coil mod success!

Put on WG's coil mod this morning, and what a difference!! Idle is more stable, and it is running a whole lot smoother! Took it out and wound it up for a while, and the difference is simply amazing. Still seems it wants to die sometimes at ilde, mostly after it gets good and hot. From what I have read here, that might be valve clearance - I need to check that when I get a gasket.

Thanks WG!! :woohoo:

Cool Man! Good job... don't it feel good

Great news.

I also did the mod last Winter and my bike has been running great all season.

Gonna do this too it realy helps eh,
did you guys get part from napa?
after my rejetting quest is over.

Gonna do this too it realy helps eh,
did you guys get part from napa?
after my rejetting quest is over.

What is the WG coil mods and can it be done on a 78 KZ1000?

www.wgcarbs.com/59021.html

What is the WG coil mods and can it be done on a 78 KZ1000?

It powers the coils direct from the battery, bypassing the aging stock system. WG's instructions were written for a four (mine is a twin), so I would say it should work as written. The write-up talks of a two-into-one connector, that mine does not have (one coil on a twin). Other than that, it goes down as described.

I got the parts (relay, wire, shrink wrap, etc) at the local Advance parts shop. The relay was with the fog lights - about $4, rated for 30A. There was another one in the electrical section, rated for 20A, for about $6. Go figure. Under $20 total parts. No pigtail though, I just soldered direct to the relay lugs and put shrink-wrap over 'em. That will suck big if the relay goes south!

Biggest problem I had was soldering 12g wire to those lugs with a 25w iron. THAT was painful.

EsaPro wrote:

...Still seems it wants to die sometimes at ilde, mostly after it gets good and hot. From what I have read here, that might be valve clearance - I need to check that when I get a gasket....

Two things:

Yep, it could be valve clearance, it could be a bad coil. The coils on both my 750s were bad, one more than the other. But, both got worse when warmer. I had the same exact symptoms you have experienced, and the coil mod did wonders, then the replacement Dyna coils finally made the bike run like it was new off the showroom floor.

Regarding valve clearance and a gasket: I ended up not needing a new gasket when I did my valves. I guess I got lucky, but it came apart perfectly and went back together no prob. Here's a tip: when re-assebling your top cover after the valve work, remember to slacken your cam chain via the tensioner BEFORE tightenting the bolts to torque spec. Then, after they're all tightented down, re-adjust the tensioner...

Biquetoast... Question regaring your comments about coils that performed worse when they warmed up... Did you measure primary and secondary impedence on these coils? If they performed worse, seems that the resistance was going up when they heated. I hope Loudhvx or somebody could jump in and comment on why resistance went up when the coils warmed... seems that is what would degrade their performance. If this happens on a twin, it would happen on any coil and it is worth chatting about and coming up with some ideas why. Thanks!

As far as WHERE to buy supplies when doing the coil mod... depends on what parts you are talking about. The NAPA in Castroville has a GREAT selection of lighter gauge auto wire in a BUNCH of colors. As far as shrink wrap and connectors, I buy these in bulk from Harbor Freight in San Antonio. They sell shrink wrap kits where the wrap is precut and in a small parts box. Really is handy and the pieces are suited decently for most bike applications... there is always a lot of the larger pieces still unused but still a good buy. They also sell big "kits" of crimp on connectors and it is cheaper to buy these kits than buy individual packs at Walmart. Walmart also doesn't have a good stock of the red (very light gauge) wire connectors. As far as relays and pigtails, I buy these in quantity from a local San Antonio car alarm/window tint/stereo install shop. They are glad to sell them to me and will sell them about a dozen sets at a time for a couple bucks a set (relay/pigtail). You can also get a single relay/pigtail at many of the places that sell truck light bars...

Post edited by: wiredgeorge, at: 2006/10/09 08:55

wiredgeorge wrote:

Biquetoast... Question regaring your comments about coils that performed worse when they warmed up... Did you measure primary and secondary impedence on these coils?

George I'd love to tell you I did, but I have to admit I'm completely ignorant about the electrical stuff and it compleely confuses me... so, no. I had replaced nearly every other wire,connection and part on the bike and the coil was the only thing left. :blush:

Also, I didn't want to mention this until I received the parts but it looks like a good time:

I found a supplier for these "coil mod" parts just yesterday and placed an order. They are called PartsExpress.com. I am awaiting shipment, so I cannot comment on the complete transaction, but I am stunned at how cheap they are. Here's a sample:

Bosch Relay
Waterproof Relay
Pigtail
Wired Fuse Holder

Wow! Great find... that will save trips to town as the prices are very competitive even with shipping.