Ok, so here is the deal.
My roommate rides a 1998 VTR1000 Superhawk. I work on alot of bikes, but more the american Vtwin variant. I was hoping to reach out to people far more knowlegable about these bikes than me before I go chasing down ghosts in the wiring.

Symptoms:
-3 Days ago the bike shut down cruising down the road. I checked the fuses for him, and the ignition fuse was blown. Replaced it without a second thought, bike fired right back up.
-Rode fine for the rest of the evening, except two times as I rode next to him it sounded like one cylinder shut down for a revolution or two "popped" when it would ignite. At the time I chalked it up to fouled plugs from the bike shutting down.
-Later that night, after one more loud fire, rode about two miles, fuse blew again.
-Replaced fuse, rode home. The next day I took it for a ride, rode great, excepting at one point after about 2 miles of pushing it, stuttered and banged again, then rode fine for about another half mile when the fuse popped again.

The "stutter, bang" I keep describing reminds me of a fouled harley plug, or on a very very old bike if you hit the kill switch, let the cylinders load up with fuel, and reignite the switch.


Any help would be greatly appreciated. If anybody has any insight before I go mucking about in this wiring, or a wiring diagram of the ignition system.

Thank you!!!
McFixxx

 

Check the R/R (Regulator/Rectifier)... It's a good bet that it will need replacing... they have a tendancy to go bad, and then symptoms like these are pretty common...

 

R/R is one of the achillies heels of this bike (the other being the CCTs)- if you do replace it, look into replacing it with one that doesn't have a tendency to burn out. How-to's on the site explain replacing it with a Yamaha R1 R/R and if you don't feel like going that far, at least get one of the newer R/R's with fins on them. The ones on the '98 are a solid block and have a hard time dissipating enough heat to keep up with the electrical system.

 

Thank you for the help, if I can follow up with a few more questions...

Has anyone had this particular problem and fixed it with a R/R unit?

My concern is that it appears on the wiring diagram that the R/R unit is tied into the "main" fuse, not the ignition. So even if the rectifier portion went bad and this thing flooded the system with A/C current, it should blow the main fuse instead, at least on paper. Additionally, all appearances are that the bike is charging normally...

 

Yeah, me.

When my rectifier failed the voltage from the stator was zapping the bike with high power current, fried the fuse after the lights.

To be on the sure side, when I replaced the R/R unit, I also did the stator and battery. Suspenders AND a belt, ya know, no problem since.

 

Really. Huh. Its not that I doubt anybody hear, quite the opposite. That's why I ask. I've had some of my Harley's do things that shouldn't have happened. And you were popping the ignition fuse? Any other symptoms? Runnability, electrical or otherwise?

 

R/R, replace it or keep going till you fry your ECU.. it's your call.

 

the R/R is your best bet on the problem.see if its stock,if so.change it.but ofcourse make sure there is no burnt wires or bad ground.
but im betting its the R/R

 

The R/R can quite easily fail by overvoltage charging too... And if it does, the problem is most likely to be temperature dependant, ie start the bike and measure and you get the specified voltage, when the diodes in the R/R heats up, they let through say 15-16V to the fuse box that goes POP... Keep doing it enough times and the electronics go bye-bye...

No matter what your actual problem is now, changing out the R/R if it's a stock 98 item is on the list of things I'd prioritize doing... As in, do it before it takes something expensive out...

But yeah, I honestly believe it's causing your problems, or at least contributing...

 

ours did the same thing last year bought a new regulater rectifier from a place n canada an no troubles since. can't think of the name but it was a newer style think it was about 60 buck's or so road it about 8000 after replacing it. Rode everywhere on it love the heck out of it. let me know i can get the number if u need it