Tandem ebike?

[veloman]

I'm starting to think about it, for my gf and I to use to get around the city. The biggest problem we have when riding our pedal bikes is staying together. She is afraid to go more than 15mph or so, and hammers up hills so fast that I am not interested in pedaling that hard during commutes. Also, I feel it's dangerous to go <15 or 20mph on many streets. My own ebike is amazing because I barely get passed by cars and can mix very well with traffic.

I think if we try out a tandem and like it, I may do a conversion. I"d like to get out more on bike with her and I think that may be just the ticket. I told her it's impossible to go over the bars on a tandem. (that's one of her fears).

So I'm thinking of a 10 turn Mac set to about 1500w peak and 48v for ~26mph top speed. Nice fat CST 26 x 2.4" Cyclops tires. It will be like being on a scooter in comparison to how slow we are on pedal bikes. We weigh 310lbs together. (I thought about doing a scooter build, but that would require a lot more investment and we wouldn't be able to go on the trails or other bike only places.

I could also use the tandem on my own for when I want to carry large things or want the high torque. I would only need to invest a little bit more in battery at this point.

 

[Warren]

"I could also use the tandem on my own for when I want to carry large things or want the high torque."

Make sure you put a big load on that rear wheel. As a long time tandem rider, I can tell you that riding a tandem alone, without added weight on the rear, is deadly.

 

[rojitor]

I'd rather prefer two bikes at 15mph, but that's just my opinion.

 

[John in CR]

Forum member Fitek has done a couple of cool little compact tandem with the pilot in front and recumbent, though no pedals for the passenger. He never could get the handling right, uncontrolled weight high and to the rear.



On my project list is an ebike similar in layout that I've already named the school taxi rocket. I believe putting the passenger in the front comfy position and lengthening the wheelbase in back will fix the handling issues. I want to go even further and make the front a narrow bak fiets type aerodynamic box for the kiddies, adult passenger, or cargo with an inline bench seat to house lots of batteries. It might need a fold down or to the side front nose cone for easier access in and out, or maybe a fold over roll bar that doubles as kickstand and step.

It's still a moving target, but maybe you can take some parts and run with it. I can't imagine the stoker being a pleasant position, except maybe with girl in front, but I'll pass on not being in control of any 2 wheeler I'm aboard.

 

[Andes]

Veloman,

It sounds like my problem, and I did exactly that what you are thinking of.

Here is my tendem ebike, she pedals, if she want, but I deal with the traffic, I can tell you that the problem is solve!

 

[veloman]

Andes-
Awesome! It's good to see it's working out for some people. The biggest issue is that my gf is very non-aggressive when it comes to dealing with traffic, and has a very delayed response to my directions. I am going to get her on my low power ebike soon, but even then I doubt things will be much better, I hate worrying about her in traffic.

You might want to put a support on that rear rack - it's likely to break on a bump

 

[corkscrew]

When I listed my home built long tail cargo bike for sale, two gents pulled up on an old schwinn tandem bike, complete with a trailer and a child seat. Was powered by a stoke monkey.


So yes, I'd say it can be done.

 

[neptronix]

I've thought about something like this as well, to totally replace the car. My lady is in love with the Yuba Mundo, so she's warmed up to the idea of big heavy cargo bikes already. The problem is that our combined weight is about 450lb, then add another 38 pounds of battery because i want the range to be a non-issue.

I worry about the braking capability, frame strength, and wheel strength of the bicycle at that point.
Maybe a weight loss goal is in order. We are 6' and 5'10 though, so there may be a good 100lb. to disappear between the two of us. That's still 350lb tho, plus battery.. and we have hills to deal with..

When are they gonna come out with 250mm disc rotors for bicycles? :lol: