Anyone familiar with this Yamaha XS650 CDI Magneto?

Reminds me of the cdi that came out in the early 70's.......gave the MX's noticeably more zip due to less flywheel weight as compared to the larger flywheel.........the problem for the street we found (besides no coils for lighting) was running ratty due to way less flywheel weight that dampens the pulses.....was a racing option only to the street engine gurus.........xsjohn

Did try one on my RT1 street bike that I rode for years in Fl in the seventies......after 10 minutes I was back to the flywheel.........I even found some diesel cylinder that fit over the flywheel and cut a couple inches and pressed it over the large flywheel to give it more dampening .........ran slick as a baby's ass then.............still have them both......
 

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(this is the answre that i got when i ask about the unit)

I'm returning your email request for info about the magneto's I'm building.

They have been very relible. There oem unit's on some chinese manufactures models motorcycle's. I've sold kits for the xs and Honda 160/175s totaling 35 units and have had one problem where the buyer didn't have the unit or kill switch grounded properly and as soon as we diagnosed the problem that corrected that. I'm also in the process of adapting the unit to Smaller Yamaha twins and TT/SR500, BSA and Triumphs and Xl 250/350 models and 180 crank applications.

The ARD units are out of business, costly and hard to time correctly, (No keyway on there rotors)and there's very little support for them now. The PVLs are a great unit, they do electronicly advance (Mine Don't)and come most compleate. There $600.00. Mine are around $320.00 complete with coil, kill switch and instructions. I offer a back-up unit for $40.00. Some like to have a spare at the track just incase. There very simple to install, just follow the instructions and your going to be timed right around 35*degrees BTD and probably about an hour your ready to go. There's plenty of adjustment for that Dyno run to maximize your timing without romoving the rotor and starting over. The units do not electronicly advance so I've set them at the stock full advance setting. I've had no problems with this besides the bike being cold blooded tell warmed up. I start my bikes with rollers and have had no problems. If you where starting them with a kick starter? You may have problems running full advance.

One other little thing; ARD is NOT out of business. You have to know who to call if you need parts. If you want a new unit (ARD) you will wait a vary, vary log time,( read infinitely) and should seriously consider an alternative ignition ;PVL or MZ-B or MOTOPLAT or Mike Riddles unit.
if you have an ARD, and need parts, they are available, again you will wait awhile to get said parts
ARDs are not hard to time; I have never had an issue timing my ARDs,; never had one move after being timed. And have never had one fail. And I have run a few of them vary long and vary hard.
With that said; I think the ignition Mike is building is vary good for us XS ers . I don’t run batteries in my XSs, its just more weight in an already heavy package. If wanna go for an all day ride ,I’ll ride one of my Triumphs or a Harley. I run ARDs in my Champion XS street trackers w/ a vary small total loss battery ((brake light). But that’s the way (I) like it.
BTW- I am working on a CDI/MAGNITO with charging capabilities that is vary similar to the ARD/PVL units. Vary small, vary light, with a vary bright blue spark. Yes they will be expensive ; but for some of us , only the best will do.
 
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The more flywheel weight...(or crank weight for that matter)...the smoother the engine is going to run.....less ratcheting .......rather than increasing my flywheel weight I chose to run it a t 8-1 to make it run very smooth....since I knew how to do it it cost me nothing...and like I have said many times these are timed up for all the revs.....with a .168 thousands retard on the TCI it runs like a toyota now.....and flywheel ignitions are very accurate.........sorry for the teck rant......back to chopping .......:wink2:

think this is right.....don't have all the manuals.....internet search........?
70-76 8.7-1
77-79 8.4-1
80-84 8.7-1

xsjohn
 
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Its cold outside, that’s the reason Im on the pc; getting old I guess;
In any event I totally understand what you’re saying. I (and everyone else that has the capacity to do so) have built cranks using heavy metal(Mallory) spell check; and 4140 tubing machined at an interference fit, pressed over the flywheel(s) tig welded in place, all in an effort to control the (hit) of a race motor. All with some varying degree of success. I guess the bottom line is that I don’t race anymore; alittle street racing when confronted with THAT BADASS HARLEY THAT EVERYONE HAS (ME INCLUDED). Even at my age I just can not resist the look of (I can’t believe that fucking Yamaha beat me to the light) Priceless….. at any rate, today I build my XS motors with that (HIT) on tap, just for such moments. These(XS) motors have potential, you just cant half ass build one and expect it to last or run proper. Then again, I don’t believe I am saying anything you and others on this forum don’t already know.
Back to the ignition. I cant believe that people throw money at the stock ignition on an XS when it fails; to many options out there.
>maxx40x.
 
Maybe not to the light but in miles I am heading for the 4th time around the world....76K on this one.........stock 80 ignition ...stock pistons too....what would I know..:bike:

xsjohn
 
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