I'd actually go the other way too perhaps?

I've been running the TKCs at 30psi recently as I've been almost always on tarmac, and they seem fine (I'd say any more than that is too much), but have been very happy with them at 25psi - particularly in mixed conditions.

As others have suggested, if this is Lairy's first set of knobblies, then they will feel different to ride on, but they soon bed in very nicely and are surpisingly grippy - I was riding round the outside of the Harley boys (not that hard, admittedly x) on Deal's Gap last weekend, and that was on a squared off rear with 5000 miles on it!

TKCs rock!

xxx

ps. As for tube vs tubless, I believe for the rear is only the 150/70 that is specifically tubeless (although you can always run a tube in it as others have said), however, I recall they do produce both types of 21 inch front - tubeless tyres tend to have a slightly different bead as the rim shape is different (to help seal properly) - as others have said, if you're running tubes anyway, it doesn't matter - it's only if you had tubeless rims (and running them tubeless) you should specify the correct version of the tyre.

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