bigger tyres?

On or around 05 Mar 2004 08:05:22 GMT, snipped-for-privacy@aol.comnojunk (Cdunn53) enlightened us thusly:

why, in particular? 255 are plenty wide enough for normal purposes. I've got 10.5" wide on my 110, (about 265mm) which, sometimes, are too wide.

The normal rule is "up 2 sizes, down 10% profile". But it's easy enough to work out:

nominal tyre height is 255*0.55*2/25.4 inches (11", if you work it out) so nominal diameter is 18+11 = 29"

working it backwards, you'll want 285/50 if such are available, to keep the diameter the same.

if you fit 285/55 then you've upped the nominal diameter to 30.3", which will upset yer speedo and milometer slightly (about 4.5%).