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it's not surprising to me that the bosch mid-drives are failing, they're typically placed at an angle that catches all the run off from every tube at the lowest
by serf 2y ago
it's not surprising to me that the bosch mid-drives are failing, they're typically placed at an angle that catches all the run off from every tube at the lowest point on the bike (except on recumbents), and the controller is (usually) integrated.
mid-drives are great, the gear advantage rocks; the bosch units suck but unfortunately they had so much industry sway that a lot of ebike frames are coming out built around the unit -- which is absolutely unlike any other unit out there aside from vague similarities to the bafang units in the same range -- so it forces replacement with the same garbage, or a total re-engineer of the gear train; a big pain.
one thing to be said about the bosch unit : it looks sleek and it integrates well. This is likely a lot of the reason behind the mass adoption, aside from Bosch's presence itself.
- gjadi 2y agoMy local bike shop said they are all in Bosch because they had better reliability and less issues with their support compared to other companies and because of the commitment to long term spare parts availability.
- ornornor 2y ago> long term spare parts availability. The article says that you can’t get spares, any service requires sending to the factory for repair?
- dgacmu 2y agoThe gear advantage of a mid-drive rocks but I was quite surprised that I chewed through a rear cassette in under a year / about 1k miles -- a 250W motor + heavy cargo bike + kid passenger + a large and pretty strong rider exert an awful lot of force. And with the assist, I almost never use the larger cogs, so all the wear gets concentrated. (This compares to many, many thousand miles on my road bike.) Still love the thing, though.
- wyre 2y agoI have a friend in your same scenario. I’ve never thought to ask how quickly he goes through cassettes on that bike.
- dgacmu 2y agoI think the follow-on post above about making sure to be better about maintaining the chain is part of it. I'm a little lazy with my road bike chain because I mostly only ride it in good weather, and I carried the same attitude to the e-bike, which gets a lot more stress per mile and I'm more likely to ride in rain. I'm not hot waxing it, though it's tempting, but I do wipe it down and apply T-9 much more regularly now. We'll see -- I'm 400 miles into the new chain and cassette...
- germinalphrase 2y agoWould an internally geared hub solve for this type of wear?
- analog31 2y agoIGH's are not all that rugged. Most have a published requirement for a minimum ratio between the chainring and cog, that translates into an approximate torque limit. I love my old Sturmey Archer AW hubs, but I'm not sure I'd recommend one for the aforementioned use case.
- wffurr 2y agoShimano E5000 is an IGH rated for e bikes.
- hagbard_c 2y agoSeeing how as I regularly managed to break the drive cross in my 3-speed SA hub just by pushing the thing real hard under pedal power alone - this is 40 years ago - I don't think they're particularly strong. I fixed my bike by myself so all this cost me was a new drive cross but still, it shouldn't break in the first place.
- fragmede 2y agoI think material science minute might have advanced over 4 decades.
- hagbard_c 2y agoThe cross is made of a fairly hard type of steel. They knew how to make that 40 years ago so I don't think there is any noticeable difference. If anything I suspect the older gear hubs were built stronger than the current ones.
- xcskier56 2y agoMaintain your chain! I chewed through a nice cassette on my mtb quickly by not watching my chain and replacing it when worn. A worn chain will dramatically increase cassette wear. I only replaced it yearly and should have probably done twice per year. Since then, I switched to hot waxing my chains and have now gone a year with the same chain reading as almost new. (Actually use 2 chains but both are barely worn) There’s a great site called zero friction cycling that details all of this. The key that they opened my eyes to was looking at the total cost of riding including the cassette.
- mvdtnz 2y agoWhy would that surprise you? A semi serious mountain biker will go through a cassette on an analog bike in 2 years. You're driving the thing with a huge motor, cargo and an entire extra human. Your expectations must have been unrealistically high.
- dgacmu 2y agoThe difference between a mid-drive (in which all of the force goes through the rear cassette) and a rear hub drive (in which only the pedal force goes through the rear cassette) is large. Also, most people online report over 2k miles on a cassette. Pittsburgh's hills and more force are apparently good for some extra wear. (Also, a 250W motor is fairly small by e-bike standards. They generally start at 250 and go up from there; 750W is not uncommon.)
- adrianN 2y agoI manage to ruin chain and cassette in under a year on my acoustic bike. The trick is to ride fast in all weather and never clean the chain.
- InSteady 2y agoCongratulations, your brief comment has managed to trigger me in 3 different ways.
- devbent 2y agoI just dropped a bunch of money on a Bosch based bike because I was told they are very reliable. I'm going to be very annoyed if that turns out to not be the case....
- glenngillen 2y agoBosch is in a bunch of high end eMTB setups, including a few of my friends’ rides. We do plenty of wet riding, and the bikes have been hit with the hose for years now to clean them off when we’re done. If there’s a problem here I think it must be the frame design or the way they’re installed and not an across the board problem with Bosch components.
- Bootvis 2y agoYour mileage may literally vary but indeed: this no problems with my Bosch either.
- m463 2y ago> they're typically placed at an angle that catches all the run off aren't they also directly behind the front wheel? fenders, fenders, fenders. something unsexy with a flap / mudguard.
- joe_the_user 2y agoI can't see how mid-drives are significantly superior. An electric motor doesn't need any gear advantage and sending more force to the rear wheel seems like it's actually a disadvantage since it put more stress on bicycle components that are often designed for just human levels of force. As far as I can tell, the mid-drives became dominant just 'cause people wanted to have something the looked more "seamless". I have rear drive ebike (Avanton Pace 300 v1) and I'm very happy with it (it was also cheap as a show room model). It's responsive and I can pedal up any hill to about a 25% grade. The controller is still mid-frame and the battery inset into the down tube. Thinking about it, my ideal ebike would be a heavy duty frame with all the components just bolting on (plus could use power tool batteries).
- vvanders 2y agoElectric motors have a wide power band but it isn't infinite[1], gearing does make a difference. If I'm in a higher gear on an incline my motor has significantly less usable torque vs shifting down to a gear that's closer to the power band. Now if that is worth the complexity/cost is a fair debate but there are mechanical advantages to mid-drive motors. [1] https://forums.electricbikereview.com/threads/ebike-motor-power-curve-comparison-chart-bosch-yamaha-shimano-brose.14085/ https://forums.electricbikereview.com/threads/ebike-motor-po...
- deleted 2y ago[deleted]
- jdietrich 2y agoIn the EU, e-bikes are limited to a maximum power output of 250 watts - anything over that is a motorbike. That's basically the same power output as a decently fit cyclist. A mid-drive allows for sustained high torque even with limited power. Water ingress issues aside, mid-drives also tend to be more durable in off-road applications where the rear wheel is subject to severe shock and vibration.
- joe_the_user 2y ago
- mperham 2y agoSpecialized had problems with their last gen of the Brose motor (2.1?), leading to lots of premature failure. I’d not heard of significant problems with Bosch units, it’s always hard to determine what is truly a design flaw vs a few anecdotes.