(iarocu) writes:

Skunk wrote in message ...
I have a second hand trek 6500 mountain bike. I love the bike but hardly
use it off road. The back tyre needs replacing. Could/Should I change it
to a road tyre if I'm hardly going off road. The front tyre is okay
tread wise(off road tyre). I am a bit skint, are there any problems if
I run it with the original off road front tyre and an on road back
tyre?

Try a Continental Top Touring 26x1.75 on the back. A fast rolling tyre
with a slight inverted tread which will copew with mild off road but
be noticably faster than knobblies.

IME it's noticably faster than most slicks, given its flexible
carcass. I know also that the knobblies I rode in on today are faster
than my slicks for the same reason (GEAX Beaumont knobblies vs. Maxxis
Xenith slicks)