Woosh Santana CD gearchange quality

[trex]

it looks like the wheel or hub is wonky.
Contact Woosh for a replacement rear wheel.

 

[Artstu]

The largest sprocket has bent outwards a bit at one point by the look of it.

 

[Kudoscycles]

The Kudos e-bike supplier is one of the largest bike manufacturers in the world,they have very impressive R & D facilities,they have several e-bike companies in Europe with good engineers and Kudos is part of the Rally Design group of companies with good designers in the background.
We all tried without success,with many combinations of offsets,gear types to overcome the graunchy gearchange problem. The only effective solution was to have a power cutoff button on the handlebar,which effectively made the bike into a non assisted bike for gearchange purposes. But the button had confusions with 'boost buttons' and anyway it took time for the power to come back in which lost momentum-effectively this is what generation 2 Bosch system does,but much more cleverly and seamlessly than that which we could achieve. Also I just could not contemplate the conversations with potential customers to explain the procedure necessary and also expect customers to go through this procedure and keep momentum going and not wobble whilst going through the sequence.
We decided to convert all our stock of TCM crank drive plus derailleur bikes to crank drive plus Nuvinci hub,it totally overcame the problems,the gearchange is now super smooth,but the decision was a £20k investment.
We found that you could execute reasonable gear changes with TCM plus derailleur but you had to be slick and precise with the procedure-if you got out of sequence or just were lazy and committed power on changes the derailleur made awful graunchy noises and inevitably damage was caused,once such damage occurred the derailleur was effectively useless and we were constantly replacing derailleur parts.
My conclusion is that the current level of design for TCM plus derailleur is not acceptable and should be avoided until R & D sorts out how to release the load on the chain without losing momentum,as these design considerations are contra I just cannot see a way of overcoming what is a basic design flaw,hence the reason why us and many of the large manufacturers have reverted to hub drive,the emergence of the BPM motor was a happy coincidence.
My Chinese supplier has one engineer who for a year now has experimented with all sorts of combinations and offsets derailleur,him and I came to friendly blows at Shanghai. On the flat he has improved things,but uphill standing on the pedals with max PAS it still sounds like the derailleur is hell bent on destroying itself.
IMHO,the design combination is basically flawed-however as Porsche proved throw enough money at a bad design and you can make it work!
Now I'll put my flak jacket on!
KudosDave

 

[Artstu]

The Kudos e-bike supplier is one of the largest bike manufacturers in the world,they have very impressive R & D facilities,

Clearly not that impressive.

We all tried without success,with many combinations of offsets,gear types to overcome the graunchy gearchange problem.

I'd like to think you know you're looking at the wrong end. A system that responds instantly to your pedal pressure like the Bosch is needed.

We decided to convert all our stock of TCM crank drive plus derailleur bikes to crank drive plus Nuvinci hub,it totally overcame the problems,the gearchange is now super smooth.

So the Nuvinci will change under full load perfectly with no issues?

My conclusion is that the current level of design for TCM plus derailleur is not acceptable and should be avoided until R & D sorts out how to release the load on the chain without losing momentum,
KudosDave

That was obvious to anyone who had ridden the crude run on of power most systems use, instant response and proper torque sensing are required.

 

[pedelecvirgin]

So can I simply , exchange (if I could get hold of one) a 26 inch wheel with a nuvinci hub installed, for my 26 inch wheel with derailleur? Plus associated cables and shifters. And if so at what cost?

pedelecvirgin

 

[Deleted member 4366]

Though not ideal, the run-out on your gears is fairly normal on free-wheel gears. It probably helps gear-changing rather than hinders it.

 

[peerjay56]

So can I simply , exchange (if I could get hold of one) a 26 inch wheel with a nuvinci hub installed, for my 26 inch wheel with derailleur? Plus associated cables and shifters. And if so at what cost?

pedelecvirgin

Yes. Not a cheap option, mind.

 

[Deleted member 4366]

They're about £300, but then you have to get a rim and spokes and get it built, so about £400.

 

[JohnCade]

£400 would get you a lot of chains sprockets and mechs.

 

[Kudoscycles]

So can I simply , exchange (if I could get hold of one) a 26 inch wheel with a nuvinci hub installed, for my 26 inch wheel with derailleur? Plus associated cables and shifters. And if so at what cost?

pedelecvirgin

Please read your PM.

 

[trex]

some of the tricks that I have tried changing gears on hills with Woosh CD bikes:

1. before changing gears, stop pedalling and keep the throttle to maximum - the Woosh will happily oblige.
2. stop throttling, wait for the motor's noise to die down, change gear
3. rev up again, the motor will re-engage at the minimum load level and performs the shift for you, you can hardly hear the gear change

It calls for accurate timing but because you only need to concentrate on throttling, it's quite easy to get the knack. Start pedalling again after the gear change is over.

 

[John F]

some of the tricks that I have tried changing gears on hills with Woosh CD bikes:

1. before changing gears, stop pedalling and keep the throttle to maximum - the Woosh will happily oblige.
2. stop throttling, wait for the motor's noise to die down, change gear
3. rev up again, the motor will re-engage at the minimum load level and performs the shift for you, you can hardly hear the gear change

It calls for accurate timing but because you only need to concentrate on throttling, it's quite easy to get the knack. Start pedalling again after the gear change is over.

Exactly - it's that easy really after you've done it a good few times.Don't know what all the fuss is about!

I used to think that changing gear was a right challenge to do smoothly, when I was learning to drive a car. Now it's no problem!

 

[Artstu]

We decided to convert all our stock of TCM crank drive plus derailleur bikes to crank drive plus Nuvinci hub,it totally overcame the problems,the gearchange is now super smooth,but the decision was a £20k investment.
KudosDave

So the Nuvinci will change under full load perfectly with no issues?

Can you answer my question Dave please? or is your lack of a response to my question an indication that it won't actually change gear under full load?

 

[dmsims]

some of the tricks that I have tried changing gears on hills with Woosh CD bikes:

1. before changing gears, stop pedalling and keep the throttle to maximum - the Woosh will happily oblige.
2. stop throttling, wait for the motor's noise to die down, change gear
3. rev up again, the motor will re-engage at the minimum load level and performs the shift for you, you can hardly hear the gear change

It calls for accurate timing but because you only need to concentrate on throttling, it's quite easy to get the knack. Start pedalling again after the gear change is over.

I'd like to see that on the 420 ft ascent I did yesterday - I actually counted and changed gear 10 times. On the CD you simply come to a dead stop

 

[Deleted member 4366]

Can you answer my question Dave please? or is your lack of a response to my question an indication that it won't actually change gear under full load?

I'll answer it for him because I have a Nuvinci on my GNG crank drive, which is a lot more powerful than the Kudos TCM unit. It has about double the torque.

You cannot get crashing gears anymore because there's no gears to crash. It's a CVT unit.

The higher the load on the chain, the more effort you need to twist the changer. You can still change under maximum power, but if you have any sympathy for the change cables, it's better to reduce the load on the chain a bit to reduce the strain on the change cable.. That's with the GNG. The effort to change will be less on the Kudos because it's only 250W.

 

[Artstu]

Thanks Dave, I had thought it was something like that. At least there's a bit less to think about with that hub, a dab of the brake, change ratio, and then wait for the power to kick in, still not ideal, but a step in the right direction.

 

[mike killay]

Just for the record.
I have removed the pedal sensor from my Tonaro Enduro and it is now throttle only.
Changing gear uphill is simply a matter of closing throttle, the motor instantly dies out, pedal lightly and change gear, re-open throttle, the motor instantly responds.

 

[Kudoscycles]

Artstu....to answer your question.

Changing gear with the Nuvinci is completely silent and no more effort than turning a knob. It does not require any chain lifting so the load on the chain is irrelevant.
If you google Nuvinci 360 their website clearly explains the operation.
Having had a peek at the internals I think it would probably accept a lot of power.
It is 1.2 kg heavier than the Shimano derailleur system.
The only real downside was price.
We looked at using the Shimano Nexus 8 hub but to ensure reliability we would have had to engineer some means of reducing the power on power on gear changes,with the Nuvinci that is not necessary.
Please Be a bit patient with your questions,I am busy on many other projects and not always attached to a computer-you did jump to the wrong conclusion.
KudosDave

 

[Artstu]

It does not require any chain lifting so the load on the chain is irrelevant.

Misleading given d8evh's comments below. Thanks for replying though.

The higher the load on the chain, the more effort you need to twist the changer. You can still change under maximum power, but if you have any sympathy for the change cables, it's better to reduce the load on the chain a bit to reduce the strain on the change cable.. That's with the GNG. The effort to change will be less on the Kudos because it's only 250W.

 

[Kudoscycles]

Artstu.....D8veh bike is a special build with more power....I rode the Kudos Eiger with Nuvinci at Redbridge....changing the cone ratios is no more effort than turning a throttle....the bike does take a little getting used to....it is easy to overchange on the gearing- by that I mean that you can go from very low gear to top gear so easily that there is a tendency to make dramatic gear changes,when first riding the bike,or to go too low,it requires a feel to make small changes,but you soon get used to the feel.
I am sure you are aware that the Nuvinci display shows a mountain display for low gear and a flat line for high gear.
Also i have found that with the TCM crank motor it is better to be in a higher gear on steep hills,the motor seems to respond to having load upon it,despite I am assured that it has a speed sensor not a torque sensor.
To be honest I think the best use of the bike is in traffic,the gear changes are so easy and smooth,a great commuting setup....if I was buying a bike for sport/hill climbing usage I would use a hub drive with BPM motor,the low speed grunt of the BPM has very satisfying torque.
KudosDave