MOSH/Cty Pedal Cadence - change gear ratio?

Cereal1

New Member
Region
USA
I am one of the many who ordered a Serial 1 Mosh during the Best Buy 50% off sale. The bike arrived, and it is a pretty nice bike, particularly for the price. I now have 15 days to decide if I want to keep it, or return it.

The reason I am considering returning it is the pedal cadence. In order to reach 20MPH you have to be peddling at an absurdly high cadence, comfortably you can only reach about 12 - 15MPH before your legs look like road runner. Has anyone considered or tried changing either the front or rear sprocket to get higher gearing? Gates makes a variety of options: https://www.gatescarbondrive.com/products/front-sprockets

The motor seems torquey enough that I think you could increase the gear ratio 20% or so without greatly impacting performance on hills or off the line.

If you could address this limitation, it seems like it will make a fairly nice commuter. I would prefer to get to work 20% faster.
 
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Were you ever able to resolve the gearing issue and, if so, how was it done? I'm going to guess it would be as simple as swapping the front sprocket.

The Mosh/City is an incredible mid-drive value at the current $1520 Best Buy price. Walmart has a grungy Hyper mid-drive for $1398. For a measely $122 more, the Mosh/City seems like a no-brainer 'if' it weren't for the low gearing that prohibits anything over 15mph.
 
I didn't return the bike, but I haven't gotten around to fixing this issue either. It is probably as simple as new front sprocket and belt (changing the sprocket will change the belt length and there is not much adjustment), but you would have to work out the ratios. You could also change both the front and rear sprockets to try and keep the belt length about the same.

Let us know if you get around to doing this.

The other persistent issue I am having with the bike are the breaks squealing like crazy. I thought I didn't bed them in right, but after cleaning and sanding the pads and rotors, then carefully bedding them in, it still makes a god awful racket.

Overall, I still think the bike is OK value at 50% off MSRP, but I would not pay more than that.
 
The brakes on my Rush/CTY Speed are quiet. Like you said, it’s very important to bed them in properly. If you didn’t do so when they were new, you‘ll likely need to replace the pads.

Serial 1 has a great tutorial on how to bed them in properly.


They also have a tutorial on how to replace the pads.

 
That is what I did.... They were quiet for a while then got progressively worse. After I sand them and bed them in they are quiet again for a few miles then get worse. Next option is to try replacing the pads.
 
I didn't return the bike, but I haven't gotten around to fixing this issue either. It is probably as simple as new front sprocket and belt (changing the sprocket will change the belt length and there is not much adjustment), but you would have to work out the ratios. You could also change both the front and rear sprockets to try and keep the belt length about the same.

Let us know if you get around to doing this.

The other persistent issue I am having with the bike are the breaks squealing like crazy. I thought I didn't bed them in right, but after cleaning and sanding the pads and rotors, then carefully bedding them in, it still makes a god awful racket.

Overall, I still think the bike is OK value at 50% off MSRP, but I would not pay more than that.
Agreed. Like I said, $1520 for what appears to be a high-quality mid-drive (with a belt, yet) seems like a steal, to me, even if it doesn't have the latest model's USB port and Google app. And, unlike all the other Serial 1 models at Best Buy, it's still possible to order the Mosh/City (in any size, yet). The only other failing of the Mosh/City is the lack of a proper LED info controller screen, but that seems relatively minor for all the other stuff you get.

Since it doesn't appear anyone has performed the DIY sprocket/belt upgrade, it would be nice if the Serial 1 rep who monitors this site could chime in on it. I would guess the downside would be a slightly slower start from rest, but I would hope the trade-off for a more accessible 20mph top speed would be worth it.

In fact, maybe it's something Serial 1 could change on newer versions. It's a real pisser when you can't get to anywhere near 20mph on a top-tier ebike without having to pedal like a maniac. That's something more emblematic of a Chinese cheapo with a limited gearset or single speed.
 
I would be quite surprised if anyone could get to 20mph on the flats. If I pedal like an absolute maniac, I can get to about 15-16mph, but can't hold that cadence for long. It is quite uncomfortable to peddle that fast against almost no resistance.

I don't think changing the gear ratios would be an issue - my commute has some pretty steep sections (I live in Colorado) and I can comfortably hold speed at the 1/2 assist setting, so increasing the gear ratio by 20 - 25% should still be fine. Speed off the line is definitely no issue with even 1/2 assist - the motor is quite torquey.

Anyway a gear ratio change will be a spring project.
 
I would be quite surprised if anyone could get to 20mph on the flats. If I pedal like an absolute maniac, I can get to about 15-16mph, but can't hold that cadence for long. It is quite uncomfortable to peddle that fast against almost no resistance.

I don't think changing the gear ratios would be an issue - my commute has some pretty steep sections (I live in Colorado) and I can comfortably hold speed at the 1/2 assist setting, so increasing the gear ratio by 20 - 25% should still be fine. Speed off the line is definitely no issue with even 1/2 assist - the motor is quite torquey.

Anyway a gear ratio change will be a spring project.
I wonder if the reason for the gearing on these lower-tier ebikes has to do with liability/legal concerns. Class 1 (PAS only) ebikes are required to be no faster than a 20mph top speed, and the least expensive way to do that may be via the gearing, i.e., no way to pedal fast enough to get anywhere near 20mph. It might be a bit better with derailleur-equipped bikes but, on a single speed, well, the rider is simply SOL to a much lower cruising speed (like 12-13mph) and virtually impossible to do any sustained higher speed unless they do exactly what's being proposed, i.e., change one or both sprockets.
 
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I see that Best Buy still has the Mosh and Rush still listed on their site. I am in New Orleans. Says 3 days for Mosh and 10 for Rush. However, I have heard people say they have bene having trouble actually getting the orders delivered. Anyone else had delivery issues?
 
I test rode eviolo cvt and just hated the feeling and drag. but good bikes nevertheless. I am used to derailleurs I guess.
 
I would be quite surprised if anyone could get to 20mph on the flats. If I pedal like an absolute maniac, I can get to about 15-16mph, but can't hold that cadence for long. It is quite uncomfortable to peddle that fast against almost no resistance.

I don't think changing the gear ratios would be an issue - my commute has some pretty steep sections (I live in Colorado) and I can comfortably hold speed at the 1/2 assist setting, so increasing the gear ratio by 20 - 25% should still be fine. Speed off the line is definitely no issue with even 1/2 assist - the motor is quite torquey.

Anyway a gear ratio change will be a spring project.
Worst case scenario, if you can't find a belt size that fits with the different sprockets, you may have to install a small, fixed tensioner to take the slack.
Also they have a model that they advertise as 28mph, so you may want to look at what sprocket combination they use on that as it looks like the frames are all the same.
 
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