140 tyre on rear of 700 ?

[weldit]

Hi all
I need to change my back tyre on my xl 700 and was thinking of may be trying 140/80/17 Tourance.

has anyone tryed it?
what do you think.

[StumpyFingers]

I have a 130/80/17 on the rear of my 650.
I would be wary of a larger tyre profile due to clearances of the swinging arm.

[Jimmcc]

Be wary of doing this as what can happen is that the tyre width is 10mm wider but the wheel rim size isnt 10mm wider as well so what can happen is that the Tyre profile gets squeezed by the rim width and ends up being a sharper profile than it was before so you dont get the big wide curve that you expect. Instead you get a tyre that has a sharper profile and the centre tread wears down quicker as the footprint is actually slightly smaller.

[Baggy]

... and am I right in remembering that if you get unmatched profiles front and back, you'll get very weird effects when you lean in corners ???

You don't say if the bike is the ABS version... if it is, you need to make sure the total diameter is unchanged - you'll confuse the ABS otherwise.

[StumpyFingers]

A 130/80 gives the same diameter as the standard 120/90, A 140/70 would be closer to the mark but a 140/80 would be the wrong size.

[Jimmcc]

All the 700's in the UK are ABS, certainly as far as UK spec bikes are concerned.

With a sharper profile on a front tyre the changes are noticable under normal riding conditions, as it will purn in quicker etc. On the rear a sharper profile is more difficult to feel the effects, although I must admit that when I swapped from the Blackbird to the 700 I was surprised how diiferent the riding positions make it feel. The BB was very much about the grip etc feels from the front tyre whereas the 700 is so upright and hence the front feels vague and yet every ripple on the road comes through the rear.
Ive not had the transalp long enough to swap rear tyres yet but on other bikes its all about getting the profile to give you the optimum footprint size for the lean angle that you use. You might find that it feels a bit like that knife edge feeling when you fit a new tyre and yet when you get a bit of a lean angle it holds the turn really well.
Personally, I would stick with the OEM size but choose a different tyre brand, Metzler have introduced a radial front as well as the radial rear for the TA called the Tourance Exp. Thats the one that I would like to hear about if anyone has fitted them.

Cheers, PS Bit disappointed that NO-ONE has replied to my thread about finding a good location for a tool tube to be fitted. Cant believe that I'm the first to fit one on a 700.

[Plasnart]

We don't need no tools!!!

[Jimmcc]

Good answer but I want it to carry an aerosol of tyre weld. As this is the first bike Ive had in years that has tubed tyres and therefore my tubeless tyre repair kits are no good.

[weldit]

thanks guys for the response and I think I will fit 130/80/17 Tourance and see if ok, if not will fit new front as well.
I onlt got 3000 out of the twing not very good.