Everytime I've tried to run a wider than stock rear tyre on a bike (including the Tenere) it's spoilt the handling - slower turn in, weaves, twitchiness, inconsistent heat build up/distribution and odd wear patterns etc.

Whether a 170 or 180 tyre will physically fit in the swingarm is one matter, but the X, having a 4.25" rim is theoretically limited to the following sizes:

Tyre size Rim width range
150/60-17 4.00 - 4.75
150/70-17 4.25 -4.50
160/60-17* 4.25 - 5.50
160/70-17 3.75 - 5.00
170/60-17 4.25 - 5.50

Anything outside of this will tend to result in a pinched (if too wide) or flattened (if too narrow) tyre profile and adversely alter the handling.

Most people (including me I'm embarrassed to say) only ever try and squeeze on larger than standard tyre because they think it looks cool. I've learnt my lesson through the mistakes I've made and become a little less style-conscious in my old age, and now stick rigidly to the OE sizes.

Does anyone really need a 170 or 180 section tyre on a motorcycle knocking out 43 rear wheel horsepower?

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