Does a mid drive really need a freewheel?

[Retrorockit]

The weather cleared up and I got a 30 mile ride in with 1- 14# zip tie. Seems to work just fine. So I would start with just 1 and leave it at that if possible.
This doesn't solve my original problem of slop in the bearings of an 8 speed freewheel on a mag wheel project. But may be I can tighten it up to a point where its a slip fit and get the benefit of this mod that way.

[Retrorockit]

I had a user try this, and he dropped off a curb "like a child" in his own words, and had a chain drop. Pushing the chain forward probably makes it more likely. The single 14# zip tie broke and let the rear hub freewheel. I've been riding with just one and it seems to work just fine. So I would start with just one until you see how it works for you. My bike already has a roller chain guide to stop chain drops. Chain drop prevention may be needed for this.

[Retrorockit]

I'm still riding this setup and very happy with it.
!- A BBSHD when pedaling applies power at the level selected. So if you pedal to shift you are apllying power. if you stop pedaling then the power cuts. So it makes sense to shift then. The zip tie allows this.
2- Shift sensors have a fixed delay. Too long for rapid acceleration, and the power cuts back in when it's over. A problem during braking. I took mine off.
3- This can put slack into the upper run of the chain. Bumps, upshifts when coasting after throttling the BBSHD. A front top chain guide seems to work. I already had one. The Wide/Narrow solution is good for side to side chain issues, but not for slack in the top chain. Universal Cycles has a couple that go on the seat tube. Chain Spy , and Lil Chap are 2 of them.
4- The breakaway feature is important. One 14# zip tie is working for me. I haven't needed it but one other user did.
This is staying on my bike.

[Retrorockit]

Now that I have about a month in riding with this mod, I started another thread just about the zip tie mod itself. Basically this post here, is the start there.
This thread wandered around some and it started off as a question about a different project.

https://electricbike.com/forum/forum/main-forum/diy-discussion/156222-mid-drive-cassettte-zip-tie-mod

[Retrorockit]

I'm back at trying things out for the Mag wheel mid drive project. I want to use more than 1 zip tie to take the play out of the bearings in the 8 speed freewheel. I installed 3 small ones to stabilize it, but pulled them really tight so the static load was already high. Then tested the breakaway by turning the cassette backwards. Of course it was higher than 1 zip tie but seemed reasonable. So the breakaway force can be tuned by preloading the zip tie(s). Since I'm using the front freewheel mod the freewheel bearings don't really do anything now.

[Retrorockit]

I'm still riding w/o the rear freewheel active. I had to come up with a more effective chain management solution (recumbent parts) since the drive side of the chain goes into slack under some conditions. But I'm still using the Gripshift and multiple up and downshifts, pedaling or not. This is particularly nice for traffic circles, and fast left turns where the bike is leaned over and you can't pedal. Up and down shifts as needed just lifting the throttle to release the front freewheel.. I didn't have a lot of chain drops (a couple) but the zip tie kept breaking letting me know there was still an issue.
Here's the newer thread on this mod. I haven't broken a zip tie in a while. Or had a chain drop. Added bonus-full throttle in my cross chained lowest gears.

https://electricbike.com/forum/forum/main-forum/diy-discussion/156222-mid-drive-cassettte-zip-tie-mod

[Retrorockit]

I was at my local thrift shop that usually has a bike or 2 out front. So far the most interesting was a Stromer, and I picked up a couple folding donor bikes too. Well today there was a real unicorn there, and just about perfect for this thread. A brazed frame vintage Schwinn. Good old American made stuff. Now it starts getting weird. Drop bar 10 speed, but step through frame with 24" wheels.
I said it was "starting" to get weird. On closer examination it also had an FFS crankset, and Positron derailer. That's right I stumbled across a Shimano Front Freewheel Schwinn. I took a photo but IDK when it's going to show up in my email. With it's drop bars, and frame mounted shifter I'm sure it rode nothing like my MTB gripshift layout. No sign of special chain management. Just a 2 speed front derailer. Big chrome dork ring, and chainring protector too. Candy Apple red and chrome. Schwinn made some sharp looking bikes back then. Even the cheaper ones looked great. I'll get a photo up when I can. My LBS guy says nobody wants those. Are there any Schwinn collectors out there? I din't expect to bump this thread but here it is.

[73Eldo]

I think that era was the start of the 24" wheel bikes. Step through? Back then we called those ladies bikes or in the case of 24" wheels girls. Can't wait to see the pictures. The downtube shifter doesn't seem right for that era and level. The lower to mid range drop bar bikes usually had stem mounted shifters. Down tube came on the higher end. I would guess this had to be a Varsity or maybe Collegiate? I thought the Collegiate only came as a 5 speed tho....

[Retrorockit]

I took another look and it was stem mounted shifter and solid wire push/pull/.The steering was straight ahead so it looked like frame mounted at that angle.
Nothing form my cell phone has shown up in my emails.No update photos on the zip tie mod either.

[73Eldo]

Did you buy it? Or just take pictures and admire it a bit? If you bought it ya gonna throw a motor on it and ride it? Is 24 the new 26? I suppose very limited tire options in a 24 would be a problem.

[Retrorockit]

Schwinn FFS unicorn.

[73Eldo]

1979 Caliente $159.95. "Schwinn's own Elecro-fordged frame". Its supposed to have 'gumwall' tires and the odd plastic bar tape Schwinn used is missing. Oddly that seat position (front to back) is just about how its shown in the catalog.

[Retrorockit]

God help me! That bike is too small for me, wrong gender and I still want to fix it. I found some Sun Ringle Envy 24" red anodized rims, and some NOS Sturmey Archer drum brake hubs.90mm/f 70mm/r. Chrome riser bars with an 8 speed Rapid Rise Revoshifter ( I have a few of these). You can fake the FFS cassette with some plastic packing between the cassrtte and the chrome dork ring (gotta keep that!).

[11111energy]

Yes, a mid drive motor does need a freewheel. The freewheel allows the motor to disengage from the pedals and coast while the bike is moving forward. Without a freewheel, the pedals would constantly turn when the bike is in motion, even if the rider isn't pedaling. This would make it difficult to control the bike and could lead to safety issues.

Additionally, the freewheel allows the rider to coast without pedaling, which can be helpful for conserving energy or taking a break during a long ride. The one-way clutch in the cranks and motor are not designed to replace the freewheel and are intended to provide a smoother riding experience and prevent the motor from damaging the chain or other components.

Welding the freewheel to the hub or removing it entirely could cause serious damage to the motor and other components of the bike. It's important to use the appropriate freewheel for your bike and motor to ensure safe and reliable operation.

[Retrorockit]

I guess I could have stated it more clearly. "Does a mid drive (which has 2 freewheels inside of it) really still need the bicycle freewheel at the rear hub". That would make kind of a long title for the thread. I started another thread on this specific mod. That was about 6 months ago.
https://http://stateofthenation.co/?...te-zip-tie-mod
I've been riding with a locked out freewheeel since September. So this thread was the question. That thread is the actual answer.

[Retrorockit]

If you're pedaling that stuff is all in motion anyway. How efficient is pedaling when you don't need to?
The rear freewheel is noisy, My bike is much quieter without that racket.
1- I can shift when leaned over in turns. (Traffic circles with real traffic)
2- I can shift w/o pedaling when braking (which is kind of stupid)
3- I can shift when standing on the cranks for better visibilty, or bump absorbtion.
4- I'm much safer being in the right gear at the right time.
I've actually ridden bikes set up both ways.

[Circuitsmith]

Keeping the chain, derailleur, chain ring, and 2 freewheels in the mid-drive in constant motion adds drag and noise.
Keeping the chain in motion also adds an element of danger, reduced but not eliminated by a torque limiting zip tie.
Having to shift only while pedaling (or throttling) seems to me, much less of a nuisance than all the above.
Not such a burden, given a little anticipation, and a relaxed and deliberate riding style.

[AZguy]

Personally I don't think it's a big deal either way... I tried this and I get it that for retro this brings more to the table than it did for me... the greatest value I got from it was for stealth if not pedaling since the motor freewheel is far quieter than the hub freewheel... thing is that while I put a really high value on the stealth I mostly always pedal so that advantage is only seldom present... I just figure that if the zip tie broke (I just use one tiny one) I wouldn't bother putting it back unless for some reason a I anticipated the stealth need... after about a thousand miles my anecdotal experience is that it's given me no issues whatsoever and I don't have chain guides, etc., just a good derailleur system on a very wide range cassette (11-51t)

YMMV

[Retrorockit]

I think for the first time I could give my bike to an inexperienced rider, and as long as the PAS stayed at a reasonable level they could ride it with no issues. Up or down shift any number of gears at any time is a big difference. Of course if you have trigger shifters rationing the gears for you that benefit won't show up. Now that I'm waiting for parts for the motor I do find it tricky riding my XC bike to get back in the habit of pedaling even with a gripshift and Rapid Rise getting me 1/2 way there. But this is urban street rat stuff, and offroad, and open road riders can probably do without it.
I'm riding an obstacle course. But the obstaclea re all moving. Most of them are bigger and faster than I am.Except for the ones that aren't. It's a very undisciplined discipline.

[Retrorockit]

I suppose I should make a clarification about this thread. It's about getting rid of the rear one way clutch, whether it's a freewheel or a freehub/cassette.
Since I started another thread on doing that mod I'll go on a about freewheels vs cassettes here anyway.
Freehweels are an older format based on multiple gears on a single cog freewheel thread. The wheel bearing kind of stayed on the narrow single speed width, and the large outer bearing in th older freewheels meant they had 13t for the small cog. Fixed gear bikes use the thread also which work so m some IGH & hubmotors that have internal clutches. It's a staple in BMX also.
The threaded freewheel has lived on in hub motors and IGH bikes because the threaded mounting is convenient there.
Lately there have been threaded freewheels with 8-9-10 speeds and down to 11t cogs.

https://www.sunrace.com/category/products?product_group=freewheel

DNP Epoch is another brand popular with BMX guys.

https://em3ev.com/shop/dnp-11t-freewheel/

They say for mid drives, but many places that means 350W bikes So IDK what the deal is at over 1kW.
I'm also not seeing wider ranges than 11-34t. if you have a bike that needs that format it's nice to have newer options.
This eliminates the large bearing inside the outer cog, and does nothing about the narrow wheel bearing setup.
I'm guessing it works for pedal bikes, and maybe hubmotors. I will probably try it on a mag wheel mid drive at some point and see what happens just because the mags have that configuration.