Chain ring tooth selection

bellandbottle

Active Member
Region
United Kingdom
I am slowly changing various components on my Vado 4 to suit my personal situation - having changed the tyres, the grips and the seatpost so far.

I have noticed that I am only using the smallest 3 cogs on the cassette, and I would rather be operating a couple of cogs up from that - the chainring I have is 40T.

In addition, if I want to increase the size of the chainring with Shimano components it is really quite expensive.

I am quite a keen cyclist who has recently moved over to an ebike, and I ride 99% of the time on Eco because I am looking for the exercise in our local area, which is quite short of hills. I plan to increase my normal ride to 30 miles soon, but will need to do some map work.

I am limited to 15.5 mph by legislation, if that is a factor.

I would appreciate any inputs.
 
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I am slowly changing various components on my Vado 4 to suit my personal situation - having changed the tyres, the grips and the seatpost so far.

I have noticed that I am only using the smallest 3 cogs on the cassette, and I would rather be operating a couple of cogs up from that - the chainring I have is 40T.

In addition, if I want to increase the size of the chainring with Shimano components it is really quite expensive.

I am quite a keen cyclist who has recently moved over to an ebike, and I ride 99% of the time on Eco because I am looking for the exercise in our local area, which is quite short of hills. I plan to increase my normal ride to 30 miles soon, but will need to do some map work.

I am limited to 15.5 mph by legislation, if that is a factor.

I would appreciate any inputs.
With a motor you’ll need to be mindful of the torque of a new sprocket along with the new pull amount on the chain. The motor you’ll need maximum speed and torque specs or you’ll risk stressing it prematurely.
 
Some countries use a 48 tooth chainring on the Vado. If you ride at higher speeds most of the time the bigger chainring is the way to go. It gives you a better chain line and your cassette will last longer.
 
I'd go for a larger chain ring, and dare I say it another bicycle - one without a motor. I have a few bikes, and switch between powered and non-powered frequently.
 
Some countries use a 48 tooth chainring on the Vado. If you ride at higher speeds most of the time the bigger chainring is the way to go. It gives you a better chain line and your cassette will last longer.

That was my thinking too - on my mechanicals, I would never be on the smallest cog unless going downhill. I will take a look at my options now - many thanks :).
 
I'd go for a larger chain ring, and dare I say it another bicycle - one without a motor. I have a few bikes, and switch between powered and non-powered frequently.

I'm afraid that I am getting to an age where a bit of help is welcome, at least some of the time :).
 
At last I have figured out to search this forum :) , and this question was asked back in 2018, for the same reason:


Some helpful info there.
 
... on my Vado 4 ....
I have noticed that I am only using the smallest 3 cogs on the cassette, and I would rather be operating a couple of cogs up from that - the chainring I have is 40T.

In addition, if I want to increase the size of the chainring with Shimano components it is really quite expensive.

... exercise in our local area, which is quite short of hills. ...

I am limited to 15.5 mph by legislation, if that is a factor.

Being limited to 15.5 mph you should change the chainring to more than 40T but don't take the 48T as it's too much.
You can buy Deckas 104BCD chainring narrow wide in any size between 40T and 52T
 
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At last I have figured out to search this forum :) , and this question was asked back in 2018, for the same reason:


Some helpful info there.

Hey Bell, I too did a lot of riding on my old Trek road bike but age was beginning to catch up. Hence, the Vado.
Like you, I felt the gearing needed to be adjusted.

I went with a 48t chain ring to stop using only the three smallest gears. At the same time I went with a new Shimano cassette to close the huge gaps between gears, a 11-25 to keep the ratios close. We live on the Delaware coast; pretty flat, no mountains to speak of. It rather fun to shift one gear while maintaining cadence. Like a car with a close ratio tranny.
Other mods: I cut off about 1.75 inches from the ends of the handlebars. Now my arms stay closer to my body.

I found my feet slipping off the pedals if the bottoms got wet or sandy. I got a set of Crank Bros pedals with little screws sticking up, like little spikes. I love these. Very effective.

Curious to learn where you live with such restrictive speed limits for bikes?

Cheers
 
Being limited to 15.5 mph you should change the chainring to more than 40T but don't take the 48T as it's too much.
You can buy Deckas 104BCD chainring narrow wide in any size between 40T and 52T

Many thanks for that - I can buy a Deckas 44T which would be a halfway house. I am going to chat to my LBS people, who are very helpful, and check about my warranty (always assuming they are working in the lockdown).

I probably need a new chain anyway, so I will consider asking them to fit it if it eases the warranty situation.

The rather strange thing is that the Vado 6 has a 48T chainring.
 
Hey Bell, I too did a lot of riding on my old Trek road bike but age was beginning to catch up. Hence, the Vado.
Like you, I felt the gearing needed to be adjusted.

I went with a 48t chain ring to stop using only the three smallest gears. At the same time I went with a new Shimano cassette to close the huge gaps between gears, a 11-25 to keep the ratios close. We live on the Delaware coast; pretty flat, no mountains to speak of. It rather fun to shift one gear while maintaining cadence. Like a car with a close ratio tranny.
Other mods: I cut off about 1.75 inches from the ends of the handlebars. Now my arms stay closer to my body.

I found my feet slipping off the pedals if the bottoms got wet or sandy. I got a set of Crank Bros pedals with little screws sticking up, like little spikes. I love these. Very effective.

Curious to learn where you live with such restrictive speed limits for bikes?

Cheers

Thank you for bringing me up to date with the thread you started in late 2018 :) - I am in the UK. The legislation is still a bit up in the air about exactly where ebikes can be ridden.

I was interested to read your other modifications too - thanks for that.
 
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Thank you for bringing me up to date with the thread you started in late 2018 :) - I am in the UK. The legislation is still a bit up in the air about exactly where ebikes can be ridden.

I was interested to read your other modification too - thanks for that.

Yikes! 2018. It‘s true, time does go faster as one gets older. I’ll be 77 in two months.

Bike speed on trails in Delaware state parks is limited to 20 mph as the authorities do not want tourists (who bring considerable revenue to the local economy) run down by ebikes. I typically ride between 16-18 mph, slowing particularly for oncoming dog walkers and small children.

On public roads, the stated traffic speed limit govern. I typically cruise at about 19 - 23 mph using the first or second level of assist, depending on wind velocity and direction. (Biking into a dead-on 12 to 17 mph gusty head wind is NOT fun!)

cheers
 
I've got a little bit of a head start on you - 80 last year.

The 15.5 limit is not too bad on cycleways, and cycling on the road is problematic during the week because of traffic densities. It's fine on Saturdays and Sundays early in the morning, when I go out.
 
Wow! As the Aussies say, Good on ya mate!

Fortunately, Lewes is not a city but rather a relatively small town with wide open roads, many with 8 foot bike lanes. We have bike trails paralleling the coast line. Good location for biking.

Cheers
 
Many thanks for that - I can buy a Deckas 44T which would be a halfway house. I am going to chat to my LBS people, who are very helpful, and check about my warranty (always assuming they are working in the lockdown).

I probably need a new chain anyway, so I will consider asking them to fit it if it eases the warranty situation.

The rather strange thing is that the Vado 6 has a 48T chainring.

Specialized has been confronted with that warranty question before and their answer was no issue, you can do it.

As for the 44T which I think is a good choice for you, you'll need app. four more chain links (124 instead of 120).
You'll need the four chainring bolts for the Deckas as well. Maybe the link following is helpful for you

The Vado 6 is a 28 mph (45 km/h) S-pedelec-model and needs the 48T chainring due to this.

Please consider that your cadence should be above 60 if not 70 to take full advantage of the Brose drive T motor of your Vado 4.0.
 
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Specialized has been confronted with that warranty question before and their answer was no issue, you can do it.

As for the 44T which I think is a good choice for you, you'll need app. four more chain links (124 instead of 120).
You'll need the four chainring bolts for the Deckas as well. Maybe the link following is helpful for you

The Vado 6 is a 28 mph (45 km/h) S-pedelec-model and needs the 48T chainring due to this.

Please consider that your cadence should be above 60 if not 70 to take full advantage of the Brose drive T motor of your Vado 4.0.

@TS25 Many thanks for the informative (and re-assuring) post waiting for me this morning - I will follow up the link today.

I prefer to ride at between 70 and 80, so should be OK, I think.

I am pleased to have found this forum :).
 
@TS25 just curious: Why do you think the 48t would be too much for the EU restricted Vado?
It all starts with the cadence you and the Brose drive T are comfortable with. As you are not going to reach anything close to the 28mph top speed of the S-pedelec with the EU restricted 15,5 mph model a chainring around the 44T leads to a cadence more suitable to its expected speed vario.
The aim should be to use the cogs in the middle of your cassette range and to avoid using the smallest cogs regularly as this leads to increased wear. Well - with the Shimano cassette you could change the smallest cogs seperately to reduce costs as cassettes are expensive. I've added these small spare cogs to my "spare parts department" and could do it by myself. But I prefer to reduce wear if possible.

Presently I'm using a Deckas 40T chainring on my Vado 4.0 although there is a Deckas 46T chainring waiting. This is to force me to increase my average cadence - as I try to avoid using the smaller cogs - before I'll be testing the 46T.
 
TS25, I do not negate what you are saying. I've just made a quick calculation with BikeCalc.com. I have assumed the Vado 4.0 has 47-622 tyres and it is the 11-42t 10-speed cassette. Assuming it is very easy to get to 25 km/h with the powerful motor, the cadence at gear and speed would be:

Cadence rpm
Gear48t chainring25 km/h44t chainring25 km/h
8th48x155844x1564
7th48x187044x1876
6th48x218144x2189
5th48x249344x24102

Bell says he prefers cadences 70-80. Don't you think TS the 48t chain-ring would be better for him? The 44t still requires quite a spinning in the middle gears to get onto 25 km/h.

Why I say so? My S-Vado has the 48t chain-ring and the 11-46 M-7000 cassette. I often ride 25 km/h or even less because I want to (pedestrians, rough terrain) or because I have to (strong headwind). Therefore I often ride in the middle gears even if that's an S-Pedelec. For me, the 48t chain-ring is perfect.
 
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