'83 Tach Stuck @ 3500 Rpm

Have an '83 VF750 and the tach has been stuck for the last two years and I would like now to fix it. According to the repair manual it could be a spark unit or deab tach. When they say spark unit do they mean the ones at the back under the seat?

 

I don't know what they mean by spark unit, unless they mean the pickup. It mught be the tach has a burned circuit or something. I had a trans am that a component on the circuit board burned and the tack quit qorking altogether. Ihave not experienced this type of problem on my bike (or any other) but maybe someone els has. You can use the search function to searchthe forums to see if there is a relevant thread.

On another note, Welcome to the forum. We are glad you found us and decided to join. We have a member map where you can show other members wher you are and we have a chat room which is available 24/7 and also we have a scheduled chat session for tuesdays at 7:30 PM PST. You are more than welcome to join us there as well.

Vinny

 

Thank you for the invite but I will be working hard to get my bike back on the road tonight.

There are three wires going to the back of the tach if I disconnect them would it reset it? Do you you any other way to test it?

 

I am not sure it can be "reset" per se, since it is not digital. You could probaly take a volt meter and teast each lead. To be really effective with advice I would have to look at a manual to see where the wiring goes and and to troubleshoot it properly. Do you have a service manual to help guide you?

 

thanks for the help vman38. I got it apart last night & found the problem to be a small metal spacer in the instruments had come loose and the magnetic coil in the tach attracted it and the needle was stuck on that so cleared the jam and all is good now. Thanks again, can't wait to see that 10G rpm marker again.

 

just about to post that the spark unit, also known as an ignitor, would not reset the tach if unplugged, but that you can check continuity of the wiring. I had to look in my service manual to find out what the spark unit was as I have never heard it called that. Guess the manufacturers cal it by different names. Anyway, if th econtinuity of the wiring between the spark unit and the tach was within the limits in the manual, the manual says the tach would need to be replaced, and if it was outside the limits, the manual says to replace the wiring harness. But since you got it fixed it's a mute point, eh? lol