Budget total loss?

[Waternut]

Is it possible?

Here's my thought...By just removing the magnets on the stock flywheel, you'd lose quite a bit of weight for no $$$ out of pocket. Can the stock ignition be modified to run without the magnets? If so what is necessary? Is it as simple as getting new coils or is there a conversion that would have to be done as well?

I know the 04+ SXR's can run without the magnets but I believe the 750's and 03 and earlier SXR's needed the magnet/stator to get a spark on the plugs.

I also know I'd lose the ability to fine turn the timing but for the price, I think that's one thing that I could do without since I'm without it already.

 

[Matt_E]

For Yamahas, the answer is no, absolutely not.

For Kawis, I guess you can (as you indicated), but I would not do it as the benefits will not be nearly worth it.
The benefits of a true Total Loss ignition come from primarily four factors:
1. Lightweight flywheel - taking magnets out of a stocker will not reduce it to TL FW weight
2. No electromagnetic drag
3. Programmability of the ignition, custom curves
4. More spark power, same spark energy throughout the RPM range


What you propose - and what others have done successfully - simply reduces flywheel weight a tad and looses some EM drag.

 

[cambo au]

i aint sure if the ignition can be modified to work with no magnets i doubt it but if it could i agree with you as far as a cheap tl system you would not have any programability and the spark would only be like stock but it would give you some cheap low end grunt

 

[Kaveman]

The magnets send a pulse to the charge coil, the charge coil sends power to the CDI and wakes it up. The pulser coil sends the signal to the CDI telling it when to fire. Without the magnets it will never fire, unless you install a two position (open/closed) switch sending power to the brown wire with a white tracer. You would also need to verify how much voltage comes out of the charge coil and if necessary limit or amplify the voltage going to the CDI in order to get proper performance and protect the CDI from damage. Yamaha has peak voltage specs for all of the coils in the electrical system.

I suppose that it could be done but not with the results you are hoping for. I would recommend against it.

 

[Watty]

A budget total loss system is an analog one that you pay under $100 for...problem solved.

 

[Mark44]

p

A budget total loss system is an analog one that you pay under $100 for...problem solved.

Then the budget problems start, hope you are handy with a multimeter.

Mark44

 

[Kaveman]

I checked in the service manual and the charge coil puts out 22.3 DCV at open cranking speed, 21.0 DCV at regular cranking speed, 46.4 DCV at 2000 RPM and 65.2 DCV at 3500 RPM. This is unregulated voltage going directly to the CDI. These specs were on a non power valve 1200 but are very similar for the twin electrical system.

 

[Mouthfulloflake]

are you sure the CDI gets DC voltage?

 

[#ZERO]

Yeah... I always thought the magnets would crate an AC voltage to the CDI? :scratchchin:

 

[Watty]

Then the budget problems start, hope you are handy with a multimeter.

Mark44

Yeah, if you are a hack and have no clue what you are doing, you will have problems. The same goes for jetski's...if you don't know what you are doing, the engine eill blow up. If you don't know how to drive your car, you'll crash it...so on and so forth.

 

[Waternut]

So I guess there are a couple options to further increase my low end then...

1. Get the stock flywheel lightened by GroupK for about $100.
2. Get a charging flywheel for $400-$500...ouch!
3. Get a digital total loss and flywheel...even more $$$.
4. Get an analog total loss. Even they look like $250-$350 and I don't know anything about them other than many people don't like them.

I know you've gotta pay to play but geez...

 

[Mouthfulloflake]

other ways, some are cheap ways:

make sure your jetting is at least close to dialed in

lighten the flywheel

advance the timing

bore the pump nozzle

Add compression

 

[Waternut]

other ways, some are cheap ways:

make sure your jetting is at least close to dialed in

lighten the flywheel

advance the timing

bore the pump nozzle

Add compression

-I'm working on the jetting now (may have it professionally done if I find someone qualified).
-Nozzle is bored already.
-Freestyle pump cone has been ordered.
-I have a swirl prop that I'm holding off on installing (until spring) in order to see how much difference it really makes.
-Compression has been added by milling the stock head but I'll need an engine rebuild soon. The head is supposed to deliver 180-185psi and I'm at 155-160.
-I'm trying to figure out if I've got a timing advance already but can't find installation instructions anywhere to figure it out. The ski had a lot done when I bought it and I want to confirm it before ordering a new one.
-The flywheel issue was why this post was started.

 

[Mouthfulloflake]

its a 750sx?

Its been a long time since I put an ignition advance into one those stator covers, but is it not possible to tell by looking?

I dont recall what the stock mounting plate looked like, maybe they are hard to tell unless side by side.

 

[crammit442]

-I'm working on the jetting now (may have it professionally done if I find someone qualified).
-Nozzle is bored already.
-Freestyle pump cone has been ordered.
-I have a swirl prop that I'm holding off on installing (until spring) in order to see how much difference it really makes.
-Compression has been added by milling the stock head but I'll need an engine rebuild soon. The head is supposed to deliver 180-185psi and I'm at 155-160.
-I'm trying to figure out if I've got a timing advance already but can't find installation instructions anywhere to figure it out. The ski had a lot done when I bought it and I want to confirm it before ordering a new one.
-The flywheel issue was why this post was started.

If you have the timing advance plate you'll be able to see it when you take off the flywheel cover. The pickup will be mounted to a small aluminum plate instead of directly so that it's offset in the advanced direction. A lot of times you will see that you have a thicker green flywheel cover gasket also to account for the thickness of the advance plate. Sometimes it's necessary to grind a bit on the pickup or cover for clearance. This is what it looks like.

 

[Mouthfulloflake]

thats what I was thinking, but I couldnt remember if stock was a plate or to the cover, I remember grinding the stator cover itself instead of my pickup when I installed one back in 1863

 

[Waternut]

If you have the timing advance plate you'll be able to see it when you take off the flywheel cover. The pickup will be mounted to a small aluminum plate instead of directly so that it's offset in the advanced direction. A lot of times you will see that you have a thicker green flywheel cover gasket also to account for the thickness of the advance plate. Sometimes it's necessary to grind a bit on the pickup or cover for clearance.

Thanks for the good description. Well I tried to go out to my ski and look but it'll take me an hour to pull the pipe off again and look under the cover to see. I just want to confirm...It would be under this correct?

 

[D-Roc]

i have an advent ignition for your sxi/sxr that you could put on that has 4 curves and will allow you to run it without the magnets or stator. i have a stock flywheel with magnets removed also. make me a reasonable offer and it is yours.

 

[Speedfreak]

Yes the advance plate bolts to the stock pickup screw holes and moves the pickup closer to the cover on the left side of your picture

 

[Matt_E]

Yeah... I always thought the magnets would crate an AC voltage to the CDI? :scratchchin:

AC from the stator (obviously).
Rectifier, well, rectifies it.