Trials Tyres

[trapezeartist]

So here's a naive question that has been niggling away in my head for a while. Why are trials tyres the way they are?

Is there a rule somewhere that bans MX or enduro tyres? Or has years of experience led to conventional trials tyres being the best for the job? I occasionally watch an X-Trial video and wonder why no-one has tried a slick tyre.

[eddie1]

It's in here somewhere.

[gazzaecowarrior]

I think it helps keep the sport accessible and competitive as pretty much everybody is riding on the same tyres. Trials is one of the cheapest motorsports and having everyone riding on the same tyres means that ability rather than expenditure will give all riders a fairer and more equal role of the dice.

[trapezeartist]

4 hours ago, eddie1 said:

It's in here somewhere.

Shows how carefully I read the regs! Anyway, that clearly settles my question. Thanks.

[trapezeartist]

1 hour ago, gazzaecowarrior said:

I think it helps keep the sport accessible and competitive as pretty much everybody is riding on the same tyres. Trials is one of the cheapest motorsports and having everyone riding on the same tyres means that ability rather than expenditure will give all riders a fairer and more equal role of the dice.

Absolutely true. Nearly every other form of motor sport is dominated by tyres, and almost invariably the way to go better is to spend more on tyres. When I came to trials a few years ago it was clear that it was going to be a cheap sport. In my head I budgeted for a rear tyre every year and a front tyre every two years. I've just bought the third rear in five years and I've never yet bought a front.

[tony27]

I doubt MX tyres will fit most trials swingarms & aren't tubeless like trials specific tyres, in most trials situations they won't grip as well either due to shape & sidewall stiffness

I find it interesting how in the regs it says nominal maximum size of 100/100, at least 1 of the modern tyres is labeled 120/100 on the sidewall which I'm guessing has to be with how the manufacturers measure their tyres, different brands of MX tyres vary hugely in width, a 100/90 is the same width as a 120/90 as 1 is measured across the case & the other across the knobs

[bullylover]

Over here in Australia it is in the Motorcycling Australia rules for Trials it states that all tyres apart from Sidecar chair tyres must be a Trials Universal pattern. No sizes are specified though.

[Intotrials]

14 hours ago, tony27 said:

I doubt MX tyres will fit most trials swingarms & aren't tubeless like trials specific tyres, in most trials situations they won't grip as well either due to shape & sidewall stiffness

I find it interesting how in the regs it says nominal maximum size of 100/100, at least 1 of the modern tyres is labeled 120/100 on the sidewall which I'm guessing has to be with how the manufacturers measure their tyres, different brands of MX tyres vary hugely in width, a 100/90 is the same width as a 120/90 as 1 is measured across the case & the other across the knobs

MX tyres are rubbish on rocks they are way too stiff and also put down less tread contact area, basically a trial tyre moulds around obstacles where a mx tyre just bounces off. If I put a trials tyre on my enduro bike it transforms it especially when doing anything slow and technical. Trials tyres are so much better for slow technical stuff but not as good at high speed or high impact.  

Edited November 7, 2022 by Intotrials

[faussy]

Its an interesting point. I dont think the tread pattern has changed from the 60s, maybe even 50s. All thats changed is the number of plys and compound. I wonder what the ideal tread pattern would be if we werent held to the rulebook (which i think is a good thing btw). There would definitely be a mud vs dry weather tyre for starters. And you point about slicks for indoor. Surely if it was advantageous someone would has used a very very well worn tyre bordering on a slick that still kept to the rule book. I guess its a competition between contact area and grip against 90 degree angles which a treaded tyre will do better over a slick

[turbofurball]

I would guess the slightly knobbled pattern of bicycle trials tyres would be optimum for indoor stuff

[rabie]

developemnt wise trial tyres have "always" been imperial - ie 400x18 (or even 350x18 for very old bikes), but when Michelin launched the X-light they made it in a metric size

when maxxis launched their "trial ish" tyre (with the first KTM Free rise, about 2014 ish) it has the same trials style pattern but the block spacing is wider and thus not trials rules compliant (depends upon how hot the organiser is)

the issue that many will go into is how the diffrent brands perfom for the the terrain/weather the riders will encounter, ie IRC is very popular here in the wet south in the winter where we ride predominatly mud, while Dunlop with its stiff sidewalls is almost unsealable (due to its lack of performance in the winter) but does sell better up north as it performs well on rocks. I don't have sales data to hand but Michelin (with the X11 and the X-light) appear to dominate the market. if one is doing other things beyond closed course trials (ie roadwork, LDTs, enduros with tyre restrictions, etc) then Pirellli's MT43 and others (Vee Rubber, etc) become more usefull as they don't wear out so quickly.

[lineaway]

Dunlop TL01 will be out in 2023. Looks to compare to the X11.