DYI Total loss or MSD TL upgrade box 270USD?

Joined
Jun 13, 2018
Likes
0
Location
Boston
so the 64x triggers off the lumps and the others are triggered by the magnets and their position in relation to tdc?
Does anyone know if this is the same arrangement as a Kawi 650 flywheel? There are 4 magnets, I don't believe there are any "lumps". Is it just charging based on all 4 magnets and the CDI gets 2 firing pulses from 2 opposing magnets?

What kind of sensor/signal is this lump/pickup in a 760? I would like to remove the magnets from a Kawi 650 flywheel, add whatever "lumps" need to be added, and then have it machined and re-balanced.

And yes, its an absurd amount of work for a Kawi 650, but I have my reasons.
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
I know you can put 650 electronics on a 750. Can you put the 750 flywheel and stator on a 650? The 760 and 750 flywheels work the same way and look very similar.
650 flywheel is preferred in terms of weight. The 750 electronics are more modern but the flywheel is bigger/heavier. Holy grail would be a fully programmable modern CDI based on a lightweight 650 flywheel. It wouldn't be quite billet, but I'm pretty sure that a 650 flywheel with no magnets and lightened/balanced by newmiller would be a killer gain by itself, nevermind the ability to set a proper curve.

I'm guessing the 760 lumps are just ferrous metal and the pickup is an inductive sensor? Shouldn't be too hard to replicate
 

beerdart

4-Tec Jetmate
Joined
Sep 8, 2006
Likes
23
Location
CT
650 flywheel is preferred in terms of weight. The 750 electronics are more modern but the flywheel is bigger/heavier. Holy grail would be a fully programmable modern CDI based on a lightweight 650 flywheel. It wouldn't be quite billet, but I'm pretty sure that a 650 flywheel with no magnets and lightened/balanced by newmiller would be a killer gain by itself, nevermind the ability to set a proper curve.

I'm guessing the 760 lumps are just ferrous metal and the pickup is an inductive sensor? Shouldn't be too hard to replicate
Correct the pickup is inductive and the lumps are on the outside of the flywheel should be easy to adapt to the 650.
 
Joined
Jul 17, 2010
Likes
1,219
Location
Chesapeake, VA
650 flywheel is preferred in terms of weight. The 750 electronics are more modern but the flywheel is bigger/heavier. Holy grail would be a fully programmable modern CDI based on a lightweight 650 flywheel. It wouldn't be quite billet, but I'm pretty sure that a 650 flywheel with no magnets and lightened/balanced by newmiller would be a killer gain by itself, nevermind the ability to set a proper curve.

I'm guessing the 760 lumps are just ferrous metal and the pickup is an inductive sensor? Shouldn't be too hard to replicate
You know I lighten these flywheels all the time, right? I’ve seen some questionable stuff lately that was claimed to be done by new Miller...
And actually, a 750 with no magnets and lightened would be lighter than a 650 with no magnets because of where the load is on them and thus how much metal you can remove. Not to mention saving time and money trying to reinvent the pickups....
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
You know I lighten these flywheels all the time, right? I’ve seen some questionable stuff lately that was claimed to be done by new Miller...
And actually, a 750 with no magnets and lightened would be lighter than a 650 with no magnets because of where the load is on them and thus how much metal you can remove. Not to mention saving time and money trying to reinvent the pickups....
I did not know that, hope it didn't come off as insulting. I'm rarely on these forums so not always up to date. Interesting though about the 750 potential, to be fair it doesn't even need to be "lighter" if most of the mass is removed from the outside versus inside, makes total sense if you are comfortable removing more material from the perimeter.

I thought there was something different about the tapers between 650, 750 sp and 750 bp. Is it all 750 flywheels that have the lumps already there? I was under the impression only late model SXR had this style of ignition/pickup. Do you know how interchangeable 750/650 flywheels are?
 
Joined
Jul 17, 2010
Likes
1,219
Location
Chesapeake, VA
All the 750s have the two lumps. I do not know off hand if they are the correct length. I would guess they are very close, if not the same, as the 760.
And if my kawi knowledge is correct, I believe you can only use the small pin 750 flywheel on a 650 crank. That’s the one with the larger taper for clearance on the back side.
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
All the 750s have the two lumps. I do not know off hand if they are the correct length. I would guess they are very close, if not the same, as the 760.
And if my kawi knowledge is correct, I believe you can only use the small pin 750 flywheel on a 650 crank. That’s the one with the larger taper for clearance on the back side.
Did some reading, and it appears the early small pins should be a direct swap, but later small pins are same taper/setup as a big pin. This sort of brings me back to wanting to just run a 650 flywheel as they are abundant and I know they are a drop in. Unless its a simple modification to drop a big pin flywheel on a 650.

If the lobe is just a piece of metal, it should be easy to weld a couple of "lobes" inside a 650 flywheel and mount a pickup to a gutted stator plate.

I am curious about the idea that a 750 flywheel can become lighter/have less rotational inertia than a 650 flywheel though.
 
Joined
Jul 17, 2010
Likes
1,219
Location
Chesapeake, VA
The sides of the 750 don’t need to carry load of starter via ring gear to the crank, so I can make them thinner. The ring rear is also smaller on the 750, I think, so it would weigh less. It’s easy to identify the 750 flywheel you need visually. And again, how accurate is your welding going to be? Think you need to go back to checking if you can bolt the 750 stator to the 650... You’re over complicating something that’s already done.
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
The sides of the 750 don’t need to carry load of starter via ring gear to the crank, so I can make them thinner. The ring rear is also smaller on the 750, I think, so it would weigh less. It’s easy to identify the 750 flywheel you need visually. And again, how accurate is your welding going to be? Think you need to go back to checking if you can bolt the 750 stator to the 650... You’re over complicating something that’s already done.
Well I can't really argue the 650 vs 750 weight, but I can certainly say that its alot easier/cheaper to use 650 parts than 750 parts, and given what I'm trying to do, that has value to me.

I could be missing something, but can't you account for any "welding inaccuracy" with a dial indicator and the static angle offset of the CDI? I suppose if you didnt get the two lobes at exactly 180 apart that would be an issue. But this is where "measure twice cut once" comes into play. Or better yet, I think I have access to a water jet so might be easier to just get a trigger wheel made up and weld that inside the flywheel to be sure that the lobes are perfect. Either way, I think its a solveable problem.

Aren't the pickups for 750's mounted on the covers? I wouldn't need the stator as I'm going for total loss here. Off hand I want to say you can swap covers between them, so yes, the correct small pin flywheel lightened + cover and pickup would be the optimal solution. Just curious how much work it would really be to cook something up thats based on the 650 and doesn't require hunting down the perfect flywheel.
 
Joined
Feb 26, 2017
Likes
193
Location
Minnesota
I'm a little curious what you're doing. Might be worth looking at a complete 750 case for bigger reeds maybe? Unless you are in some sort of racing class that requires using a complete 650, or just happen to have a bunch of 650 stuff you want to use up and you like to tinker?
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
Shouldn’t be a hunt. 750 flywheels are everywhere. Easier to check eBay than fabricate lobes and plates and brackets and such like you’re talking about...
I thought about it on my ride home and you are definitely right. All things considered it makes way more sense to find a SP flywheel and cover and just bolt that on.

How much do you charge for lightening/balancing on a 750 flywheel if I send it to you with the magnets already removed?

I'm a little curious what you're doing. Might be worth looking at a complete 750 case for bigger reeds maybe? Unless you are in some sort of racing class that requires using a complete 650, or just happen to have a bunch of 650 stuff you want to use up and you like to tinker?
I am setting up a bench dyno of sorts. Pump and all. I want to get a hands on education regarding 2t tuning/porting and I expect to ruin some parts along the way. I'd rather do it with 650 where parts are cheap/plentiful rather than 750/701. Plus I have alot of 650 stuff on hand already.

I'll be running my setups in a surf oriented X2 as well.
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
Hopefully this hasn't already been covered, but I'm pretty sure that PDCIS-11T can be used as a ECWI controller as well. You do not need to run the TPS but its there if you want it. Power jet 1 output is on off, power jet 2 output is a solenoid duty cycle output. Worst cast is the driver in his CDI can't handle a water solenoid, which could be solved with a solid state relay pretty easily. Has anyone tried this?
 

waxhead

wannabe backflipper
Joined
Jan 15, 2006
Likes
895
Location
gold coast
I was using a zeel tronic with a relay to turn on the fuel pump in my bs3 belassi I put a gp1200 into. I was also turning on a bilge pump with it when the engine went over 1000 rpm.
 
Joined
Jun 13, 2018
Likes
0
Location
Boston
I was using a zeel tronic with a relay to turn on the fuel pump in my bs3 belassi I put a gp1200 into. I was also turning on a bilge pump with it when the engine went over 1000 rpm.
Good to know, I think I am going to try and work with the PDCIS-11T and run ECWI. I don't think TPS 3D mapping is worth the effort though. Any experienced engine builders/tuners please chime in. My understanding is the PWC load is pretty much on or off.
 
Top Bottom