Two requests for advice!

[Dizerens5]

I have two problems with my 79 R65 - does anyone have any ideas?
1) I suspect that the electronic tacho (we say rev counter over here) may be reading too low. Is there any way of using a multimeter to check it?
2) the seat lock is very shaky mounted and difficult to use. I suspect that the tiny locking screw has not been done up tight and may have fallen out. Is there any access to the back of the lock without removing seat, fender, rear wheel etc.?
    Thanks!

[Bob_Roller]

The tachometer electrical connections may have corrosion on them, or possibly loose .

I have heard of problems with the printed circuit board inside the tachometer, developing cracks .

The wire for the tachometer, comes off of one of the coils, then goes directly to the tachometer .

It is possible to remove the two screws that hold the lock assembly to the frame, as long as a previous owner hasn't 'buggered' them up .

I've used a 90 degree ratcheting screwdriver, or a short #2 Phillips bit, and a ratcheting box-end wrench .

If you can get in there, put some valve grinding compound on the screwdriver bit, for a little extra 'bite' on the screw head .

Removing the rear fender isn't too bad of a job, I'd remove the rear wheel, to make it easier yet .

[Lucky_Lou]

+1 with Bob pull the plug from the back of the tacho and check for corrosion on the back of the pins also the gap up the pins should be even if any have crushed in prize them open abit.
I ditched the seat key lock on mine the seat locking mech works fine without it, if someone wants to get under the seat they,ll do it lock or no.The push button works fine without it.
Lou

[montmil]

After spending way too much time dicking with the seat latch/lock on my '81, I finally gave in and pulled the rear wheel and fender. S-o-o-o much more room and no more profanity or blood shed.

Monte

[Rob Valdez 79 R65]

+1 with Bob pull the plug from the back of the tacho and check for corrosion on the back of the pins also the gap up the pins should be even if any have crushed in prize them open abit.
I ditched the seat key lock on mine the seat locking mech works fine without it, if someone wants to get under the seat they,ll do it lock or no.The push button works fine without it.
Lou

And that plug is a son-of-a-gun to pull out, even when everything is fine.  You WILL swear and look for a screw up in that center hole, but there is none...
Persevere.


Some folks, that modify their airheads extreme, relocate the ignition switch to that lock hole on the side of the frame.

[Dizerens5]

Thanks you all, I've printed your advice and will follow up. Btw I thought all electronic tachos worked off the ignition system but I see that you can also buy one with alternator pick-up. Would it work on a BMW motorcycle? I suppose the alternator is basically the same as a car type. But at £80, over $100, it's a lot to pay for a two minute test! (These tachos are in the online cat of Vehicle Wiring Products, a UK company but known in the US I believe.)