RZ350’s Gen II Mods, Part 19 - Auxiliary Grounding Harnesses

Link to all my Gen II mods

Even a great bike like the FJR can have its share of problems. A while back, I got involved in figuring out why a number or riders were having harness failures on their Gen II bikes. (See big discussion here Clicky). Although I own an ‘07A, I analyzed a spare 2008A harness I had lying around to put together this table.





The high amperage flowing through those small gauge wires proved to me (and some of the other folks) that there was a deficiency in the harness, especially at grounding connector or spider S4 (aka Black Widow). I decided to be proactive about this issue and plug-in supplemental grounding harnesses was the way to go since my bike was still under warranty. Some others have simply cut the grounding spiders out of the harness and soldered the wires together.

In the previously linked discussion, Road Runner and I came up with the idea (well, mostly Road Runner) of some simple T-Harnesses to take the high-amperage components (headlights and fans) out of the harness ground loop and pipe their current directly to a chassis ground. At the same time, they each provide a secondary ground path for many of the other components in the system. Here’s a sketch of the idea...



Road Runner has since offered T-harnesses to the forum members (Clicky) and I believe I was the first to receive a set. Installation was easy and the harnesses were well made. I believe it is adequate to eliminate the overloading situation. Brodie was also involved early on in the brainstorming, and is offering a complete grounding harness if you are looking for a more comprehensive solution and have a little extra time for the installation (Clicky). Thanks to both of these guys for offering an easy plug-n-play solution to the forum members.

If you choose to install something on your own, please let me caution you about tying the ECM or ABS ground spiders (S2 and S5) into the main chassis ground. Those two are fine as is and you may introduce some issues with feedback in those sensitive circuits if you connect them with the rest.

This use to be a major worry of mine after seeing the amperage numbers but to be honest, after installing the harnesses, I have completely put this out of my mind. Now that’s peace of mind! The only bad thing now is my Accessory Wiring Diagram is out of date - oh well.

Thanks for your excellent work on the spider issue. Did you ever have a spider failure on your 07? I'm asking because I'm sure I've heard of other 07 owners that had a problem, but when I checked the complaints filed with www.safercar.gov I only found my report. If we're gonna get this issue resolved by Yamaha, it's gonna require everyone with a problem to file a report!

Props on your charts-they became part of my service manual. I simply soldered 12 gauge wires to the top of #4 and#6 and ran them to a bolt on the steering head..

Harald said:

Thanks for your excellent work on the spider issue. Did you ever have a spider failure on your 07? I'm asking because I'm sure I've heard of other 07 owners that had a problem, but when I checked the complaints filed with www.safercar.gov I only found my report. If we're gonna get this issue resolved by Yamaha, it's gonna require everyone with a problem to file a report!

Click to expand...

Glad I could help some of you nice folks.

No problems with my spiders (that I know of!) - but it has low mileage. I agree, the owners that have had problems should be reporting it so we all benefit from a recall or something. I suspect there will be less and less failures, however, judging by the number of people being proactive buying Brodie's and Road Runner's harnesses. And there are plently of owners fixing it in other ways.

Just a followup... after 8 years (wow!!) with this simple harness upgrade added to my 2007, the bike is still running fine. No spider issues what-so-ever.

Thanks for the follow up. My 07 is still spider problem free and I didn't even install an aftermarket harness. My only mod is the elimination of the S7 spider that failed on my bike by cutting it off and soldering all the wires together.

I had the factory recall done when it came out, but before that I went through every spider and cleaned the connection and reassembled it with liberal amounts of dielectric grease forced into the connector and the cap. I haven't gone back to recheck any spiders since then.

I saw the recall letter years ago, but never acted on it because I had complete faith the problem was fixed, plus taking it to the dealer is a hassle. I never went around the bike and cleaned the ground spiders neither, but that would be a pretty good idea. Thanks for your comments.