rear sproket and chain modification on the Agattu

[flecc]

Depends on the steepness of your hills and your own cycling ability Bob. If your's aren't the steepest around, an 18 or 19 tooth is a fairly safe bet, but it's usually best to use a bike first and determine from that what you want.

To tell what you need once you've got the bike and ride it in your area:

If you find you don't need 1st gear, fit a 20 tooth.

If you find you don't need 1st or 2nd, fit an 18 tooth.

and so on.

50cycles will do it pre-delivery if wished as quoted above.
.

 

[burncycle]

Hi,
Im revisiting this thread after reading musicbooks updated commute review of the agattu............

http://www.pedelecs.co.uk/forum/electric-bicycles/1785-agattu-first-impressions-4.html

Again a question.
The steepest hill I will be attempting will be a 1 in 10.
Do you feel it may be of benefit to chane my rear sprocket on my Pro-Connect from the standard 22 tooth to a 20 tooth, pre-delivery by 50 cycles?

Any other Agattu owners got their opinions on the uses of 1st Gear in everyday use.
Or do you use 1st Gear that much on your Agattu?

Regards Bob

 

[flecc]

First gear on these is very rarely used. The only time I used it in testing the heavier Agattu was climbing 20%, double your maximum steepness, and at 72 I'm no superman.

You could go further than a 20 tooth since 10% is a moderate hill and you still wouldn't need 1st gear, though how much depends on your own weight.

I'd suggest 19 or 20 tooth at the outset. Don't forget, with experience you can change it again if wished, a local bike shop doing it quickly and easily for around £20 including labour.
.

 

[burncycle]

First gear on these is very rarely used. The only time I used it in testing the heavier Agattu was climbing 20%, double your maximum steepness, and at 72 I'm no superman.

You could go further than a 20 tooth since 10% is a moderate hill and you still wouldn't need 1st gear, though how much depends on your own weight.

I'd suggest 19 or 20 tooth at the outset. Don't forget, with experience you can change it again if wished, a local bike shop doing it quickly and easily for around £20 including labour.
.

Thanks Flecc !
So what would a 20 or 19 tooth give me in additional assisted speeds Flecc?

 

[stokepa31]

That's the one, 16 tooth 1/8".

That will give maximum power in top gear at up to nearly 14 mph, with assist finally ending by 21 mph. This will shorten the range though, since it will always have power applied unless you cut it at times.
.

Burncycle

I have now definately decided on 16 teeth. dont forget we get an 8 speed hub which means you can go with fewer teeth than on an agattu.

 

[musicbooks]

Hi,
Im revisiting this thread after reading musicbooks updated commute review of the agattu............

http://www.pedelecs.co.uk/forum/electric-bicycles/1785-agattu-first-impressions-4.html

Again a question.
The steepest hill I will be attempting will be a 1 in 10.
Do you feel it may be of benefit to chane my rear sprocket on my Pro-Connect from the standard 22 tooth to a 20 tooth, pre-delivery by 50 cycles?

Any other Agattu owners got their opinions on the uses of 1st Gear in everyday use.
Or do you use 1st Gear that much on your Agattu?

Regards Bob

Hi Bob,
I found that going up the 1 in 5 I was going so slowly in 1st and 2nd that I couldn't feel the power kick at all and I was going so slowly that I almost lost my balance and came off. When I went up a gear or two I got a bit more grip and the power returned .. with a subsequent reduction in effort. It is weird as it is almost the opposite of what normally happens on a non-e bike. I was quite surprisedthough by how much effort I had to put in.. but when I changed up it felt a ittle easier. It is easy to forget how much the power unit is providing..and when I switched it off, I felt like an astronaut returning to Earth after 6 months on a space lab. Quite amazing really..

On the flat, I found the top gears a little light in that as I pedalled at a reasonable pace 15-18mph I was pedalling quite fast without a lot of grip. My gut is telling me that I should reduce the ize of the sprocket but I am going to hold fire for a few more commutes until I get a proper feel of the bike and all the various in and outs f coping with the mountains of Bath

If you have 1 in 10, and you are reasonably fit, I would ask 50c to fit a smaller sprocket. By how much, I don't know.. I'll leave that to someone more experienced.. Hope that helps..

I'll post findings again.. after a few more puffs up the hill.
BW
musicbooks

 

[flecc]

Thanks Flecc !
So what would a 20 or 19 tooth give me in additional assisted speeds Flecc?

A 19 tooth would give assistance to final cut-off at 17.5 mph, a 17 tooth at 19 mph.

As Paul says as well, you could go further, but you'll never know exactly how much until you ride it in your area.

That's why I've posted before on this, if not certain, why not wait until you have the bike? 50cycles charge £15, a bike shop might charge £20, so there's little to be gained from rushing.

Once you have the bike, it will be easy to say exactly what to change it to for yourself and your circumstances.
.

 

[musicbooks]

A 19 tooth would give assistance to final cut-off at 17.5 mph, a 17 tooth at 19 mph.

As Paul says as well, you could go further, but you'll never know exactly how much until you ride it in your area.

That's why I've posted before on this, if not certain, why not wait until you have the bike? 50cycles charge £15, a bike shop might charge £20, so there's little to be gained from rushing.

Once you have the bike, it will be easy to say exactly what to change it to for yourself and your circumstances.
.

Sound advice Flecc

 

[stokepa31]

Sound advice Flecc

Absolutely but i'm just taking a punt that the 16 teeth will give me comparable gearing to a Torq which is very highly geared. I might have it wrong and it will cost me a furthr £20 to have another go!!!

should have added that ive already tested an agattu with a similar setup to the one i'm after too.

P

 

[flecc]

Absolutely but i'm just taking a punt that the 16 teeth will give me comparable gearing to a Torq which is very highly geared. I might have it wrong and it will cost me a furthr £20 to have another go!!!

should have added that ive already tested an agattu with a similar setup to the one i'm after too.

P

Yes, that's entirely valid Paul, since you are in a position to be able to quite fully judge. I think that's right for you anyway, matching the Torq gearing and getting the Panasonic's maximum power quite high up the speed scale.

It's for those not sure it's best to wait. Then an exact judgement is possible, based on the low gears actually used by the individual in their territory.

For example:

Not using 1st, fit a 20 tooth.

Not using 1st and 2nd, fit an 18 tooth.

Not using 1st, 2nd, 3rd, fit a 16 tooth.

Approximates, but very close to ideal.

The only thing likely to vary that is for a person who needs the absolute maximum range, when very high gearing would compromise that.
.

 

[stokepa31]

It's for those not sure it's best to wait. Then an exact judgement is possible, based on the low gears actually used by the individual in their territory.

Agree 100% mate

 

[burncycle]

I think I'll wait and see how the bike performs.
As Flecc said in his Agattu review "we dont do flat in our area".
In Sheffield its all up and down.
My 5 mile commute has 7 hill climbs in it.
At the end of the day im buying an ebike for hill climbing. Once I've climbed the hill, its all down hill. So I dont care about speed on the flat, cus there ain't much of it.

I'll let you know how i get on everyone and if I need to change sprockets.

Thanks for all your help.

 

[Erik]

I've fitted an 18 tooth with the following results:

The added speed means that the wind resistance is clearly felt.

The battery and I get drained much quicker.

The motor is always assisting.

 

[flecc]

I've fitted an 18 tooth with the following results:

The added speed means that the wind resistance is clearly felt.

The battery and I get drained much quicker.

The motor is always assisting.

Exactly as I warned in my review "extra" section, changes from standard usually meaning these consequences. It's inevitable given the limited power motor and the nature of the system.
.

 

[Cyclezee]

I'm thinking of going for a 19 tooth sprocket provided it is not too detrimental to battery performance. I really don't use 1st or 2nd at all and very occasionally 3rd. However I quite often find myself pedaling furiously in 7th and looking for an extra gear.
This is not because I am exceptionally fit by any stretch of the imagination, more the terrain does not demand low gears.

John

 

[flecc]

As reducing cadence is your objective John, in that area even an 18 tooth should be ok, reducing your 15 mph cadence from 65 to 53.
.

 

[Cyclezee]

Yes Flecc, I'm probably erring on the side of caution going for a 19 tooth sprocket, but maybe one day I might want climb a serious hill.

John

 

[musicbooks]

Yes Flecc, I'm probably erring on the side of caution going for a 19 tooth sprocket, but maybe one day I might want climb a serious hill.

John

Hey John,
If you are ever passing through Bath on your Agattu, I can show you a hill or two
BW
musicbooks

 

[burncycle]

I stilll do not fully understand the practicalities of changing the rear spocket on the kalkhoff range.
After reading some of the posts about this weekend regarding the Kalkhoff's, it may have set my mind to change the sprocket on my Pro-Connect (when I get it).
I was thinking of a 18 tooth, that would give me additional assist to 17.5mph (correct me if im wrong).
I was told to do this if you do not need 1st for 2nd gear.
Now here's what I dont understand !
How do the gears react to a tooth change?
Do you loose 1st and 2nd (they dont work).

Please educate me.
Also if anyone tried out the Agattu/Pro-Connect, what did you think about the gearing?

 

[stokepa31_mk2]

I stilll do not fully understand the practicalities of changing the rear spocket on the kalkhoff range.
After reading some of the posts about this weekend regarding the Kalkhoff's, it may have set my mind to change the sprocket on my Pro-Connect (when I get it).
I was thinking of a 18 tooth, that would give me additional assist to 17.5mph (correct me if im wrong).
I was told to do this if you do not need 1st for 2nd gear.
Now here's what I dont understand !
How do the gears react to a tooth change?
Do you loose 1st and 2nd (they dont work).

Please educate me.
Also if anyone tried out the Agattu/Pro-Connect, what did you think about the gearing?

You don't loose them Bob but by redcing the size of the rear sprocket, every gear is shifted higher. In the case of going from 22 to 18 you are effectively making 1st gear like the old third gear before the change of sprocket.

Essentially the rear sprocket is the multiplier for all the gears stuffed inside the hub. increase the rear sprocket the whole lot goes lower, decrease and it all goes higher.

P