Tire Size Questions, Front & Rear

I am looking for some wisdom on tire sizes. Firstly on the rear, the previous owner of my bike had a 110/90-19 on the rear. Searching the forum, I have read that the rim is not made for that tire but if you want the wider tire get a 110/80-19. Using this size greatly reduces the amount of brands available. Secondly, the previous owner had a 90/80-21 on the front which is a little wider than stock. What are the advantages/disadvantages of the wider tire on the front .vs. the 80/80-21. Thanks

Tire sizes are only comparable within the same brand of tire. And often only within the same tire designation.

Your bike came with a 1.85" rear rim and a 100 width tire. That rim can accept most 110 tires no problem. It will be slightly wider (10mm in theory) and heavier. Usually a wider tire means more traction, sometimes too much for this smaller engine.

A 110 Michelin will not have exactly the same width as a 110 Maxxis and so on.

Some people like it, and some do not. It will depend on the track, tire itself and the rider´s liking.

The smaller rim will (with some tires) make the tire profile rounder, although not by much.

I personally often run the wider tire.

As for the front, a wider tire will leave a wider footprint, but can feel bouncier if it has a larger volume than the other tire.

90/90 is translated as width 90mm, and the second number is the tire side height in % of the width.

A 80/90 tire will be narrower, and have sidewall height 90% of 80mm. So this tire will hold less air and give different feeling. It will also put more pressure on a smaller surface.

All of this, including tire pressure variations, requires too much testing for a casual rider really.

Bottom line is, test for yourself! No tire will be downright wrong, as long as it fits the rim. You are the one who has to feel comfortable riding with it.

I prefer to buy tires from the same place, this way I know they will have the same tires every time. And when feeling brave I try out a new tire:thumbsup:

Thanks D-K, good info.

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