Ok.. in my endless quest for SS/Fixed knowledge.. I came across another question... what gearing should I use... I live in an area with some hills... as far as chainrings go I have a 52, or a 42... I'm thinking of using the 42.. and maybe a 16 or 18 in the back... any thoughts ?

also... if I get a BMX style cog... do they just thread on ? and if so will I also need a lockring ? if they don't thread on will I need spacers, since my hub is an old school style freewheel ?

Thanks

Jeff

p.s. Thanks for all the help in my other posts.. I have read all the links ya'll gave me... and they were great.. just need some more in-depth help :-)

Use the 42. If you use the 53 you will probably pop your eyes out on the first hill you attack, to say nothing of the difficulty getting going in the first place.
The 16 rear is a good all around gear of 71 gear inches on a 700cm bike. The 18, in my view is to easy. But maybe if you are just starting out it would be a good place to begin. Just definately leave off the 53 front ring for your next Bonnevile Salt Flat high speed Record Attempt.

Fixedgearhead

or you could locate an older bmx chainring with one set of holes for 110bcd and another for 130bcd. you can get them in pretty much any size between 43T and 47T...so like, 44.5T, 46.3333T, 43.25T....ANY SIZE! YOU BUY IT!

i have a 44/16 on one bike right now. it feels GRRRREAT!

You'll definitely be happy with a 42/16....

Sounds good...

any help on my other questions, regarding lockrings ? and freewheel hubs and such ?

JEff

I know that some people state that they ride without lockrings but I figure:Why tempt fate? Use one and you will never have to worry about the rear cog spinning off. Freewheels will thread on to existing track hubs with no problem and there is no need for lockrings as they freewheel and you can't put resistance on them by back peddling.

fixedgearhead

Good going, Jeff. We need more fixxers here in the Southland.

Ok... well since it is not a fixie... and it is not a track hub... can I just get a thread on cog (like a BMX cog? ) and thread it down snug on the hub ? I'm thinking against the lockring.. since, in my mind anyways, it is it's own lockring... at least the 11T cog that I pulled off my 6 speed hub was acting as the lockring...

Jeff

Maybe we can get a SoCal SS/Fixie meetup sometime... How many of us are there ? You, Me, Karsten... who else ?

Jeff

You can thread on a track cog. BMX cogs are either built into the freewheel or slide on BMX casette hubs. Neither is what you're looking for. For a bit of extra security you can screw the track cog on your hub and then after then screw on a BB retaining ring (or so I'm told, never tried it) and put some blue locktite on it. Word on the street is that it works fine. The reason that your freewheel didn't need a lockring is that it would coast, hence there was no force trying to spin it backwards.
Now that I think about it I'd just get a track cog with the appropriate number of teeth, crank it on there, then screw on that 11 tooth cog you have from your old cluster with some locktite and see how it goes. I'd run a brake for a while for a backup incase things go all wacky on you and decide to unscrew.

will I need spacers to cover the from the hub to the track cog, to keep it aligned with the chainrings ? Or is the track cog itself threaded ? The few I've seen on Ebay and such don;t appear threaded, just splined... am I looking at the right thing ?

Since I'm hoping to build it up using the freewheel, and hence, not a fixed gear... I'm not sure if I would need a retaining ring for anything other than extra security...

Jeff

p.s. Sorry if my questions seem lame... I'm just trying to get a good idea of what I need withough having to invest a fortune in a new hub and such

Hi Folks..

Ooops I think things got confused as to whether you were building a SS or fixed bike.
I've been reading this thread assuming you were still talking about your Centurion. If so,
for a singlespeed, you want to thread a BMX single cog freewheel (like ACS Claws) onto your hub in place of your existing cluster freewheel. There is no lockring issue for this type of setup as the freewheel prevents any reverse force applied to the cog.

For a fixed gear, you can do as familyman suggests.

I hope I didn't just make things worse

Thanks

jimv

ahhh perfect.. that is exactly what I was looking for !

I had a feeling that is what I would need.. just wasn;t sure :-)

JEff

OK, so it's NOT a fixie? No lockring required. If you put your chainring on the inside of the crank, assuming it is a double crank, the chainline should be fine. FWIW, personally I like Shimano ss freewheels. They just seem a lot quieter than other brands, even some more expensive ones. They also allow the use of standard 3/32" chains rather than 1/8".

We should meet up sometime and.. I dunno do something.

Sorry about the confusion, I was under the impression you were trying to 'fix' the bike. I guess I just added a bunch of confusion.
Yea, BMX freewheel, thread it on, you should be cool.

sweet... I'm psyched now... off to the bike shop at lunch ! :-)

Jeff

I run 42x17 on my converted ocr 3-- seems ok and might be good compromise between 16 and 18, might even be right between them.