According to a moto dealer, if I put a 130/ 90 17 knobbly on the rear it will increase the rear circumference by 26mm?

Has anyone put a tyre on this size and can comment?
Did it throw your odo out (because they are so accurate standard).
Thanks

According to my fag-packet sums the difference in diameter will be roughly 52mm, so it looks like your moto-dealer made a mistake (he gave the increase in radius)

The difference in circumference would be ~163mm.

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Estne volumen in toga, an solum tibi libet me videre?

So will this throw the speedo or odometer out? Not sure where the tenere measures this from , rear wheel or front wheel?

It would be out by 8 or 9%. I don't know where the speedo sender is either, but gearbox output is quite likely.

You can use these to recalibrate your speed if required http://www.bikersdiscountstore.co.uk...r-v4-pd-18.php

However, as speedos show higher than the true figure and a larger tyre will cause a lowering of the reading, you might end up fairly close to the truth anyway!

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Estne volumen in toga, an solum tibi libet me videre?

Thanks HCR. Will give it a crack and see what happens

As XT speedos read about 8% over with a 130/80-17 stock tyre, with a 130/90 the speedo will theoretically be spot on with actual road speed. However, your odometer will under read by 8% or so, as with the stock tyre size the odometer is pretty accurate.

You can't win really. Even fitting a speedo healer can't correct both the distance and the speed readings, you have to pick one or the other to get right. Alternatively just don't worry about it! Get used to how much "out" the speed is an adjust accordingly in in your head.

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