I had a quick razz on a spesh hardtail ebike at the weekend and (admittedly I think it might have been set on maximum) was surprised how much oooomph it had pulling uphill.
It did make we wonder if the sort of speeds that it could help achieve would be enough for me to win a World Cup round?
I’m usually a mincer, 15 miles in 2 hours round Calderdale so it would be all motor and not much in the legs.
How would my achievable speed and time compare to a top flight XC racer?

Do you have the technical skill of a top flight XC racer?

Chris Froome averaged 400W on a TdF climb. A e-bike can be up to 250W so you’d need to produce 200W+ to make up the weight deficit if an XC pro can produce similar power in a short burst.

They don’t hang about downhill though!

Do you have the technical skill of a top flight XC racer?

No

Do you have the technical skill of a top flight XC racer?
No

That may cause issues.

Chris Froome averaged 400W on a TdF climb. A e-bike can be up to 250W so you’d need to produce 200W+ to make up the weight deficit if an XC pro can produce similar power in a short burst.

But XC is much more bursty, I’d expect they’d be doing 800w+ for a 30 second burst.

chiefgrooveguru – Member
Chris Froome averaged 400W on a TdF climb. A e-bike can be up to 250W so you’d need to produce 200W+ to make up the weight deficit if an XC pro can produce similar power in a short burst.

Isn’t it all about W/kg.

An ebike alone probably weighs more than an WC racer and their bike…

Not exactly an ebike but a bike with a hidden motor being ridden by Dan Lloyd over a hill that he had won a few years previously as a pro rider.[video]https://www.youtube.com/watch?v=Wv5F5N6mFf0[/video]

Not a chance!

Think may be an issue for you…

Besides technical skill the other thing that really matters is your (VO2+Epwr)/kg a smaller rider will get much more advantage from those extra Watts than a lardy one.
The truly hidden and quiet systems areprobably limited to about 100W, but that is enough to propel a trim higher end sports rider into winning elite level.
In terms of truly answering the OP, ride the ebike around a world cup circuit and see what your time is.

Then do it another 6 or 7 times and see your total time.

If the course was mainly made of easy uphills and no technical parts then probably. Anything else and no as your lack of skill would challenge you and lack of fitness would let you down after a short time of moving around a heavy bike..

Obviously, the technical skill wasn’t the point I was asking about, more so the assistance available from an ebike.
It just was quite startling the acceleration and speed up a climb on the one I tried but if that wouldn’t leave a pro-racer in my wake, then I’m even more in awe of pro-riders.
I need to take one out for a day and time myself on the climb up Cragg Vale and compare it to the TdF boys.

A e-bike can be up to 250W

1000w e-bike.

http://cyclotricity.com/stealth-1000w/

You might want to change the fork for an xc race…

Stealth? Their marketing people need a slap, that’s about the ‘e’est e-bike I’ve ever seen!

Extreme e-biking!
If you ever wondered whether or not you can de-restrict your electric bike to go faster than the usual 25km/h speed limit and use it off-road, oh boy you’re in for a treat! The ever so popular Stealth now comes in a new power boosted version allowing you cruise at 50km/h given it’s 48V 1000W system.

The UK/EU regulations dictate that an e-bike must not exceed the rated power of 250W to be road-legal. Which is not great news for the thrill-seekers, power hungry among us who want to have the occasional fun off-road yet still be able to ride sensibly and legally on-road. A purchase of the common high powered electric bike will come with its legal implications. On the other hand, the practicality of a road-legal e-bike means giving up the fun one could have off-road. So which do you choose?
Well one thing springs to mind

Not XC but an interesting comparison of speeds on the road. http://road.cc/content/feature/196199-e-bike-vs-road-bike-shootout-austrias-toughest-climb

I’d say answer is no.

Love the “no OP, cause you’re shite” classic STW responses on this thread. Classic, guys, classic.

There’s also some nicely measured responses too.. In short, the answer appears to be probably not, but maybe. Based on the level of e-assist available.

I’m 47 and really fat.
I have an ebike, its eu legal.
Its great, it lets me get out and enjoy myself with my friends.
But one of the young kids (20yo) in my group, who rides a 160mm travel fs bike can leave me for dead on every climb.
Also, when i was in my 20s I would have done the same.
So, I’d say no.

Do you have the technical skill of a top flight XC racer?

No

I dont think this should stand in your way, buy one register for an event and show them a bit of plucky Brit and get stuck in, its opportunities like this that shape your sofa.

Id be happy to provide sponsorship in the form of one free charge.

Love the “no OP, cause you’re shite” classic STW responses on this thread. Classic, guys, classic.

More the understanding of how hard it is to race/ride one of these courses. Even if you could hang on on the climbs this is what your faced with on the way down.



There was a very insightful interview with Jarred Graves when he was doing national level XC in the run up to EWS (so remember 4x winner, podium at a World Champs DH, EWS World champion) on a couple of courses he had to ride at and on his downhill limit to keep up or ahead of the fastest national guys (none were racing WC at the time) in order to stay just ahead on the climbs. It’s a really tough game, I’ve been lapped by a few guys who are WC/Olympic XC an they cruise past up, down or along.

I was overtaken by a guy on an e-bike yesterday, ME, I know, so I’m in the yes camp.

The guy on a motorbike does a good job of staying ahead of the field in WC XC races, so I guess it depends on the size of the motor 🙂

Any b or c lines?

More the understanding of how hard it is to race/ride one of these courses

Mike… we all know how hard it is to ride an XC WC course. The guys are mentally skilled. We all know this, not just you. We’ve seen those types of pictures before too. Perhaps the OP doesn’t realise how important the technical side of WC XC is, but that was not really the point.

The OP’s question was – perhaps a little naively – clearly more interested understanding relative merit of e-assist in a ‘fantasy’ WC XC race, over his own self-admitted meagre wattage output.

There is a tedious tendency on this forum to hit anyone on the chin immediately, if they lead with it. Rather than giving any potential naivety the benefit of the doubt by taking a more measured and rounded approach to forum replies.

Posting a series of hard-man pictures with the comment ‘may be an issue for you…’ just smacks of keyboard warrior wannabeism.

#rant #apologies – the bit you have about Jared Graves gives quite a nice insight to this.

..but the smugness of this place really does get my goat sometimes 😕

I believe there’s a somewhat unscientific video on GMBN that came to the conclusion that the extra weight and clumsyness of the ebike made it no faster than an XC race bike round an XC circuit.

Lets take a somewhat simplified example.
According to coggans power chart, an untrained (classified as a non racing cyclist) rider will have a the following P/W ratios:
2.5W/kg @ FT
3.0W/kg @ 5min
Lets assume a recreational cyclist is a little under the national average weight @ 78kg, giving FT and 5min powers of 195W and 234W respectively.
Adding 250W assist from the bike gives 445W and 484W.

Next we add 10kg weight penalty for the bike, and calculate using some pro level power outputs to find out what you would need to produce to keep up on the climbs.
6.0W/kg @ FT = 528W
7.2W/kg @ 5min = 633W

So the answer is no, not even close to keeping up. 83W short on FT power and 149W short on 5min power.

Mike… we all know how hard it is to ride an XC WC course. The guys are mentally skilled. We all know this, not just you. We’ve seen those types of pictures before too. Perhaps the OP doesn’t realise how important the technical side of WC XC is, but that was not really the point.

More a reaction to some of the usual comments that think XC is all about riding uphill these days, there was a chunk of stuff knocking the Rio course a while back some probably just a bit of boredom on my part… watching some of these guys come past you or trying to hang onto their lines is impressive!

Fair enough.. 🙂

fifeandy, good back of a fag packet analysis. Interesting to see where the tipping point is.

If you’re a decent club cyclist, say 70kg with a w/kg of 4.38 (~300W). Then an extra 250 watts and 10kg would give you about 6.88 w/kg which would probably win you the Tour, at least according to Dr. Ferrari…

Ferrari has calculated that anyone with aspirations of winning the Tour de France would be required to knock out 6.7w kg at lactate threshold.

Though as the durations shorten and the watts increase (typical XC efforts) those extra 250 watts become a smaller percentage of the overall output, so a WC rider may well have more more outright power at those efforts, and a much higher w/kg. And you have the weight penalty, which becomes more of a factor uphill too.

Say our decent club cyclist has a 1 MP of 8.57 (~600W) then the motor would give 10.6 w/kg. Probably a little short of world class.

..but the smugness of this place really does get my goat sometimes

The OP actually stated in his first response that he was very slow which could be fitness/technical ability or a bit of both (7.5mph average over 2 hours) so pointing out that the fact he is slow will be a drawback even on an eBike is hardly smugness is it?

And the question was: “Would I win a XC World Cup on an e-bike?”, for which the OP’s technical ability is very relevant, as an e-bike would be, at best, no advantage on the descents.

If the question the OP wanted to ask was “would I go faster than a world cup XC racer up hills on an e-bike” then it’s rather different.

If the question the OP wanted to ask was “would I go faster than a world cup XC racer up hills on an e-bike” then it’s rather different.

Even then it’s dubious. Assumption that the user cannot pedal aster than te max power assist of 25kmh. Lunchtime boredom internet browsing has the following:

The fastest speed on the la bresse WC climb is 15kmh by Maxime Marotte. Albstsadt is 21kmh by someone who’s name I don’t recognise as a top ten WC racer. Windham is 18kmh by Thomas Litschner.

So the, apart from La Bresse the speed isnt crazy different and its not te WC winner’s speeds. Then you have the factor that you have to be able to handle the heavy e-bike up the technical climb sections and not spin out.

So I am doubtfull if you’d beat a WC racer uphill on an ebike.

I just want to know which course it is with the ferns and big rocks?!

That was a nationals round at Rotorua, there is a great video of it with some of the locals more or less jumping down it

So I am doubtfull if you’d beat a WC racer uphill on an ebike.

The numbers seem to concur, especially as most XC climbs are relatively short (a few minutes max.)

Also there’s the factor of repeatability. Your capacity to repeat an effort close to your 1 minute max will likely be far lower than a WC racer. So maybe you might be close for a lap on those short hard efforts with the motor making up the shortfall, but then you’d be cooked as the pro’s go on to do half a dozen more laps.

WC racer Phil Pearce rides my local trails, I could see if I could borrow an eBike from my LBS and offer him a challenge 🙂

And with the utmost respect to Phil, he’s not troubling the leaders!

[video]https://youtu.be/AZnItiWFkoc[/video]

Here we can see Kulhavy spiking 900+W on a pretty regular basis at the Rio test event – our plucky ebike contender would have to be capable of producing regular 650-850W bursts unassisted (more when taking into account extra 10kg of bike) for the full 90 minute race duration.

On a side note – looking forward to watching the Rio XC race. Could be carnage at the back of the field as unknown riders from countries without a big XC racing culture hit some of those technical features.

😆

Aren’t e-bikes restricted to 15km/h? That would be a big problem…