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Chevy454
10-16-2005, 06:31 PM
Last night one of our 250Rs would not start, so we did some checking. Seems the stator/alternator had burned up. We replaced the alt. and rectifier, still would not start, so we replaced all of the electrics from a running quad, everything. CDI box, stater/alt., flywheel, rectifier, wiring coil, etc. Still will not fire. And here is the strange part. Regardless how hard we kick it, and how many times, it will not fire, UNTIL after you stop kicking it. With the plug out you can see this happen. With the plug in, will not act like it wants to start, or even kick back, until after you have kicked it. We even tried another CDI box and 3 coils off of a quad that we had just ran.

BTW, we check the parts with a meter and everything seemed to be within range.

It is a 350pv, but do not see where that should be a factor.
ESR350r
10-16-2005, 06:47 PM
check your compressions. then try knocking your plug gad down to 18 thousands.
Chevy454
10-16-2005, 07:36 PM
Compression good, plug gap at 19.
wilkin250r
10-17-2005, 10:49 AM
I see only three possibilites.

1. Did you check the wiring? If you have a bad kill switch, or a short to ground, or an open wire, you could swap all the other components you want, and it still wouldn't work.

2. If it's not the kill switch or wiring, and you did indeed swap all components, then the only solution would be the quad engine and chassis itself. That would mean a bad ground path. The fix would be to remove the engine, and clean all mounts with a wire brush down to bare metal. Then, the same with all the stator mount areas. You need to ensure a good ground path.

3. Or, the only other possibility is that you made a mistake somewhere in your previous troubleshooting.
ground_zero298
10-19-2005, 05:02 PM
Did you ever figure it out?
Chevy454
10-19-2005, 07:32 PM
Originally posted by ground_zero298
Did you ever figure it out?


Nope. We tried everything, including parts from a running quad, but nothing worked. So today we installed a new PVL system from FTZ. Seems to have cured most, if not all, of the problems. We will know this weekend as we go racing.
beerock
10-20-2005, 05:44 PM
the Pvl ignition eliminates alot of griefs of the stock R ignition, or cr250 for that matter. no on off box no cdi box just set the timing up and turn the motor over . the only thing that could make it not work is if the kill switch shorts.

chevy454, . I know the one from FTZ is the digital PVL and it gets you all the power band availible out of the motor because of the digital retard and advance feature. its great!

the stock 250r and analog pvl have there own timing and retard on it but it is very slow compared to the digital
wilkin250r
10-20-2005, 05:59 PM
I don't see that possible.

You swapped over ALL ignition components from a known working unit, and it still didn't work.

Yet the PVL does work?

That's ridiculous. That contradicts every law of physics I can think of. There HAS to be some other explanation.
beerock
10-20-2005, 06:33 PM
Originally posted by wilkin250r
I don't see that possible.

You swapped over ALL ignition components from a known working unit, and it still didn't work.

Yet the PVL does work?

That's ridiculous. That contradicts every law of physics I can think of. There HAS to be some other explanation.

its magic:D
Chevy454
10-20-2005, 07:02 PM
Originally posted by wilkin250r
I don't see that possible.

You swapped over ALL ignition components from a known working unit, and it still didn't work.

Yet the PVL does work?

That's ridiculous. That contradicts every law of physics I can think of. There HAS to be some other explanation.


All we can figure out is, the big bore needed more spark. The running quad was a 265 National, while the one we were trying to get going was a high compression 350PV engine.
wilkin250r
10-21-2005, 10:21 AM
But if you pulled the spark plug out to look for spark, it shouldn't matter.

Also, if that was the case, closing the gap should have fixed the problem. It seems impossible that you would need a gap smaller than 19 thousandths.

The only explanation I can see is that the ignition you swapped in was also weak, or you had a bad ground path.

But anyways, you got the problem fixed, that's all that really matters.
ground_zero298
10-21-2005, 04:18 PM
I can't offer any more help than these other guys gave you but I hope you figure it out. I know what it's like when you have something that should run but won't.
Chevy454
10-23-2005, 02:06 PM
The bike is back up and running strong, winning both the 2-stroke class and the drag racing. In the drag racing lots of modded bikes, 400EXs, 450s, Banshees and even a couple of highly modified 700s.

We fouled a plug late in the evening, and the bike smoked a little more then usual, but we are guessing that had to do with the temp. drop. Went from 70s to 30s.
beerock
10-23-2005, 02:57 PM
Originally posted by Chevy454
The bike is back up and running strong, winning both the 2-stroke class and the drag racing. In the drag racing lots of modded bikes, 400EXs, 450s, Banshees and even a couple of highly modified 700s.

We fouled a plug late in the evening, and the bike smoked a little more then usual, but we are guessing that had to do with the temp. drop. Went from 70s to 30s.

if it went from 70 degrees to 30 degrees the bike would lean itself out