The no load speed is always much higher than the on road speed. For example the Torq 1 unloaded will do over 17 mph but barely 15.5 mph on the road. But the speed will be different for different people, weight, air resistance etc. I was originally told the 160 rpm version for a 700c wheel. I was also told that the 160 rpm had 'reliability issues' so it is better that you went to the 175 rpm version anyway.
Trek Cytronex - First Impressions.
- Thread starter Chris_Bike
- Start date
I don't think you've caused any trouble at all Chris, but it's right for others to question and crosscheck apparently surprising results and no-one should be sensitive about that.Hello everybody........ Oh dear, I do seem to cause so much trouble
Chris
Like John, I'd like to know who Mark is casting aspersions at with his references to knockers and others in the industry. What others, I've seen none posting, and I don't regard anything said in the threads as knocking?
The Cytronex appears to be a fine product and there's certainly a very great need for products like this to fill what has been a glaring gap in the market for a long time. But that doesn't mean to say it will just be nodded through without examination.
You know the old saying about the heat in the kitchen Mark.
Be assured that if your product passes muster it will have a very bright future.
.
That was as the owners saw it originally John, and they wasted money changing the rider gearing in many cases.
It's real problem went deeper though as I argued at the time. It was a motor meant for a 20" wheel placed in a 28" wheel and so geared up by 40%, far too much. It gave it high speed but lost all the motors torque and thus climb ability.
In Tongxin terms it would be like the Cytronex using the 260 rpm motor instead of the 175 with similar damaging results.
.
Yes that's a rubbish number Chris. I don't bother with these calculators and work it out myself always. I make it 640 watts.
N.B. Figure amended since I'd taken the speed as 10 mph from Chris's earlier post.
.
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I understand it refers to the maximum speed of the motor under a typical load
Ditto on John and Flecc's points on specific comments and posters that you object to, Mark.
Frank
Chris,
I'd felt the same way as Flecc and Stuart. I would expect that as a lifelong cyclist you have good cycling technique, have developed the right muscles and have the confidence to attempt a steep hill that would set you apart from the vast majority of the population, even people half your age. It's not that you are necessarily a lot fitter than you think, just that the average person is a much less effective cyclist than you perhaps realise!
By comparison, when I was younger I did a fair bit of rowing. I've not done it now for over 20 years, but when I go into a gym and see non-rowers using an Ergo, I can usually major spot flaws in their technique just from watching a stroke or two. The odd time I've jumped on a machine, I have still been able to row much more efficiently than fitter people with poor technique.
One point that I noted from Mark's comments and initial website is that it does strongly emphasise that this is a bike for people who do want to pedal - I felt that not only did he know his market but was trying to make it clear to potential buyers to avoid the Torq-type pitfalls.
Conveniently, 15mph on a 15% slope is about 1 meter/sec vertical velocity. To maintain that velocity against gravity requires approx 10W/kg, so I would say 729 Watts for Jack and his bike is about right (including rolling and wind resistance)
Mark, with respect and in all fairness no comments have been aimed at your bike, but at correcting the potentially misleading impression being given by a rider unintentionally underestimating his fitness. I hope that you see that as a positive, avoiding potential disappointment for your customers and there is no suggestion here of your product being slighted in any way: on the contrary, if you re-read you'll see that many comments go out of their way to be highly complementary, and that hasn't happened often here recently!
and I wish you every success with your product.I don't question the first part, and would always recommend test-rides here possible in similar terrain to the intended use. Asking people to judge aspects such as range and hill-climbing, which depend so much on an accurate assessment of the rider's fitness, from reviews can be very misleading though, as has been seen too many times.
You have repeatedly sought to dismiss the opinion of anyone who hasn't ridden the bike by implying that its impossible to judge the bike's performance without riding it, but that simply isn't true and as I said earlier in the thread the only accurate way for readers is to evaluate the bike and rider output separately, and then add them together.
May I suggest as an idea that, to address this issue in future and help your customers choose, you consider putting together a simple table or guide which gives a clearer indication of what riders of differing fitness levels might achieve with your product.
Regards, Stuart.
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I don't usually bother with calculators either, and got 800W from my own figures for Chris (14.5 stone) plus cytronex (17kg) on a 15% slope at 10mph.
The calculator John posted comes up with exactly the same figure, with lowish roll resistance (0.07) & average frontal area coefficient ('straight arms' 0.004).
A lighter rider and bike, less resistance, lower speed and/or shallower gradient would obviously need less power, and the calculated power level for Jack's data (total weight less than 60% of Chris & cytronex) for the same slope & speed is 460W at 10mph, 411W at 9mph and 364W at 8mph, so about 8mph on that gradient is exactly in line with what the outputs from his tests suggest.
Stuart.
The calculator John posted comes up with exactly the same figure, with lowish roll resistance (0.07) & average frontal area coefficient ('straight arms' 0.004).
A lighter rider and bike, less resistance, lower speed and/or shallower gradient would obviously need less power, and the calculated power level for Jack's data (total weight less than 60% of Chris & cytronex) for the same slope & speed is 460W at 10mph, 411W at 9mph and 364W at 8mph, so about 8mph on that gradient is exactly in line with what the outputs from his tests suggest.
Stuart.
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I'm a slave to my science - or more boring experimental data
It did stop raining, so I went out to test the computer on a RTTC 10 mile time trial course that runs locally. I also decided to test the range of the bike in high power mode. So, Like yesterday, I left the power on throughout the ride, but this time at high power.
First of all, the computer.......... This overestimates distance by about 3% so, if anyone wants to, they can correct all my posted results by 103/100. Frankly, I won't bother and I'll carry on reporting what the computer says.
So, on high power I rode at an average speed of 15.9 mph (max 28.2) and the battery died at exactly 22 miles.
I'm looking forward to another flurry of emails praising my athletic prowess. Please don't think that I don't appreciate them but I note that all the posts so far have been from chaps. Aren't there any female pedelecers out there that want to send me fan mail?
On the watts front, Flecc has sent me his calculation, which I understand perfectly. What I don't understand is why some of the calculated power requirements are so much higher than any athlete can actually deliver. I am temped to contact the British Team to tell them not to bother going to Beijing because they won't be able to get up the hills, but perhaps I'll delay for the moment.
Happy cycling everyone,
Chris
It did stop raining, so I went out to test the computer on a RTTC 10 mile time trial course that runs locally. I also decided to test the range of the bike in high power mode. So, Like yesterday, I left the power on throughout the ride, but this time at high power.
First of all, the computer.......... This overestimates distance by about 3% so, if anyone wants to, they can correct all my posted results by 103/100. Frankly, I won't bother and I'll carry on reporting what the computer says.
So, on high power I rode at an average speed of 15.9 mph (max 28.2) and the battery died at exactly 22 miles.
I'm looking forward to another flurry of emails praising my athletic prowess. Please don't think that I don't appreciate them but I note that all the posts so far have been from chaps. Aren't there any female pedelecers out there that want to send me fan mail?
On the watts front, Flecc has sent me his calculation, which I understand perfectly. What I don't understand is why some of the calculated power requirements are so much higher than any athlete can actually deliver. I am temped to contact the British Team to tell them not to bother going to Beijing because they won't be able to get up the hills, but perhaps I'll delay for the moment.
Happy cycling everyone,
Chris
Depends on the duration of the climb Chris. The legendary Miguel Indurain on a climb of La Plaque during the 1995 Tour de France expended a calculated continuous 450 watts for exactly 1 hour, an extraordinary output for that duration, but some top riders like Lance Armstrong are reckoned to be able to peak at over 1000 watts briefly.
This 71 year old produced a calculated 362 watts briefly a few months ago when hill climbing, but doesn't make a habit of it.
Nasa cycling output figures for healthy males (not athletes) are:
300 watts for about 10 minutes continuous.
200 watts for about 1 hour continuous.
100 watts for about 5 hours continuous.
Skilled sporting cyclists following a normal training regime will add considerably to those, probably at least 50%.
.
Agreed Flecc. I can remember Indurain on La Plagne - interestingly he broke all the rules for climbers by being huge and pushing enormous gears on the hills. Armstrong was a more "normal" climber (after his recovery form cancer) but his brief bursts of 1000W aren't really what climbing is about (though if you can do it it's a good way to shake off wheel-suckers!).
What is bothering me is that top climbers go up 20+Km hills (!) like Ventoux or Alpe d'Huez at 12-15 mph (in 40 degees, but that's another issue). On the basis of these sort of calculations, they shouldn't be able to!
What is bothering me is that top climbers go up 20+Km hills (!) like Ventoux or Alpe d'Huez at 12-15 mph (in 40 degees, but that's another issue). On the basis of these sort of calculations, they shouldn't be able to!
Yes, there are sometimes some puzzling discrepancies, though some bodies seem to measure up to extraordinary things. Little Marco Pantani springs to mind!
I think to some extent the equations could be based on designer needs for ordinary mortals, and when standard factors like the 9.81 I mentioned are included, oddities can arise at the extremes of the included numbers.
.
In case you missed my last post Chris, there isn't a problem with those figures: they correspond with the NASA figures flecc posted and Jack's test results - around 300-450W for 10 minutes or so being normal for an athlete
Assuming those climbs average around 6-7% or so at most, at those speeds, again it is within an athlete's limits from the calculations.
I know people often dismiss figures and stats as inaccurate, and that that can become habitual, but in these cases, and correctly used, the calculations can be fairly accurate and helpful.
Stuart.
PS I hope the facts & figures given clarify the impressions in this thread. If the facts or figures are otherwise then please correct them.
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To try to get this back on track (again). I think I should have noted thet the range that I have achieved on the last two rides is considerably higher than I recorded when I first got the bike. This could, of course, be a consequence of improvements in my already legendary athletic prowess........ I think the explanation is more mundane - having taken the battery through several charge/discharge cycles I suspect it is now working at maximum efficiency.
The mundane expanation is true without doubt Chris. The first two or three full charge/discharge cycles of NiMh bring it to initial full capacity, but the capacity then continues to increase very sightly over roughly the first 100 charges. Thereafter the capacity starts a long very slow decline until it becomes inadequate for the purpose.
However there's a further possible reason that's often missed on new e-bikes, the fact that as you use it and learn the way it reacts, you will unconsciously change some aspects of your usage to get the best out of it.
.
just tried posting a reply and the computer went crazy, turned out something was resting against my other keyboard and I posted some gobbledygook, sorry!
What i wanted to say was, I've just read an e-mail from Mark that my bike is going to be ready today, I'm so excited, tempted to take time off work to collect over the weekend but reality dictates that I must wait until we sort out dispatch by courier.
I've been glued to this forum since Prestigne, hope to add useful info when I get on the road.
All the best
Mike
What i wanted to say was, I've just read an e-mail from Mark that my bike is going to be ready today, I'm so excited, tempted to take time off work to collect over the weekend but reality dictates that I must wait until we sort out dispatch by courier.
I've been glued to this forum since Prestigne, hope to add useful info when I get on the road.
All the best
Mike
For professional athletes, you have to factor in illegal steroid use, blood doping, er, high altitude training, peak athletic condition that is probably not attained during routine measurements but would be during an important competition in all your calculations.
I'm only half kidding, too
edited, oh, weather, humidity temp all big factors I would guess in actual records
I'm only half kidding, too
edited, oh, weather, humidity temp all big factors I would guess in actual records
C
Cyclezee
Guest
I got a message from Mark yesterday to say my bike would be ready Saturday, so I will be driving down to collect it.
Unfortunately, I but won't be able to give any sort of meaningfull report for a while as I still have my right hand in a splint and won't be able to ride again for a week or two.
J hn
Unfortunately, I but won't be able to give any sort of meaningfull report for a while as I still have my right hand in a splint and won't be able to ride again for a week or two.
J
hnI bet you will be out on it splint or no splintI got a message from Mark yesterday to say my bike would be ready Saturday, so I will be driving down to collect it.
Unfortunately, I but won't be able to give any sort of meaningfull report for a while as I still have my right hand in a splint and won't be able to ride again for a week or two.
J
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