E-Assist kit for conversion of LWB Recumbent

[Luscombe]

Noob here,
Hi, I am wondering if anyone on this board has put an E-Kit on a long wheel base recumbent. I have a Rans Stratus XP Aluminum and a Tour Easy and would like to install a kit on one of them. Looking for those who have done this and what they used.

The goal is to add an E kit to my wifes recumbent; Ran Stratus (26" wheels ). I admit that I do not know much about the technology but am a quick study and handy with tools. Not looking to create a hot rod, just a reliable assist. We live in southern Wisconsin, lots of trails and good riding but some hills. My wife is retired and likes to ride but does not have a lot of stamina. Seems like the E-Assist is a no brainer for this application. Problem is, I do not know what I don't know.

My thoughts are I should look at a Mid system on the crank that mounts to the bottom bracket or a rear geared hub system. I have ruled out front wheel drive and am leaning towards the Mid Drive system as it would not add any torque stress to the drop outs and aluminum frame components. The bottom bracket mount would add the least amount of additional stress.

Would like the system to have adjustable inputs for assist.

Any ideas, suggestions, advice, etc would be appreciated. Target budget all in is $1,000-$1,200. I want to do the work myself as it is a retrofit to an existing frame. I do not want to modify the frame with additional welding etc. FWIW, the Rans Stratus has Avid Disc brakes.


Thanks in advance.

Gary

 

[wesnewell]

To get started, see need advice in sigline. Then read this.
https://endless-sphere.com/forums/viewtopic.php?f=4&t=72975

 

[Warren]

Gary,

I grew up in Wisconsin. It is flat. Even the Kettle Moraine area is very short climbs. Why aren't you considering a geared front hub?

 

[Luscombe]

Plenty of hills in Blue Mound area.
Aluminum forks
Would like to be sure stable for my Wife to ride. Lots of caster on front wheel and concerned about slipping while cornering. That is why I am asking if any have done this E Assist to recumbent.

 

[amberwolf]

Have you seen my CrazyBike2 and SB Cruiser builds? (linked in my signature)

The former is an LWB semi-bent bike, heavy cargo hauler, 2WD. It's also been FWD, and RWD, and it does ride better as RWD vs FWD, though it's best as 2WD.


SB Cruiser is an LWB semi-bent delta trike, heavy cargo hauler, 2WD now (RWD), but has been just FWD; due less to weight distribution and more to wheel size, it also works better as RWD even with just one wheel driving.

With both of them, if I had smaller front wheels for the same motors, or higher power on the existing ones, the performance would be about the same with FWD vs RWD.


As for cornering vs FWD, that's something you just have to practice at letting off throttle when you're turning, then reapplying power as you get out of the turn, when on surfaces where traction could be lost because of it. (continuing the turn on leg-power instead). Or simply slowing down enough to not worry about it.


There are also several SWB/MWB 'bent builds, using the Bike-E.

Dunno if Dogman has ever motorized the LWB 'bent that he and I used as a design base for SB Cruiser's front frame, but I suspect he'd've used a rear DD hub on it if so, because of the tiny (16"?) front wheel.

If you search on "recumbent" or "*bent" and list by topic, you'll probably find at least a few threads about builds that can help you decide.

 

[ebent]

For quality and reliability with excellent advice and customer support contact Grin technology. http://www.ebikes.ca I used them on my second build on a HP Scorpion FS 26. Most on this website will agree that they are a preferred provider.

 

[dogman dan]

Any decent rear motor kit will be fine for your bent. I'm not sure if there are any quirks that would make using a mid drive kit awkward on your bent. Stressing the frame is no problem, if you use a torque arm on the motor. The best rear torque arm comes from Grin.

They are also pretty easy to make yourself with simple tools, if you have a drill, small file, and maybe a 4" grinder or bench grinder.

FWIW, I did put a rear E-bikekit motor on that bent of mine. 20" rear wheel, and since the frame is steel I added bob trailer mounts to it.

 

[Warren]

Luscombe,

"Plenty of hills in Blue Mound area."

Yes, but short enough that a hub motor isn't going to overheat, if run at WOT.

"Aluminum forks"

Yeah. That would be a show stopper for me too.

"Lots of caster on front wheel"

A floppy front end shouldn't be exacerbated by weight added at the wheel center.

"concerned about slipping while cornering."

Yup. But you need to pay attention to the front end on a LWB in iffy conditions anyway. If you take it easy, the added weight should actually help. And with a powered bike, the drag of adding a big fat front tire wouldn't be problem.

Everything in life, and engineering, is a compromise, Warren

 

[Jonathan in Hiram]

I have a LWB bent with an ebay 9 Continents clone direct drive on the 26" rear, works fine for me at 12s and as you can see from the pic we don't really do flat around here. The biggest single trick to riding a DD hub on my type of rolling terrain is pedal hard up the hills and relax the rest of the time, you'll probably spin out your legs on the level anyway and downhill you might as well forget about pedaling. I have a fairly large and heavy battery in the box, the extra weight on the front 20" Schwalbe Big Apple really helps it feel more planted and stable at speed than without the electric system.

 

[Luscombe]

Thanks to all of you that posted a response and for the PM's. I am leaning towards a Mid-drive set up. I think that it will be the easiest for my wife to manage. It seems that a 500W PAS system will give her the assist while allowing her to ride like a normal bike.

I will continue to read and study the options. I plan on getting started on a kit sometime after the first of the year.

Thanks

 

[dogman dan]

Nothing wrong with the mid drive idea. You will be seeing less and less of hub motors in ready to ride bikes real soon. The current generation of mid drives is not like the ones from 2005.

It's just that depending on how your frame is, it may or may not fit like it's designed to. It will likely be designed to go on a regular bike frame. So you may have some small issues to resolve depending on how your frame is actually made. Nothing should be a deal breaker, but it might not bolt on right out of the box. Or maybe it will. I just don't know. If your bike is just like Jonathans, a bafang kit might bolt right on easy. That looks almost like a normal bike at the crank.

A rear hub though, that should be an easy and straightforward install. PAS or not, you can have either with a hub. Many of us just did a rear hub motor because it's easy, accessible, and cheap. You would definitely not want a front hub motor on a LWB bent.

 

[Warren]

Luscombe,

Sorry. Not enough coffee yet. Check your thread on BROL.

 

[ColinB]

I've enjoyed my Sun EZ-1 so far. Having some hills here also, I would not want to lose my triple chain ring at the front. I use all my gears.

Easiest solution would be a Bionx system. They ride very nicely. Ebikes.ca is great - used them myself.

Colin