Recently i've changed my front tire from 2.10 to 1.95, but i'm still using 2.10 for my rear tyre. What different does it make. Can somebody explain to me more detail on choosing a right tyre.

-- lan (lant31@hotmail.com), July 01, 2003

Answers

Here are some of the things to think about when choosing a mtb tyre:

• casing width. The wider the tyre, the larger the contact patch on the ground, and the better the traction. A larger tyre also allows you to run it with lower pressures without risking a pinch flat, giving even more traction because the tyre conforms to the shape of the terrain. OTOH, a wider tyre is less suited for extremely muddy conditions (less clearance, and tends to 'float' on mud rather than digging into the substrate beneath the mud).
• kevlar or steel bead. Kevlar beaded tyres are lighter, can be rolled up, and costs more. Steel beaded ones are heavier, can't be rolled up or folded, and are cheaper.
• tread pattern. There's a lot going on in tread pattern design. Tall knobs dig in well, but if they're closely spaced don't shed mud well. Tall knobs "squirm" in corners on tarmac, shallow knobs are more reassuring on the road. Shallow knobs don't collect mud, but loose traction quickly in wet and slimy conditions. Front tyres are sometimes designed with forward pointing knobs, this helps prevent it from wandering sideways in corners.
• tread compound. Softer rubber is said to grip well, but wears quickly.

For me, I buy the cheapest kevlar beaded tyre in a reasonable size (2.0 to 2.1) which can be used for the front and the rear. The last pair I bought, in Sept last year were the Ritchey WCS 2.1, only RM40 each. Here's a link that might also be helpful.

Joe

-- Joe (joeadnan@yahoo.com), July 02, 2003.

I have read from magazine, they say that if you are on the heavier side of the scale then you should use bigger tires. I am one such person and i used to use 1.95 on my bike. They wear pretty fast and I also get alot of punctures. No idea on how it will effect riding when using 2 different sizes on a bike. Hope some one will shed some light on this.

-- alex c. tseung (alex_chin_41@hotmail.com), July 06, 2003.

Ian,

Theoretical only: In a straight line, when you slam your brakes full on, all the weight gets thrown to the front tyre. The rear just skids. So a bigger front tyre would be desirable.

The right tyre? You just have to pick the tyre that suits your riding style, terrain and whether your bike is a hardtail or not.

To answer the other part of your q, some opinions:

Mud: skinner the better, since they have less floatation and sink in to the hard ground underneath. Less mud is picked up by your chain stays and chain as well, the latter delays chainsuck problems. skinny = light as well.

Firetrails: Any old bald tyre with some side lugs, pumped to higher psi.

Rocky: Big fat ones with soft knobs.

Full suspension bikes can afford to run skinnier tyres with lesser risk of pinchflats.

BTW, Another important factor. Sidewall gnarliness! I've found that tyres with aggressive sidewalls will still grip in the dirt and off cambers even with the centre knobs worn through!

So, if you're a cheapo like me, you can use them until the sideknobs are peeling off the carcass!

-- James (jmzyap@yahoo.co.uk), July 07, 2003.