Can someone explain to me why...

[yadada]

I'm not gonna be a lot of help here, but if can jump the bike without starting the motor on the car.....I just saved some gas!

[Guy_b_g]

Tyler,

The transil diode setup on the Guzzi Centauro was wired into the power circuit between the ECU and the fuze box. On the Guzzis the voltage regulator had to have a good battery to clamp voltage properly and there was another problem...our regulator was mounted behind the headlight...so...the only route to ground was thru the steering stem bearings, this also created voltage variations and spikes at times...but the worst would usually only happen when a battery died. Most of us put in a ground strap to the frame, bypassing the bearings.

In our case it was our own alternator/regulator doing the damage...not the vehicle you jumped from, and bump starting was as bad as jump starting.

The transil diode would shunt the voltage thru the 10amp ECU fuze to ground. You knew you had experienced a spike when the fuze blew, some members also replaced the 10 amp fuze with a 5 amp fuze to further reduce the parameters under which you knew you had experienced a spike. You just carried an extra fuze or two. 90 percent of owners who had done this mod never experienced a blown fuze, (5 or 10 amp), and those that did never experienced a fried ECU. The guy who came up with this idea was an electrical engineer who was one of the members.

I doubt there would be any benefit for us to do this to our bikes, but since I am not an electronics expert, I just thought I'd throw it out there as an idea for the experts to look at..

[T99Ford]

Guy--that is an interesting idea, and I can see where you could run in to the kind of electrical problems you described by having the only ground provided through the steering system.
Anyone else who has ever damaged electronics by jump starting did so by jump starting the unit improperly. I have been a lead field service technician in the agricultural industry for 15 years. In that time, I have jump started systems from balanced 6/12 volt to 12 over 24, to straight 12, to 6v positive ground, to any other kind of system. I've jumped from cars, trucks, welders set to the proper voltage, and battery chargers. The current production tractors and harvesting equipment run up to 10 on board computers (controllers) monitoring every function that equipment does. They are contolled by space age CAN bus systems, just like any auto. Nearly every control in the cab is electronic, not manual. I have NEVER had a single problem personally by jump starting anything, running or not. I have never even heard or witnessed jump starting damage unless it was done incorrectly by someone who did not knowwhat they were doing or understand the processes involved. This includes people who touch the cables together prior to starting, to ensure the cables are connected (?!), those who connect the batteries backward, in the wrong order, and even those who ultimately blow the battery up in their face by doing it wrong. The XS1100 is 12v negative ground charged by an alternator, changes AC current to DC current with a rectifier diode, just like any car on the market in the last 40 years. The two systems are completely compatible, if the guy with the wires knows his stuff. There is no "magic" that occurs with any of these systems. They are as straight forward as they come. I will repeat again, if there is a problem, and the jump start was performed properly, ther will be a ground issue on one or both vehicles involved.
Lets not overthink this. After all, it is only a motorcycle, right?

[T99Ford]

By the way, when I said "guy with the wires", I didn't mean you, Guy

[Guy_b_g]

hmmmm....I guess what you just said meant...more ground straps may have a benefit....but our bikes don't need anything else..................right?

[T99Ford]

No, I just didn't want any of what I said to be taken personally. I'm just trying to help clear the waters. But as long as you said it, if all the grounds are clean and tight, you shouldn't need to add more!
While we're on battery etiquette, though, I noticed last night that a few cells in my battery were low on water. I didn't have any distilled water in the house. But...it was raining outside. I filled a container with the runoff from the rain gutter, made sure ther were no leaves or spiders in it, and poured it in. So here is the new question: What is the health benefit to the wellbeing of the bike to switch from plain old distilled water in the battery to fresh, pure, Montana rainwater. The bike's starting system is already 1200 miles younger!

[trbig]

I just saved some gas!

As he jumps on and takes the LONG way to his destination since he's on the bike! I guess saving gas so he CAN take the long route!? lol

I do stupid stuff like that. I'll gladly make two or three runs into town on the bike for stuff, but if I have to drive the car into town... ehhh.. it can wait until tomorrow after work!


Tod