It might be a stupid question but here it is . Can the freewheel cog be removed and replaced with another fixed one ? I am currently running 48x16 mostly flat terrain and was just thingking to do a different cog on the other side just to switch it up . any feedback would be appreciated.

yes.

Awesome !! what size cog will you all recommend?

https://www.bikeforums.net/showthread...imer-for-Newbs

Not if the hub has freewheel threading on the side he's talking about. To install a fixed cog, you need both cog and lockring threading.

F me, you're right. Paging [MENTION=208564]striknein[/MENTION] to come and make fun of me.

Oh damn . oh well . thanks all .

If you have brakes, and use them, you can put a fixed cog on the freewheel side and use a bottom bracket lockring. I did this for a while until I had a wheel built with a fixed/fixed hub.
Avoid putting significant back pressure on the cranks because the lockring is threaded the same direction as the freewheel. Check the lockring often to be sure it is tight.

Actually @prooftheory was right... and wrong.

You CAN remove the freewheel and thread on a cog... but it'll spin right off as soon as you resist against the pedals.

Suicide hubs aren't really all that scary, as long as you run brakes and make sure you've got the cog threaded on tight. It's still better to buy/build a proper wheel with threading for a lock ring.

I still haven't quite figured out why they make fixed/free hub since you can thread a freewheel onto a fixed threading. Fixed/Fixed for president.

The ostensible reason is that freewheel threading provides better support for the single freewheel than a fixed cog/lockring threading. Whether this is a significant concern is a matter for debate, unless you're an animal pounding on your single freewheel.

The only reason a single freewheel body has more threads than a fixed cog is that the body is by necessity wider to accommodate the bearings and pawls, not because all those extra threads are needed. Since hubs were originally threaded to accept multi-speed freewheels, they were made wider as well. Considering the fact that track racers, particularly sprinters, tend to put out more power than road racers, yet don't strip the threads on fixed cogs and hubs proves that a fixed hub can adequately handle any load placed on a freewheel.

I like you, that's what I was going to write but without elegance or expertise. I guess from a cost stand point fixed/free hubs are easier to machine since you don't Haveto add the threading for a lock ring?

That'd be it. A bit like the change to aluminium frames. Once Tig welding became the manufacturing norm, it was cheaper to Tig weld ally than steel and so all mass production bikes became aluminium. This is ignoring the higher level bikes where they could make them lighter and that weight saving was indeed an issue.

Would it be correct to also say that it is easier to add a spacer if need be to the freewheel side to adjust the chainline. I don't know if it would be a problem to add a spacer to the fixed side since there aren't that many threads to begin with.

I had to add a 2mm spacer to my fixed/free hub because of the shimano 5700 crankset I'm using.

You probably have much better things to do than worry about your chainline being off by 2mm.

But how are you going to take the infamous chainline picture when it's not dead on?

Not eating asphalt seems like a pretty good reason. I've dropped the chain twice before when using a Sram PC1 chain and Shimano 3/32" freewheel. I don't run a lot of slack either.

Since adding the spacer, replacing the chain with a KMC 710SL and using a Shimano SF-1200 freewheel there have been no more issues.

I get tired of reading that 5mm or 7mm off is okay. I also think mixing 1/8 and 3/32" components isn't the best idea. It's just my opinion, so take it at that.

Well mate, there are many, many cyclists everyday proving your opinion wrong. If you're throwing chains, there is something else at work rather than a few mm of chainline offset (worn components springs to mind - just a thought, not an accusation). You're welcome to ensure that you have spot on chainlines and use matching components, I do myself on my good bikes, however, please don't add to the fear that many newcomers have of this game.

Sure thing. No more adding to the fear from me. Lot of misinformation out there that isn't coming from me. I'm just trying to help. I listen to good advice when I read it and some of it I got from here. I don't like the PC1 chain because it doesn't have chamfered inner plates. I use it on my single speed mountain bike and have never had a problem, but it has a decent chainline. I was rocking my road SS bike side to side with a lot of torque when the chain dropped. It was a newer chain too.

The PC1 has a bit of a reputation, not sure why. I've used them, only with a dead straight chain line mind, but what I didn't like was how it suddenly 'stretched' after a period of being good. I've since gone to heavier, track chains and they aren't giving me any issue at all (thank heavens, they can be pricey). Get a good chain and it's not changed often enough for price to be an issue, especially if you use more than one bike (ie, not one chain copping all the abuse).

The Sram PC-1 is the only chain I've ever broken. Never again.

I've never thought about it enough to put an actual number on it but in the grand scheme of things a few mm is never any kind of big deal. Look at how slight 2mm is on a ruler and try to honesty tell me it would make a difference. This bike had a chainline at one time that was off by at least a centimeter and I never came close to dropping the chain.

Most likely because your frame flexed (which would have still happened had your chainline been perfect). Think about it.

At any rate, this thread wasn't intended to be about discussing chainline.