# screw on cassette conversion to single speed?



## StillKeen (Oct 4, 2005)

Ive done a quick conversion of an old (circa 1989/90) De Bernardi to single speed.

It has suntour hubs (I think 6 or 7 speed).

I've not looked closely, but I assume they'll have a screw on cassette?

I have never touched a screw on hub, and know nothing about them.

What are my options for converting it to a single speed wheel? Currently we've just got the chain sitting on the cog it best lines up with.

Thanks in advance for the help.

-Chris


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## JCavilia (Sep 12, 2005)

*screw-on freewheel*

That's the proper term -- not "cassette". With the proper tool, you can remove the whole freewheel, and then thread on a single-speed freewheel. It can be hard to remove a freewheel that's been stuck on for a long time, but it's doable. Sheldon has lots of tips
http://www.sheldonbrown.com/singlespeed.html
The chainline will probably need adjustment if you do this, which means you'll need to re-space the axle and then re-dish the wheel. Not that hard if you're a little mechanically inclined.

The way you've got it now is the simplest way, but it looks a little inelegant, if that matters to you.


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## addict42 (Nov 2, 2006)

You might be able to space a SS freewheel out a bit with some freewheel shims instead of re-dishing your wheel and swapping spacers. You can find them here:

http://aebike.com/page.cfm?action=list&PageID=30&category=551&modelId=2590&type=T


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## StillKeen (Oct 4, 2005)

Thanks for the info. A few more questions now.

1) I bought a screw on freewheel for my fixie, and havent used it. It was to fit a PhilWood hub. Will this fit onto the older wheel?
2) So back in the day, when the rear cogs wore out, did you have to replace the freehub mechanism too, or are the separatable?

If my existing singlespeed freehub fits, I would like to experiment with mounting this using spacers. I would prefer not to have to redish the wheel. I've built a few wheels, but I'm not overly competent in my skills with wheel building.

If someone has a photo of an older wheel that's been modified, or better yet pictures of the process, that would be fantastic.

thanks.


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## JCavilia (Sep 12, 2005)

*a few answers*



StillKeen said:


> Thanks for the info. A few more questions now.
> 
> 1) I bought a screw on freewheel for my fixie, and havent used it. It was to fit a PhilWood hub. Will this fit onto the older wheel?
> 2) So back in the day, when the rear cogs wore out, did you have to replace the freehub mechanism too, or are the separatable?
> ...



1. Yes. the thread is the same./

2. You can replace cogs on a freewheel, but it was a bit of a hassle.

3. If you use spacers, don't overdo it. You need to be sure enough threads engage.

4. If you've built wheels, re-dishing is no biggie. It's just a glorified truing job, loosening one side and tightening the other until the rim is centered. Re-spacing the axle is actually the more laborious job, IME.

5. Check Sheldon for details, maybe pictures.


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## Spinfinity (Feb 3, 2004)

Most all freewheels are the same. I think Motobecane made some that were different.

Freewheels are cogs on a mechanism that allows coasting. On newer bikes, the cassettes are fixed and the hub contains the mechanism that allows coasting. When cogs wore out it was possible to replace an individual cog or cogs, but seldom the practice. I always got a new freewheel with a new set of cogs on it. 

You can't easily make a freehub fixed, but the older hubs will take a fixed cog, freewheel cog or multi-geared freewheel.

Screw the cog onto the hub. Mount the wheel on the bike. See how the chain line looks. Many cogs come with different size flanges on either side which allows a little adjustment for the chain line. Get the chain line as close as you can to straight. Dish or undish the wheel as much as you need to. This is simple stuff that makes sense once you start doing the work.


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## blackfire (Jun 15, 2007)

I converted a 1984 Centurion over to a SS. I ended up just lining up the gear and crank so the chain line is straight. I was told it was next to impossible to convert it with a rim that is so old. The LBS told me to get a new rim.


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## StillKeen (Oct 4, 2005)

Update:

Went to the LBS, and they nicely removed the old freewheel for free. I went home and cleaned everything. After fitting the single speed freewheel, I proceeded to dish the wheel (possibly 1 or 2 mm overdished ..).

Problem. The non-drive-side spokes are just sitting proud of the rims inner wall .... where the rim strip goes.

Soultions:

1) Put less dish in the wheel. - Won't work so well, as the frame has minimal clearance.
2) Use 2 or 3 rim stips - I would expect this will just delay the spokes rubbing into the tube and causing punctures.
3). Replace the non-drive-side spokes with ones 5 mm shorter.

I'm thinking its going to have to be #3.

Thoughts anyone?

Thanks,

-Chris


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## threesportsinone (Mar 27, 2007)

Will velo plugs work? 

Its worth a try and if they don't work put them on a different wheelset.


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## StillKeen (Oct 4, 2005)

It will be close, but I think they might just work.

I've forwarded the email to my buddy who's bike it is that I'm working on, see if I can convince him to order some.

thanks


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## 10ae1203 (Jan 14, 2007)

can't you cut the spokes off flush w/ the top of the nipple?


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## Reynolds531 (Nov 8, 2002)

StillKeen said:


> Update:
> 
> Went to the LBS, and they nicely removed the old freewheel for free. I went home and cleaned everything. After fitting the single speed freewheel, I proceeded to dish the wheel (possibly 1 or 2 mm overdished ..).
> 
> ...


you could do the brutal apprach of using a dremel to grind down each protruding spoke I've done it. it worked


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## Richard (Feb 17, 2006)

Reynolds531 said:


> you could do the brutal apprach of using a dremel to grind down each protruding spoke I've done it. it worked


Yep. Just make sure (back a nipple out to see) that you have enough threads still in the nipple. We've done it more than once.:thumbsup:


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## StillKeen (Oct 4, 2005)

I was thinking about the dremel ...but wasnt sure what cutter/wheel to use to get in there.

The velo plugs are 15 euro + 3 euro postage.
16 spokes would be about $US16
Dremel = free .... 

Thanks.


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## Thommy (Sep 23, 2003)

*Grinder*

At my buddies' shop we would take the wheel over to the bench grinder and remove the extra spoke material. Do this lightly so as not to grind down the hoop (rim) then follow up with a file to deburr any little sharp edges. Use a good quality rim strip such as Velox, carried at Performance Bike stores. My 2.5 cents (inflation, don't you know).


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