Project 500 - The Tubeless Conversion with Maxxis Minion DHFs

If you've read some of the previous installments of Project 500 you'll be aware of the fact that I've swapped out the original Kenda Rogolith tyres with Maxxis Minion DHFs - yes front and rear. And for those of you that are wondering why not have a Minion DHR II on the rear, it was purely because at the time I couldn't actually get my hands on one - that whole global mountain bike component shortage is still a thing and extends to tyres as well. In any case, for those of you that think that the F in the Minion stands for Front (which it may well do but it may also stand for Freeride), you'll actually find plenty of people that ride with a DHR II on the front and perhaps less occasionally a DHF on the rear (more on that at the very end).

Green tape covered the rims on the rear wheel while red tape was on the front. I don't know why that is (other than the fact the rims are different diameters) or even if the tap on the rims is meant to be tubeless as the bike shop was surprised when I told them. But the tape on these rims seal in the air perfectly fine.

Anyway, what I didn't mention in the previous installment was that the 500's rims actually come taped, ready for tubeless. This is despite Merida's website saying that they don't come with tubeless tape, which they technically don't. However this is the third time I've wacked some sealant into a tyre and jumped plonked them onto the base spec Merida Expert TR rims to find that hey seal just fine.

The process of converting a mountain bike to tubeless is generally relatively painless, especially if your rims already come pretaped. It's literally just make sure you also have a tubeless compatible tyre (the Kenda's that came with the bike weren't incidentally), grab some sealant and a tubeless valve - because you obviously don't have a valve once you pull the tube out. And on the subject of tyres, I've never had an issue with a variety of Maxxis folder tyres - they always seem to sit on the rim pretty well with a decent seal, even before you put the sealant in.

Tubeless valves themselves aren't too expensive - I think a base set without any fancy colours will set you back around $25. They can become quite pricy though if you opt for the fancy, branded ones with pretty colours. I opted for the ones that I installed on my other bikes - Dert, which still come in fancy colours for a mere $30 a pair. They also come with spare valves and the lid does double duty to remove or tighten the valves as well. I've not had any issues with these and with them installed on three different mountain bikes, have a plethora of spare valves in case any of them get gummed up by the sealant. Basically, you don't need to spend a lot to get some cool valves that just work.

These Dert tubeless valves add a bit of colour, come with spare valves which can sometimes get blocked up and a neat feature where the lids can be used to loosen or tighten the valves

I've always found that the hardest part of sorting out the whole tubeless tyre thing is to get the tyre to sit on the rim properly. When you use a tube, the tube just pushes the tyre out to where it needs to be, particularly with a folding tyre. This is less of an issue if you happen to have a reasonably high volume air compressor or one of those chamber pumps, which can push so much air out that it brute forces a tyre onto the rim. But if you're just using a standard floor pump and are struggling to get a tyre seated, somtimes just throwing a tube into get it to hold it's shape and then removing said tube can help. After you've got the tyre into the right shape, you can just deflate it, remove the tube and work on getting the tyre to sit on the rim.

You may find through this process of using a standard floor pump to seat the tyre that you get a decent workout and practice your swearing until you here a bit of a loud pop, indicating the tyre is finally sitting on the rim properly. I usually pump the tyre up to about 50 psi just to make sure all of the edges are sitting. You should find that the tyre will actually sit on the rim and hold air even without sealant. There may be a few minor leaks but if your tyre isn't maintaining pressure, I wouldn't recommend adding any sealant until you have that addressed. Incidentally, if you do struggle to get the tyre seated, pulling out sections onto the rim by hand and putting a bit more air can also help.

Once I've got the tyre seated properly, I'll deflate it and pop out a side so I can add sealant. Now, there are some people that will get some of those fancy nozzles that will enable you to add sealant through the tubless valve by removing the valve core and feeding in sealant in through that entry point, thereby maintaining the tyre seal. If you do happen to decide to put sealant through the core, make sure you take all the air out otherwise you may find the valve core rocketing off into some far corner of your garage. I'm actually just too lazy to do all that fiddling and just find it easier to dump the sealant straight into the tyre.

I put glitter in whenever I add sealant to a tyre which is really just an old habit from when sealant didn't always plug a whole effectively.

So I'll actually remove a section of the tyre from the rim instead - about a quarter to a third of the tyre. You should find if you do this that the remaining tyre will actually maintain its contact with the rim, so re-inflating it shouldn't be an issue. At this point, I'll add... nope, not sealant but glitter. Truthfully the order doesn't matter, but I've been adding glitter into my tyre for a long time now. The theory behind it is that sealant is obviously a liquid, and with a bigger hole the sealant will just spray out. But by having glitter in the tyre, it will help to clog the hold and give the sealant more to hold onto as it attempts to seal any puncture. It doesn't always work, but it may help enough to slow down any leak until you've finished your ride.

The amount to add in just depends on the diameter of the rim and the width of the tyre. Most sealants these days will give you an approximate idea of how much should go in along with having a window on the side of the bottle to help you with the measurements. You'll find if you're using a syringe to push sealant into the valve, this will take a number of times to get the amount in. Hence why I just remove the tyre and pour the sealant in - I just find it faster.

Once that's done, it's just a matter of replacing the tyre back onto the rim and pumping the air back in to resit the entire tyre. Again, I'll generally pump the tyre back up to 50psi, not only to make sure the tyre is seated properly, but to also create enough pressure that causes the sealant into any potential leaks. Incidentally, if it's a brand new tyre it may help to not put your rim back on your bike just yet as it can be helpful to spin the tyre and twist it in a variety of directions while it's spinning to give the sealant a chance to get into every nook and cranny and seal up any potential air leaks. Leave the tyre overnight, spinning occasionally to distribute the sealant - and that's that.

On a recent ride and with 30psi in the rear I managed to get a puncture that was too large for the sealant to permanently close up. It managed to slow the air leak long enough for me not to notice too much during the last 3km of the ride, however I could see it wasn't going to stay inflated on a ride the following day.

Now, one of the benefits that people prescribe to about being tubeless is that you can run lower tyre pressures. I always caution people about this line of thinking simply because if the tyre gets caught between the rock and the rim, it can still get cut. The photo above shows a recent ride where the sealant was unable to patch the whole that likely appeared after a drop or jump (I'm not sure which). And that was with me running 30psi in that particular tyre. So being tubeless doesn't necessarily mean you should run lower pressures.

So why bother with tubeless at all? Well, to be honest I didn't notice that I'd had the damage to the tyre until someone pointed it out to me at the car (that someone incidentally was a rider in our group who was also tubeless and damaged his tyre so badly that the sealant came spraying out of his tyre and up his back). On checking the tyre I'd definitely lost some air and realised why I'd felt some squirming towards the end of the ride. But whereas a tube would have instantly deflated, being tubeless allowed me to continue the ride for a few kilometers without even noticing.

Anyway, there's a quick summary on what it takes to do a tubeless conversion, along with why I do recommend people do it, even if you can't really run much lower pressures than with tubes. And truth be told, while I could probably put a plug in the hole, my rear tyre is probably due to be replaced anyway.

One thing about getting a large enough hole with a tubeless tyre is that the sealant can spray onto all sorts of places, leaving you with a bit of a mess to clean.

Something worth mentioning about tubeless is that if you do get a large enough hole, you'll find that sealant can spray out like a fountain onto all sorts of areas. Basically, you'll end up with latex everywhere, which might be fine if you're into that sort of thing but can be a bit of a pain to clean up. It's not enough of an issue for me to not want to go tubeless - I've only had a fountain go up my back once, but don't be surprised if it does happen!

And finally, I mentioned that I'd briefly touch on what it's like to have a Minion DHF as a rear mountain bike tyre. For those that are unfamiliar with the DHF's handling traits, it's a fairly legendary cornering tyre with a particularly unique characteristic - a vague spot when transitioning from the centre knobs to the cornering knobs due to a channel separating the two. That channel allows the side knobs to really dig into a corner. However at speed, sometimes there's a split second where a tyre may not grip, especially if you're not leaning the bike over aggressively.

On the 500 with its mullet set up and short chain stays, that particular trait can lead to the back end briefly snapping around the corner as grips is momentarily transferred from the centre to the side. Basically, it feels like you're fishtailing around the corner - it's just often expected. I think this is also exacerbated by the weight of the ebike would, requiring the rear to handle even more cornering forces than it would have to handle on an analogue bike.

After just over six months of riding you can see that the side knobs of the DHF are looking a bit word, tired and stretched. The extra weight of being mounted on an e-bike probably doesn't help.

What this amounts to is an e-bike that despite its heft, has the ability to weave through some very tight corners - just sometimes in a rather uncontrolled fashion. I've gotten used to expecting the rear end to momentarily break away now - sometimes I do it deliberately actually to get around a particularly tight corner at speed by shifting my weight well forward. However if you like riding at speed but aren't the most confident when it comes to cornering, a DHF on the rear is probably not something that will help with making you braver at cornering. I'll let you know what I end up replacing the rear tyre with at some point in the near future. Until next time!