A few things I found on my 87

[Reddog170]

Well my 87 had a real bad 7 years. In short it was crashed, repaired, left sittig. I got it for some labor. The windshield was missing, the clutch lever was broken, the battery was gone. I "borrowed" parts from my 83 and put a new battery in it. Changed the oil and it fired up, pretty easy actually. Now when I test rode it it fell on its face when I opened it up. No power. So I had planned a big carb cleaning and tune up. When I got in to get to the carbs I found the airbox was not even hooked to the carbs, it was just sitting there. I got it seated in place and a new air filter in. I put new plugs in it and checked over all other seals and what nots to make sure I had not missed anything else. Took it for another ride. Much better. Responds like it should, still a little hesitation when you go from 1/2 throttle right to wot, but getting better.

Now here are my questions. The tach, no where even close to right, never reads over about 2500 rpm. Any idea why? also the temp gauge, barely gets off the cold pin. I know it gets warmer than that, again why? If anyone may know why these do not seem to work right I am all ears. Thank You, Shaun

[Condor]

Well my 87 had a real bad 7 years. In short it was crashed, repaired, left sittig. I got it for some labor. The windshield was missing, the clutch lever was broken, the battery was gone. I "borrowed" parts from my 83 and put a new battery in it. Changed the oil and it fired up, pretty easy actually. Now when I test rode it it fell on its face when I opened it up. No power. So I had planned a big carb cleaning and tune up. When I got in to get to the carbs I found the airbox was not even hooked to the carbs, it was just sitting there. I got it seated in place and a new air filter in. I put new plugs in it and checked over all other seals and what nots to make sure I had not missed anything else. Took it for another ride. Much better. Responds like it should, still a little hesitation when you go from 1/2 throttle right to wot, but getting better.

Now here are my questions. The tach, no where even close to right, never reads over about 2500 rpm. Any idea why? also the temp gauge, barely gets off the cold pin. I know it gets warmer than that, again why? If anyone may know why these do not seem to work right I am all ears. Thank You, Shaun

 

I'm thinking on the temp it might be a bad ground at the sensor or a bad sensor?? The sensor housing is located on the rightside forward on the motor. There's a brown wire going to a screw on the frame. On the tach... I think the pulse is picked up by the #2 piston. Maybe a bad lead?? Never been there before so this is just a shot?...

[bongobobny]

+1 with what Condor said! The other possibilities are, with the crash, the gauges themselves could be FUBAR...

 

Anything else bad with the dash? Maybe poor ground. As far as the tach, as mentioned the trigger for it is the signal coming from the #2 coil output from the TCI, could be a corroded connector somewhere between the TCI and the Tach...

[Venturous Randy]

Another thing to check is the by-pass valve behind the radiator. If in the wrong position, it will by-pass the thermostat and can run too cool. When looking at the face, the top of the letters should point in the 5 o:clock position.

Randy

[Black wing]

the tach will probably just take a while to wake up, ive always found them to be slow to respond after they sit for more than a few months.

[camos]

Seems to me with how long it has been sitting all the connectors and grounds should be taken apart, cleaned with electric contact cleaner and if necessary with emery cloth or fine sandpaper. If the wiring is not well connected a lot of time will be wasted chasing individual symptoms. Once you know the wiring is good then troubleshoot the individual components.