Kudos-KTM Roadshow,Manifold Trail,Derbyshire,April 13,12.00-17.00
- Thread starter Kudoscycles
- Start date
I agree with you although bike style choice is a very personal thing - however I'm looking strongly at other KTM Bosch bikes and my favourite remains the Macina HS 400 which has SRAM Dual Drive 8F gears (8 derailleur plus 3 in the rear hub = 24 total).
('KD's price list shows this with Shimano Deore LX 9-speed but maybe that's not the same bike I've been looking at.)
Taff - I was referring to the Bold having a torque sensor only because that's what I thought I had been told at the time but faced with so many bikes it's easy for confusion to set in.
I can't for the life of me see any reference to that in the KTM listing;
KTM Bikes // Bikes vom Besten!
This one's in German which doesn't help me much;
KTM e-Bikes 2013
JimB
So do you think it's a 'technique' type thing?
Did you think it was a 'torque/sped sensor' bike?
Just done the maths on that one and actually both hills are very, similar.
Second hill is 7% average but if you take out the continuous ascent and calculate that it's 10.7%.
I know what you mean
D
Deleted member 4366
Guest
Never believe salesmen. Many of them don't have a clue.
Whether you have a speed sensor or torque sensor, how the power is handled depends on algorithms in the controller. Most are very smooth and have ramps to smooth out transitions. The Bosch bikes ramp down the power when you get to the 15mph speed limit, so you don''t feel any transition, and they ramp it up when you start pedalling. Other bikes like the Kudos Ariba have a much shorter ramp (if any), and simply switch off when you get to the speed limit, so you feel it, and until you're used to it, it feels like a faulty connection is cutting power. You can avoid this by increasing the speed limit in the LCD display up to 40kph to where the motor power ramps down more naturally. The new Woosh Sorocco CD is the same - and many others.
I think JIMB has the answer to why you stalled out. Crank-drive motors generally don't have as much torque as hub-motors, so you have to change down the gears to get the torque at the back wheel. If you don't change down, they soon stall out - just like what would happen without an electric motor. For a 10% hill, I have to go down to first gear with a Bosch motor. Hub-motors make the same torque regardless of which gear you're in.
To be correct, the Bosch motors have both torque and speed sensors.
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You're absolutely right. I didn't say that because I thought I would be talking rubbish but the motor did almost come to a full stop - I initially thought the battery had gone until the light bulb lit up in my head - an increasingly rare occurrence!
JimB
I think it was probably just the gears not changing, I have an 8-speed nexus, and a slight pause allows a change, actually it just needs a very slight lift of pressure. The Bosch needs a longer full pause to change. I think I would get used to slower gear changes.
Ah, after I'd posted I hoped no one would be able to check
it was less steep than I had remembered. I did the Butterton Climb on a Kudos with speed sensor, it felt quite lively, noisier and coped OK, reminded me of my Cyclamatic folder.Cool.
I can accept this but I'm certain I would have dropped the gears - it's the obvious thing to do.
I'm not an inexperienced rider in as much as I am often in the granny gear on my current MTB (which has almost identical cassette and chainring sizes) whilst climbing any hills around me. For example a short rise near me is 14% and I can struggle up that.
I never felt the 'bite' as I did with the other 3 bikes. Strange one this.
I think it'll most likely be hub drive for me.
Ha ha - gotcha.Ah, after I'd posted I hoped no one would be able to check
Wouldn't worry too much about that - these may well fit (at worst with a bit of trimming) - they're specifically designed to be compatible with bikes which have a front suspension fork, and either 26" or 28" (i.e. 29" to all intents and purposes) even if there's no attachment point on the front fork - you just use 2 cable ties.
http://www.amazon.co.uk/dp/B000X5ZK66/ref=asc_df_B000X5ZK6612816122?smid=A3P5ROKL5A1OLE&tag=hydra0b-21&linkCode=asn&creative=22206&creativeASIN=B000X5ZK66&hvpos=1o2&hvexid=&hvnetw=g&hvrand=11324805931285465459&hvpone=&hvptwo=&hvqmt=
D
Deleted member 4366
Guest
If you went on the Others first, they couldv'e lulled you into a false sense of security. The torque from their motors will drag you up regardless of pedal speed or gears. Maybe you were expecting the others to be the same , but the power would've just kept decreasing in the higher gear.
You still have a bit of misunderstanding about the sensors. All they do is send a signal to the controller to tell it that something's happening. It's the controller software that decides how much "bite" to give. the programmers can make it how they want: soft start or instant full power, or any other way. The more time and effort they put into it, the smoother everything works. The cheaper ones tend to have power on or off when the sensor (torque or speed) senses that you're pedalling. When you have a high-powered bike, you can notice the difference in software a lot more.
I think this is quite possible.
OK but 3 of them were KTM so I kinda figure you you might expect similar programming.
In any event, it has focussed me on hub drive and I'm happy to go with that.
D
Deleted member 4366
Guest
The KTMs with Bosch motors have the same Bosch system, i.e. motor, controller, sensors etc, which is the same as any other bike with a Bosch system of the same type. The hub-motored KTM has a completely different system.
I think I can explain the reason why some riders experienced a 'hit the wall' effect with the KTM Bosch powered bikes. Its not the fault of the rider,more the fault of the salesman-in this case me! But with so many different bike styles,so many different experience levels and so much happening in a short period of time it is difficult to communicate all the functions of the bike.
The Bosch system has in effect 3 sensors-speed,cadence and pedal torque,it receives an input from all 3 sensors and delivers the optimum power to efficiently propel the bike,
The primary sensor is the speed sensor,it has to be, to meet the requirement of EN15194 ie if you stop pedalling it will cut off the power. If you try to ride up a hill in too high a gear,or dont realise that the Nexus hub has not changed down(this will happen if you dont momentarily take load off the pedals) then inevitably you will reach a point where the pedal cadence will stop despite high torque still being applied and the power will cutoff.
The problem occurs because the salesman has not fully explained that the Bosch system is a torque-speed sensor system and does not easily cope with incorrect gear selection.
Stop the bike change down to first gear and put maximum load on the torque sensor pedal and the speed sensor will then detect pedal cadence and deliver max power,as the cadence rises it may then determine that less assistance is required but only if the pedal torque is reduced.
I suppose some could argue that it is too clever and that a simple speed sensor bike gives max power as soon as you turn the pedal is crude but very effective.
Hope that helps
KudosDave
The Bosch system has in effect 3 sensors-speed,cadence and pedal torque,it receives an input from all 3 sensors and delivers the optimum power to efficiently propel the bike,
The primary sensor is the speed sensor,it has to be, to meet the requirement of EN15194 ie if you stop pedalling it will cut off the power. If you try to ride up a hill in too high a gear,or dont realise that the Nexus hub has not changed down(this will happen if you dont momentarily take load off the pedals) then inevitably you will reach a point where the pedal cadence will stop despite high torque still being applied and the power will cutoff.
The problem occurs because the salesman has not fully explained that the Bosch system is a torque-speed sensor system and does not easily cope with incorrect gear selection.
Stop the bike change down to first gear and put maximum load on the torque sensor pedal and the speed sensor will then detect pedal cadence and deliver max power,as the cadence rises it may then determine that less assistance is required but only if the pedal torque is reduced.
I suppose some could argue that it is too clever and that a simple speed sensor bike gives max power as soon as you turn the pedal is crude but very effective.
Hope that helps
KudosDave
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And hence why some of us prefer Hubs. Far to much faffing about for my liking. Me and Taff went up the hill on Hub bikes and we got nowhere near bottom gear (think lowest I went into was 5th on the middle front ring).
If cadence and torque are measured then I don't know why manufacturers don't give you the option of selecting a preference like switching the torque sensor off or changing the percentage mix of the two. I have a conversion kit on my bike no torque sensor and it is effortless to ride. I had my heart set on a KTM Macina race but found it hard work compared with my bike. In fact most times I've ridden a torque sensor bike I say to myself I thought this bike was supposed to be electric! I find with the torque sensor when I push hard on the pedals you get some power, but when you have achieved the required speed you ease off the pedals slightly and the power has gone and your riding an unpowered bike even on the highest setting. I must be missing the point or doing something wrong!
Unlike what I've read about the Panasonic crank-drive where easing off gives more power, the Bosch only helps you when you increase your effort. I prefer it that way, but as you say the Bosch does feel like an unpowered bike with very little kick. It must be good for extending the battery range.
Not so, this issue is often confused. The Panasonic torque sensor gives more power for more pressure in exactly the same way. Where the confusion can arise is that the earlier Panasonic units were also dependent of the pedal cadence, full power only available up to 40 crank turns per minute and gradually phasing down from that. As long the gear is chosen in relation to road speed to keep the pedal cadence below 40, full power is always available.
From 2010 Panasonic units, that early decline in power with cadence was removed, full power now available through to almost 15 mph.
So basically the purpose of a torque sensor is to increase the range and make the bike harder to ride! I prefer my cheapo kit where I'm getting lots of power all the time and if I pedal harder I can see the current come down or the speed increase.
D
Deleted member 4366
Guest
Whether you have a torque sensor or speed sensor, it makes no difference to power. The sensors only detect how you're pedalling. It's the controller that decides how much power you get, and you can program it to make the power in any profile.
Torque sensors have the advantage of instant detection so that you don't need brake switches. There's always a delay with speed sensors for both power on and power off.
A lot of the complaints with the various bikes power or behaviour comes from either not understanding how it works or not using it properly. If it was your own bike, you soon find how to get the most out of your system. In my experience, they all have advantages and disadvantages that tend to cancel each other out.
Torque sensors have the advantage of instant detection so that you don't need brake switches. There's always a delay with speed sensors for both power on and power off.
A lot of the complaints with the various bikes power or behaviour comes from either not understanding how it works or not using it properly. If it was your own bike, you soon find how to get the most out of your system. In my experience, they all have advantages and disadvantages that tend to cancel each other out.
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