"New" 1985 VF700F Issues

Just bought a 1985 Interceptor VF700F. Went over the whole bike before buying as with any other. Overall, it's cherry. Looks great, rides great, nice deep growl that sets off car alarms.

First things first. I live in Brooklyn and commute to Manhattan. Naturally, the test ride lasted about five minutes, so I first noticed that the fan wasn't kicking on until my first commute. I had to stop twice to let her cool down.

At work, my boys and I linked up the fan to the hi-beam. Quick fix, works great until the next evening. Ready to head home, hit the starter, everything goes dead. With the key in the 'on' position, everything blinks on again after five minutes or so. I pop-start her and ride home. After arriving home, i turn the bike off, turn the key back to 'on', and there's nothing at all. After pulling apart the high-beam/fan rig and setting it up normally again, I replaced the battery. The vent/overflow hose had been kinked, wedged beneath the old battery and the tray.

After the new battery, everything's fine. Fan kicks in slightly above halfway on the temp gauge, and I put about 400 miles on a weekend trip with no problem.

On the way home from work today, at the end of the Brooklyn Bridge, I look at my temperature gauge. I'm in the red. Look down, the stubborn little fans are shirking in their duties again.

The other thing: at about ninety-five, she really starts to shake. Could she simply need alignment? Balanced tires?

That's it! Thanks for reading! I've got an incredible bike!

 

2nd question first...I want to live where the speed limit is over 95mph:biggrin: . Check air pressure in the front tire. If pressure ok replace it. As far as the fan goes, I put a switch on mine so I can turn it on whenever the temp guage goes up. The fan usually won't have to run unless in stop and go traffic, so a long trip may never cause it to come on. You might have a bad sending unit on the fan. It is located in the bottom of the radiator, and has 2 wires going to it. You should have 12v on one of the wires whenever the switch is on. The other wire goes to the fan. Also check that the fan has a good ground. Good luck. Hope this gives you somewhere to start.

 

Thanks! So.. Bring her up to the temp when the fan would normally kick on and run a voltmeter to the sending unit? If the fan's working one day and crapped out the next, my suspicion is a bad ground. I've had poorly connected grounds jostle loose before on these scabby city streets. In the end, I'll probably just follow your lead and do the manual switch on mine, too.

Now that I think of it, I had that shuddering around 85 or 90 on my old Yamaha XS11 (is 90 some sort of sweet spot?). Replaced the front tire, and everything was fine. Just have a lousy memory, I suppose. How do you fix that?

 

The only time I ever had a shaking on my '83 Interceptor turned out to be low air pressure in the front tire. It should be smooth all the way. Check the steering head bearings. May be loose.
The switch will bypass the sending unit, but you'll still have to make sure you get a good ground to the fan. Make sure you have 12v on one of the wires going to the sending unit whenever the key is on. The sending unit will send voltage to the other wire when it comes up to temp. I put the switch on mine so I can turn it on whenever I want, but left the sender hooked up, in case I forget to turn it on.

 

Good call, steering head bearings or wheel bearings. If the tire is good. Many of these older bikes have very old tires on them. Those tires are not good.

 

Thanks! Checked the ground and the sending unit. I'm surprised the fan worked at all. The connections were a mess. A snap-off blade, sandpaper and WD40, and we're clean as a whistle. Haven't taken her back into traffic yet, but hopefully that was the problem.

 

NO matter what happens, don't let it get too hot. It will smoke the cams!
Can you say ka-ching? Lots of bucks.