Coil recommendation for '79 750 twin

Just spent the whole weekend getting the bike tuned up (timing, carb cleaning/syncing, plugs, brakes, etc). I was all ready for a ride and the first mile was great--easily 10 more hp than the bike had last year before I put it up for the winter. Then I got to the first stop sign, and the bike wanted to die off idle, just wasn't revving right, and ended up dying as soon as I pulled in the drive way.
It might be a fuel delivery issue (I'm running open pipe on stock jets), but I think the coil I pilfered from and old Honda finally gave up. Any sugestion for a replacement? A newer stock (Kawasaki/Honda/Yamaha/Suzuki twin?) coil would be nice, and probably cheaper, if I could find one used. Also, what kind of luck have you guys/gals had with aftermarket brands (Accel comes to mind)? Thanks in advance for your help...

Have you verified you have no spark at all?

An Accel 3-ohm or a Dyna 3-ohm coil is what you want.

I used a HD Screamin Eagle coil for a Sportster - the Orange coil. Go it pretty cheap ($45 new) from a local Harley shop - no shipping charge. Didn't fit in stock location, but that is no problem.

I like the Accel coils for the 750 twin, especially because they bolt right into the stock location.
And I think the yellow wires look cool

Others may differ.

loudhvx wrote:

...or a Dyna 3-ohm coil is what you want.

That's what I got and it might have been the best change I made to the bike(s). Bolts in the stock mounts, with nice, replaceable wires...

Yeah, I've priced the Accel coil, but it's about $100. Youch! But I've heard the same thing about a good coil--it makes all the difference.
In answer to the question, I do have spark, as I've timed it, it starts, idles cleanly, etc. About one block into my test ride though, the bike just did not want to rev, and it was all I could do to keep it running until I could make it back to the driveway. I messed with the float adjustment when I had the carbs apart (back to "flat") so it may be the bike is running out of gas just enough to make it sputter. Either way though, I will get the coil, especially after I fix the starter (no fun kicking an old bike in 90 degree weather). Another question about the H-D coil though--will it work on a bike with no electronic ignition? I thought resistance for coils on bikes thus equipped were WELL below 1 ohm, at least nowhere close to the 3 required for my rusty beast. I certainly like the price you paid, though...

The Accel single coil setup is available for ~$67 plus shipping from Maw and other places, and the KZ's with electronic ignition work fine with the 3 ohm coil, as do the points models. I have converted a couple of KZ750 twins to electronic ignition, and the three in my sig will be converted using the Accel 3 ohm coils.

I'm sure the Dyna is just as good.

Well, it turned out to be a fuel delivery issue, after all. As I pulled the tank off to clean the fuel valve again, I noticed it felt awfully light...after I tuned the bike initially, I added only enough gas to let it run for a minute or two as I was timing it and sync'ing the carbs. Afterwards, as a result, it ran fine as long as it was on the kickstand, leaning to the left, but as soon as I stood it up to ride it, sputter, sputter, sputter. My bike buddies, and my wife, and my father in law, got a pretty good laugh out of it--none of them thought to even ask me if it had gas in the tank--so I'm sure you guys will too. I'm a jackass.
Thanks for all the good coil advice though--I'll probably go with the Accel, because those yellow wires DO look pretty freakin' cool.

You'd be surprised how many times people have asked me to troubleshoot their carbs or electrical problems, when all I had to do was add gas.

One guy had this happen twice in a week. Man did he take a lot of ribbing! :lol:

RustyB4 wrote:

Another question about the H-D coil though--will it work on a bike with no electronic ignition? I thought resistance for coils on bikes thus equipped were WELL below 1 ohm, at least nowhere close to the 3 required for my rusty beast. I certainly like the price you paid, though...

The HD coil measured ~2.8 - 3.0 ohms, The HD tech I talked to said it was for their electronic ignition equiped bikes, and the points version was 4.5 - 5.0 ohms. I have it on my twin with points ignition right now, and it works great. MUCH smoother. I have an electronic pickup from a 440 LTD that I am going to put on, with a Mallory HyFire VI-aL. Anyone know for sure if I need the ingiter from the LTD, or can I just use the parts from under the points cover to trigger the Mallory unit (I need to find the manual)?

Oh yeah, I've had the no fuel issue that I could have sworn was an ignition problem too (It really IS an ignition problem, NO FUEL to IGNITE!!!).

I really need to get a new speedo cable, I can never remember when I last put gas in the tank!!! and I just have too much fun riding to be bothered trying to figure out how far I've gone!

Post edited by: securitygeek, at: 2006/08/14 17:17

If you have the 440 pickup then you need either the 440 or the 82-83 750 twin timing advancer. There are other options but using the points timing advancer is not one of them. You need the igniter as well, but you can use one off a four cylinder by just using one side of it.

I have no idea what will work with the Mallory, I don't know if you need the igniter or not.

Post edited by: steell, at: 2006/08/14 18:19