freehub cassette vs. freewheel motor

adamf663 · Jul 24, 2015

I recently purchased 1) a motobecane 450ht as a donor bike and 2) the magicpie 4 conversion kit.

I'm now learning that the bike doesn't use a freewheel cassette, but uses a freehub.

Am I correct to assume that I can't use the cassette from the bike -- that only a freewheel cassette will work on the mp4 hub?
My plan now is to order an 8 speed freewheel cassette and mount that to the mp4 hub.

nutnspecial · Jul 24, 2015

Hiya!
I don't have specific experience with the kit or bike. I can offer what I know in general though.

Make sure you know the difference between freehub bodies that use cassettes and are held to the hub with a hollow bolt, and ,freewheels which screw to the hub with a large diameter thread (1.37). The two are not interchangable with off shelf parts.

Sram and shimano freehubs use (at least in my experience) a different hub/ mount, and also are not interchangable, although they generally do take the same cassettes.

There may be two different cassette remover sizes to watch out for. You should be able to count the teeth on the nut to order the right one. As far as removal of freehub from hub, both styles use allen wrenches from opposite sides of the hub.
If your conversion kit uses shimano freehub, then the sram's I've seen wont work- you'll need a shimano style, although the cassette should swap between both freehubs.

Hopefully that was helpful!

I recently purchased 1) a motorbecane 450ht as a donor bike and 2) the magicpie 4 conversion kit.

I'm now learning that the bike doesn't use a freewheel cassette, but uses an sram freehub. The shimano freehub tool I bought doesn't fit. The cassette is marked shimano. Is sram a different brand with different tooling?

In any case, once I get the cassette off, how do I move the freehub ratcheting mechanism to the hub motor? Impossible?

What solutions are there? Try to find an 8speed freewheel cassette?
Look for a freewheel->hub conversion -- a freeub that screws onto a freewheel hub? Do they exist?

adamf663 · Jul 24, 2015

I'm still learning.
The conversion kit's motor/hub has a thread for a freewheel cassette. Bike has an sram freehub.

My plan is to get an 8speed freewheel cassette to stick it on the motor/hub and leave the old cassette on the old wheel. Hopefully the spacing will be right for the shifter's indexing.

nutnspecial · Jul 24, 2015

Hey, we all are, right? You're plan is good, get a threaded freewheel with the gears ya want to screw onto the motor hub. There's no way to get shimano or sram cassettes to 'twine w/ a freewheel.

I bought the 11/34 freewheel and a removal tool, and they have worked great for that application.
http://www.amazon.com/gp/product/B00288JF4Y?psc=1&redirect=true&ref_=oh_aui_search_detailpage
http://www.amazon.com/gp/product/B001B6RGXG?psc=1&redirect=true&ref_=oh_aui_search_detailpage

motomech · Jul 24, 2015

This thread has gotten way too confusing.
First off;

I bought the 11/34 freewheel and a removal tool, and they have worked great for that application.
http://www.amazon.com/gp/product/B00288 ... detailpage
http://www.amazon.com/gp/product/B001B6 ... detailpage

This FREE WHEEL(leave the "cassette" off) has a 14 tooth small sprocket, pretty much useless for an Ebike application.
If the OP wants to pedal along at speeds in the high teens mph and up, he will need an 11 tooth sm. sprocket'
http://www.sheldonbrown.com/gears/
That is only available with the Epoch DNP FREE WHEEL;
http://www.amazon.com/DNP-Epoch-Freewheel-Nickel-Plated/dp/B007A8RS7I/ref=pd_sim_468_9?ie=UTF8&refRID=1M7ZBHVSHG3P5G040B89
Personaly, I don't care much for the 8-speed DNP, as there is a gap between the 3 rd. and 4 th. gears, that has caused me some shifting issues in the past and when I'm forced to use the DNP these days, I prefer the 7-speed(Even with a 8-speed system).
At the other end, the 42 tooth big chain ring on that donor bike is rather small, and it will take a 48T or 50T big chain ring to be able to pedal up to 25 mph.

teklektik · Jul 24, 2015

+1

Actually there are 3 varieties of the 7-speed DNP available (11-28, 11-30, 11-32) - all have the same lower 6 cogs - only cog 7 differs. I like the 11-28 -- the 11-32 has a huge gap between cogs 6 & 7 -- the 32 is a real granny gear that I don't need.

The tables show the ratio changes when I upped from 11-32 with 44/32/22 to 11-28 with 52/42/30.

nutnspecial · Jul 25, 2015

Yep, that's a 14/32 I linked- but it's cheap. The 11/34's are pretty rare and expensive now?
Op, just do the math for the speed you want to be able to pedal at. I currently run about a ~4 :1 high gear for a decent pedal cadence 25-30mph on a 24" wheel. 52/14 would be pretty close on a 26".

A good max cadence for max speed is 100-150rpm imo, and there are calculators to help relate that to wheel rpm for your wheelsize. From memory, on a 26", I think 400rpm is ~30mph and 500 rpm is ~40mph, so a 1:4 gear ratio is ok to shoot for. 100-150/400 or 100-150/500

dogman dan · Jul 25, 2015

Nothing like drinking from the firehose, on ES.

Your motor has a screw on freewheel. If you don't have one on the motor, buy a screw on freewheel.

Your bike will not care if it's freewheel or cassette. But it will matter how many gears. for 8 speed, just substitute a 7 speed freewheel. If you get an 8 speed, it will mean you have to spread the frame about 5mm. This is ok if your bike is steel. but if it's alloy just get a 7 speed freewheel. It will index good enough.

adamf663 · Jul 25, 2015

Thanks everyone for the help!
I had ordered an 8 speed DNP but just got notice that they didn't have it in stock.
So I'm getting a 7 speed Shimano MF-HG37 11-28 freewheel.
I have a 20ah battery and don't expect to do much pedaling so I don't care much about the top pedaling speed. I'd probably only pedal to get some exercise and to limp home if the battery runs out.

I'll be primarily using the throttle and no pedaling. I didn't order pedelec for it.

Just out of curiousity, how hard is it to upgrade the front top gear, to 48-52 teeth for example? Can a different ring be bolted on and then the front derailleur moved to accommodate the increased size? Probably not worth the effort for me.

nutnspecial · Jul 25, 2015

It's easy enough, I did it for the first time this year. Just search amazon/etc for "48t chainring" and note the different configs. There are generally 4 or 5bolt patterns for that largest position ring. And then look at 104mm, 110mm etc to confirm the right spacing. Other than that it's just getting the little hollow bolts loose.

That link to sheldonbrown.com really is a great go-to, I have learned alot on that site.

dogman dan · Jul 25, 2015

Bigger front ring can be easy or hard. It just depends on the type of crank you have, and if the frame has room for it. Often mountain bikes have no room for bigger than 48 teeth, before the gears rub the frame in the rear. Because of the fatter tires on mtb's. So it's not usually going to work to just buy a 52 tooth road bike crank, and try to put it on a mountain bike.

But it can be done. I have a 56 tooth crank that fits one of my mountain bike cranks. Some frames, usually older ones, it can fit.

I also converted a beach cruiser from a 44 tooth, to a 52 tooth, by using an old gear from a 40 year old Schwinn road bike.

motomech · Jul 25, 2015

adamf663 said:
Thanks everyone for the help!
I had ordered an 8 speed DNP but just got notice that they didn't have it in stock.
So I'm getting a 7 speed Shimano MF-HG37 11-28 freewheel.
I have a 20ah battery and don't expect to do much pedaling so I don't care much about the top pedaling speed. I'd probably only pedal to get some exercise and to limp home if the battery runs out.

I'll be primarily using the throttle and no pedaling. I didn't order pedelec for it.

Just out of curiousity, how hard is it to upgrade the front top gear, to 48-52 teeth for example? Can a different ring be bolted on and then the front derailleur moved to accommodate the increased size? Probably not worth the effort for me.

After all this explaining, you still ordered the wrong part :roll:

EPOCH DNP !!!!!
7 speed Shimano MF-HG37 11-28 is a cassette, not a freewheel!
Ebike Ca and Ebike SF sell them, just to name a couple of vendors for DNP's.

I have a 20ah battery and don't expect to do much pedaling so I don't care much about the top pedaling speed. I'd probably only pedal to get some exercise and to limp home if the battery runs out.

I'll be primarily using the throttle and no pedaling

.

No you won't. What you are building will have too much weight and drag to be able to pedal without power.
You will be able to run the system without pedaling though.
Don't want to sound too rude, but maybe you should hold off on ordering stuff and do some reading here for a while.
It could save you some money.

nutnspecial · Jul 25, 2015

It looks like the mf hg37 is a freewheel? Where are you getting that he bought a cassette for a freehub momomech?
http://www.amazon.com/Shimano-MF-HG37-Tourney-Freewheel-13-28T/dp/B001IORDH0/ref=sr_1_1?s=sporting-goods&ie=UTF8&qid=1437857904&sr=1-1&keywords=Shimano+MF-HG37&pebp=1437857891806&perid=0E1HPGZAE72J3NQVD2T3

DD makes a great point about checking clearances and crankstyle. My experience is limited to the 3pc mountainbike style cranks. Seems like the majority of the larger chainrings 48t and up are for 5bolt 110mm. (maybe these are considered road cranks, like Dogman mentions)
Mine is a 4 bolt 104, and 48t is the biggest I could find. Can't easily find it again right now, but it was about 15$, and there is no chainstay or deraileur issues with that or bigger.

motomech · Jul 25, 2015

Out of the dozens of Cassettes listed on Amazon, he found the one where the product is mis-labeled.
That is a cassette, look at the splines.

adamf663 · Jul 25, 2015

Fun never ends.
realized kickstand purchased will never support the added weight. heavy duty one for ebikes ordered.
freewheel cassette ordered
after installing new handlebars, learned that brake levers can't be R/R'd with them on. Left one was hammered on, will have to cut it away. will probably have to order a new throttle too to get a matching set
at least the battery fit, perfectly in the triangle

I knew it would be a learning experience.

nutnspecial · Jul 25, 2015

Hi momo, nah, those are just removal spline. There are threads in the back.

The confusing thing is hearing 'freewheel cassette', I'm pretty sure that's incorrect terminology, even though I see some parts listed that way. Hey, as long is it threads on, it'll work. But, I always thought cassettes were for freehubs, which don't thread to the hub, they use 10t cog styles different for shimano and sram.

Yeah adamf, I couldn't believe how much time I spent on controls, wiring, etc earlier this year. But it sure is nice to get it working well, just the way you want. FUN!

Even though it's been ascertained a freewheel was needed, and it was ordered- here is the differences between freewheels, freehubs, cassettes. A freewheel is the driver and gears. A freehub is the driver, with a 'cassette' of gears. These are for most bikes and 10mm axles. 12mm thru axles start to change things up a bit.
View attachment 4
cassette

shimano style freehub

sram style freehub

Freewheel

freewheel with it's gears off. Does not take 'cassettes'

adamf663 · Jul 25, 2015

learning terminology tool

Before I knew of freewheels and freehubs, I heard the stack of sprockets in the rear as the cassette. I've been calling the rear assembly "freewheel cassette" or "freehub cassette". I guess the correct terminology is "freewheel" or "cassette".

motomech · Jul 25, 2015

cancel the amazon orderone from these good folks.
http://www.ebikes.ca/shop/ebike-parts/freewheels/fw8spd1132.html

d8veh · Jul 26, 2015

The item listed on Amazon is a Shimano freewheel, but it doesn't have 11T top gear. The listing says 13T, but I count 14T in the picture. DNP and Sunrace are the only suppliers of 11T freewheels.

anoNY42 · Jul 26, 2015

I just want to set the record straight on the Shimano MF-HG-37. I bought one recently from a LBS, it's a freewheel with a 13T high gear. I believe there is a cheaper Shimano online that is a 14T high gear, that might be what's in the pic on Amazon.

adamf663 · Jul 26, 2015

a u r g h. Reviewed my order and it is a 13T for the high gear.
Oh well. At this point I don't care. I just want the bike assembled. I don't expect to do much pedaling anyway. That drivetrain, in my mind, is purely for limping home if the battery runs out.

nutnspecial · Jul 26, 2015

http://www.ebikes.ca/shop/ebike-parts/freewheels/fw7spd1132.html
http://www.amazon.com/SunRace-9-speed-11-32t-Freewheel/dp/B00ABHFZO8/ref=sr_1_5?ie=UTF8&qid=1437928764&sr=8-5&keywords=11t+freewheel

Rest assured you saved some cash for now at least. If upgrading to 48t or higher front (15$), and the near 4:1 ratio that would attain (13:48 or 13:52) is acceptable, it could be cheaper in the longrun anyway, although I think freewheels last for awhile, and they can even be serviced a bit (utube). 11t is just harder for them to pulloff due to the Id size/construction of the freewheels I guess.

Ps, yes, I just learned the hub/driver stuff this year adamf. Tricky the first time trying to get the right tools and parts when there are some unclear variations. Hopefully that helped!

Have fun!

dogman dan · Jul 27, 2015

yep. just get er going at this point. Later on you can refine your gearing, 11t in rear, and see what can fit in front.

FWIW, it's the older steel frame MTB's that were designed for a maximum width tire of 2" that can fit a 52 tooth crank.

Or, current model steel beach cruisers come with the cheezy forged steel cranks. For those, an old cheap ass 10 speed can supply a 52 tooth front ring, which fits fine.

On my current longtail, a beach cruiser I stretched. I took a chain ring off 40 year old Schwinn varsity 10 speed, and it fit perfect on the new Schwinn beach cruiser crank. No problem with the frame. As a bonus, I also now have a smaller front ring, I think its 44t. To shift to it, simply stop, put the chain on it, and I have lower gears if needed. Rarely needed, but there if I do need them.

adamf663 · Jul 28, 2015

I am we Todd did. I am sofa king we Todd did.

I got the shimano freewheel. When I tried to spin it on I promptly crossthreaded it.
I got it what I thought was on straight, but there was a lot of resistance. I had hoped that the resistance was from the correct threads forcing the freewheel past the crossthreaded threads.

Nope. Crossthreaded all the way. I wasn't even sure it was crossthreaded until I had it on the bike and fired up the motor. Then I saw the gears wobbling about 1/2 gear width.

Before I completely finish it off and destroy everything, can anybody give me any advice other than buy a new motor?

Is there a thread repair tool I can get to fix it? I'd need to know exactly what thread it has.

nutnspecial · Jul 28, 2015

Hey man! That doesn't sound like a huge wobble. It might be one of those times to just roll with it? Those things have a little wobble usually anyway, and if the chain and hub can still run properly, it will increase tightness as it's used.

There are very few tap/die that large, and they're really expensive ime, and that imo prob isn't gonna be needed anyway.

freehub cassette vs. freewheel motor

1 mW

10 MW

1 mW

10 MW

10 MW

100 MW

10 MW

1 PW

1 mW

10 MW

1 PW

10 MW

10 MW

10 MW

1 mW

10 MW

1 mW

10 MW

1 GW

10 W

1 mW

10 MW

1 PW

1 mW

10 MW

Similar threads