first trip

i cannot keep the original 21 speed cause i am adding a hub motor and it need a bit more space so i have to use a 6 gear. from what you say i will not be able to use my original 21 speed shifter with the new 6 speed(18) exact?

first trip

hi ill have to see if i can find a 5 speed megarange. do you know if i can buy a megarange 5 speed freewheel? so far i cannot find one.

Also you suggest friction shifter for 5 speed, why ? friction is less fun to use than indexed

tx

JohnDThompson 

"Megarange" is Shimano marketing-speak for a freewheel with several relatively closely spaced sprockets for the higher gears and a large jump to an extra-low bail-out gear. I'm not aware that they were offered with anything less than seven sprockets. That said, SunTour and Shimano both offered five-sprocket freewheels with 32 or 34 tooth large sprockets. These should be available on the used market. Modern production five-sprocket freewheels seem to top out at 28T.

There are precious few indexed shifting systems available for 5-speed, mostly pretty low-end, and the freewheels that work with them don't seem to offer sprockets larger than 28T.

first trip

does that also apply to 5 speed megarange ( that it would be ok as long as it is not higher Rder than no 9)

first trip

HI so if i read you well if i go down to 5 speed i will probably have to forget index is that what you say to me , it is important. tx

Bigbus

I dare you to say that over in the C&V subforum haha

Bill Kapaun

The knowledgeable people in CLASSIC & VINTAGE know it's pretty much obsolete.
That's why they have their own forum for such.
Old doesn't mean non serviceable.
They also know the pitfalls.

Bigbus

I am not aware of any 5 spd indexed shifter. Many 6 spd for cheap. Maybe you can set the limiter screw and not use one of the cogs (either high or low-your choice) and then you'll still have indexed. Unless the pull ratio (cog spacing) on the 5 spd is different than on a 6 spd. Cycocommute would know that answer. Why don't we ask him if my suggestion is plausible because that might be your best option.

cyccommute 

Yes but you probably won’t find a 5 speed indexed system. There were some very early...and very heavy as well as poor operating...attempts at 5 speed index.

70sSanO

I don’t think you have any concept of what you need to do to make that hub work.

The parts you need are 30-40 years old and are not available from any online retailer. You might find them on eBay. And if you can find them, there is no guarantee it will work.

On top of that, it is not just buying and installing parts. You have to re-space the wheel to be narrower and then re-dish it.

The only “theoretical” option I see is running all old Suntour Accushift 6 speed drivetrain with a Suntour 5 speed freewheel. 5 speed and 6 speed freewheels both have 5.5mm center to center spacing. In theory it should work, but in real life it may not. Or it may shift poorly.

My advice is to find a rear hub motor that fits your frame.

John

Edit Added: You could probably do the same with Shimano and Shimano 6 speed shifters. Those will cost more.

Geepig

All this is very interesting but rather theoretical. There are a lot of parts out there, but I still do not know enough to make any suggestions.

If you have the hub, then have you put it in the frame? Have you put it in the frame with whatever speed hub you already have? Did it fit?

For example, I have a folder and I will be fitting a new hub. At the moment it is not even built into a wheel, but this weekend I will be seeing if it will fit and, most probably, stretching the rear frame to take the new hub. Until hub meets frame, everything is just theory, because the chain might hit the frame for example.

70sSanO

OP said he needs to narrow hub by 1cm (10mm). I’m not well versed on e-bikes and doing a hub motor conversion. But if the hub is 10mm too wide, there may not be a lot of options. Supposedly his bike has an aluminum frame.

Since the OP has not let us know what the dropout and hub motor OLD widths are, we are just playing a theoretical guessing game. Not much is grounded in anything but speculation, without any actual numbers.

I believe the OP’s original solution was picking up those 10mms by going to a 6 speed freewheel instead of 7 speed.

John

alcjphil

OP doesn't seem to understand that changing the freewheel won't change the OLD of the hub

70sSanO

Yes. And we haven't even touched on the NDS. A hub motor assy that is slammed against the NDS locknut will yield no additional spacers that could potentially be removed.

John

luns

7 speed is spaced at 5mm, while 6 speed is typically spaced at 5.5mm. So, removing one sprocket from 7, reduces the width by 5mm, but then increasing the spacing to 6-speed spacing adds back 2.5mm, for a net reduction of 2.5mm. Not much. Technically, the 6 speed needs a little more overhang for its wider chain, but I don't think true 6 or 7 speed chains are even available any more, with 8 speed chains taking over for those applications, so this is a moot point.

Going to 5 speed would get another 5.5mm on top of that, or 8mm total. From a 135mm OLD axle, this gets to 127, which is close enough to 126mm it might work, assuming there are 8mm worth of spacers that can be omitted from the hub in question.

As for shifters, a 6 speed shifter would work fine for 5 speeds. The spacing is the same, and the low-gear limit screw when set appropriately (if it can be) will block out the last step. Limit screws could be a problem with 9 or 8 speed derailleurs which normally stop a range about 4mm wider. Might work, but might not. Probably best to stick to something designed for 7 or 6 speeds.

I don't think Shimano makes any 5 speed freewheels any more, but there does seem to be a 14-28 sunlite freewheel still available. It doesn't have ramps like modern HG sprockets, but indexing existed and worked before HG was invented.

first trip

hi when i search by component and rear derailleur, it comes up with a list. is this list in quality order? i

oldbobcat

A Megarange-compatible rear derailleur has an oversize jockey pulley. Like this one. https://www.moosejaw.com/product/shi...37912e52ba50a5

first trip

tx the does that apply to a 5 speed was about the Rder :@@ 6 and 7 speed systems are somewhat obsolete but since they used the same pull ratio as 9 speed, a 9 speed derailer will work..

so i ask would any 9 speed and lower work well for 5 speed?

first trip

HI
i already have my rays laces on my wheel with the hub, with a 7 speed we were lacking abit of space i maybe i ll borrow a old 6 speed to try and place it to see if the the space is ok before buying a new one, i still have to find a decent derailleur though..

first trip

if not 10 mm at least some yes

first trip

the old is over locknut dimension exact? that is the same thing as saying the dropout mesurement right?
the hub
the wheel and hub fit in my drop out yes but...... when i add a 7 speed freewh. it is too wide. that is why i search for less large
https://imgur.com/a/h1RPPr2

first trip

HI John i admit i dont know what nds mean if you have an image maybe i would get it . do you have one? could you paste it ?
tx

first trip

hi
did you miss frap cm for mm? idont get your @7 speed is spaced at 5mm, while 6 speed is typically spaced at 5.5mm. So, removing one sprocket from 7, reduces the width by 5mm, b
your post is very helpful iget the general idea but could you explain me what you mean by . but then increasing the spacing to 6-speed spacing adds back 2.5mm, for a net reduction of 2.5mm.. why increasing the spacing is necessary and what do you mean by this spacing of what versus what?

for the rest i understand that i could have a second choice by getting a used 5 speed adding 8 mm compared to a 7 speed. do i read you well?

first trip

HI wowo this info really is not to be overlooked! thanks for that i didnt know. I really would like a megarange. i looked at the spec and

what info do you use to say it is an oversized jockey pulley?

• Pulley Teeth - 13/13T ? what is the normal info for a non oversided jockey pulley?

70sSanO

NDS means Non Drive Side. It is the side of the hub that doesn’t have the freewheel.

All rims are centered between the locknuts on a hub. Typically when you change the overall width, you want to be able to reduce the width from both the side with the freewheel (Drive Side) and the NDS. It doesn’t have to be equal, but removing a significant amount from just the DS, or NDS, can effect the needed spoke length and there will not be enough, or too much length.

If your hub motor uses no spacers on the NDS, and you need to narrow the overall width by 10mm all from the freewheel side, there is a good chance the DS spokes will be too short and the NDS spokes will run out of threads.

Unfortunately you haven’t thought out what happens to the rim when you make the hub narrower. It is no longer centered in the frame. To center it you need to loosen the spokes on one side and tighten the spokes a corresponding amount on the other. If the amount you need to move the rim to center is greater than the spokes will allow, your wheel will be offset and may not even fit in the frame without the tire rubbing.

John