How to fool Kalkhoff engine...

[Pinbin]

How to fool Kalkhoff motor...

Hello everyone,

I am a new owner of a Kalkhoff Agattu. Upon purchase, I was told I could fool the motor by switching a sprocket or something like that...?

At the time I said no as I was nervous to do any modifications, but now I kinda think it would be useful...

Can someone kindly explain what this means, how it will affect my bike/ride, and particularly- how to do this.

Thanks in advance

 

[iaing]

Hello

Try these two:

http://www.pedelecs.co.uk/forum/electric-bicycles/1750-rear-sproket-chain-modification-agattu.html?highlight=KALKHOFF+GEARING (especially, perhaps, post number 13)

repairs

Changed my sprocket - a big improvement.

Iain

 

[tillson]

The thread titled busetti-ebay-60-mile-range has an explanation from about page 2 onwards.

 

[tangent]

I calculated the gear ratios for various rear sprockets and supplied a table in this thread:

http://www.pedelecs.co.uk/forum/search.php?searchid=360403

This will help you work out which gear moves where following a sprocket change. Note that the table is for a 41T chainwheel, but I can see that the new Agattu is advertised as having a 35T chainwheel. Is this true? If so this is an unwelcome change, as smaller sprockets wear faster than larger ones. Let me know if there really is a 35T chainwheel and I will post a new table.

Changing the motor sprocket from a 9T to 11T may be worthwhile, but depends on your riding style. Doing this means that the motor assist will continue to higher cadences, but the level of assist in each mode will be reduced by 9/11. i.e. it will change the assistances to 1:0.41, 1:0.82 and 1:1.64.

 

[tillson]

I calculated the gear ratios for various rear sprockets and supplied a table in this thread:

http://www.pedelecs.co.uk/forum/search.php?searchid=360403

This will help you work out which gear moves where following a sprocket change. Note that the table is for a 41T chainwheel, but I can see that the new Agattu is advertised as having a 35T chainwheel. Is this true? If so this is an unwelcome change, as smaller sprockets wear faster than larger ones. Let me know if there really is a 35T chainwheel and I will post a new table.

Changing the motor sprocket from a 9T to 11T may be worthwhile, but depends on your riding style. Doing this means that the motor assist will continue to higher cadences, but the level of assist in each mode will be reduced by 9/11. i.e. it will change the assistances to 1:0.41, 1:0.82 and 1:1.64.

It would appear that there is now a 35 tooth chain wheel. A member reports having his new Agattu supplied with one.

 

[Biged]

Like tillson says check out busetti-ebay-60-mile-range from yesterday, it started out with a Busetti range discussion but then went to my 'New' Agattu/Dover range/sprockets/chainwheels etc. it should answer your question if you have a 'New' Agattu
I should probably have started a new topic and not just jumped in but thats me everytime

 

[flecc]

Here's the link to my post etc in the Busetti thread:

Panasonic sprocket relationships

but read the immediately preceding and following posts as well.
.

 

[Pinbin]

Gotta love the speed all these replies came in- It's great to feel welcomed to a community like this
I'm particularly honored to have the great Flecc replying on my first posting here- I loved your review on the Kalkhoff, and perhaps may even have been pushed over the edge by it.
When I was buying the bike, another couple walked in, and they too had been on this forum, I said- "Did you read Flecc's review?" "Of course" they said, "that's why we're here!"
Time for commision me thinks

 

[flecc]

When I was buying the bike, another couple walked in, and they too had been on this forum, I said- "Did you read Flecc's review?" "Of course" they said, "that's why we're here!"
Time for commision me thinks

Guilty as charged!

No need for commission though, the bike would have sold itself on it's qualities anyway, especially at that time when the current choices didn't exist.
.

 

[tangent]

I have just read the Busetti thread - seemed to be mostly about Kalkhoff's!

So the Agattu now comes with a 35T chainwheel and 19T rear sprocket. This must mean they have also tweaked the electronics, otherwise the power will not cut out until about 17.4mph. Or have they fitted a 8T motor sprocket?

 

[flecc]

So the Agattu now comes with a 35T chainwheel and 19T rear sprocket. This must mean they have also tweaked the electronics, otherwise the power will not cut out until about 17.4mph. Or have they fitted a 8T motor sprocket?

It's still a 9 tooth motor sprocket when checked, so the electronics have probably been tweaked.

It probably wouldn't matter if not tweaked, since the combination of the advanced power phase-down from 13 mph and the 10% tolerance on the assist limit would still leave the system legally ok. Although the consumption would be increased, the supply of the bike with the 18 Ah battery on most models now should more than compensate for that.
.

 

[tangent]

Links to German ebay supplier for 9, 11, 12, 13, 14T motor sprockets:

Motorritzel 9,11,12,13,14 Z. Panasonic Pedelec-Motor bei eBay.de: Fahrräder (endet 24.03.11 20:45:39 MEZ)

The 14T must be quite insane. For people who really do like a high cadence.

 

[tangent]

It's still a 9 tooth motor sprocket when checked, so the electronics have probably been tweaked.

It probably wouldn't matter if not tweaked, since the combination of the advanced power phase-down from 13 mph and the 10% tolerance on the assist limit would still leave the system legally ok. Although the consumption would be increased, the supply of the bike with the 18 Ah battery on most models now should more than compensate for that.
.

Does the power start to phase-down at 13 mph? I thought it started much lower than this, around 10mph. Not sure where I got this information from though.

 

[flecc]

No, it starts at 9.4 mph, but if you check you'll see I said the phase-down is advanced at 13 mph, i.e. greatly reduced power.

Hence my saying legality barely entered into the increase of final cutoff from 15 to 17.4 mph since the power assist level is so low in that speed region.
.