Replace the gear cassette on an e-Bike?

Sander_Koop

Finding my (electric) wheels
Jun 22, 2020
22
4
Hi all.

I'm a n00b here, and apologies if this has been covered before, but there is TOO much to search!

I have a Samebike LO26. Excellent cheap e-bike, and I love it - but. I feel the gearing is off. At full speed, i really feel I need an extra gear - i'm pedalling like a madman, and I think adding an extra (smaller) cog to the rear cassette would help massively. I never ever even shift down from the top cog on the front, completely unnecessary.

Does anybody know how/if that would work with the PAS settings etc.? I know the gear shifter has the capacity for an extra cog, as it has 6, and the shifter goes to 7. And if it can be done, what cassette would work/fit?

I'm also going to upgrade the front suspension to a fork that doesn't feel like it's going to snap, and has preload adjust. And a set of road slicks (I dont't offroad, ever)!
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
2,214
562
78
Hi all.

I'm a n00b here, and apologies if this has been covered before, but there is TOO much to search!

I have a Samebike LO26. Excellent cheap e-bike, and I love it - but. I feel the gearing is off. At full speed, i really feel I need an extra gear - i'm pedalling like a madman, and I think adding an extra (smaller) cog to the rear cassette would help massively. I never ever even shift down from the top cog on the front, completely unnecessary.

Does anybody know how/if that would work with the PAS settings etc.? I know the gear shifter has the capacity for an extra cog, as it has 6, and the shifter goes to 7. And if it can be done, what cassette would work/fit?

I'm also going to upgrade the front suspension to a fork that doesn't feel like it's going to snap, and has preload adjust. And a set of road slicks (I dont't offroad, ever)!
I did it myself on my last e-bike, which was a fully legal one that would only assist up to 25KMH.
The cassette change made the ride much more comfortable, not needing to maintain such high revolutions with my feet....
Warning, there are at least two different types of cassette available, they are not compatible.
I ordered the wrong type first!!! But it was not expensive.
Also, mine needed a small (but cheap) special tool to remove and replace the cassette.
Once I got the right one and the tool, it was easy to do IMHO.
Depending on how old the bike is and how many miles you have ridden, a new chain at the same time may be a good idea.
Making the gear ring larger, is also a possibility that I have never tried myself, but I had it in mind, if the cassette change was not fully effective.
Best wishes
Andy
 
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vfr400

Esteemed Pedelecer
Jun 12, 2011
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there are two types of gear clusters, which the uninformed call cassettes, but in cycling speak a cassette is a gear cluster that goes on a spline (technical term Free-hub) and the cluster that screws onto a threaded boss is called a free-wheel.

A six speed is likely to be a freewheel. You should be able to fit any freewheel up to seven speeds. Most freewheels have 14 teeth on the top gear, so it makes no difference how many gears you have because the top gear is always the same and too low. cassettes normally have 11T top gear, which is much better for an electric bike.

There is a solution, and that's the DNP freewheel that has 11T top gear, which you can get in 7 speed.

You will need freewheel removal tool to get your old one off, and it needs to have a large enough hole to go over the axle. Be careful, most don't.
 
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WheezyRider

Esteemed Pedelecer
Apr 20, 2020
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there are two types of gear clusters, which the uninformed call cassettes, but in cycling speak a cassette is a gear cluster that goes on a spline (technical term Free-hub) and the cluster that screws onto a threaded boss is called a free-wheel.

A six speed is likely to be a freewheel. You should be able to fit any freewheel up to seven speeds. Most freewheels have 14 teeth on the top gear, so it makes no difference how many gears you have because the top gear is always the same and too low. cassettes normally have 11T top gear, which is much better for an electric bike.

There is a solution, and that's the DNP freewheel that has 11T top gear, which you can get in 7 speed.

You will need freewheel removal tool to get your old one off, and it needs to have a large enough hole to go over the axle. Be careful, most don't.
I've got a DNP 7 I bought a few months back I'd like to put onto my SWX02. At the moment it has a Shimano 7 speed on it with 14t smallest cog. The removal tool I have doesn't fit. Is there one you could recommend? I presume there are a lot of different Shimano freewheel tools as designs have changed over the years? It's an MF-TZ21 freewheel.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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I've got a DNP 7 I bought a few months back I'd like to put onto my SWX02. At the moment it has a Shimano 7 speed on it with 14t smallest cog. The removal tool I have doesn't fit. Is there one you could recommend? I presume there are a lot of different Shimano freewheel tools as designs have changed over the years? It's an MF-TZ21 freewheel.
The DNP one fits.
I think this is one, though the price is a bit steep. I used to sell them on Ebay for £3:
They normally look more like this:
 

Woosh

Trade Member
May 19, 2012
20,370
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I bought a few DNP 11T-34T 8-speed freewheels recently and paid about £3 per unit in EU's anti dumping duty.
Previously, I sold them for £12 each, now £18.
That's why you don't see much DNP with 11T on the net.
 

gsm.terra

Pedelecer
Aug 3, 2020
162
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Edinburgh
would fitting a front derailleur and cog not have a similar effect?
 

WheezyRider

Esteemed Pedelecer
Apr 20, 2020
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The DNP one fits.
I think this is one, though the price is a bit steep. I used to sell them on Ebay for £3:
They normally look more like this:
Thanks for the info, although the one I need to get off is the Shimano (MF-TZ21) :)
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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Basildon
Thanks for the info, although the one I need to get off is the Shimano (MF-TZ21) :)
They all have the same spline. You need one that will clear the axle. You can get any one you want as long as the whole is big enough. Now we're back to post #3 and we can do it all again.
 

wheeliepete

Esteemed Pedelecer
Feb 28, 2016
2,047
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Devon
If you get the DNP one in vfr's post #5 it will fit ALL freewheels. You need the extra length to remove the DNP freewheel. Park Tool FR-1.3 also fits.
 
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Sander_Koop

Finding my (electric) wheels
Jun 22, 2020
22
4
I bought a few DNP 11T-34T 8-speed freewheels recently and paid about £3 per unit in EU's anti dumping duty.
Previously, I sold them for £12 each, now £18.
That's why you don't see much DNP with 11T on the net.
It already has one. It has a front derailleur & 3 sprockets. Which are pretty useless, I stuck it on the largest sprocket & haven't touched the front shifter since.
 

Sander_Koop

Finding my (electric) wheels
Jun 22, 2020
22
4
there are two types of gear clusters, which the uninformed call cassettes, but in cycling speak a cassette is a gear cluster that goes on a spline (technical term Free-hub) and the cluster that screws onto a threaded boss is called a free-wheel.

A six speed is likely to be a freewheel. You should be able to fit any freewheel up to seven speeds. Most freewheels have 14 teeth on the top gear, so it makes no difference how many gears you have because the top gear is always the same and too low. cassettes normally have 11T top gear, which is much better for an electric bike.

There is a solution, and that's the DNP freewheel that has 11T top gear, which you can get in 7 speed.

You will need freewheel removal tool to get your old one off, and it needs to have a large enough hole to go over the axle. Be careful, most don't.
Cool, thanks. That's useful information. I'll see if I can find the right tool.
 

WheezyRider

Esteemed Pedelecer
Apr 20, 2020
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They all have the same spline. You need one that will clear the axle. You can get any one you want as long as the whole is big enough. Now we're back to post #3 and we can do it all again.

I was hoping you would know of one that would fit the axle and the spline. I took a punt and ordered one. It arrived today, spline fitting is ok, but hole too small :rolleyes: of course they don't tell you the hole size when you order on line. So I'll either have to remove the axle first or put the tool on the CNC and re-bore it.
 

WheezyRider

Esteemed Pedelecer
Apr 20, 2020
1,690
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Would this fit?

If you have a cassette freewheel, yes, but as vfr has been trying to explain, it sounds like you have a screw on freewheel. If that's the case the DNP7 is about the only game in town with an 11t smallest cog.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
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Basildon
I was hoping you would know of one that would fit the axle and the spline. I took a punt and ordered one. It arrived today, spline fitting is ok, but hole too small :rolleyes: of course they don't tell you the hole size when you order on line. So I'll either have to remove the axle first or put the tool on the CNC and re-bore it.
I already told you above that the DNP one fits.