Erratic Speedo

Jim K · #1 (**permalink**) 04-01-2010, 01:34 PM

What can I do to calm down my erratic speedometer? I have already replaced the cable once after the wildly erratic needle foreshadowed its ultimate demise. I don't have any tight kinks, but it is wrapped around the tranny. The needle used to waver at <30 mph, now it is wacky up to 70 mph. My foot is steadier than that!

Gunner · #2 (**permalink**) 04-01-2010, 02:08 PM

Thoroughly lube the cable - use a good silicone-based lube.
Try to pull any sharp bends out by tying the cable to support points.
Get a longer cable if you can so that the bends can be made into fewer and larger radiuses.
When all else fails, go to an electronic speedo...

Zoom This · #3 (**permalink**) 04-01-2010, 02:52 PM

Gunner's right. I tried absolutely everything under the sun to get rid of my wavering speedo in my new SPF, 7 years ago. I sent the Smiths mechanical speedo to a shop in New York specializing in Smiths repair (Nisonger) and they said the speedometer would cost almost as much as a new mechanical one to repair. I told them I was not going to spend another dime on my speedometer so I bought an electronic Smiths speedo from them and a magnetic pickup for the tranny from Fortes to connect my TKO-600 to the new electronic unit. Speedo has been perfectly still at all speeds and is programmable for any tire size or rear axel ratio. Love it.

Jim K · #4 (**permalink**) 04-02-2010, 12:26 PM

Thanks for the suggestions. I appreciate the help from the cobra community!

Jim

Slow Dawg · #5 (**permalink**) 04-03-2010, 08:41 AM

Jim, you probably have a #3010 cable. We recently found out a #3015 has the same ends but shorter. As Gunner said, lube the cable, especially at the bend right behind the speedo. I like the electronic speedos, but sometimes cash is the deciding factor.

dlampe · #6 (**permalink**) 04-03-2010, 12:20 PM

Have you spoken to Brian about it? Maybe he would send you another gauge to try. That would help identify where you have a problem or at least rule out the gauge.

Jim Werth · #7 (**permalink**) 04-03-2010, 03:46 PM

I've seen 90 degree cable adapters before. No sure if any will fit a t 5. Jim

Jim K · #8 (**permalink**) 04-05-2010, 10:04 AM

I'm sure that the cable is at fault. This is my second one and when it went in new, it worked well. The first lasted 500 miles, this one has lasted about 1200.

I'd be interested in an electronic set-up, but I want to keep the original gauge to match all my other gauges. Are there any with a device that hooks to the back of the original gauge?