmup. I'm thinking of getting back into the air box and giving that electrical connector more cleaning. Do you have any other suggestions?

[bast1472]

I ended up taking the bike to a shop, and they tested the spark plug wires for continuity, one of which was very low. They replaced the spark plug wires and it seems to run fine now. I had previously checked to see arcing from each spark plug but it might have been the way I had the wires twisted that allowed it to work momentarily, but when the spark plugs were installed apparently one of them was not sparking. Thanks for all the help and ideas!

[Laitch]