Questions
I will answer your questions because I think they are good well intentioned ones. However, I won't be such a regular contributor for the rest of the week due to the number of orders to deal with!
1. Firstly I can honestly say no, I have not had a single controller failure. I am a businessman who happens to have an environmental conscience, and if I had experienced problems I would have ditched the technology a long time ago.
2. Six.
3. 500 on average before we changed to a new generation of prototype. The only trouble we have had is with lithium batteries (that we shelved), and some dodgy connections in the early prototypes. These were down to my own inept soldering as opposed to the military specification crimping tools and waterproof connectors we use for production.
4. We generally don’t bench test because we prefer to test things in the real world. We did however test the stall current cut out by rigging up a bike with the brake on and increasing braking. We managed to wear down some brake blocks and cause a nasty smell but we did not succeed in burning out a controller, it simply cut out each time when it reached the limit of 15 amps. Another relevant example is the Presteigne hill climb. I have already described in this thread what happened, but what is important is that I used a stupidly fast motor thinking the hill climb was half a mile and it turned out to be a mile and I still came third. So for half a mile of steep hill the motor was doing about 2/3rds of the minimum speed it wanted to be doing - and despite this I had no problems.
We have been genuinely baffled by the questions we have had about reliability in this forum as this has not been our experience at all. Our best guess is as follows:
The Schwinn bike used a Pedelec function which we dismissed out of hand. We found that the pedal sensors were appalling pieces of tat and chucked them straight in the bin (well actually, the recycling bin). Also the way this works with power lurching in and out is crazy. We want the user to be in control and have power when they want it which is why you press the button and get full power (or the slower speed if you want) and it cuts whenever you press the brake. We have had a superb experience in this way.
However, we have only used the bike from standstill accidentally. We stipulate that 5mph is the minimum speed, and preferably slightly higher. This is because we know that a sensorless motor does not perform well from zero and also because there is a huge waste of energy starting from zero which is unnecessary on a proper bike. I think, and I must admit I can't be certain, that our experience with the system is down to two things: firstly the way our system works and secondly because we always use the system at a sensible speed. Doing this we have had thousands of trouble free miles and also developed a fantastic form of transport which is a great deal of fun.
It is still possible to do a hill climb by putting the bike in third gear, ensure you are in ‘slow speed’, setting off under your own steam then pressing the boost button once you are moving and finally selecting fast speed once you are doing something like 7mph. However Cytronex has been developed to get people from A to B fast and if they wish, without too much exertion (otherwise they just get there faster). It is an efficiency based transport solution. It is not designed for people who don’t want to pedal (although technically this is possible) and being a light weight bicycle which is also a very nice ride without the motor, there really is no reason to use it from zero mph. I think those who don’t want to pedal should probably look elsewhere, but for those who enjoy cycling, Cytronex really is a fantastic experience!
