MI:TECH Epsilon – Mid Term I (focus on PINION P1.18): by c_g

OK, folks plenty of trail miles under my belt with the MI:TECH Epsilon and just about time for a closer look at this 120 mm full suspension 29″er busting with interesting technologies (Unified rear triangle frame, PINION P1.18 gearbox and GATES belt). For the bike´s intro go here.

Initially we chose to introduce the MI:TECH Epsilon by its various technologies, but we were informed by the men behind the bike, that it can only be understood as a complete concept. According to Jürgen Militzer of MI:TECH „The Epsilon is a bike specifically designed with internal gearing (PINION or ROHLOFF) and the GATES belt drive in mind – only in this configuration will it rise to its full potential.“

In our effort to bring to you the full picture and not stick in superficial information only, we decided to split this Mid-Term article into two pieces – this one focusing on the PINION P1.18 gearbox and part II going into depth about the Epsilon´s suspension action and ride feel. So now directly to my experiences with the PINION P1.18:
First the most important facts:

1: Those consistent 18 gearing steps of 11.5% each are plain awesome! If you get used to them, you are running a high risk of getting being spoiled by such perfect gearing and it is getting hard to return to any other drive train system. I have been mostly on 1 x10 for the last few months and all of a sudden being confronted with those 18 evenly spaced steps, I felt overwhelmed. Also, in the beginning, after shifting into a faster gear, I found myself wondering if it had shifted at all, only because the steps were so close. So, initially the steps actually felt too close, but I soon learned to appreciate them big time. ? If you are a perfectionist with the highest expectations in your gearing steps, look no further. The P1.18 is the master of its class!

2: The 636% in gearing range needs to be ridden to be believed! In times of 2×10 and 1×11 where the gearing range slowly but surely gets more narrow – and where even most standard 3×10 drive trains don´t offer everything we 29″er riders wish for – it is pure luxury to deal with the wide range of the P1.18. Even on the steepest uphill pitches I have never run out of gears and coming from 1×10 I often felt under-challenged because I could always drop another gear or two. On the other end of the spectrum, I also never really needed to have higher gears for those long and fast forest road downhills.

(Of course this only applies if the ratio of front and rear sprocket is chosen correctly. PINION themselves recommend a ratio of 1:0,89 for 26“ bikes which translated to 29″er would be something like 1:1, but it is important to note that PINION explicitly opens up almost any ratio one would want to ride.)

3: The fully sealed gearbox works absolutely unimpressed by the environment you´re riding in. On several rides this winter my riding buddies with standard drive trains found themselves limited to a few (if not only one) usable gear because their chain rings and cassettes were frozen solid after one or two hours of riding in our wet and freezing conditions. This quality is in no way specific to the PINION, but under such adverse riding conditions you are quickly reminded, that standard external shifting drive trains, just are not all that foolproof.
I admit this test says very little about long term durability (no 1-2 month test can tell that story), but so far I can easily attest the PINION P 1.18 system having flawless durability in the kind of conditions I have been riding in.

4: The twisting shifter itself is ergonomic and grippy – no complaints here either.


… and now for the little things and peculiarities you only notice when given the opportunity the time to ride the system in real world conditions:
– The PINION P1.18 is a internal gearing system that is positioned right between the incoming force (cranks) and the outgoing force (front sprocket or chain ring). Consequently both are operating independently of one another (e.g when pedaling backward, the sprocket simply remains unmoved).

– The free stroke of the PINION P1.18 is unusually big. The PINION engineers have gone to great lengths for getting all different parameters of durability, weight, and engagement (and many more) to their optimum and openly communicate that the P1.18 needed to take this slight compromise to keep all other aspects at the highest possible levels. But as it is, even someone like me, who is not too picky about instant engagement, does notice the long way the cranks sometimes rotates before engagement (which by the way is bombproof and secure) is happening. Especially when riding in technical terrain I felt it actually affecting my ride. To reduce this effect to a minimum, PINION offers a special rear hub in cooperation with ACROS (essentially a single speed hub with a very fast engagement).

– The P1.18 is essentially two gearing mechanisms (one 3-step and one 6-step unit) put in line and therefore shifting forces and performance is not 100% homogeneous throughout the range. There are two gear steps (6/7 and 12/13) where shifting is only possible when the cranks are completely unloaded. The reason for this is that in those steps the constellation is rearranged.

Consequently when riding you can change gears even with some pressure in all but those two steps. If you are used to the homogeneous shifting feel under pressure of an external drive train, the PINION will take some getting used to. Early in testing I found myself getting stuck in those specific gears, only because I hadn’t unloaded the system completely. Once I had adjusted, this happened way less. (These inhomogeneous jumps are inherent to any internal gearing – ROHLOFF does have one such step as well – only with PINION there are two and as such it is more noticeable.)

– … on the other hand one can change the full range of gears even when not pedaling – a huge benefit once you realize the potential (e.g when technical ups and downs are frequently switching or when you are starting after a stop.)… but this only works when unloaded completely again.

– When unloaded shifting forces are identical up and down, but when partially loaded shifting into slower gears becomes much harder to a point where it is virtually impossible. When going to faster gears the rotating forces on the shifter remain low regardless of the pedal pressure.

– The weight of the PINION gearbox (2.7 kg or 5.95 lbs) to me is noticeable in different ways. For once it adds to the complete bike´s weight and adds up to a rig that will never earn the title „lightweight“ or “snappy”, but interestingly this weight is not really negative to the „ride“ due to its very low center if gravity and touring character of the Epsilon. But when trying to lift the front wheel (for a wheelie or manual), I noticed the huge effort involved. I am not saying this is purely the PINION´s fault, after all the Epsilon has a long stretched geometry and long chain stays, but it surely plays a role here. Other bikes with Pinion gearboxes, which we may get to ride in the future may prove me wrong.

I am not a big jumper, so I better not comment much if or how it affects the bikes handling in the air – where I rode it, it never showed negatively.

–> Mid-Term Summary: So far the PINION P1.18 is a piece of equipment with loads of sunshine, but a bit of shadow, too. For now I feel it follows suit with the other high end internal gearing system – the ROHLOFF Speedhub – in that it is perfectly suited for touring and adventure riding and any use, where reliability is key. The small gearing steps, consistent performance under any circumstances, the wide gearing range and the simplicity of only one shifting lever is absolutely fantastic and far superior to any standard external drive train I know.

For the ambitious trail rider with a heart for technical riding, I do see a few drawbacks, though. One was the weight which overall was less noticeable when merely „riding“, but more so, when „playing“ with the bike … and the other were those little peculiarities in shifting performance, that even after weeks of riding still were distracting my attention. If I were looking for a reliable bike for my next adventure trip and needed low service requirements, I´d definitely consider the PINION, for my current 1-4 hour rides and occasional alpine adventures, not so much.

So much for my closer look at the PINION P1.18 gearbox when used in a rather average MTB environment. In a couple of days you will find the riding impressions of the MI:TECH Epsilon, one of the very few existing URT bikes on the 29″er market .. so, stay tuned.