No spark Yamoto GY150
 

This bike has worked absolutely perfectly for 2 years now, until 2 days ago.

Took the little guy riding on our 10 mile loop, and 2 miles into the ride, I hit a bump, and then it died.

Ended up pushing 2 miles back through sand trails.... :evil: Anyway, I was afraid I blew the engine, as it acted the same as when I blew up my CR250.

I got it home and the problem is no spark. Thought it was odd, 3 day old plug..put in a new one, and still no spark.

Coil still seems ok when I put the volt meter to it and check for resistance, but there is no power getting to it on kick over. Oddly if I put the volt meter to the two wires on the kill switch and kick over, it swill spikes up properly, and the switch still kills the power when I hit it. So the motor is still producing power, but it isn't getting through the black CDI box to the coil...I think that is the problem, anyway. I don't think there would be any other way to have power to the kill switch and not to the plug.

So my question is can this CDI be rigged up with just any CDI system or does it have to be the specific one?

Thanks in advance.

So you say you hit a bump and it died.

have you checked to see if any wires got pinched/damaged/unplugged some where ?

I've checked just about every wire I can find, everything seems fine for physical damage, so I'm thinking it's electronics in the CDI or maybe some sort of sensor. Meanwhile it's in about 400 pieces in the garage... I miss riding.

Ok, I still don't know for sure, but I think it's a problem with a sensor inside the engine.

When you take off the chain guard part of the case I find one connector with 6 wires that goes to a little black thing bolted to the motor. This black circle has an "L" shaped knob that sticks inside the motor and into a bolt with a groove in it. This connection must be for lights that I don't have, because the connector is just tied up but not hooked to anything. When I take it apart, and hook the meter up to it and spin the thing by hand, it produces power based on how fast I spin it. By hand the most I got was 0.4 volts.

That seems like at engine speed it would produce lots of power, but again, it has no connection ,so it isn't doing anything.

Next are 6 more wires that go through a rubber grommet into the engine case. Kicking the engine over, no combination of wires produces more than 0.1 volts, so I think maybe these are the problem. Now the question is WTF is the first sensor that isn't hooked up, and 2nd what do those wires that go through the grommet into the case hook up to?

I know I rambled, sorry ;)

I appreciate any help at all, the little guy is upset about not being able to ride.

fuse? :oops:

Picture's worth a thousand words. There's 2 sensors in that area, 1 with 2 wires to it should be a flywheel TDC sensor. Thte flywheel sensor sits next to the flywheel. There should be very minimal clearance between the sensor and its pickup area on the flywheel(like a sheet of notebook paper folded in half clearance.) The other sensor should be the tranny sensor. It may have several wires to it if you have a shift/gear indicator. It's to the rear of that area, nearer to the countershaft if I remember correctly.

Bear in mind either one of those sensors can cause a no fire issue.

Ok, got a couple pics, I forgot the flash on the inside pics, so bear with the graininess...

http://img403.imageshack.us/img403/2...e001wt0.th.jpg
http://img168.imageshack.us/img168/6...e005pb6.th.jpghttp://img168.imageshack.us/img168/8...e002hs0.th.jpg

I dunno, I suspect this bike has become a future junkyard resident...I don't have time nor money to screw with this a whole lot right now with college starting next week.

You mentioned the kill switch.

Have you disconnected it to eliminate it as possible cause? May be that some internals inside came loose and are shorting it out.

Allen

It's running again. I have no idea what happened, must have been a loose connection. However I think I screwed it good in the hunt. Took the case apart to look inside and when I put it back on I apparently stripped one of the bolts. Now it runs, but the trans makes a whining noise and it seems to have no compression. I don't know if it's ruined or if it will be ok if I can get it sealed properly again.