MattH
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my nephews bike is rated for 10kw continuous, cost about £1500 all in.
(there's a big jump from a bike that can do 10kw for a few seconds to one which can do it continuously, if you only want 10kw for few seconds then 2kw the rest of the time you can probably do it for £1000 (and the rest of the bike still be decent))
(there's a big jump from a bike that can do 10kw for a few seconds to one which can do it continuously, if you only want 10kw for few seconds then 2kw the rest of the time you can probably do it for £1000 (and the rest of the bike still be decent))
Which pro team were you riding for?
Average road race bike cyclist is about 17-18mph on the flat. Pro tour on flat stage peloton speed averages about 25-28mph.
All I know is as well as soon as you get the road race bike out and put the kit on you are in far more danger than a regular cyclist.
Burdekin
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Which pro team were you riding for?
Average road race bike cyclist is about 17-18mph on the flat. Pro tour on flat stage peloton speed averages about 25-28mph.
All I know is as well as soon as you get the road race bike out and put the kit on you are in far more danger than a regular cyclist.
As an ex roadie I thought the same. Pretty decent to do 24/25mph for a 40k time trial.
Yeah and with time trials you are on a specific bike with the end goal of using all your energy at the point of crossing the line. Unlikely you will be stopping for junctions etc. A lot of the time trials around my area tend to have the flattest sections of roads - even dual carriage ways in them.
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Have you ever checked your bike computer against a gps app?Depends on how you calculate 'average' and over what distance
For instance, on a mountain bike with slicks I know (my little computer said so) I can average about 25mph, on the flat, over about 5 miles or so.
Alternatively, I can look at a speedo now and again and say "I've been doing that speed for ages, must be my average".
Knowing how hard it is to average anything like that on a road bike you've either got extremely good legs or an extremely generous speedo.
My best over a fast 10 mile TT course is just over 23 mph, yesterday on a "pleasure ride" I averaged 18.7 mph over 15 miles.
Pro tour average speeds are a bit misleading because they generally pootle along for the first 100K's and then start racing properly.Which pro team were you riding for?
Average road race bike cyclist is about 17-18mph on the flat. Pro tour on flat stage peloton speed averages about 25-28mph.
All I know is as well as soon as you get the road race bike out and put the kit on you are in far more danger than a regular cyclist.
Not a pro rider by any stretch, but I used to be stupidly fit before I got my driving license (I was late in life passing my test) because I cycled everywhere. I started out on a racer and averaged 12,000 miles a year because I rode it every single day.
I had a decent cycle computer that was calibrated to my wheel size and a cadence sensor on my crank, perhaps average was the wrong word to use, to clarify I would spend the majority of time riding at 24mph or faster apart from stopping at lights and junctions etc a cadence sensor is a lot more use than just a plain speedo because you can use it to ensure you pedal efficiently.
I had some fun one time when I was riding along and started passing riders with numbers on their backs, turns out there was a road race going on and I spent the next 9 miles passing riders until they went a different direction to where I was going, I deliberately rode hard on that bit just to annoy them because I just wore a normal T-shirt & lycra shorts rather than their swanky replica pro team gear
Which just proves my point about a 15mph limit on the pedal assist mode being stupid.
pedrobedro
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Do any of you live in the sort of terrain we have in Derbyshire. I'm lucky to average 11mph round here, partly because I'm old and get out of breath but mainly because we have a lot of hills and the downhills don't make up for the uphills.
me, I ride for pleasure and I used to comfortably average above 15mph for an hour or two, but I know what you mean, I'm the exception rather than the norm and that was I used to live in Lancashire which is a lot flatter than around here (North Wales)barracuda816
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^ thats a bit better than the norm around here! 
Pro tour average speeds are a bit misleading because they generally pootle along for the first 100K's and then start racing properly.
Not a pro rider by any stretch, but I used to be stupidly fit before I got my driving license (I was late in life passing my test) because I cycled everywhere. I started out on a racer and averaged 12,000 miles a year because I rode it every single day.
I had a decent cycle computer that was calibrated to my wheel size and a cadence sensor on my crank, perhaps average was the wrong word to use, to clarify I would spend the majority of time riding at 24mph or faster apart from stopping at lights and junctions etc a cadence sensor is a lot more use than just a plain speedo because you can use it to ensure you pedal efficiently.
I had some fun one time when I was riding along and started passing riders with numbers on their backs, turns out there was a road race going on and I spent the next 9 miles passing riders until they went a different direction to where I was going, I deliberately rode hard on that bit just to annoy them because I just wore a normal T-shirt & lycra shorts rather than their swanky replica pro team gear
Pro tour average speeds aren't misleading really especially on non mountain stages. Let's not forget there is no stopping at junctions as well.
Look at the tour of flanders last weekend you couldn't say there was any pootling. Also many flat races without serious climbs or at least serious climbs near the finish end up being a race of teams with prime sprinters ensuring any breaks don't get too far away.
La vuelta 2016 perhaps (the best grand tour I can remember for many years) was a fantastic case of pressure right from the start of races - break after break. Team sky with all their hopes of controlling it had no chance which was refreshing.
Cadence sensors I am pretty familiar with unfortunately. They serve as a great example of aging back in the mid 90's I know the cadence I used to run now days being 20+ years older with knee problems I have to run a lot lower cadence. It's not as efficient but my knees simply can't take the higher rpm anymore.
julianthegypsy
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A friend of mine has a cycle repair shop and has built loads. You can take any bike you like and fit a hub motor to it. The one he uses every day has a 500watt motor, The extra is really useful for going up hills rather than extra speed. That's where the average speed goes up most anyway, I'd also fit regenerative braking and a a supercapacitor bank too to capture the energy when you hit the brakes faster than the battery could absorb it. If you're doing 12 miles a day, it'll only need charging every couple of days, but you could always put the battery on charge at work. No need for two battery packs.
Burdekin
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And for a bit of reference of how 500watts compares:
The lab tests undertaken by Froome show the 30-year-old has a peak power of 525 watts, and sustained power – between 20-40 minutes, of 419 watts. At his 2015 Tour weight, Froome's watts-per-kilogram would be 6.25w/kg.
So lose some weight, pedal a bit and blow the TDF winner away. ;-)
Wendelspanswick
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Be interested in what make of hub he uses, whether it's a branded one or a generic eBay hub.
normspanners
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I think a lot can switch down to 250w if 'needed'
I would think the more power the more efficient they will be too with the higher voltage.
Those Stealths Bombers are awesome bits of kit the acceleration is very good I saw them at a show 5-6 yrs ago. there was talk of the army getting them, to move troops fast and quiet, all you would need would be spare battery packs dropped of by helicopter a bit extreme for your misses though coz the fuel for the copter would be a bind...
I would think the more power the more efficient they will be too with the higher voltage.
Those Stealths Bombers are awesome bits of kit the acceleration is very good I saw them at a show 5-6 yrs ago. there was talk of the army getting them, to move troops fast and quiet, all you would need would be spare battery packs dropped of by helicopter a bit extreme for your misses though coz the fuel for the copter would be a bind...
most controllers have regen breaks, even the cheap ebay ones
with lithium iron batteries charging from regen breaks isn't an issue
nephew bike has 3p18s so it's 3 cells in parallel, and 18 of those in series
72v and 15ah... but they're good for 50c peak and 25c continuous discharge... that's 750 amps peak and 375 continuous...
charging is 5c continuous (75amps) - not sure on peak
they might be a bit generous with their ratings... but whatever the real rates are they're massive overkill, that's 54kw peak and 27kw continuous discharge and 5.4kw charge
with my old bike, at 2kw if you pulled away giving it power and pedaling at the same time you had to lean right over the handle bars so it didn't pull a wheelie
(to be fair it was set for hard start, so it was 2kw instantly... most start more gently and work up to max power)
has he got any build videos??
Burdekin
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Not that he's sent me, just pics along the way. Pretty much what is in his thread. He's making a battery pack for someone at the moment. An old video of his big wheel bike he made years ago:
