Fitting electronic tachometer to 3000m

[Erich Stahler]

Has been working correctly but needle has recently started bouncing around at anything over 2k revs.
Taking the signal from the negative side of the ignition coil, can only assume it's picking up noise, has anyone had similar problems and how have they overcome?

B.T.W. still running contact breakers, not electronic ignition which some times causes issues.

[plasticpig72]

Have you tried fitting new points and condenser.
I have heard it can be a sign they need replacing.
Alan

[Erich Stahler]

plasticpig72 said:

Have you tried fitting new points and condenser.
I have heard it can be a sign they need replacing.
Alan

Hmmm, will give that a try.

[Erich Stahler]

Erich Stahler said:

plasticpig72 said:

Have you tried fitting new points and condenser.
I have heard it can be a sign they need replacing.
Alan

Hmmm, will give that a try.

Alan, You get the prize, changed the condenser and no more bouncy needle.

Interestingly whilst trying to get the the bottom of the problem found a an article that says SPA tachometers, which is what I have, seem to be particularly sensitive to spikes.

https://www.pegasusautoracing.com/document.asp?Doc...

[plasticpig72]

Well done that man and for the price of new points + condenser peanuts.
Alan