Upgrade to NTX starter circuit

[pyoungbl]

Every modern motorcycle I have owned came with wiring that was too small, particularly the connection from battery to ground and battery to starter. Upgrading these two wires helps the starter spin the engine faster, leading to quicker starts. In addition, the Stelvio ground connection is a 26" long wire that attaches to a 6mm bolt which is doing double duty as a stud to secure the starter cover.

The easy part of this upgrade is getting the correct wiring from http://www.motolectric.com. Michael Heath made up the wires to my specs. I believe he is using welding cable. It's very flexible and easy to work with.

The new ground wire is both thicker and shorter than OEM.

Here you can see where the ground lead comes down from the battery and attaches to a bolt located below the starter...the starter is removed for this photo but you get the idea.
I moved the engine ground from under the starter to the right side of the engine, where the transmission bolts to the block.

For the + cable it's a bit more interesting. It is best to remove the starter from the bike, just two 13mm bolts, but it's a tight fit due to the starter wires being so close to the frame.

I had planned to route the starter wire so it came to the starter from below where I thought I'd have more clearance from the frame. That did not work well because the change put the wire in the way of the shift linkage. Another good idea goes in the trash can! The OEM harness has the starter wire crimped to the battery terminal along with a bunch of other wires. The best solution is to cut the starter wire close to that terminal and then insulate the exposed lead.

The new + wire is then routed from the starter up to the battery. It took a couple tries to get the starter connection so it was well clear of the frame but the end result worked well. I had asked Michael to lengthen the + lead but in hindsight it could be about 2" shorter than what I ordered.

This looks like a tighter fit than it actually is. I think I have about 1/4" clearance between the crash bar and the starter lug, still pretty close but nothing rubbing.

While doing this upgrade I also moved another ground lead from above the starter to one of the starter bolts.

This is an easy improvement and should provide a much better ground path. All I had to do was move the wire, no cutting/splicing involved.

Did I notice a huge change? Nope. The bike seems to start a bit quicker. We all know how a loose ground can cause a multitude of problems with these bikes and I expect to avoid that gremlin.

 

[Brian UK]

Worth doing the mod detailed in the startus interruptus thread too.

 

[WayneOrwig]

Are you fixing something here?

This will raise the starter peak inrush currents, putting more stress on the battery. I have had Guzzi starters pop welds inside the battery, so I don't want to stress the battery more.

 

[pyoungbl]

Wayne, I'm fixing a few problems all at once. The OEM positive lead from battery to starter was chafing on the crash bar bracket. This had already eaten through the protective boot at the starter stud. The problem was noted in a recent notice to dealers. Next, the ground below the starter has the potential for corrosion and you can't torque it down much because it's only secured by a 6mm bolt. A MG certified mechanic said that when was in CA for training this was mentioned. I moved that ground to a higher and slightly more protected spot where it is now attached to a 10mm stud and I can easily check to make sure it is clean and secure. Finally, I have had problems in the past (on other bikes) where the starter was trying to draw more current than the wiring would support, leading to slow cranking and finally damage to the starter.

Your concern about damage to the battery is a new issue for me, never heard of it happening but lots of things get past me. I'd expect the battery problem to be present when one has lots of power hogs running at the same time and for a long time so heat could build up. Riding two up with both people running heated liners and gloves, along with aux lights, heated grips, and who knows whatall comes to mind. Cranking the bike for 2-3 seconds...I'm not so sure.

I guess I'll be able to make a more informed reflection in about 10 years or so when I count the number of batteries I have killed or the number of times I have been stuck on the side of the road due to an electrical problem.