I bought a 2nd hand CBR150 two years ago and the previous owner had put a bigger tyre on the back and gave me the original tyre as a spare. Now it's time to replace the back tyre I'm wondering whether I should just buy a new one or whether the old one which has been sitting on my balcony out of the sun would still be ok?

--damole

It is probably OK, BUT...why risk it? Tires for a cbr150 are fairly inexpensive. A tire failure will cause you some major problems.

Bigger meaning wider? In this case a bigger tyre will give you better grip. Going back to a smaller tyre will disappoint; I should buy a new one same size as the existing one?

should just buy a new one or whether the old one which has been sitting on my balcony out of the sun would still be ok?

You're kidding right?

Considering the original IRC tubeless is fairly good, I'm not replacing mine just yet at 10K. But T Dog's original balooned and almost popped. He switched to Michelin, and so will I. The rear is maybe wide enough, but an old used one is just a mosquito nest.

Thanks for the replies.

I found this on Motor Cycle News, nevertheless I decided to buy a new one, I visited Chiang Mai Bike Shop on Mahidol Road, 1700Bt for a Michelin 100/80-17, I think he said Sport but I wouldn't swear to it. I went to P Dang on Chiang Moi road, the road that leads to Warorot Market, 1050Bt for IRC 100/80-17 and 1100Bt for IRC 110/80-17. The tyre that was on the bike when I bought it was a 110 so I went with that.

The decision for me was safety first of course followed by carbon footprint, the IRCs are made here in Thailand, the Michelin imported from Europe so as I probably don't need the extra performance it made sense to buy locally made.