Simple top speed question guys.

[minnemike]

What top speed can I expect from the various mid drive motor makers if I have a single speed rear? Let's say standard 14 or 16 teeth?

Maybe comparing a Cyclone mini 2000w vs TSDZ2 for instance...

I have a non-Rohloff IGH and expecting it might shred with my build... so I'm planning ahead!

[jjstripes]

There's so many variables here, and just knowing the number of teeth in the rear is not enough. Depends a lot of the controller, how the controller is programmed, battery voltage, front teeth.

I am running a CYC X1 Pro Gen 2 w/ the stock controller and a 52 volt battery, 29er wheels. I did a little custom programming through the CYC smartphone app, but nothing crazy. The other day I was cruising (I don't remember what gear I was in) and it started to feel too fast and I looked down at my garmin and I was going 45 MPH. Way too fast and uncomfortable. It was still accelerating too.

[Skaiwerd]

Using the map my ride app I’ve reached 38 mph going downhill on this retro modern kinda board track racer. It’s long and heavy, good for speed. 27.5 inch Schwalbe supermoto x 2.4” Tires that are 2.75” on 50mm rim at 30psi. It’s has 6 6s multistar 16ah batteries, 3 in series, so I’m running 72 (75 starting out) volts. So it’s no lightweight. I think I went single speed at that point using 16 tooth rear cog. This is the cyclone 3000v but in frame as the frame is huge.

[minnemike]

There's so many variables here, and just knowing the number of teeth in the rear is not enough. Depends a lot of the controller, how the controller is programmed, battery voltage, front teeth.

I am running a CYC X1 Pro Gen 2 w/ the stock controller and a 52 volt battery, 29er wheels. I did a little custom programming through the CYC smartphone app, but nothing crazy. The other day I was cruising (I don't remember what gear I was in) and it started to feel too fast and I looked down at my garmin and I was going 45 MPH. Way too fast and uncomfortable. It was still accelerating too.

Thanks for the replies...

I'd likely be running a 52v 17ah - 30 amp continuous rated battery, so I'll likely dial down whatever controller to 25 amps or so - standard 26" wheel.

It's gonna be a street cruiser.

Sounds like I can get at least a decent 25mph+ cruising speed out of it with a standard single gear setup? Probably quite a bit above comfortable pedaling pace (15-18mph) if wanted? That's what I'm looking for anyways. Want to be able to pedal along manually and also be able to cruise faster when needed... or uphill aid.

Your CYC is really nice - thinking about getting their lower power stealth version coming out this Sept.

Here's their specs the sent me:

The X1 Stealth is around 1.5kg lighter than X1 PRO. BAC855 controllers.
2kW-2.5kW.
Torque sensing.

Scheduled to release in October according to the current schedule, may have further delays.

[Balmorhea]

The main drawback to a single gear with a mid drive is if you get your desired top speed, you lose climbing ability (and vice versa).

My BBS02 easily exceeded 25mph in its 44/16 gear (with 700C wheel)— and my bike and I are big and heavy. But it would not have climbed well in that gear, and it would have gotten hot.

Figure out how you’re going to add derailleur gearing to your bike as a fallback, should your gearhub bite the dust. Running a mid drive through a single speed is a bad idea.

[minnemike]

The main drawback to a single gear with a mid drive is if you get your desired top speed, you lose climbing ability (and vice versa).

My BBS02 easily exceeded 25mph in its 44/16 gear (with 700C wheel)— and my bike and I are big and heavy. But it would not have climbed well in that gear, and it would have gotten hot.

Figure out how you’re going to add derailleur gearing to your bike as a fallback, should your gearhub bite the dust. Running a mid drive through a single speed is a bad idea.

Yeah, that would be a good idea except for the fact that my drop out is only 120mm... I'd be needing to cold set to 135mm which would be my last desperate plan of action. Not aware of any cassette setup under 135mm.

[Balmorhea]

Figure out how you’re going to add derailleur gearing to your bike as a fallback, should your gearhub bite the dust. Running a mid drive through a single speed is a bad idea.

Yeah, that would be a good idea except for the fact that my drop out is only 120mm... I'd be needing to cold set to 135mm which would be my last desperate plan of action. Not aware of any cassette setup under 135mm.

5-speed spacing is 120mm. Freewheels hubs didn’t have chronic problems with axle bending and breakage when they were spaced for 5-speed, like later when they were spaced for 7. If you can’t find a good 5-speed hub set up with 120mm spacing already, you can remove spacing from a wider one, or add spacing to the right side of a 110mm BMX hub. Pay a professional to dish the rim back to center, if you don’t already understand that procedure.

With e-assist, you don't need a huge gear range. A 14-28 5-speed freewheel can be plenty, if the high gear gives you just the top speed you want.

It’s still easy to get 5-speed index shifters and Hyperglide style freewheels, and that stuff is dirt cheap.

[minnemike]

Figure out how you’re going to add derailleur gearing to your bike as a fallback, should your gearhub bite the dust. Running a mid drive through a single speed is a bad idea.

Yeah, that would be a good idea except for the fact that my drop out is only 120mm... I'd be needing to cold set to 135mm which would be my last desperate plan of action. Not aware of any cassette setup under 135mm.

5-speed spacing is 120mm. Freewheels hubs didn’t have chronic problems with axle bending and breakage when they were spaced for 5-speed, like later when they were spaced for 7. If you can’t find a good 5-speed hub set up with 120mm spacing already, you can remove spacing from a wider one, or add spacing to the right side of a 110mm BMX hub. Pay a professional to dish the rim back to center, if you don’t already understand that procedure.

With e-assist, you don't need a huge gear range. A 14-28 5-speed freewheel can be plenty, if the high gear gives you just the top speed you want.

It’s still easy to get 5-speed index shifters and Hyperglide style freewheels, and that stuff is dirt cheap.

Do you happen to know an example of a 5 speed 120mm setup that I can search for? Maybe I'm not looking in the right places but not able to find any cassette set up like that - only IGH.

[99t4]

Try a FLBS that keeps crates of old parts in the back. In my area there's a bike shop that refurbishes donated bikes for needy families. They have crates of old stuff they take off the old bikes; brakes, shifters, deraillers, cranks, pedals, etc. and sell them cheap. You may have something similar in your area?

[Balmorhea]

Do you happen to know an example of a 5 speed 120mm setup that I can search for? Maybe I'm not looking in the right places but not able to find any cassette set up like that - only IGH.

You’re not looking for a cassette hub, because there are no 5-speed cassettes. What you want is a freewheel hub. If you want a new one, you will be respacing it from either a 7-speed or a single speed hub.

It’s an easy thing to do, but it requires thin cone wrenches and an assortment of different width axle spacers. In some cases (quick release hubs), you might have to cut down the axle by the amount you reduced the spacing. If it’s a whole wheel, you then have to adjust the spoke tension to bring the rim to the center of the axle (which isn’t as easy as respacing the axle). So the easiest thing is to go to a bike shop and tell them you want a wheel with 120mm of axle spacing and 30mm of freewheel spacing from the thread shoulder to the locknut face. They can take care of the details for you.

Once you have the wheel sorted out, you need a 5-speed freewheel and a 5, 6, 7, or 8-speed rear derailleur (with an integrated mounting claw, if your frame doesn't have a derailleur hanger). You’ll need either a 5-speed index shifter or a friction shifter. And you’ll need a 5/6/7 or 6/7/8 multi-speed chain, because a single speed chain isn’t narrow enough or long enough to pass through the derailleur. “SIS compatible” or “index compatible” is what you’re looking for in these things, if you want them to click shift.

This is easy work for a bike mechanic, so only do it yourself if you find it entertaining.

[minnemike]

Try a FLBS that keeps crates of old parts in the back. In my area there's a bike shop that refurbishes donated bikes for needy families. They have crates of old stuff they take off the old bikes; brakes, shifters, deraillers, cranks, pedals, etc. and sell them cheap. You may have something similar in your area?

We do have one in town that's really awesome as well. I'll check them out. This would be the easiest path by far. Thanks for the idea.

[minnemike]

Do you happen to know an example of a 5 speed 120mm setup that I can search for? Maybe I'm not looking in the right places but not able to find any cassette set up like that - only IGH.

You’re not looking for a cassette hub, because there are no 5-speed cassettes. What you want is a freewheel hub. If you want a new one, you will be respacing it from either a 7-speed or a single speed hub.

It’s an easy thing to do, but it requires thin cone wrenches and an assortment of different width axle spacers. In some cases (quick release hubs), you might have to cut down the axle by the amount you reduced the spacing. If it’s a whole wheel, you then have to adjust the spoke tension to bring the rim to the center of the axle (which isn’t as easy as respacing the axle). So the easiest thing is to go to a bike shop and tell them you want a wheel with 120mm of axle spacing and 30mm of freewheel spacing from the thread shoulder to the locknut face. They can take care of the details for you.

Once you have the wheel sorted out, you need a 5-speed freewheel and a 5, 6, 7, or 8-speed rear derailleur (with an integrated mounting claw, if your frame doesn't have a derailleur hanger). You’ll need either a 5-speed index shifter or a friction shifter. And you’ll need a 5/6/7 or 6/7/8 multi-speed chain, because a single speed chain isn’t narrow enough or long enough to pass through the derailleur. “SIS compatible” or “index compatible” is what you’re looking for in these things, if you want them to click shift.

This is easy work for a bike mechanic, so only do it yourself if you find it entertaining.

Would love to get experienced with all of this. But for this build I really dont want to run into any unneeded complication I might create for myself. Maybe I'll save this for another build I have that has a much less of an investment involved.

Appreciate all the info here. Definitely on course now.