Stupid question about flip-flops

Lumen

So, I got a fixed cog put on my Singlecross.

15 teeth of Dura Ace goodness, 'cos I don't need no stinkin' cadence.

However, my freewheel cog has 18 teeth.

The obvious problem is that these cogs have different circumferences, and the chain is currently sized for the 18. When the 18 is used, the skewer and bolt are right at the end of the (horizontal) droput, which looks a bit dodgy.

If I shorten the chain to fit the 15, I won't be able to use the freewheel.

I'm left with the following options:

A. Keep the chain long, retain use of both fixed and freewheel, hope the back wheel doesn't fall off.
B. Shorten the chain and lose the use of the freewheel.
C. Use two different chains.
D. Downsize the freewheel cog. Forget about hills.
E. Buy some sort of chain tensioner. Lose hipster points.

I know that this is probably like a zen thing, which will make me totally connected to the bike, but it is nonetheless a PITA.

Morgan

Oh, thought this was a footwear question.
Can't really help with that bike stuff.

E isn't an option on a fixed-gear though.

How frequently are you likely to be switching the wheel around - that could decide what's the best option for you.

Gavin

Get one of those half link wotsits?
http://www.sjscycles.co.uk/product-Unbranded-Chain-Half-Link-1-8-Inch-6981.htm

edit. I'm confused. Get a 17t freewheel. This will make you tougher too.

TinyExplosions

There's no easy way if you want to switch between fixed/free except for getting a similar or identical size on each.

Otherwise, it's shortening your chain that's necessary!

Lumen

Cool, thanks.

That half-link looks useful.

flickerx

Yeah the half link for the chain is excellent for getting the wheel at a decent place where you can flip it around without it being too tight or loose for the dropouts. But I'd recommend getting a smaller freewheel, the gearing ratio looks pretty low to me, I think you'd be fine with a 15 or 16t. Bear in mind of course as well that every time you change over your back brakes wont be aligned properly, you can get away with this usually if there's just a one tooth difference in the cogs, but anything more and you'll risk rubbing the brake pads up against the tire when you flip it over.

Lumen

flickerx wrote: »

Bear in mind of course as well that every time you change over your back brakes wont be aligned properly, you can get away with this usually if there's just a one tooth difference in the cogs, but anything more and you'll risk rubbing the brake pads up against the tire when you flip it over.

Oh yeah, I found that out too!

Greyspoke

Single speed chains are dead cheap - I reckon the best solution is just use two different length chains and swap as needed. They often come with quick release links (the one on the Tricross does) so it'd be a very quick job to change.

flickerx

Greyspoke wrote: »

Single speed chains are dead cheap - I reckon the best solution is just use two different length chains and swap as needed. They often come with quick release links (the one on the Tricross does) so it'd be a very quick job to change.

I don't recommend doing this.

DirkVoodoo

Two equally sized sprockets is the way to go. I still haven't touched my fixed side, the flip side. Maybe its the flop side.

steinone

Okaii... well on my fuji track I had a 48-15 ratio.... not good so I thought that 18 on the back would be better, with the 15 on it was just past the half way point of the dropouts(twards the outside) when I put the 18 on to my surprise it sat just off the back of the dropouts with no need to change anything to do with the chain.
If you are saying with the 18 on it sits near the back wall of the droputs thats fine...

souter

I've got the singlecross with 48/15 fixed, flipside is 18 freewheel. Swap them about from time to time and chain is just fine (i.e. hasn't fallen off yet). Brakes? I don need no steenkin' brakes! Or back ones at any rate, just use the front ones and don't bother adjusting the back pad alignment.

Gavin

steinone wrote: »

Okaii... well on my fuji track I had a 48-15 ratio.... not good so I thought that 18 on the back would be better, with the 15 on it was just past the half way point of the dropouts(twards the outside) when I put the 18 on to my surprise it sat just off the back of the dropouts with no need to change anything to do with the chain.
If you are saying with the 18 on it sits near the back wall of the droputs thats fine...

He has horizontal dropouts, you have track ends

niceonetom

Verb wrote: »

He has horizontal dropouts, you have track ends

i think the singlecross has track ends. no?

lumen, unless you are actually going to go mud racing when are you ever going to need a 42x18 singlespeed? that ratio is very very spinny for the road.

bin the freewheel. fix 42x15 fo' life yo.

@Lumen - i have a 17t (i think) free wheel you're welcome to that might be more usable if you really really insist on coasting. might lessen the chain length problems too.

edit - if i can find it!

Gavin

niceonetom wrote: »

i think the singlecross has track ends. no?

Hmm the site says horizontal dropouts, but they look like trackends in the picture. Can these website buffoons not learn the correct terms dagnammit !

If they are trackends on the specialized, I am confused again.

Lumen

Oops. Terminology fail on my part.

The singlecross has track ends (i.e. horizontal dropouts open at the rear).

rp

Morgan wrote: »

Oh, thought this was a footwear question.

me too: SPD sandals are fine, but flip-flops? Though I guess they'd be handy for those winter training holidays in Ibizia: off the bike and straight into Pacha...

souter

souter wrote: »

I've got the singlecross with 48/15 fixed, flipside is 18 freewheel. Swap them about from time to time and chain is just fine (i.e. hasn't fallen off yet). Brakes? I don need no steenkin' brakes! Or back ones at any rate, just use the front ones and don't bother adjusting the back pad alignment.

Sorry, a bit facile there. You need to remove a link or half link. Sheldon Brown site has the calculations somewhere of I think of .5" chain per tooth. 18 to 15 makes 1.5", which is about the length of the trackends so I'm just lucky to fit the 15 slightly slack and 18 slightly tight w/o adjusting the chain.