Carbon Fibre Road Bicycle /w Oxydrive

I am on the verge of selling my CF Road Bicycle, but if I could convert to an ebike I think I might keep it.

 

Spec here

Planet-X Nanolight SRAM Red Large Road Bicycle - Dura Ace Wheelset | eBay

 

After 3-4 hours research last night I narrowed myself down to the Oxydrive, I like the style and I believe the performance will satisfy my needs.

 

I contacted the manufacturer of Oxydrive who said

 

Your bike has a carbon frame so this brings the risk of frame being damaged. The kit (battery unit with holder) is around 3kg and carbon frames are likely to crack where the decals are.

 

I've also emailed Planet-X to see if they think the frame can support a 3kg battery on the bottle mount.

 

Is anyone else able to offer advice in my endeavours?

 

Thanks

I think that you'd be better off selling it and get a more suitable bike for conversion. There's additional risk from the carbon forks not being strong enough.

I think that you'd be better off selling it and get a more suitable bike for conversion. There's additional risk from the carbon forks not being strong enough.

 

Thanks, though having paid £2000+ for the CF Bicycle - it feels a shame to take a loss in selling it only to buy an 'inferior' bike, albeit one more suitable to the task. Converting my current bicycle seemed like a nice way to keep it.

 

However if as you say, I cannot use my bicycle, then I may have to reconsider my options.

I agree with d8veh. It's not really worth the risk of face planting the tarmac, and possibly ending up underneath a car.

It's always best to over engineer when it comes to diy e-bikes

I know what you mean, but you need to be pragmatic. For the cost of conversion, you can buy a ready-made electric bike and keep your Planet-X. It's not so important to have a light-weight high quality bike when you have a motor to do most of the work. I enjoy riding the cheap ones just as much as the expensive ones.

it feels a shame to take a loss in selling it only to buy an 'inferior' bike, albeit one more suitable to the task.

You've pretty much said it here... The CF bike would be the inferior ebike due to being a death trap. The more suitable bike would therefore make the superior ebike.

 

The high cost of CF doesn't make it superior in this context.

Hi Dan,

 

If you really want a carbon fibre electric bike maybe this would suit you Cytronex 'Gadget Show' Cannondale Super Six Ultegra Electric Bike

 

Of course it doesn't help with the bike you have already and Cytronex don't seem to have a conversion kit available.

 

I certainly would not recommend one of our eZee kits for a bike with a carbon frame or forks.

I certainly would recommend one of our eZee kits for a bike with a carbon frame or forks.

Just to be clear... Is this a typo or do you really mean it?

I see the ROSE Bosch Xeon EL-2 has carbon forks. If it's OK for Rose is should be alright, depending on the quality of the forks of course. See ROSE Bosch Xeon EL-2 Men at a low price in the online bike shop www.rosebikes.com

Just to be clear... Is this a typo or do you really mean it?

 

Sorry, typo corrected:o

You've pretty much said it here... The CF bike would be the inferior ebike due to being a death trap. The more suitable bike would therefore make the superior ebike.

 

The high cost of CF doesn't make it superior in this context.

 

 

Hardly a death trap.

 

I've been running with Tongxin and then Cute 100 motor with peaks of 700watts for nearly two years on a carbon forked Trek FX. If you're not running high power and pay attention to the fitting I don't see an issue*.

 

*FYI carbon forks are stronger than alloy and steel forks. It's the failure mode that's a concern for some.

CF may be stronger but when it fails, it breaks rather than bends.

 

I have seen alloy forks break at the joint though... but under extreme force.

 

Personally, I wouldn't even trust carbon forks or wheels on an unpowered bike.

CF may be stronger but when it fails, it breaks rather than bends.

 

I have seen alloy forks break at the joint though... but under extreme force.

 

Personally, I wouldn't even trust carbon forks or wheels on an unpowered bike.

 

I've no problem with well engineered carbon, nearly everything in my motorsport dealings is carbon fibre - I even have a carbon fibre prop shaft on my Westfield.

 

http://www.youtube.com/watch?v=xreZdUBqpJs

 

So 40% more force to crack the carbon frame vs bending an aluminium one. You can see the different failure modes quiet clearly in the video. If I had a choice between a frame bending or one taking up to 40% more force before cracking - I'll take the 40% stronger one please. :-)

 

And if you though carbon was fragile - keep watching at the end where they smash it into a concrete block :-)

 

IMHO - carbon fork weakness is a myth. I seem to remember everyone saying (yes I'm that old) alloy forks were dangerous when they first came out and when steel was the norm ;-)

Edited May 15, 201312 yr by amigafan2003

I've no problem with well engineered carbon, nearly everything in my motorsport dealings is carbon fibre - I even have a carbon fibre prop shaft on my Westfield.

 

Pinkbike Visits The Santa Cruz Test Lab Video - YouTube

 

So 40% more force to crack the carbon frame vs bending an aluminium one. You can see the different failure modes quiet clearly in the video. If I had a choice between a frame bending or one taking up to 40% more force before cracking - I'll take the 40% stronger one please. :-)

 

And if you though carbon was fragile - keep watching at the end where they smash it into a concrete block :-)

 

IMHO - carbon fork weakness is a myth. I seem to remember everyone saying (yes I'm that old) alloy forks were dangerous when they first came out and when steel was the norm ;-)

 

So... can i:)

Having bent many steel forks in my time (never really got to grips with the spoons)...

So 40% more force to crack the carbon frame vs bending an aluminium one.

...this doesn't make me feel any more confident that carbon forks wouldn't oneday disappear beneath me.

Decent bike - nice components ...

 

I think you can fit an Oxydrive onto a bike with carbon forks - as long as you engineer it properly. If you're not confident specifying, installing and if appropriate making to measure an appropriate anti-rotation system, spreading forces adequately and getting tightening torques etc. correct then another route would be a far easier option.

 

As far as the battery is concerned I think it was Kudos (may be wrong) had batteries popping off the frame when using bottle mount screws on a carbon bike. So it isn't the easiest to work with. BH have integrated their battery into the frame design on their carbon bike, avoiding this problem.

 

Guess another question is - if you had to drill the carbon frame or add further bracketing (which would no doubt scratch / damage the frame) to reinforce your battery mount would you be happy to do that ? It might make selling the bike on as a carbon bike a bit harder - unless it was sold as a conversion - as I think people would shy away from buying a regular carbon bike that had been modified like that. A one-way ticket, if you like. I drew the line at drilling even my Trek Ally frame, or doing any dremeling of dropouts. With moulded in washers and the like it would have looked awful if the mounting design was ever changed and holes exposed again. Modifying dropouts on a front fork if you have to isn't such a big deal as you can replace them (bit more expensive with a frame !) but still they're expensive things to mess about with.

 

In a way, the bike looks a bit too nice as it is to turn into an eBike. I still have pangs of guilt when I look at the mods I made to the Trek. A bit like selling a horse into farm work once its racing days are over :o. Maybe selling it on as a trainer to someone who'd use it as it is would be kinder ?

 

I see the ROSE Bosch Xeon EL-2 has carbon forks. If it's OK for Rose is should be alright, depending on the quality of the forks of course. See ROSE Bosch Xeon EL-2 Men at a low price in the online bike shop www.rosebikes.com

 

That Rose bike with carbon forks has a crank drive motor so carbon forks aren't going to be an issue. I think the point is the Oxydrive is a front hub motor so issue of fork strength comes into play on account of that.

It's true, I don't want to be drilling into anything. I had hoped the oxydrive would be a polished package then required less 'diy' than most. wishful thinking maybe?

 

I did just weigh my bike in at 16lbs

It's true, I don't want to be drilling into anything. I had hoped the oxydrive would be a polished package then required less 'diy' than most. wishful thinking maybe?

 

I did just weigh my bike in at 16lbs

 

On most bikes it most likely is. But when slightly oval pegs and round holes come together you can't be sure just how much sanding you need to do till you start trying... .

That Rose bike with carbon forks has a crank drive motor so carbon forks aren't going to be an issue. I think the point is the Oxydrive is a front hub motor so issue of fork strength comes into play on account of that.

 

I never thought of that, thanks, I have learnt a bit more.

...this doesn't make me feel any more confident that carbon forks wouldn't oneday disappear beneath me.

 

If you can put enough force through a set of carbon forks to crack them, snapped forks will be the least of your worries!

 

Carbon/composite failures you see are normally a result of manufacturing defects or faulty installation. Stick with well regarded manufacturers and fit them properly and no one has anything to fear from carbon/composite forks or frames.

I think if I was going to fit a kit to this bike I would use a frog battery that goes on to the rear of the seatpost (changing the seatpost for an aluminium one if it was carbon)

Decent bike - nice components ...

 

I think you can fit an Oxydrive onto a bike with carbon forks - as long as you engineer it properly. If you're not confident specifying, installing and if appropriate making to measure an appropriate anti-rotation system, spreading forces adequately and getting tightening torques etc. correct then another route would be a far easier option.

 

As far as the battery is concerned I think it was Kudos (may be wrong) had batteries popping off the frame when using bottle mount screws on a carbon bike. So it isn't the easiest to work with. BH have integrated their battery into the frame design on their carbon bike, avoiding this problem.

 

Guess another question is - if you had to drill the carbon frame or add further bracketing (which would no doubt scratch / damage the frame) to reinforce your battery mount would you be happy to do that ? It might make selling the bike on as a carbon bike a bit harder - unless it was sold as a conversion - as I think people would shy away from buying a regular carbon bike that had been modified like that. A one-way ticket, if you like. I drew the line at drilling even my Trek Ally frame, or doing any dremeling of dropouts. With moulded in washers and the like it would have looked awful if the mounting design was ever changed and holes exposed again. Modifying dropouts on a front fork if you have to isn't such a big deal as you can replace them (bit more expensive with a frame !) but still they're expensive things to mess about with.

 

In a way, the bike looks a bit too nice as it is to turn into an eBike. I still have pangs of guilt when I look at the mods I made to the Trek. A bit like selling a horse into farm work once its racing days are over :o. Maybe selling it on as a trainer to someone who'd use it as it is would be kinder ?

 

 

 

That Rose bike with carbon forks has a crank drive motor so carbon forks aren't going to be an issue. I think the point is the Oxydrive is a front hub motor so issue of fork strength comes into play on account of that.

 

Yes it was us who had the batteries pulling out of the downtube-the manufacturer had not appreciated the high loads on the battery mounts when the bike is subject to off road usage.

After the event I did question the validity of a carbon frame on an ebike.

With a sports bike if you can save 1.0kg off a bike weighing say 8kgs,the percentage saving is very high and if racing very critical but with the weight of the battery,motor and electrics on a 22 kg ebike the resultant percetage saving seems hardly worth the cost. Also the ally frames are getting lighter.

From my yacht racing days with carbon masts I do remember us constantly tightening fittings that had come loose with compression of the carbon fibre-similarly ebikes have a need for a lot of extra fittings not present on a sports bike and its the transition between carbon and steel or ally which seems to cause the problems.

I am not saying that a carbon ebike is not possible but I think it needs to be a ground up design considering the interaction of the fittings in the design of the frame,I doubt whether a bolt on kit would ever work successfully.

My advice,keep your lovely carbon sports bike intact and buy a sporty ebike,there some nice machines around now that keep the sports riding style with assistance.

KudosDave

Another point is a converted carbon frame ebike would be worthless - neither roadies nor ebikers would want to buy it.

Another point is a converted carbon frame ebike would be worthless - neither roadies nor ebikers would want to buy it.

 

It's only worthless if you want to sell it.

 

If you intend to keep it or ride it into the ground it doesn't matter if it's worth £2k or 1p.

 

And I'm not sure ebikers wouldn't want it - I've sold two bikes I've converted that had carbon forks. Never tired one with an actual carbon frame though.

If stressing the frames is a worry try a crank drive and a triangle frame bag for the batteries, the BB should have no issue with a 3-4 kg drive and a frame bag will spread the load with no high stress points on the frame.