Hatchet

Hi all,

I've got an old ten speed with a freewheel (see pics) that I'd like to convert to a single speed (SS). I've searched around online, but don't see spacer kits for freewheels (if someone knows of any, please let me know). There are plenty of kits out there for for free hubs / cassettes, but I didn't see any for freewheels.

So - I had the idea of removing all the sprockets from the freewheel except for the one I want and replace all the other sprockets with spacers. Is this a completely daft idea, or somewhat reasonable and doable? I know someone who has a lathe that could grind down all the unwanted sprockets (after removing them from the freewheel) so that they in effect would become spacers.

Let me know what you think.

Thanks,
Dave

frankenmike 

BMX freewheel should screw right on to the old hub if your idea doesn’t work. May have to move hub axle spacers and re-dish for correct chainline.

fietsbob

yea that , done it myself including the dish change.. buy a single cog freewheel (they're mas from 16 tooth to 21 tooth)


you will be calculating your 1 gear with your math skills.. ratio X wheel diameter..

loosen the tight right side spokes tighten the looser left side spokes and rim moves to the left centering between the hub flanges

freewheel thread moves to the right... axle spacers center the hub shell equally between the axle ends..






/...

HillRider

Simplest is to just put the chain on the cog you want, discard the rear derailleur and cables, shorten the chain accordingly and let the unused cogs go along for the ride.

Hatchet

Thanks Frankemike, I had seen those BMX kits online. Wasn't sure if they'd work. Is there one in particular model/brand you would recommend?

Hatchet

Thanks fietsbob. I had read about this method as well, and is something I will consider.

Hatchet

That thought had occurred to me as well - and might be what I end up doing as I might eventually sell the bike and the next owner might not want single speed bike.

Thanks for the input.

Dean51 

I use a Sun Tour freewheel with just one cog on my singlespeed. To improve it's appearance, I machined two aluminum spacers with an o-ring between them to cover the area for the splined cogs. 'Was a fun project and it works great.

xenologer

What's the O-ring do?

Dean51 

At the time I was doing this, I did not have a single piece of aluminum large enough to make the cover from one piece. The two cover pieces have a small gap that is filled by the o-ring....the threaded cog compresses it a bit and keeps things from rattling. I assume a made for purpose single speed freewheel would be lighter in weight, but I made mine for no out of pocket cost from bits on hand. It was a fun project.

Dean

HerrKaLeun

besides just leaving as is, this is the best idea. you may keep the RD as a tensioner.

I don't understand a downgrade to single-speed idea itself. If you want just one gear, why not keep your drivetrain as is and never shift?

AnkleWork

Unfortunately that solution has a low hipness quotient.

Hatchet

Thanks for sharing the picture Dean. That is a very cool solution. I will look into doing something similar. To remove the sprockets off the freewheel, you needed two chain whips, correct?

frankenmike 

Shimano and acs are affordable choices that both work well enough. White industries is my current preference, but very expensive.

Dean51 

Hatchet..... Two chain whips or a "cog vise" and a single chain whip.

Dean

oldschoolbike

I have done the re-space and re-dish for a single freewheel thing several times without any issue. Starting with a cup and cone freewheel rear hub, you get a good chainline to the installed single freewheel by shifting cones and shuffling axle spacers from side to side, and then re-dish the rear wheel to centre the rim in your frame again. The result is minimal weight, no superfluous parts, and a very low, if any, residual dish in your rear wheel. The only cost is a mid-price single freewheel such as an ACS Crossfire. You can even put on a fixed cog and lock that on HARD with a steel English bottom bracket lock ring for the "suicide hub" version of a fixed gear, but make sure you really abuse it and that the whole assembly is damn tight before you go play in traffic. A few good hop-skids on dry pavement will let you know if you got it tight enough. A real fixed hub takes a left hand thread lock ring, which is secure.

Single freewheel is OK on a quick-release hub, but for fixed (suicide hub or otherwise) you really need a solid axle with hex nuts. You need horizontal dropouts in either case, to allow chain slack adjustment.

Some use a cheap single freewheel at first to confirm their gear ratio choice, and then get a decent freewheel once they are confident in their chosen ratio. At first you will often reach for a gear lever that isn't there. If it's usually to downshift, your single ratio is too high, and to upshift, too low. With the right ratio and some riding time, you will be in the single speed "zone" and never think about shifting. You will never be in the wrong gear, there is just no such thing anymore.

By the way, even my children are too old to be hipsters, and I have two single speed lightweights in service. A single speed or fixed gear lightweight is not about style, it's about experiencing the pure essence of cycling. You can ignore those who ask why you would strip the gears off a geared bike. They just don't get it.

squirtdad

+1