The cable just drives the speedo. It has nothing to do with calibration.viper33 said:Ah...true, i didnt think about that
so does this mean that the cable would calibrate the reading?
coz i had no idea that a cable would decide the speed based on the revs
i mean i thought any cable would do the same job
The speedo drive unit on the front hub is calibrated to the diameter of the front wheel. It is geared to turn the cable at a set RPM for a certain speed. For example, 80km/hr is about 3,000rpm of the cable (I think). This is fairly consistent across most bikes, so you can change speedos between different bikes with a fair amount of confidence that the speedo will still read true, even if it has come from a Kawasaki and is now bolted to a Yamaha.
However, if you change the wheel diameter and keep the same speedo drive unit, or replace the drive unit with one from a bike with a smaller or larger front wheel, the speedo will be out.
On an MC19 you can change the gearing by fitting different sprockets and your speedo will still read accurately because it is driven from the front wheel. The gearing does not affect the speedo reading.
However, on an MC22 the speedo is driven from the front sprocket, so changing the gearing has the same effect as changing the diameter of the front wheel does on an MC19.
Any cable will do the job as long as it is the correct length and has the right ends to fit onto the speedo drive unit and into the back of the speedo. If you take your old cable outer into the shop you should be able to match it up with one, provided that they have any in stock. Most bike shops don't.
I would imagine that a Spada cable would be a very close fit, if not a perfect match.