Folding Bikes - How confident are you in the strength of a folding bike?

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varaonaid
05-19-12, 01:58 AM
I'm working on an unusual project and a couple of people have agreed to help me...but I need some advice from those familiar with folding bikes.

I'm disabled and in the process of working on putting an electric motor on a bike. My husband and I had our first try on a 20" wheeled bike today (Dahon Speed series...important b/c of chromoly frame) and we fell in love! We live in a moderately hilly area and I have to pull a trailer with my service dog in it (70lb labradoodle) so it's going to be a more than averagely strong motor but not a monster. It just has to safely get us around.

So, would you feel comfortable with this rig on your (or a) foldable bike? The chromoly steel frame was suggested as it's more forgiving than aluminum but never having ridden a folding bike more than few minutes at a LBS, I have no idea what to expect or if they're up to the task. I hope they are because we really want to go that way...but I want to be safe. So I'd love to hear your thoughts.

Also, I have to go to Europe for some very specialized airway treatments that aren't available in the US or Canada. If we go with a folding bike, we'd like to be able to take them with us to Europe. Any problems that you've heard of transporting an electric bike on a plane?

Thanks in advance!!


ttakata73
05-19-12, 05:54 AM
My only concern with folding bikes is when I make sudden vertical changes like dropping off a curb.
I always fear the hinge will break since I'm 185lbs.

You seem to only be talking mostly about forces moving front/back so I wouldn't be concerned with the frame hinge on a Dahon Speed.
I would be highly concerned with that 2 piece stem which will be fighting all the weight of you, your trailer, and dog when you come to a sudden stop.
There will be hundreds of pounds of force trying to move forward as you brake.
If you just hit a curb face on at 10 mph, I bet that aluminum stem or joint would eventually fatigue and snap launching you forward.
I would try to avoid anything with hinges related to the stem so I would look into a rugged folding mountain bike or a mountain frame that has frame couplers.
I'm not a physicist but that's just my logic.
Do with it as you will and good luck in your travels.

donheff
05-19-12, 06:21 AM
I wouldn't trust my skills assembling such a thing but there are plenty on the market (http://www.nycewheels.com/electric-folding-bike.html). I would put more trust in the liability pressure on commercial firms to design a modicum of safety into the setup.


blakcloud
05-19-12, 06:54 AM
For most airlines you cannot take an electric bike because of the batteries. TSA regulations won't allow you to if you are flying out of the US. Do a Google search and you will see the restrictions.

HGR3inOK
05-19-12, 08:32 AM
For most airlines you cannot take an electric bike because of the batteries. TSA regulations won't allow you to if you are flying out of the US. Do a Google search and you will see the restrictions.
Maybe the batteries can be purchased at the destination and then sold before the return flight. The weight savings might result in a lower shipping cost for the bike.

-HANK RYAN-
Norman, Oklahoma USA

fietsbob
05-19-12, 09:30 AM
LBS out here sells Emoto,they have a folding electric bike, about a $k+.

but the weight of the motor and battery is significant..
keep the range capacity of the battery in mind.
does not sound like you are capable of carrying bike when battery won't move you.
electric assist is like a tailwind, but you have to pedal too.

flying will have over weight charges , for it. as a checked luggage item.

the Haz mat issue with the battery presents a problem

and there are not really universal methods of how the batteries mount
in the bike , so brand and model specificity need to be followed,
in ordering another battery,shipped separately, to meet you at your destination.

badmother
05-19-12, 09:56 AM
Is it possible for you to travel with something that is accepted as a personal mobility aid instead of this bike or rent something like that when you arrive in Europe?

For where you live: I agree about the folding stem getting a lot of stress but what about a minivelo instead of a foldingbike? You find plenty of posts here about minivelos.

HGR3inOK
05-19-12, 11:33 AM
... what about a minivelo instead of a foldingbike? ...
Is there a step-thru minivelo? I expect part of the OP's attraction to the Dahon Speed frame is its low step-over. :)

-HANK RYAN-
Norman, Oklahoma USA

badmother
05-19-12, 01:34 PM
Is there a step-thru minivelo? I expect part of the OP's attraction to the Dahon Speed frame is its low step-over. :)

-HANK RYAN-
Norman, Oklahoma USA

Depends how deep you need to go:

http://lovelybike.blogspot.com/2010/12/decide-2-ride-boogie-small-wheeled-non.html

http://lovelybike.blogspot.com/2012/05/small-wheel-shoppers-wren-and-bobbin.html

The first one should be ok. There is more out there for sure.

bbmike
05-19-12, 02:02 PM
In my opinion motorized bike should be equipped with disc or hub brakes-rim brakes are just too inconsistent. Otherwise, 20" folding frame will do as long as the motor is in the back (folding bikes with aluminum forks would be to weak plus pulling forces might be too much for the hinge
)

badmother
05-19-12, 02:19 PM
Some Alu folders have steel forks- like my white folder.

There is a forum for electric bikes and also one for special needs/disability. Did the OP look there.

And then: It comes to my mind a picture of a R20 with a front rack and on the rack mounted an engine, from grass chopper or something, not sure. Anybody remembering this and is it possible to find it? Not as a sugestion to the OP of course.

crackerdog
05-20-12, 09:35 AM
Do you need electric assist for the dog trailer or for the bike without the trailer? If you always have the trailer when you need assist, I would motorize the trailer and not the folding bike.

HGR3inOK
05-20-12, 10:20 AM
Depends how deep you need to go:

http://lovelybike.blogspot.com/2010/12/decide-2-ride-boogie-small-wheeled-non.html

http://lovelybike.blogspot.com/2012/05/small-wheel-shoppers-wren-and-bobbin.html

The first one should be ok. There is more out there for sure.
Interesting. Thanks for the links!

-HANK RYAN-
Norman, Oklahoma USA

fietsbob
05-20-12, 10:26 AM
Seen people put motor wheels in 2 wheel trailers..


but as far as topic header,I have a Brompton and a Bike Friday,
both good quality bikes.. could be set up with hub motors.

rodar y rodar
05-20-12, 04:15 PM
And then: It comes to my mind a picture of a R20 with a front rack and on the rack mounted an engine, from grass chopper or something, not sure. Anybody remembering this and is it possible to find it?
Maybe this?
http://www.outsideconnection.com/gallant/hpv/mred/

anthonygeo
05-20-12, 05:09 PM
Any of you over 200lbs? I've been wondering the same thing considering my weight.

bbmike
05-20-12, 08:12 PM
To put an electric motor in front one would need to, at the least, change to disc brake capable fork. Folding bike forks are not made for forces generated by the motor. In addition, motor in front will also add stretching/pulling forces on the frame which are likely beyond design spec of the hinge (not to mention some headsets). For those reasons motor in the back would be more optimal.

brakemeister
05-21-12, 01:53 PM
lots of electric bikes in europe
forget all the hassle and rent one over there...its going to be cheaper than the extra freight of the heavy bike ...not to mention the hassle to ship the battery seperately .... and hoping the 1000 dlr Ion Battery doesnt get lost anywhere in between...

thor

fietsbob
05-21-12, 03:06 PM
I'd make sure you have the documentation and Vet shots, up to date,
so the dog is not stuck in Quarantine.
UK , worried about Rabies, it was 6 months.. in the Heathrow Kennel..

varaonaid
05-24-12, 12:27 AM
Under 200 lbs. We opted to go with a similar bike but that doesn't fold. Has better battery storage options and is a bada$$ little chic mini velo. http://www.origin-8.com/?page_id=91&short_code=Bully&cl1=BICYCLES another link: http://www.bicycletimesmag.com/content/interbike-mini-review-origin-8-bully

We'll make some upgrades and change to a more swept back handlebar style. May put some Schwalbe tires on it, racks, upgraded V brakes etc. I'm pretty stoked. AND it's the preferable chromoly steel with perfect rear drop outs for the motor (although we're going to try both front and back for the motor given the much shorter wheelbase. :)

jur
05-24-12, 03:20 AM
... given the much shorter wheelbase. :)I checked the geometry chart and I see it actually has a normal to long wheelbase, over 100cm.

bendembroski
05-24-12, 04:31 AM
My only concern with folding bikes is when I make sudden vertical changes like dropping off a curb.
I always fear the hinge will break since I'm 185lbs.

You seem to only be talking mostly about forces moving front/back so I wouldn't be concerned with the frame hinge on a Dahon Speed.
I would be highly concerned with that 2 piece stem which will be fighting all the weight of you, your trailer, and dog when you come to a sudden stop.
There will be hundreds of pounds of force trying to move forward as you brake.
If you just hit a curb face on at 10 mph, I bet that aluminum stem or joint would eventually fatigue and snap launching you forward.
I would try to avoid anything with hinges related to the stem so I would look into a rugged folding mountain bike or a mountain frame that has frame couplers.
I'm not a physicist but that's just my logic.
Do with it as you will and good luck in your travels.

I know the OP has decided to go in a different direction so this isn't an issue for her, but I thought I'd reply in case someone else came across the thread.

When coming to a sudden stop, the only force on the stem will be the pressure from the weight of the rider (which is usually offset by pressing against the pedals when braking hard). The trailer and dog won't have any effect on the stem at all.

pacificcyclist
05-24-12, 11:28 AM
I'm working on an unusual project and a couple of people have agreed to help me...but I need some advice from those familiar with folding bikes.

I'm disabled and in the process of working on putting an electric motor on a bike. My husband and I had our first try on a 20" wheeled bike today (Dahon Speed series...important b/c of chromoly frame) and we fell in love! We live in a moderately hilly area and I have to pull a trailer with my service dog in it (70lb labradoodle) so it's going to be a more than averagely strong motor but not a monster. It just has to safely get us around.

So, would you feel comfortable with this rig on your (or a) foldable bike? The chromoly steel frame was suggested as it's more forgiving than aluminum but never having ridden a folding bike more than few minutes at a LBS, I have no idea what to expect or if they're up to the task. I hope they are because we really want to go that way...but I want to be safe. So I'd love to hear your thoughts.

Also, I have to go to Europe for some very specialized airway treatments that aren't available in the US or Canada. If we go with a folding bike, we'd like to be able to take them with us to Europe. Any problems that you've heard of transporting an electric bike on a plane?

Thanks in advance!!

At one point in time, I had a Bionx P250 installed on my Dahon Mu SL (which is an aluminum bike) and that was then considered one of the lightest electric bike. The bike was tough enough to handle pretty much anything with a motor up to 500W if you can afford the price tag. Certainly, you don't have to worry about durability but rather the durability and reliability of the electronics on electric components. This is due to the fact that if you travel in mostly rough roads, the constant vibration that does no harm to your frame can eventually loosen some components on the PC board or the computer connections. This was what happened to my Bionx system. It became so unreliable that I eventually sold it and really all the electric bikes nowadays will have issues with reliability as most systems are using you as test subjects and subsequent systems are improved to address those issues. So, my advice to you is if you are planning to electrify your folder is to stick with a good brand like eZee, Bionx etc. Because once the electric system failed on your folder, then it's basically a boat anchor. Also, changing flat on an electric motorized bike is a pain too as it is not quick released based, so unless you ride in places like Arizona where you'll more likely to get flats than say in Vancouver, then you need to balance the inconvenience with the convenience of having the electric bike.

A 250W motor is ok for mild grade hills towing a trailer -- I tried it once with a BOB trailer when I still own that.

If you are planning to travel to Europe, then you can't bring your batteries with you on a plane due to Hazmat regulations. Worst, because the motor looks like some kind of a bomb itself when x-rayed (winding coils and magnets), you might have an interesting time explaining that to a security officer and may delay you boarding the plane. It will surely be taken apart in the security office and inspected and because the motor itself is heavy, the officer might want to inspect it further to make sure the motor itself does not have embedded batteries in there since you won't include a battery with the bike in the case. If the officer suspects that it has a battery in the motor, the officer can legally seize your whole bike. Which means, you have to bring some documentation of the design of the motor which you will have a hard time getting it from the motor manufacturer! Not to mention that if you get through all this, you will then have to source out a battery in Europe plus the charger that works with the local outlet since Europe electrical standards differs from North America. After you used it, how much could you get your battery back for? Tricky cause no one will assume a used battery to be in any good condition anyhow since most reason people sell used batteries is that they are used and some cells are dying. So perhaps, a wise choice would be to just rent an electric bike in Europe and save all the hassle?

I was exploring this when I had my Bionx system, but once I realized the extra hassle and headaches that come with it, I just gave up. But it would be cool to unfold the bike out of the airport and just ride it like a motorbike!

badmother
05-24-12, 01:53 PM
Maybe this?
http://www.outsideconnection.com/gallant/hpv/mred/

YES!!:thumb:

MadCityCyclist
05-24-12, 06:18 PM
I'm 230 pounds with two folders, a Brompton M6L and a KHS F20-A. I've never worried about breaking them, they're both pretty solid. The only time my weight becomes a factor is when I have to re-tighten the seat clamp every once in a while, but that probably has more to do with the fact that the seat post is loosened every time the bike is folded in order to compact the frame.

I'm also into utility cycling big-time, and I have two trailers which have been attached to both bikes for 10-12 miles rides with lots of laundry on it, and I go on grocery runs several times a week (probably no more than 10 pounds in the bags) with no problems.

It should be noted I live in a city with lots of well-maintained bike paths (thank you Madison!), so the terrain is pretty smooth, and I don't ride my folding bikes as aggressively as my other bikes. But for average riding, they can pull a fair amount of weight.

For an electric folding bike, or any electric bike in general, you'd probably want the aluminum frame. The more weight the motor has to pull, the sooner it will drain the batteries.