Speedo "floating" at mid/high speeds

[mike-s]

For the hell of it i took the GSX down to Wollengong to blow the cobwebs out and see how much of a tweak she needed.
She seems alright on the flats and struggled more than i thought in the top end (going to check the plugs as well as advance to try and sort that)
However one thing that made things slightly worrying (considering it was the last day of DD's) was the fact the about 20 minutes into the 110 zone my speedo started floating along at around 10km either side of what i would estimate to be my speed. Now i know to check the drive gear on the front wheel, the drive cable and its connecting lugs as well sa the odometer itself. Is there any area that i should keep a look out for more than any other? The thing works pretty well at lower speeds but is starting to be a real pain in the arse when your above slightly-crap-traffic speeds.

The other thing i identified before all this was i need to keep a better eye on my oil levels. I did an oil change before i left and around a litre or so came out, meaning aside from oil caught inside the engine there was about 800ml awol . This was after around 2000km!. When it was really misbehaving the bike was also experiencing a busted fork oil seal, so it was hard to tell what was leaking out with the oil spraying out with every bump in the road. I'll be keeping a watchful eye on this in future.

But yeah, any ideas about the speedo?

[oldman]

My 2004 Z1000 speedo floats above 150 MPH. I tried to fix it and the dealer said I should not be going that fast. I have not a clue what is causing your problem. What I did is was calculate my speed VS. RPM and that seems to work. Good luck.

[mike-s]

Well that's how i figured out how fast i was going as i knew 6k in 5th was 80km/h and just stuck with that & 8.25krpm for 110.

[MickLC]

The speedo on the Surfer was getting a bit wobbly and I'd noticed the cable was starting to fray a bit so I replaced it with a new one and 86.7km later it stopped working completely. Turns out it was the speedo drive that was on its way out...which reminds me to hassle Gos about whether he's found one in the 4th yet

[mike-s]

Is that at the top or bottom end (of the cable) mick?

[MickLC]

It was the worm drive running off the gear on the wheel hub. All the splines were worn and one was worn just a bit too much.

[mike-s]

Did a repeat trip today, and the floaty speedo problem didn't make a reappearance, strange
Anyway, new plugs, and i set the timing to be as close as possible to correct (i suspect the springs on the advance are a bit weak due to age), and it won't set to exactly correct (i'll take to it with a mini file and modify it to make it retard slightly more). Even as it is now, it works a hell of a lot better and on the flats the top speed is now a good 10-15km/h more, and it doesn't seem to crap out/fade at the top end anywhere near quite as much.