FZRSupport: the FZROnline Archive

The tachometer on my bike wasn't working when I bought it, I tried following the wiring diagrams from the factory service manual but the previous owner of the bike did a nice job of hacking up the wiring (near the gauges, the rest of the harness seems intact) and painting it silver so that's made it pretty hard to troubleshoot the problem. I went to autozone and bought a cheap tach to test with, it works with 4/6/8cyl engines and is suppose to support distributorless ignition systems.The factory tach needle only goes up to 1000rpm (at what sounds like it should be around 7-9k rpm) regardless of the actual rpm and the test tach goes up to 3k rpm (at what sounds like it should be around 7-9k rpm) and fluctuates between 600-1500 rpm at idle. Are there any common problems with FZR tachometers that I should look for? Also, do our bikes have rev-limiters? I'm scared to stay in any gear too long because I don't want to over rev the engine and I don't want to find out the hard way if there is a rev-limiter or not. Google doesn't turn up anything helpful on either subjects.

I had two tachos wrecked by faulty voltage regulators although it doesn't seem to be a common occurrence. It may be that the tacho from auto zone is only amplifying the signal to half of what it is supposed to be. From memory three wires go to the tach; one is 12v positive, one is earth and one is the signal wire from the TCI.

Rev limiter kicks in at 12.5K

Have you tried a new wiring harness for the gauges?

There is one common problem. If the wires are grounding out on anything, you could have blown a fuse. This would cause the tack not to read above 1k rpm. I know because it has happened to me. Unfortunately, just swapping the fuse does not solve the issue because as soon as you turn the key on, it will blow the fuse again if there is a wire still grounding out. First thing I would do is check your fuses. Then get the wires sorted out if any of them are in the wrong place. Then get the wires separated and wrapped with some electrical tape (wire connectors and heat shrink tubing is preferred here). See if that doesn't fix it. One notorious wire to look for are the horn wires. They are just long enough to hit the frame or radiator and ground the system out. I went through a 20 pack of fuses before I found the wires before.

Good luck.

Thanks for the help, I checked all the fuses and they are ok, so I'm not suspecting a short to ground in the wiring harness although a broken wire is isn't out of the question. There are a couple cut wires in the dash area so even if they aren't related it would probably be a good idea to replace the wiring harness for the gauges; I'm just hesitant on throwing parts at the bike to fix a potential cheap/easy problem. I'll check ebay and see if I can get a new harness for cheap. I'm guessing if it were an issue with the TCI the bike would probably not start?