Question about building an etrike

Diddler

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Thinking of building a customer etrike. Have a couple concerns regarding etrike conversion kits. 1) don't care for how narrow the wheel base; desire a considerably wider rear wheel base, and 2) Also, don't desire a front wheel motor.

Thus, this question coming from a novice who simply doesn't know. Would a three wheel trike track ok if I placed an electric hub motor only on one of the rear wheels? I'll not be climbing inclines, nor would I be traveling sandy surfaces. Live in a retirement community in Florida, thus all riding would be on perfectly level, paved surfaces.

If your responses reflect an electric motor only on one side will generate good tracking (and not radically pull to one side), then this concept provides all kinds of benefits in my creative designing process in so far as making special fiberglass fenders, special seating, etc.

Thanks for sharing your thinking. As noted, never seen an etrike with a motor only on one side, thus simply don't know if such a concept would work.

Anxious to hear your wisdom. Thanks everyone.

Diddler
 
You may disagree - but a much simpler approach to electrifying a trike can be had when you spin the whole thing around to a tadpole design - this one is very upright and easy mount/dismount. You may be looking for a conventional one-wheel upfront thing to add cargo options?

https://hostelshoppe.com/products/r...PRT0Bxx_PPfuKMkcLzXH7SirDz4R_00xoCOWsQAvD_BwE

You could also drive the cranks with a mid drive motor rather than place a motor hub on only one side, which actually can work, if not well.
 
thanks for your ideas, but what about my original question. Would appreciate response to precisely my question. Thanks.
 
Yes, one rear wheel being driven by a motor is ok.... On many trikes only one wheel is driven by the chain to negate the need for a differential to allow wheels to turn at different speeds while turning.
 
It works, but it will push only from that side, so you just "get used" to steering a little bit off of straight to compensate.

The only real problem comes in turns in the direction of the side the driven wheel is on (true of pedals and of motors).

It cannot push you in that direction itself, so you steer "more" in that direction that otherwise, and tight turns don't work--the steering tire may just scrub / skid, and you may just get pushed into a straight line or even turn the wrong direction. ;) The wider the trike (especially for shorter ones), the "harder" the push in the wrong direction will be.

It's not too big a deal most of the time; my Delta Tripper trike only had motor power on one side, and my SB Cruiser trike only has pedal power on one side, and I managed in most cases to work around the issue while riding.

But there have been times I had to get off the trike and manually walk it thru a turn because the turn I needed to make was too sharp to overcome the push in the wrong direction.


When turning in the other direction from the side the motor is on, it will help you turn that way so it will be easier than expected.


The narrower the trike (the closer to the centerline the wheels are) the less of a problem it is. The longer the trike (for the same width) the less of a problem it can be.

(my SB Cruiser uses about the same width as the Delta Tripper, but it is a lot longer (and heavier); SBC has a bit less trouble with this than the DT, but since it is so much heavier I don't try to just pedal it around much and thus almost never deal with the problem since I have motors on both wheels).
 
Diddler said:
Thinking of building a customer etrike. Have a couple concerns regarding etrike conversion kits. 1) don't care for how narrow the wheel base; desire a considerably wider rear wheel base, and 2) Also, don't desire a front wheel motor.

A front wheel motor is infinitely better than driving only one of the rear wheels. It actually makes the trike more maneuverable because the steered wheel is pulling rather than being pushed.

Regardless, you don't want to go very fast at all on an upright trike because such a vehicle will turn over when steered at speed, and it has no stabilizing effect that increases with speed.
 
Chalo said:
Diddler said:
Thinking of building a customer etrike. Have a couple concerns regarding etrike conversion kits. 1) don't care for how narrow the wheel base; desire a considerably wider rear wheel base, and 2) Also, don't desire a front wheel motor.

A front wheel motor is infinitely better than driving only one of the rear wheels. It actually makes the trike more maneuverable because the steered wheel is pulling rather than being pushed.

Regardless, you don't want to go very fast at all on an upright trike because such a vehicle will turn over when steered at speed, and it has no stabilizing effect that increases with speed.

How stable do you think a Day6 trike with a 38” rear wheelbase might be?

https://cycleforfun.ca/product/day-6-joy-tricycle/
 
tomjasz said:
How stable do you think a Day6 trike with a 38” rear wheelbase might be?

https://cycleforfun.ca/product/day-6-joy-tricycle/

Well, that's a little wider than a typical granny trike, and the seat is a little lower for the same leg extension. So, it should be more stable than average on both counts. But not as stable as a true recumbent trike with a lower seat, or a pedicab trike with ~50" rear width.

At the point where the combined vector of gravitational force and centrifugal force intersects the ground outside the trike's track width, the trike falls over.
 
thanking everyone for your insights. At this point I'll pursue both front wheel motor and consider the option of a motor only on one rear side. But your comments provide worthying perspectives.
 
Chalo made the point that I have experienced:

"It actually makes the trike more maneuverable because the steered wheel is pulling rather than being pushed."

All the trikes I've built use FWD and in comparison to RWD the "pull" with FWD is a better feeling when riding. Not true for Harley Davidsons, Yammerhammers, Vincent Black Shadows and such. Tricycles around town are much better with FWD, also, weight of the rear is lighter for hauling stuff, or using a trailer.

https://www.youtube.com/watch?v=DmFm1sXKygI

Where will the battery be located? How about the controller? I like my controller to be up front in a bag or something - reduces the need to run wires on the frame.

Chalo, I think of trikes as pickup trucks, not "granny bikes."
 
TricycleMichael said:
Chalo, I think of trikes as pickup trucks, not "granny bikes."

In my world, "granny trike" is a format, not a purpose. Shorthand for upright delta trike, as opposed to semi- or fully recumbent delta trike or any kind of tadpole trike.

It's true that the upright delta "granny" trike format is better for hauling stuff than any other trike configuration, size for size. Paradoxically, its increased likelihood of tipover makes it less suitable for actual grannies than some other options.
 
TricycleMichael said:
Chalo,
My recumbent delta trike:

Zipster 3%22x150 dpi.jpg

Nice, this geezer likes it!
What is the base trike?
 
Thank you, my neighbor wanted to borrow my Tacoma to take stuff to the land fill which included the trike. The Worksman PAV was trash, left outside for 3 years, every bit was wasted. Rusted wheels, frozen bearings, no fenders, etc. Complete waste. I saw some potential, kept it and did a "jury rig" ride evaluation with a 26" wheel I had stashed to replace the 20" which required a new fork. Test ride was great so I went for it. New parts from Worksman and some ideas like a geared motor (DD would have been better for weight) 52v batt, dual torque arms (hot rodder at heart), poly fenders, painted in the driveway with rattle cans and blah blah. Strong wheels and this sucker corners like a race car, should have cut the seat down section 3 inches or so.
 

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I have an e trike, it did have a bafang front wheel, it's also got 4 inch fat wheels on it, I got the 1 I did rather than getting a tadpole design (which would be preferable from a handling/conversion point of view) but they are low to the ground and a bit risky if using on the roads and also your legs are horizontal which for me with a prosthetic leg isn't ideal.
The front wheel I found didn't feel much different to the mid drive I have now, so if this is an easy option for you I wouldn't worry about it being in the front,
I wouldn't suggest using a single rear wheel drive as it will pull to 1 side as it does if you only have 1 rear disc Brake functioning there is also a differential so if the bike you convert has this will be problematic for a single wheel drive too.
I, as you might have gathered had my front wheel stolen so decided to go mid drive, it was fought with problems but I got it done, the crank shell isn't standard width so I had to get 100mm bbshd and then had to clear out the middle of the shell with a hole saw as it was too narrow inside to get the shaft in, but the disadvantage is if your derailleur gets chewed up you are pushing your trike home, so there are advantages to having a front wheel hub motor, especially if you are disabled. If you buy it off the shelf it is also ready to ride though expensive for what it is but then that's trikes for you in general, the 1 I got was a Jorvik odin.
 
Another issue with rear hub motors, if your rear wheels attach like mine is they have a bolt through the centre, therefore the wheel hub is different to a standard hub, there may be solutions out there but it's something to consider as you won't be able to buy an off the shelf hub motor as they are like wheelchair wheels and no spindle through the middle, it all depends on the design of the trike you will be converting and your skill level at engineering, if the shaft is fixed with no differential then you could possibly put a freewheel sprocket on the shaft and use a motor and chain but again this will require some custom parts, and probably welding, the simplest solution if this is beyond your skill set or budget if you would pay someone then I would just go with a front hub motor, either that or a mid drive
 
eingWell, that's a little wider than a typical granny trike, and the seat is a little lower for the same leg extension. So, it should be more stable than average on both counts. But not as stable as a true recumbent trike with a lower seat, or a pedicab trike with ~50" rear width.

At the point where the combined vector of gravitational force and centrifugal force intersects the ground outside the trike's track width, the trike falls over.
Well I usually dislike necro threads but I thought my experiences with Day6 mifghtbe of interest. Firstly, no more trike for sale and parts support has pretty much disappointed me. Turns out the wide was shipped with a tweaked axel, and there are no replacements available. They did send me a new narrower complete axel but don't have the correct basket for it. The streering is pretty wonky and the first hundred miles is a bit scary until the rider adapts to the oddities. While Day6 sold the trikes with BBSxx series motors, the chain line is poorly adapted. A Delrin tube or similar on recumbents would be an improvement.

I'm about to add a MXUS 36V GD front motor out of fear of a chain failure, and being a gimp without a way home. Making the front GD a secure way home. I'll retire the BBSHD in favor of a BBS01B 500W 36V.

The bike is VERY comfortable. I ride every day all winter as long as the streets are clear. 2019 was impossible, but last year I rode nearly every day.

I can't help but wonder if a different front fork angle might improve the ride. But now that I've got 2 years riding the beast I'm golden. Hopefully the GD MXUS will give me some secure feeling. Getting stuck across town on a 20F day with a failed chain scares me. But then the middle 70's have a number of pitfalls. Real or perceived...
 
I can't help but wonder if a different front fork angle might improve the ride.
more likely changing the wheelbase would help more. the sb cruiser being long helps, as does keepign al the weight as low as possible.


if it's already a relaxed front end angle like my sb cruiser, it's probably good enough; too mcuh and you have really annoying flop. not enoguh and it gets all squirrely.

see my new schwinn-conversion thread for stuff as i work out converting an existing "unrideable" (at 20mph) design to something that will work as well as sbc.
and the drive dev thread for it
 
At about 18mph trikes get squirly, and either wheel can momentarily lift while turning, which may not be safe if you have the throttle engaged, causing a jump sideways? A consideration? Another caution is having a rear wheel that sits way out hitting a parked car, etc. As for using a front wheel hub, better have wide, solid, maybe shock forks for the motor to fit, and make sure frame is compatible with chosen fork.
 
more likely changing the wheelbase would help more.
Well I purchased a wider version and it really does corner very well up to 20MPH. However I discovered what was thought to be a fender rub, is indeed NOT. It has a bend in the last 6 inches of the wider axel. Not enough to create and other issues with ride and safety. Just frustrating. Day6 has no replacements but sent me the narrower version axel.

The steering geometry remains weird and disconcerting for anyone first riding the Day6 Wide Trike.

1737924813066.jpeg
 
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What is the axle? If it's just a solid rod, you can replace it with rod stock of the appropriate size (might have to drill hole(s) for cotter pins or whatever it uses to secure it all together). If the end is threaded (like this one) to hold a nut that keeps the wheel on (instead of a cotter pin) you might have to use a die to cut the threads into it, but you may also be able to just drill a hole for a cotter pin instead.
20250126_130457.jpg
 
Thinking of building a customer etrike. Have a couple concerns regarding etrike conversion kits. 1) don't care for how narrow the wheel base; desire a considerably wider rear wheel base, and 2) Also, don't desire a front wheel motor.

Thus, this question coming from a novice who simply doesn't know. Would a three wheel trike track ok if I placed an electric hub motor only on one of the rear wheels? I'll not be climbing inclines, nor would I be traveling sandy surfaces. Live in a retirement community in Florida, thus all riding would be on perfectly level, paved surfaces.

If your responses reflect an electric motor only on one side will generate good tracking (and not radically pull to one side), then this concept provides all kinds of benefits in my creative designing process in so far as making special fiberglass fenders, special seating, etc.

Thanks for sharing your thinking. As noted, never seen an etrike with a motor only on one side, thus simply don't know if such a concept would work.

Anxious to hear your wisdom. Thanks everyone.

Diddler

DONT!
Delta 3 wheelers were banned for very good reason: They kill people!

Find a 3 legged table and sit 'astride' one leg and do some imaginary swerving and leaning.
Get someone to simulate braking while swerving by 'lifting' on the opposite-to-lean rear leg of the table.
Basically you're heading over the bars and off to the opposite side of your 'swerve-brake'.
That's into the direction (car etc) you were swerving away from, with the 'rolled' trike on top of you..!

Also 80% of braking force comes from the front wheels in cars etc. (center of weight thing)
While one locked (Delta) front wheel wont kill you immediately like ABS on it would; you keep going in the direction you were headed just before it locked with NO steering! More grip = less locking for the same braking force and way shorter brake distances.

IF a (leaning preferably) Tadpole is trike (or quad), is out of the question;
here's the simplest, cheapest differential made from old angle grinders you can get:


"Too Weak! Those little gears wont last!"
Those 'little' Pinion 'gears' stand DEAD STILL relative to the side shafts.
ONLY when going around a corner do they very SLOWLY rotate...

The only time they spin like a top is when one wheel loses traction.
Like in a burnout 'but why's only one wheel burn outing!?'
Want a Limited Slip Diff that also does regen: Attach them to small, diff integrated, motor/generators...
 
Delta 3 wheelers were banned for very good reason: They kill people!
Banned where? Not where I am.

Have yet to find anything on the internet about a ban on bicycle delta trikes. If you can cite the specific law in the specific locality, it would be helpful.

I ride one for my work commute most of every week, in traffic. It's designed for this job, and does it well, and is safe to ride at the speeds (20mph or less) that its used at. More typical deltas are usable at only less than 10-15mph.



Also not aware of any of the bicycle delta trikes, as this thread in Bicycle Mechanical and Structural is about, killing people.


Sure, they have disadvantages. So do tadpoles. Depends on what you're doing with one, what your needs are, etc.

For the OP's stated usage, they could work perfectly (speeds and actual specific usage not stated, so can't say for certain, but the general retirement community usage suggests applicability).
 
Banned where? Not where I am.

Have yet to find anything on the internet about a ban on bicycle delta trikes. If you can cite the specific law in the specific locality, it would be helpful.

I ride one for my work commute most of every week, in traffic. It's designed for this job, and does it well, and is safe to ride at the speeds (20mph or less) that its used at. More typical deltas are usable at only less than 10-15mph.



Also not aware of any of the bicycle delta trikes, as this thread in Bicycle Mechanical and Structural is about, killing people.


Sure, they have disadvantages. So do tadpoles. Depends on what you're doing with one, what your needs are, etc.

For the OP's stated usage, they could work perfectly (speeds and actual specific usage not stated, so can't say for certain, but the general retirement community usage suggests applicability).

Those Gasoline trikes that are all quads now.

But yes; in slower moving stuff with the seat well back over the rear wheels, maybe... :)
Especially with a diff.

But 'not for me thx'.
 
Any trike configuration delta or tadpole, is hyper sensitive to proper weight balance.
Straying too far from 33% on each wheel is recipe for trouble.
Height of the "center of mass" plays into the dynamics as well, lower = better.
How many people do a balance check of their vehicles ?
A major flaw in the "banned" trikes is they had live drive axles (no differential)
To make a turn the operator needed to lift the inside tire thereby setting up the conditions for a roll over.
 
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