Dyna CDI and Engine miss

[Hunterworks]

We have had a couple guys who have had an engine miss with the non-programmable cdi and curve 2 on the programmable one.

I have two here that were missing and I tested them on our Teryx with no problems.

It seems that any Teryx that is right near being too lean from the factory are the ones having the trouble.

Heres the deal. To achieve top performance you need the peak power point to be at 15 degrees after top dead center. Kawasaki severely de-tunes these engines with timing leaving a good bit of room for performance gains with just timing. With stock timing the peak pressure point is occurring after this point which hurts performance. They do this for reliability.

Now we advance the timing which fires the spark plug sooner than stock and allows more time for the fuel mixture to burn and allows the peak pressure point to be close to the optimal point of 15 degree after top dead center for maximum push against the piston.

So you take a engine that is border line lean and advance the timing and allow the fuel to burn longer you will run out of fuel to burn thus causing a lean condition.

Guys are reporting switching to curve 1 and the problem goes away and it is because there is not as much advance but they are losing some potential performance by doing this. The answer should be add more fuel with a needle position change and/or larger main jet.

I know this is going to sound like a selling point but the carb kit we sell will fix this problem for you and add some performance at the same time.

Now to toot our own horn here. Take these two guys who sent their CDI's back for us to test. What if we were like most other places and just sent them some replacements and they still got the same problem because the problem was not the CDI. The same guys would call back and still not get an answer then just ask for their money back. Everyone would be frustrated and there would still be four perfectly good CDI's that could not be sold as new and nobody would know why. These two guys would go out and just say the Dynatek CDI is not good and all the while it was their jetting.


We ran our Teryx on our dyno with these two CDI's with the load control on really hard which made the vehicle work really hard. We will also send these back with no return shipping even though there is nothing wrong with them.

Whether you buy these items from Hunterworks or not, make sure where you do buy it from can fully support it and don't just look at the price. Good service cost!!

Todd

[dieselpowered]

Excellent information my friend, thank you for sharing!

[djkelsoe]

Todd,

I am one of those that is extremely happy with my cdi but thought that it might have to be re-jetted. From what you posted, I gather we need to either re-jet for optimium performance on curve 1 or 2. The re-jettng may be in ordering bigger jets or your carb kit. Is this what you are saying,or am I mis-understanding?

On a side note, I understand that this is a science project and the learning curve is a little steep when trying to decipher all the variables. I am also trying to do the same thing so honesty is a great learning tool which we can all grow.

[Hunterworks]

Simply my curve which is the stock curve if you bought it from us or curve two or even the non-programmable would be the most power. The problem is some people have a miss when using these curves due to a lean condition after the install.

Those persons need to richen it up in the RPM range they are having problems.

1/4 to 3/4 throttle they need to raise the needles, 3/4 to wide open they need a bigger main jet. But if you are having the problem at mid to wide open then change to a larger main jet first before you try adjusting your needles because when you change main jets you change the way fuel is metered from 1/4 throttle up. You always set a carb up from wide open operation with the mains backwards.

Since the stock needles are not adjustable you would need some needle shims or a carb kit which has replacement needles that are adjustable.

Now I have a jaded opinion but if you bought our carb/intake kit this would solve your problem.

On the other hand if you are not having this problem the kit does great as a performance enhancement and everyone who has given me feedback has said it has been the best performance mod they did outside the CDI itself.

[Jaybo700R]

Todd, You are a huge asset to the community here, Thank you for all of your testing and work, your pride in what you do shows through in every post. Thank you.

..Jay

[T-REX]

This sounds like the same problems I was having running lean.

I did send my CDI back to Dynatec for warranty two weeks ago.

So it is likely that I will get the same one back or even another one and still have the same problem.

It looks like I'm going to be getting your kit, now my next question can I still install the air box kit and CDI and solve these problem and still run my stock exhaust?
I just don't want to spend 700+ dollars for a system

thanks for the number I did call but I was to late and they closed I will have to try again Next week.

Thanks for all the hardwork with the dyno test to help solve these problems.

[Hunterworks]

Jaybo,

Thanks for the comments, our motto is "We don't suck"

T-Rex

No need for the aftermarket exhaust but our future testing will show what works and what does not on exhaust. Our kit now comes with some larger main jets for future jetting needs on aftermarket exhaust.

[T-REX]

they finally sent back a new cdi and this one works great.

[Hunterworks]

Yours might actually been bad.

Todd

[T-REX]

yeah I called Dyna and they said it was shorted inside.

what ever that means I have never seen inside one.