Freewheel question
 

So my ignorance runs deep with free wheels. Currently my new to me bike has suntour friction shifters, a Sachs Huret duopar eco RD and a suntour 5 speed freewheel.

What is the largest number of speeds on a freewheel can I use with my setup?

I have found a 27” wheel set with new gatorskins and a 6 speed Shimano freewheel for roughly the price of the tires and want to make sure it would work.

If it's a 5sp, your bike probably has a 120mm spaced rear, and the wheel you're looking at probably is 126mm.... You could probably just squeeze it into your frame... or if it's a steel frame, spread the dropouts to 126mm. And if you spread to accommodate 126mm, you can likely fit a 7sp freewheel.

A good starting point would be to measure the OLD of your current hub, or the spacing of the rear dropouts- then you'll know where you stand, what you'll need to do to get more speeds, etc.

Velobase says that RD has 36T chain wrap and 36T max cog size: https://velobase.com/ViewComponent.a...67ba9&Enum=108
That means it will probably handle most any freewheel.

Given you've got a Suntour 5 speed on there I'm guessing the dropout spacing might be 120mm.
You need to measure that before anybody can give a final verdict.

I've built a wheel with a 7 speed Sunrace (13-28) freewheel that fits a 126mm OLD (6 speed) bike, it works very nicely (Suntour Cyclone Mk2 GT RD, Suntour Power Shifters).

A 5-speed hub will have a 120mm OLD (over locknut distance; i.e. the distance between the inside faces of the rear dropouts. With the exception of Suntour Ultra-6 freewheels, a standard 6-speed freewheel will have a 126mm OLD. This means that you will need to spread the rear stays apart by 6mm to get a standard 6-speed wheel in there. Some folks simply pry the stays apart and jam the wheel in. This can work, but the resulting non-parallel dropouts will then cause extra stress on both the dropouts and axle, which can result in a broken axle and/or cracked dropout (both of these problems have happened to me). Alternatively, you can have the frame spread by cold-setting and then realign the dropout faces to parallel. This can either be done at a competent LBC with the correct tools, or by following Sheldon's instructions here: https://sheldonbrown.com/frame-spacing.html

Another solution would be to find yourself a used Ultra-6 freewheel and narrow chain (any 8-speed chain will work) to put on your 5-speed hub. Less chance of axle breakage that way too.

If I have the bike cold set and if I chose to go back to the stock wheel set, would I need to put spacers in to accommodate for the new width?

Yes if you want the dropouts to be aligned correctly. Not a big deal though.

What bike is this? I've seen plenty of 5 speed setups on 126 frames.

1985 Schwinn Voyageur SP. I measured the distance with the wheel on it presently and it measures right about 123mm

That's a good compromise distance between 120 and 126. That year was fairly transitional between 5-speed and 6-speed freewheels which is probably why they did that. Sounds like you are good to go with either wheel set.

Basically, you can run a five cog or a 7 cog freewheel. You can even run an 8 cog freewheel, if you can find one. To run an increased number of cogs freewheel, you will need to equally spread your stays and install a longer rear axle. That's about it buy my question would be why bother? Five cog freewheels are just fine and are used with shorter axles, reducing the possibility of an axle bending or breaking. Also, five cog freewheels come in a wide range of cog sizes, offering decent gearing ranges (important to my really old and worn out legs). The one drawback that might present itself, is the cog tooth design. I prefer the angled teeth but most five speeds don't offer that option.

If you have the original Suntour sealed bearing hubs- you may not be able to get the freewheel on- I have an 84 Voyageur SP and a 6 speed just *starts* to thread before it runs out of threads.

That being said- there's a lot of good 5 speed freewheels out there in a lot of good cog choices.

Personally I run a lot of half step and granny. 5 speed with a modern 8 speed chain runs that real well. 14-17-20- 24 28 will do nicely. 14-17-21-26-32 is even better.

Thank you for The info.

Borrowing an existing thread... I would like advice/opinion on replacing the SACHS six-speed freewheel on my Riv. It's a Phil hub, the frame is spaced 130mm, and I'm running 13-30 cogs, they're spaced 5.5mm. Pretty sure it's ISO threading. It's 25 years old, so overdue. What are good options in 2023 for replacement freewheels? N.O.S. looks to be available on ebay, but are there new or recent innovations to think about, maybe freewheels with more pawls? And any reason not to look to a seven-speed hub, with 5.0mm cog spacing? I know there are good narrow chains available.

Thanks...

All my bikes are friction, so I can't speak to the specifics of the spacing between cogs, but with a 130-spaced rear you ought to be able to go to 7-speed without changing the hub. The best shifting I've got is the bikes that have the cheapie Sunrace 7-speed freewheels, which I think are more or less Shimano knock-offs- at least the tooth profiles, etc, look like Shimano. That's with KMC 6-7-8 speed chains- I think they're something like X8. Cog ranges are a little bit limited, and unfortunately the all-silver Sunrace freewheels seem to only come in 13-28- if you need a bigger low cog you're stuck with fugly-looking black. The old Suntour NWN freewheels I've got feel like much higher quality pieces of gear, but the Sunraces shift better, and you can't really beat the price.
I definitely recommend against the IRD freewheels....

If you go 7 speed know the sunraces are usually a hair wider than Shimano. This can cause fouling at the dropout. Both have worked well for me but I prefer old suntour models when I can find them.

Post us pictures of your 6-speed Sachs freewheel. It might still have plenty of life and only needs a good cleaning and servicing. I'm guessing a 7 speed Sachs Aris freewheel could be the perfect upgrade and if needed I can help you out.

Take the wheel out of the frame and measure the distance across the flats on the inside.

I'm betting this will be the 126 mm not 123 or 120 mm, based on the 1985 build date.

Only a measurement can resolve this.

Better to start a new thread unless you are referring specifically to items earlier in the thread. It just get confusing mixing old posts and new posts.

Several of the cog teeth are worn, and chain occasionally floats over cogs. I don't use indexing, just pure friction all these years.

https://photos.smugmug.com/Bici/Rive...IMG_3869-L.jpg

https://photos.smugmug.com/Bici/Rive...IMG_3870-L.jpg

By any chance do you have the tools to remove the freewheel from the hub, and the sprockets from the freewheel body? If so, let's begin with doing so and cleaning the sprockets and posting more pictures. We need to take a look at their spoke side, which will show excessive wear better than the outside.

On which sprockets does the chain "float"? Also, what chain are you using and how old is it? In my experience, these freewheels play nicely with a new KMC or SRAM 8-speed chain.

Finally, is your RD aligned well, clean, and lubricated?