A few weeks ago I bought a decent mountain bike. It's not a fat tire bike but it had pretty wide and grippy tires. I rode almost 200 miles over the past few weeks on asphalt but tires are going bald. I don't go mountain biking with it, I only use it on the bike trail which is asphalt. There is not much left now.
I am wondering what did I do wrong? is it normal? If I change the tired how long will they last?
Thank you.
'Decent' MTB means different things to different people. What are the actual tires' make/model and sub model?
Many manufacturers use the same tire mold for different tires with different characteristics. For instance Schwalbe make a range of tires (e.g. Nobby Nick, Racing Ralf, Rocket Ron) with various tread patterns for different terrain. With each in this range you can get various sub models. Apart from light weight vs puncture protection, there is 'Performance' and 'Evo' rubber compound. Evo does not last long, but holds on like a pitbull with a bone; Performance lasts longer, but is less grippy. (Using Schwalbe as an example here, not a recommendation)
If it is a high end bike, it's likely come with tires built for grip in loose surfaces, not longevity on paved surfaces. These tires have a soft rubber and wear very quickly on paved surfaces. 200 miles from MTB tires is not great, but not unexpected if they are a 'race' model.
For your next set of tires, look for ones designed for hard/paved surfaces, and unless you need (or want) the 'race' performance, go for model designed for longevity.
Most tire manufactures have good tools for tire selection on their web site, otherwise your local bike shop (LBS) will be able to recommend a tire suitable for the riding you are doing.
Well, when people buy a decent MTB and are like me then they don't do it primarily to ride on asphalt but to tackle gnarly terrain, where you want as much grip as possible even on steep rock faces, wet roots and deep mud. For that, a soft compound and low tyre pressure (no more than ca. 2 bar / 30 psi) are very helpful, but both results in higher wear and is anyway counterproductive on asphalt. You should select a pressure on the higher side, but that doesn't prevent the tread from wearing down. Really the only reliable thing that lasts longer is harder compound. Various manufacturers advertise that they have some fabulous secret that's both grippy and long-lasting, but don't expect too much. E.g. Continental has their “black chili” which is allegedly twice as grippy and lasts twice as long as other compounds. I've tried Der Baron... good tyres but after about 600 km I'm also pretty much down to a slick.
So: if you're riding mostly on the road, get some relatively narrow, hard-compound, small-tread tyres and pump them to something like 3.5 bar / 50 psi. (Adjust as needed for drag vs grip and comfort and of course check the maximum rating.)
Consult your local bike shop for an exact recommendation.
You should replace your current tires with a pair of "slick" or "semi-slick" tires. These are the tires that will best match the conditions you ride in. They are typically a lot more durable than off-road tires. Plus, they will be lighter and have a lot less rolling resistance, which you will certainly appreciate.
Bikes are quite specialized (pun not intended) for years and the spectrum is getting wider and wider.
As in any other field, define your needs/wishes first, think them thoroughly and then pick a proper tool. many will stone me, but there is really rough and not complete spectrum of bikes I can name now. Sorted from the smoother to rougher terrain:
Every single group has not only frames customized for the group, all the parts are optimized as well. Including tyres.
You have picked a bike optimized for rough terrain and used it on tarmac. MTBs need robust tyres to withstand possible punctures from rocks, branches which is useless on tarmac. They need soft and deep threads to follow the rough surface and deal with mud, which is useless on tarmac. MTBs are also of more robust construction to withstand jumps and other excessive loads caused by the rough ride, again, it is useless on tarmac. The gear ratios are shifted to lighter gears so one can climb in rough terrain easier (the rolling resistance of wet mud is huge compared to any dry and hard surface), which is useless on tarmac.
Soft tyres wear on tarmac so extensively because it is like a sandpaper for them. As bigger tyres are inflated to lower pressures (compare 2 bar for MTB and 8 bar for a road bike), they deform more so they slide all the time. In sand/mud the terrain let the rubber go through the soft material, tarmac forces the rubber to slide on its hard and coarse surface.
If you change the tyres only, they won't last long.
If you change from tarmac to dust/mud they can last few seasons.
If you change for smoother and harder compound, they will last longer.
If you want to stick with roads, I would recommend looking for more road-dedicated bike. If you want to stick with the bike, I would recommend changing where you ride.
By the way, MTBs are really tough bikes.
If your bike tyre has rim brakes, and is going bald in just one spot - this can indicate a wobble / protrusion in the rim. The brakes hit this protrusion, and suddenly grab, always putting a large part of the breaking strain on a single patch of the tyre.
