tach needle going crazy...

[edwardvdh]

hmmm... so my friend and i were riding back home from the mountains yesterday, and when we got off the expressway the tach started going crazy when you reved it. crazy meaning... sit at a stop light and its idleing fine... a bit high actually... hit the throttle and the tach needle shoots up and down like a bungie for a couple seconds. the actual engine revs are fine and normal.  is this a bad tach cable? its a '93 so its still a mechanical cable. funny thing is, today it worked fine again. maybe the long trip overheated the cable or something? and ideas? thanks!

edward

[kml.krk]

I bet it's inland Bermuda triangle... 

[gsagent005]

 

[edwardvdh]

haha... ill have to keep an eye out for that.

[jp]

Check both ends of the cable to see if it's loose. If it's just a little loose, it may skip when you rev and then start working again when the engine speed settles down. You may want to lube the cable while you're at it.

[Porkchop]

Check both ends of the cable to see if it's loose

+1 on the checking to see if it is loose.  Mine did the same thing and tightening the cable connection fixed it.

[jiggersplat]

be careful not to strip the hole on the head where the tach gear goes in

[pronator]

Is there an O-ring at the end where it connects to the head? About three inches of the cable (engine side) has gotten coated with what looks like oil spittle over time. Haven't taken it apart but wondering if I just need to replace the O-ring.

[edwardvdh]

alright... ill check the tightness tomorrow... was thinking that too but havent had time to look.  also.. is it ok to use normal motorcycle oil to lube the inside cable? or should i use something else.... i think ive already used motorcycle oil on it once before... was that a bad idea?