Triumph Bonneville T100 Starting Issue - Infamous Clicking

It's been a few years since I have dealt with this issue but I wanted to keep this post for future reference in case the post on Triumph Rat Forums gets taken down/deleted.

This is one proposed solution to the issue with Triumph Bonneville ECUs. Apparently the ECU does not like batteries with slightly low power. Before implementing this solution I would be going through batteries almost every season. Here is a video showing the problem on my bike.

Here is a copy of the post with pics:

"Hi all,

Sorry for reviving an old thread but I came back here looking for the thread to redirect someone else to it only to find the original photos gone (thanks Photo£uckit!). Well, I happened to save all of these down for my own mods journal back when I made this mod to my own bike. Hopefully the originator does not mind me reposting his great info with edited text of his explanation of the mod. All pasted below, none of my work, but I confirm that it works 100%.

>>>>SNIP WITH TEXT EDITS<<<<

1 by Andy G, on Flickr


The*clutch*switch*grounds the BLACK/ORANGE, I tapped it to supply ground for the*Starter*Relay. Begin by exposing the BLACK/ORANGE at the ECU. It's located in the 'B' connector, right side of the ECU. Here you can see the wire exposed, it's the fourth pin on the front row:

2 by Andy G, on Flickr

Clip it, here is where you add the diode (any 1A rectifier will do), which prevents stray voltage form the*starter*relay*coil being back-fed into the ECU. Observe polarity, the band goes toward the*starter*relay.

3 by Andy G, on Flickr


You may have by now snaked your new wire run into the*ECU*harness*in preparation for your final connection at the plug. Twist it together with the other side of the BLACK/ORANGE. I used a yellow wire because I had lots of it.

4 by Andy G, on Flickr

5 by Andy G, on Flickr

Close it up, tape the boot back on as you found it. The other end of the wire goes to the*starter*relay, cutting into the YELLOW/BROWN as shown on the diagram.
The result of this mod requires you to pull the clutch in to start AND bypasses the ECU signal to the*starter relay.

>>>END<<<<

Hopefully someone finds this useful.