Kawi2strokes.com Forum

Hi,

Hope to get some advice on an issue with my H1. It's an early euro model H1 with points.
Long time since I've posted btw...

I have a Starfire CDI unit, one of those that uses the points as triggers. Here is how it runs WITHOUT the unit installed:

There is a misfire and flat spot at a certain rpm. It moves up and down the rpm range relative to the points gap, the smaller the gap the further up. At stock gap it occurs at around 4.5-5K, now the points are set to 0.2mm and it occurs at 6K rpm. I can push it beyond this but it will run erratically. It is most noticeable under load, but is still there regardless. It can idle fine but suddenly the idle rpm drops, its just as the spark gets weaker, before it suddenly pics up again and idles fine.
I first suspected bad or floating points so I replaced them but there was no difference. Then the condencors was replaced, then the entire stator. No difference. The charging is fine it seems, but I have not been able to measure it under load. The carb setup has been the same for a long time, also before this occured. It ran quite well with the stock points setup before this issue.

Then I installed the Starfire CDI unit. Problem is gone, more or less. The bike runs much better but I still feel there is something that holds back its full performance.

Earlier this summer there was a failure with the Starfire unit, but its easy to bypass by just reconnecting the leads back to points. But then, of course, it was back to the same issue as before with the points and misfires. I'm now waiting for the unit to arrive after repair (Starfire-Dayle is a very nice guy and offers excellent service, he found the fault, fixed it and sent it back, no problem). But I'd like to cure that initial problem before I reinstall the unit.

As I've replaced or checked most other things, I sit back with the coils. I don't think all three are bad but if one is weak and delivers a weak spark under load it would affect performance. Perhaps one or more coils doesn't pick up enough charge from the points. Smaller gap means more dwell time for charging, in my head that makes sense as the misfire moves up and down the rev range relative to the gap. But when the CDI unit sends a much stronger charge to the coils they keep up, although perhaps not 100% but enough for the bike to run quite well.

Sooo... any opinions on this? I asked Dayle and got some advice but I'd like to hear if others have had the same issue with points ignitions or any other opinions on this.

I consider ordering some new coils from HVCcycle but with shipping and all it is an expense so I'd like some more input first.

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H1, T500, T350, T250, GT550, RS100, Sachs

Not that I have ever heard of this problem before but I'd replace the coils. Any coil designed for points will work... automotive, Moped, outboard, whatever. Primary resistance should be about 3 ohms. The Starfire unit will work with about any coil.
The only other thing in circuit is the plug caps & wires.

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Answers are here: http://kawatriple.com/

Check your plug wires in the dark, mine was arcing on the cylinder head one night when I was leaving and noticed it.

I had an issue similar to this on the old Suzuki GT.
It turned out to be the wires from the points ran up the frame and had connectors there. Those connectors had rubber boots and all but were still jumping (grounding) to the frame intermittently. Good ol electric tape solved it.

The only way I ended up figuring it out was I was messing with it in the dark and actually seen the spark jump.

So thats a +2 on looking for an arc in the dark.

Thanks for input folks. But would't any grounding to the frame lead to misfires at any rpm range? The problem here is that it moves up and down the rpm range relative to the points gap. As it is now it runs smooth up to 6K, the point gap is 0.2mm, which is much to small really. But at stock opening it occurs around 4.5-5K.

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H1, T500, T350, T250, GT550, RS100, Sachs

Well Knut, I guess the only thing left to try is the coils.... you have done everything else!! It does appear that it is an electrical thing, and interestingly cured by fitting the CDI. Its a long shot, but if the bike is hovering near the power band when this occurs, suggesting a higher voltage requirement at the plugs, would one be breaking down, or does it seem to be all three? You could try shoving an AM radio in your pocket with earbuds, tuned off station. This will allow you to listen to the spark while riding..... may help isolate the cause.
Edit.... the fault with the CDI unit was a blown SCR.... this also could point to an ignition coil problem. I neglected to notice which cylinder when I was repairing it, silly me.... this would have possibly helped you isolate which one.

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http://3cyl.com/mraxl/starfire/starfire.htm

Another board member was experiencing a similar problem with non-stock coils.
Replacing them with stock coils made a big difference.

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Answers are here: http://kawatriple.com/

I don't know if it could be one or all three. All three wouldn't break down at the same time, unless there is something between the points and coils affecting all three, but all that has been checked. So if it is a coil issue I'd believe it would be one that is weak.
It seem to occur when there is a higher voltage requirement at the plugs. In my head I just think that when the points are set to a larger gap it's less dwell time for charging the coils. If they are weak they need longer dwell time and when set to a smaller gap they can keep up more until a certain point. And when the CDI unit is installed they get an even higher charge so they can keep up even more. Just my theory...
Will try the AM radio thing, could be interesting.

I will order a set of coils from HVCcycle, they have the same physical dimensions as the stock coils and measure 4 OHM resistance. I'm replacing all three as a matter of principle.

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H1, T500, T350, T250, GT550, RS100, Sachs

It was the coils that caused problems.

I got my new ones yesterday and installed them today. Took a ride first without the Starfire-unit connected to check, and it ran smooth and well, no misfires. So I connected the CDI unit and it ran even better
When it hits the redline there are some slight boggering, but I guess that can't be avoided with points. It doesn't go past the line but that's not important. It runs well now so I'm happy
Thanks to those who chimed in here and on email.

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H1, T500, T350, T250, GT550, RS100, Sachs

Good news there Knut!! I wonder if the dodgy coil was responsible for killing the CDI? I guess we will never know. Those 4 ohm coils are perfect for the Starfire, and they should last pretty much forever. Very good outcome.

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http://3cyl.com/mraxl/starfire/starfire.htm