Liquifire: 80-81 VS. 82-84?

[Norton]

Kenny,
I will take your advice and get on the phone one evening and share what we need and have learned with Hewtech. I prefer to use e-mail but if he has a history of not using it, "he" must not like it.

Kokusan Denki Co. made the HSRI for Kawasaki/Deere (in Japan). They have a web site and still are in the mag ignition business for many small engines. I have been told that the first use of electronic timing control (besides engine starting) was used by Polaris in the RXL oval racer. Course nowdays it is common place in sleds. When you get into these kind of questions one wonders who did the R & D in the day with so many parties involved? Deere, Kawasaki, Kokusan, or even Polaris.

When I visit with vintage sled guys I often find that they can tell you what piston will interchange with different engines but what goes on inside the CD box, well that is magical. (-:

keith

[JDT]

My thoughts on this delema would be rather than reinventing the wheel, find a common and currently available ignition box that was recently used or is still being used.

I think that we would be on the right track going with a Polaris external setup. If one is found that has even a close curve, maybe be +/- a degree or two at the desired RPM points, than it would be a suitable replacement to keep our Fire series Deeres on the trail.

[AirborneX4Special]

Guys
Horicon Joe has been efforting a reman / repop project for the 82 and up ignition systems. It sounded like a very good shot at becoming a reality.

Pat

[ICCSF 108]

Todd, I'm not so sure the stator or flywheel would work on the Kawi engines if they came off of another brand. I also doubt if the older CDI (80-81 Deere or Kawi or Polaris ) will work with the 82-84 stators.. I believe that trying to make something other than using the OEM 82-84 CDI/Coils would be more like trying to recreate the wheel & probably more expensive..

Kenny

[Norton]

This has been a busy thread today. That is GOOD!

Kenny, my 82 LF came with an aftermarket CDI mounted in the normal location when I bought it 2 years ago. It ran in the low 80's until it got hot under the hood then it would only idle (rev limiter was disconnected). Cooled down again and it was off to the races. So I know an aftermarket CDI is or was out there. There were no markings on the one that was on my LF so I can not identify it except that it looked like a Polaris! I feel the way Todd does about discovering an CDI box only interchange,that will keep the 82-84 LF on the trails with the normal cost of a CDI.

The flywheel magnets are also a tuning factor. Where the North/South poles meet on the flywheel magnet is the point that triggers the pulse coil and signals the cap to drop its charge and fire the plug. Change the position of the magnet and you change timing. Course the flywheel has to fit the taper on the crank too. This is why a keeping it simple and just finding a interchangeable CDI box would be super, even if the timing curve would be off a degree or two. My sled salvage guy tells me the CDI Kokusan charge and pulse coils are the same even back to the first CDI's Kawasaki used on the 70's Cats. If true that would leave us those parts for years.

If Joe is working on a reman of the CDI for 82-84 LF, it would be nice to find out details. I hate give up on a great sled because of this.

Happy Easter to all,

keith

[nick80lf]

I’m not sure I agree with the statement that the charge and pulse coils are the same. Some time ago I was looking at a post about coil resistances for the Liquifires. The person that measured the coil resistance measured 82 coils. This resistance was different than what I found on both my 80’s. I then went to Kawaitrax and found a post there that had the same resistances I measured (within a few ohms). My opinion that’s not verified, the 82 to 84 coils probably had a few more wraps of magnet wire to produce a higher peak voltage output. I’m not saying older coils wouldn’t work. I just think the there would be less voltage (weaker spark).

On a side note, several years ago when in Sweden, I got involved with winding a coil for a position sensor. When we were doing this I was thinking why couldn’t you rewind stators. A bad one could be carefully dissected, count (estimate) the number of wraps, measure the magnet wire size, rewrap and coat.

I haven’t had one go belly up yet but when one does I thought I’d give it a try.

Nick

[JDT]

Kenny I was not thinking of changing any internals on the Kawwy engine, just the HSRI box itself.

I am sure that many of you have noted that the amount of spark differs greatly from one brand/type of sled to the next.
Some engines produce a very small spark and other snap like crazy but they both preform excellent.
I feel that what is important is not the amount of spark but rather that it occurs at the proper time.

I bet many of you have discovered a cornacopia of mismatched components on at least a few sleds that have entered our shops over the years.
Some have ran fine. Others, well now you discovered why they were acquired so cheap.

[That Girl Racing]

I am a little confused over this. You can always go back to the 80 style ignition system. They are plentiful and still look stock. I run MSD ignitions on my race stuff and believe me a "degree or two" is a hole in a piston. Also i have a 83 engine with a early ignition and I am absolutely sure that I did not change the flywheel or stator. (but I could be wrong). The easiest way would be to run a MSD or other aftermarket ignition that you can change the timing curve. Peter

[Norton]

Hello Peter,

I understand that the MSD ignition's run 800 to 1,200 dollars for sleds. That would be the top of the line system but for mine and others use, that would be outside the price range we would be willing to spend. When you say that 1 or 2 degrees can mean a hole in a piston, is that at WOT only on your race sleds or even at a midrange throttle setting? Timing that critical on stock motor with reg gas?

Wonder how many electrical and test engineers from the day with experience on this subject are reading these posts and having a really good time???? We are developing way more questions than answers "SO FAR".

Do you guys think Rainville is reading these posts and is now shopping for a MSD ignition for his Red Lake I-500 vintage race sled in 2011?? (-:

keith

[JDT]

From what I have read and seen Peter is on top of his game when it comes to making sleds break records. I would not be supprized if he has several thousand in some of his high performance tarmac eating drag engines.

But that is not the type of engine/performace we are dealing with on this thread. We are talking about stock engines that need to run on pump gas and do not require teardown hopefully more than once every couple of years.

Sure one can go out and spend a pile of money for go fast parts but my wallet would not allow that. I bet many others are in the same situation.

I feel that with a little more research a cost effective replacement can be found.

[That Girl Racing]

I realize that an MSD is not the answer but if the choice is between custom fitting a Fugi ignition which could be a technically demanding proposition or using the system out of an 80 Liquid or Invader I think it is a no brainer. Repopping the HSR is a cool idea but it is not like there is not a system that is readily available that will work. The HSR allows more initial timing because of its ability to dump timing over RPM. The timing is all out by 7000 RPM. If you think about it it takes a very short period of time to go from lets say 4000 to 7000. The early ignition did not have enough timing in it down low thus the dreaded bog. Most modern systems retard the ignition about 10 degrees. For example an 809 Skidoo starts at 25BTDC@4000RPM and finishes at 15BTDC at 8000RPM. The early ignitions ran a flat curve of lets say 15degreesBTDC. The 25 degrees of timing makes the motor very responsive. That was the benefit of the HSR ignition. If you bump the engagement up on an 80 ignition you go right past that bad spot. Peter

[JDT]

Peter how far of a bump on the 80 style ignition... 4500?

[That Girl Racing]

I run the early dual plug Kawi ignition which has " i think" is the same as the curve as the 80 Liquid. I engage mine at 6000RPM. Again, I don't think I changed the stator or flywheel but I should really look to make sure. Peter

[AirborneX4Special]

I had an 80 set up to engage at 5500 with a 108C, and it worked great.

[JDT]

I will try that when I get my 80 L-fire at that point. It is all stock now. Thanks