So, I go to Iraq for the summer, which sucked, and I let my friend borrow my 900RR. A few days before I get home, something happens while he is riding it and he loses all power to the bike. The main fuze blew, and the battery fried. He managed to fix everything on the bike except the running lights, tach, speedo, turn signals, and LCD in the dash. The dash illumination lights work, and so does the neutral and oil pressure light.

He also told me a 10A fuse (ignition) kept blowing, so he put in a 20A (which is a no no), and it didn't blow. Then he put the 10A back and it didn't blow either. That tells me that whatever was causing the fuse to pop checked out, and I think it is in the dash.

Any suggestions? Has anyone ever seen this before?

 

I'd say, just to eliminate possible causes, and since they go out like crazy. Check the stator and reg/rec. Could be that the reg gave up while your buddy was riding it and it sent too much power down the line causing everything to blow. If he just replaced stuff with higher rated stuff the problem might still be there and you risk your ECU frying. If those are still ok (I doubt they will be) check for ground issues at all connections. You can also take every connector apart and spray it with WD40 and reconnect. Also pull the main ground from the engine and sand around the base where the wire connects to the frame to make sure you have good contact.

 

Monk.. I have done all that. I have no idea what caused the problem, but basically anything that had current running to it at the time of the "incident" fried. The turn signal relay cooked, all the bulbs in the running lights popped, something in the dash popped, and I think the ECU gave up as well. I don't have any continuity in the tach signal wire.

I have replaced everything but the ECU, so everything works again but the tach. I tested the reg/rec, and it checks out. If I am not mistaken, when those things fail, they just fail and are done. They don't fail for a sec and then start working again normally. Plus all the wires from the alt and reg look good, they usually melt if there is an overload.

Thanks for the input, and if you have any other ideas, lemme know!

 

Have you checked to see what the voltage coming from the stator is? should be about 50vac at 5krpm. All you're describing sounds just like a reg going out and letting too much voltage go downstream.

Have you done the electrical system fault finding checklist??
http://www.electrosport.com/technica...ding-guide.php

 

If the fuse popped, you had a short somewhere in the wiring harness. Look for exposed wires in the components that the fuse controls. jd

 

check your stator wire harness, if the reg went bad it seems to melt the stator wires and a short could result. i went thru the same thing, when i replaced the reg,stator, the staator came with new harness.