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There are plenty of articles out there about which eMTB to buy, which system to go for, and what the best components are, but what is it like to have one of these things out in the wild? In this feature we detail what it's like to own and maintain an eMTB, rather than putting in enough miles for a review, and then shipping it back to the manufacturer. This piece isn't to tell you which bike to buy, or what kit is best, but hopefully to give you a few things to consider if you're in the market for an eMTB.
Last November, I picked up a Cube Stereo 160 Hybrid, which has been my personal bike ever since. I have put in about 1,500km on it. About 70 rides, varying from short runs to the shops, to back-country loops in the mountains where I live. During that time, I have played with some of the components and tweaked, fiddled, and fussed with the setup. Here's what I learned:Invest in the Motor and Battery
If you're about to lay down cash for an eMTB, don't be sucked in by the main components. Get straight to the powertrain. This isn't like choosing between a RockShox Lyrik and a Fox 36, or Shimano XTR and SRAM X01. The motor and battery are going to colour the rest of your time on the bike. You can't switch the motor over later and a new battery can cost around the 700 Euro mark. Get a good system and you'll barely think about it, but if you get a bad system you will find yourself cursing it, struggling up the technical sections, and running out of battery all too soon. A 500W/hour battery should be one of the first things to look for. Having been forced off my customary Bosch system for work for a week, it was surprising how switching to a system that doesn't work as well dominated the experience.Tyres
eMTBs look to be a natural home for big tyres. Almost every brand is spec'ing their eMTBs with 2.6" and up. Having tried a few tyre sizes, I'm confident in saying that you're definitely going to want bigger ones—the increased contact patch helps almost everywhere. The question is how big? There are two problems with "Plus" tyres: first, the casings. When you're riding a 50lb bike, support from the sidewall becomes more crucial than ever, yet most of the major Plus tyre suppliers don't offer aggressive tread patterns with anything stronger than an intermediate casing. This means you'll have very little support from the sidewall when you're trying to lift or pop the bike. Instead, the tyre deforms and feels vague. And, there's the usual issue of how fragile Plus tyres tend to be. If you are an aggressive rider on rough terrain, you are going to find them deflated in no time at all.
An eMTB will accelerate tyre wear too, so you are going to find yourself running through tyres faster than you might expect. A Maxxis Rekon EXO 120TPI in 2.8 retails for around 150 Euros (you can find them for 90 Euros a tyre on certain online retailers). How do you feel about the prospect of running through one or two in a month? If you opt for DH tyres, you're faced with adding a kilo to the bike's rotational mass, which still becomes is a big issue with these bikes and will reduce your range noticeably. Right now, the only tyres on the market that seem to tick the size, weight, and strength boxes are the Maxxis WT 2.5s—but at 60 Euros a pop, they are still a pricey proposition. Schwalbe Magic Mary 2.35" bike park tyres, which are strong and cheap, but they come up smaller than I would personally prefer to run.Service
One of the biggest differences with an eMTB and a mountain bike is going to be your relationship with wrenching on it. Most serious mountain bikers are used to fixing their own bikes, and shipping them off for only the most delicate or complicated of jobs. This is not the case with the powertrain on eMTBs. A big part of this is down to the legality of these bikes. If the maker made it easy for you to pop the cover off and tweak it, then it would be all too easy to hack the motor to exceed the legal limit of 25km/h top speed and 250W power output (for instance: Bosch's 750W motor uses the same hardware as the 250W moto, only it's software differentiates the two). In other words, you are going to need to get to know your local bike shop a lot better. This is somewhat of a double-edged sword. While most people like the idea of supporting a local bike shop, they are running a business, so you are going to need to give them your hard-earned in return for fixing your kit.Replacement Parts
Replacement parts are another practical issue. Earlier this year, I smashed my bashguard on a rock, which meant the chain wouldn't complete one rotation of the sprocket without jamming behind it. It is one of the few things on the Bosch system that you can fix at home relatively easily. The parts are fairly cheap—the sprockets are 15 Euros and the bashguards are around 30. However, none of the local shops had the parts in stock, even the supposed eMTB specialists. This is definitely a concern. If I'm going to take my bike into a shop, then I expect them to have the basics to hand.
In the end, the internet solved the issue, but as soon as the parts arrived, it became clear that a 30-Euro special Bosch tool was needed to assemble them (a familiar story for most MTB systems these days). The repair itself took 10 minutes and the tool proved worthwhile for a couple of reasons. Firstly, a huge amount of dirt builds up around the sprocket, so whipping it all off and cleaning it fairly regularly is well-worth doing. Secondly, it meant I could experiment with different sprockets. Dropping from a 16t to a 14t sprocket made a big difference to the bike—it turned out that I was rarely using the 11-rooth end of the cassette, because the motor's assistance tops out at 25km/h. lower 14t drive sprocket moved my most-used gears towards the center of the cassette and reserved the big sprockets for climbing. Where to Spend, Where to Save
If you're buying parts for an eMTB, the calculations on where to invest your cash are different from a regular mountain bike. Good hubs are an absolute must. I have seen more than a few eMTBs with lunched freehubs as the extra torque tends to tear through them. I have been running DT's star ratchet system for nearly all of my 1,500km on the Cube and it seems to be holding up well so far. Conversely, with the rims: strong, wide, and cheap are the key ideas. You'd have to be either drunk or rich to consider mounting an Enve rim to an eBike. Ideally, you'd want a tough rim that is semi-disposable, somewhere in the 30–40mm-width range. (I have snapped four rims on my local DH track on the Cube.)
Cranks are another area to avoid investing in too heavily. Currently, many eMTBs come with FSA cranks, which are pretty much perfect, except they don't come shorter than 170mm. I have found that I am smashing my cranks on eBikes much more often than on my mountain bikes—mainly down to the steeper, more technical climbs that are possible, where you don't always have the luxury of timing your pedal strokes. At 40 Euros a set, I don't feel guilty about smashing FSA crank arms. If they last six months I'm happy. Miranda also make cranks at the same price point and they offer more options for both finish and length. Some of the recently-launched eMTBs come with some lovely-looking Race Face cranks. Don't get me wrong, I highly rate their products, but Race Face cranks can rarely be found at 40 Euros a pop. It's also worth playing with crank length - 175mm cranks don't really have any place on a modern mountain bike, in my opinion, and on an eMTB you can go even shorter. I have heard tell of German journalists running cranks as short as 135mm, but I'd start with 165mm first.
Same goes for drivetrain components. There is no point to buying a lightweight cassette or chain. You will pull them apart in no time at all. The SRAM's EX1 cassette is good, but at 450 Euros, it is certainly an investment and a half. After 1,500km, however, mine is still going strong, where normally I would expect to be on my third regular cassette. You'll need to choose whether to go for the big one-off purchase or more frequent smaller purchases. SRAM's one-step gear shift is frustrating at first, you miss the consistent spread, but it does seem to help increase the life of the chain and cassette, as it helps prevent you from putting the torque through the chain at odd angles when you shift multiple gears. Finally, you're going to want the biggest brakes you can find, ideally paired with 200mm rotors. When the bike weighs more than 20kg, saving 15g by dropping to 180mm rotors is foolish. A general rule is to approach your eMTB components choices as you would a DH bike, as it is going to receive more abuse than a regular mountain bike.Suspension
I will admit that my personal experience is a little off the back with some of the newer eMTB-specific options. The first thing I have found is that stock mountain bike suspension tends to be under-damped. Up front, my Cube has a standard 160mm Fox FIT4 Factory 36, which is widely rated as one of the best forks on the market, but I have it pushed to the end of its tuning range. I weigh 75–80kg (depending on the time of year) and when I was just working with air pressure, I had over 100psi in the fork to try and stop it from diving in steep compressions. Adding air tokens helped, but I am currently at four orange tokens, which feels like a lot for someone of my weight and ability (I believe it is about the same as Richie Rude runs for the EWS). I have since backed the air pressure down to 85psi and added on as much compression damping as I could (I feel the last click makes the fork too harsh), but it is still not quite there. My brief experience with the eMTB-specific Fox 36 has been positive, but I only have a few days on unfamiliar trails with it, nor have I spent much time on a Rockshox eMTB fork yet.
Out the back, I think the answer is simple: coil shock. For this kind of bike, where the weight is less critical, it is just a better way to go. The Fox X2 coil shock I am running has the advantage of high and low-speed compression adjustments, which means I can tune it to my personal preferences (this may not be the best solution for everyone). If anything, I would like a re-tuned compression lever, so that I can have modes with more damping for descending and general riding, then a completely open mode for technical climbing where I want every little bit of traction possible. Quite the opposite from present shocks.Silencing Rattles
Rattles are a big problem with the current Bosch system out in the real world. The battery mount is a cradle the bike manufacturer fits onto the frame, and most companies leave it at that. After a while, the battery starts to work loose on the trail and it make an unpleasant noise, especially when going fast. When Kieran was reviewing the Haibike we noticed that they had placed some foam underneath, which silenced the rattle. A quick scour of Amazon turned up adhesive foam that is mostly used by kayakers. At £10–£20 a roll it's pretty cheap, and a small piece under the battery silences it wonderfully (at the expense of needing to force the battery in slightly once it is in place). The next generation of eMTBS seem to have integrated batteries, so maybe this is a moot point, but when eMTBs cost as much as they do, it seems a fairly glaring oversight—especially one so easily solved.