Wish: Knobbly 36er

Muni on a 36er is just awesome. Yesterday I was out riding XC trails with a friend. I had my UDC 36er, he had a 26" muni. My 36er absolutely flew over the trails, including bits of flattish single track - it was awesome. If you keep your wits about you and plan for the trail ahead the huge wheel rolls happily over everything in your path, at really high speed.

For the majority of riding, my Qu-Ax / Wheel TA / slick tyre works fine - it has a big contact patch so it’s fairly grippy. But I wish I could get a 36er tyre with knobbles on.

We were looking at descending a steep hill. My friend’s 26" (which he’s not yet used to) slipped in the mud, and he UPDed. I was confident that with the high speed possible on my 36" I should be able to successfully spin out the bank, despite its steepness and slippery mud surface. And I was right, I descended the hill no problem…

Unfortunately, disaster struck on the flat. With the speed I’d acquired down the hill I carried on rolling through the singletrack. Unfortunately, I hit a particularly slippy section and the slick tyre just stepped sideways underneath me. Suddenly I was stepping off sideways, kinking my ankle painfully outwards underneath my weight as I fell from a height, at speed. Ouch.

The result was a nasty sprain - no worse, fortunately. I was glad to have been wearing boots with ankle support (they do have some safety disadvantages but I always figure that for me these are outweighed by the extra protection). After lying there recovering, I found that I had landed in a patch of stinging nettles - oh dear. Fortunately my long sleeved top protected me - mostly… I’ll be unable to ride for a while, am taking ibuprofen and am wearing an ankle support (and icing / elevating / resting the injury). Still, it’s tedious being injured - as always.

Anyhow the bottom line is that coker muni is great fun and I’ll continue to do it. However, I’m going to have to be wary of slippery / steep sections in future. Obviously falling from the height and speed of a Coker is never going to be good, but in this case I really really wished I could have had a proper knobby tyre (not like the standard Coker tyre - real knobs) to give me that little bit of extra grip. I guess I’ll just have to cross my fingers and hope enough people realise the utter awesomeness of coker muni-ing for a knobbly tyre to be put into production!

sorry to threadjack, but the top 3 threads in RSU are all about coker tyres! wow!

back on topic.

that sounds like it could be A LOT of fun with a grippy tyre, although i imagine it would weigh A LOT.

Something like a 36" Kenda Klaw would be extremely cool :smiley:
But coker muni is such a niche market I doubt it would ever be worth anybody making anything like that - they’d have to sell them for a ridiculously high price to make any money. The 36" tyres we have now are already expensive enough.
A decent XC tyre was one of the requests when the bloke from Coker was on the forum asking about what people wanted from a new Coker unicycle, but I fear it’ll never happen :frowning:


Absolutely. Wouldn’t need to be any fatter, or knobblier, just have better grip than the existing tyres.

It’s a shame that it’s a niche market, really - it’s such amazing fun, even though it doesn’t seem like it should work :slight_smile:

Indeed, I also fear that a 36" knobbly is unlikely for the time being, but I can dream :wink: If such a tyre were available I could almost completely abandon my 29er, and have a truly go-anywhere machine.

I know the standard Coker tyre has small knobblies but I’m not really sure they do much for offroad grip. Has anyone on here had comparative experience of both 36" tyres for offroad? In the dry I doubt it’s much different, but in the wet…

I’ve seen suggestions that the Qu-Ax / Wheel TA Slick is thick enough that it could successully have knobblies cut into the tread by an enterprising cyclist, using a Big Knife of some kind. The little existing tread contains quite deep grooves, so it seems like this should be possible without going all the way through the rubber!. If the Wheel TA tyre weren’t so expensive I’d be tempted to try this myself…

What would be really really nice is if somebody with some budget / experience were to make a custom job here. Some smalltime builder could perhaps offer munified 36" tyres with cut knobblies - for a fee on top of the initial cost, of course! I’d certainly be very interested in such a tyre, especially with some sort of hybrid on road / offroad tread pattern. Could be very great for muni-ing coker-nuts.

That’s because cokers are great :slight_smile:

You can get a 36" surprisingly light with some effort - Ken Looi has an incredibly lightweight machine (although perhaps not stiff enough for offroad?). However, I don’t really find the weight is a problem. Mounting in a confined space or on lumpy ground can be tricky, but seems to be doable with persistent practice. Once that huge wheel is spinning, almost nothing seems able to stop it. A well-built airfoil wheel is pretty strong and the large diameter, fat tyre and inertia make rolling over bumps easy. It’s quite surprising how the large wheel likes the rough stuff.

As I found, it’s also quite practical to spin fast down steep hills. The downside is you need to get rid of that speed at the bottom - preferably without twisted ankles!

In fact, since the tyre has a big footprint, grip should be pretty good most of the time. The only major grip problems I’ve had have been on wet and muddy surfaces. I’m not sure I fancy riding it on ice / snow, either - but I’ll probably try this for giggles :slight_smile:

The knobbly coker tyre is pretty good off-road. I’ve used it in slippery conditions and it holds up fine- I think partly because of it’s large surface area. I also run slightly lower pressure with the tubeless set-up so that probably helps as well.

The big diameter is good at rolling over stuff- kind of like having suspension to soak up the bumps- you don’t notice the small stuff.

I think it is important to get the weight down especially on the wheel- it aids maneuvarability and let’s you flick it around under you in tricky terrain.


Why doesn’t someone stud a coker tire? I’ve seen muni wheels with it done so there is nothing stopping anyone from with modifying a coker tire for it (other than price of the tire). Of course, it wouldn’t be quite as well suited for road riding it would sure work well for off road and snow/ice. Maybe if you were to just stud the sides it would work fine on road as well.

Something such as: Studded Gazz but with significantly less drastic lengths.

I wish for a lightweight version of the coker tyre. I mean one made like a road bike tyre, still 36 x 2 1/4", but light. Both the original Coker and Wheel TA tyres weigh a ton. A lighter tyre would make for a much more nimble, quick to accelerate and generally all round better 36er.

I’m seriously considering cutting some grooves in my TA tyre to try to avoid wipe-outs on grass/mud. First try will be with a lino cutter, and if it works I’ll let people know. Real tyre cutters use a heated blade, so it might not work well, but it’s worth a try I think. I’ll try cutting a shallow groove first to see if it cuts it nicely.

With my limited cokering experience so far, it still feels incredibly heavy and cumbersome - my 26x3 muni feels like a featherweight racer after a few rides on the coker. The coker is slightly quicker over a given xc route than the 26, but at the moment seems to take loads more energy to ride - hopefully that’ll change as I get more used to it.


Please let us know how you get on - pics would be nice! Maybe you could copy some offroad / hybrid tyre for inspiration as to pattern? Or just try to write your name in the tread :slight_smile:

I think it will - I suspect you’ll like it. It’s very important to be smooth and flowing when doing anything with a coker - if you can keep up the momentum you can fly along. Remounting is where I currently lose most time, but that can be addressed with a static mount to avoid too much rolling over the bumps.

you could try to do a track spike idea. have the holes that you just screw in regular track spikes. might cost a lot, but the spikes would be better than just regular screws.

I’ve ridden my Coker tire off-road in snow and ice, on hills, in the dark no less. I just dropped the pressure way down, and it was great.

WHOA TEST IT ON AN OLD (or new if you don’t have an old one) and smaller tire first

I’m not an idiot (or willing to ruin an almost new £60 tyre) :wink:
I’ll try a small shallow cut first and if that doesn’t cut nicely I’ll give up - if it works well I’ll cut some more. A coker tyre apparently performs pretty well off-road, so the only reason I’m thinking of doing this is because the 36er I bought (from DarkTom) had a TA road tyre fitted, which was almost new. I don’t want to spend £60 on a new Coker tyre (if they’re even available) until the TA one wears out, but I do mostly xc riding so a bit more grip would be nice. I don’t expect my cut TA tyre to be better than a Coker one (although the rubber is thicker so it might last a bit longer). I’m not planning on cutting loads of rubber away to make a proper nobbly tread, just cutting some grooves across the tread to make it a bit less likely to slip on wet grassy hills.

I wonder how well it would be possible to glue (with some sort of industrial adhesive and a suitable clamping device) the tread portion of a bike tyre to the outside of a 36" TA tyre :sunglasses: . Two Kenda Klaws or similar would be enough to cover a whole 36" tyre if it could be stuck securely enough. Clearance might me a bit tight in a normal coker frame though.


Very possible I would have thought, but I would wait until you’ve got a tyre carcass thats worn down pretty far, so the added rubber replaces worn tread and therefore hasn’t got the weight and clearance issues that sticking half an inch of tread on the outside of a new tyre would have.

Might be worth e-mailing Roger and seeing if he has an old coker tyre carcass worn through that could be used as a base? I would be really happy to try this if I had a tyre I could use. As well as sticking the tread on, you could try riveting the ends down to stop it peeling back…


I wouldn’t think the clearance would be much different (the tread’s not THAT thick even on a new tyre), but a worn one would be a good base because it would have a nice flat surface to glue to. And it would be cheaper of course.

To do a really good job you’d need a hoop-shaped thing to fit inside the tyre and a band to clamp round the outside to keep the tread pressed onto the carcass while it set. Once the jig had been made (and assuming it worked well) it should be easy to repeat it on another tyre. Some sort of spikey rubber matting might be cheaper than cutting up a couple of bike tyres, but the compound would probably be less than ideal for a tyre.
Sounds like a good idea in theory. Bound to end up quite heavy though.


Why would you stick 2 Kenda Claws ON an existing Coker tire? If you cut the tires and make a 36" tire out of it by welding or glueing (or a combination) together that would work, I know of a japanese rider who glued 2 24" tires together to make a 36" racing tire, even though a MUni tire would have to withstand more abuse, I believe it’s possible.

That would be excellent if it works - I suppose you’d have to stick a small section of something over the inside of each joint so it would be flush on the outside. The strength of the bead is what would worry me (it would be likely to stretch and blow off the rim, even if it didn’t break while fitting it to the rim in the first place) - although at low xc pressures it may not matter so much - that’s why I was thinking of using an existing tyre carcass. Do you know who that Japanese rider was? Is it possible to contact him and find out how he joined them?
That sounds an extremely tempting idea… if it worked, it would be a nice xc treaded tyre for not much more than half the price of a normal coker tyre (plus a bit of effort). It would be way lighter as well if done with xc bike tyres :sunglasses:
I might give it a go with a couple of really cheap mountain bike tyres and see what happens - nothing to lose really as long as I ride carefully until it’s proved to be strong enough.


This might be a bit wacky, but a kevlar bead tyre is essentially a tyre with a posh bit of string round it right? When you’re putting together two tyres to make a 36, you’ve got a bit of tyre spare. Would it be possible to cut back the tyre further than you cut the bead, so you’ve got a bit hanging out, then tie the two beads together using a knot.

Downside is that the cheapest kevlar tyre I can find is a tenner.


I like the idea of sticking tread to the outside of a worn tyre. You wouldn’t need to stick the sidewalls / bead on there, either. Given the Coker tyre isn’t as heavy as the TA you could probably get an XC tyre that wasn’t that much heavier than your existing tyre…

The resulting tyre would hopefully run well and also look amazingly cool!

I’ve got less clue as to how good sticking together two tyres would be, although the idea does appeal in terms of weight etc if it could work!