Wanted: 12 tooth 1/8 sprocket

Does anyone have a cheap used or new 12t 1/8 sprocket they can sell me please?

Cheers

Pretty sure there's one in my stash.

Will let you know tomorrow.

Much appreciated. Thanks

If not, have a brand new DA 13 doing nothing.

I have a 13T thanks. I am trying to achieve the largest possible GI without buying a new Chainring

I know what you're up to MikeC...

just asking, do they make 11T?

So do I

he's trying to achieve the largest possible GI without buying a new Chainring

I know what you're up to MikeC...

ahha do you now?

just asking, do they make 11T?

i am finding it very hard just to find a 12 so I really doubt there are 11T out there. The only 12 I have found is from on-one. Its pretty cheap at only £13 but I am well skint right now and could do with a second hand one instead

So do I

he's trying to achieve the largest possible GI without buying a new Chainring

lol

just asking, do they make 11T?

PCD of an 11t x 1/2" sprocket is 45.1mm. The roller diameter (an therefore smallest possible chain height) is 7.7mm. That gives a root circle of 37.4mm. The thread OD is 34.8mm. If you designed a chain specifically to fit, and made the carrier part of the sprocket less than 1.3mm thick, you could in theory run an 11 on a standard sprocket thread, although it would be hellish trying to make a working lock ring. In practice, commercially available chains are quite a bit higher than the roller diameter, and even 12t sprockets sometimes need stepped lockrings to provide clearance.

11T you'd probably be bumping the chain on the lockring

Lock ring issues are not so, important as I will not be using this sprocket on the track or the road. youd have to be mad to do something like that ;)

Cock jewellery

Where do I collect my prize?

I will not be using this sprocket on the track or the road. youd have to be mad to do something like that ;)

You haven't told us what size chainring you've got; 32/12 is a pretty sensible road ratio, even if 48/18 is a better way to achieve the same thing

He's not trying to get a gear ratio for the the road though, or the track, or for a turbo trainer or for using after he is recomended a piercer.

Cock jewellery

Where do I collect my prize?

Ha you got me!

He's not trying to get a gear ratio for the the road though, or the track, or for a turbo trainer or for using after he is recomended a piercer.

I am basically trying to achieve a ratio that will allow me to build leg strength on my rollers with resistance. The resistance on these are not as strong as that on a turbo so I am looking to get a GI of at least 110. Would like to go even higher but for that I would need to buy a new chain ring and I aint doing that

Get a BMX hub with a 9t driver; I'm running 56/9 on the rollers. BTW, I've got a 12t x 3/32" Suntour you can have for a fiver.

If you hadn't gone and used it on the road, I could have swapped you that nice 46t zen you have for a nice big dura ace or zen ring.

I dont think it makes too much difference if its been on the road really. Every time I take it off I give it a wash down and it looks like new. Though I couldn't swap it as I need a low gear too.
I have chainrings from 46-49 and sprockets from 19-13 so I am able to achieve most ratios I need. I have a slightly wonky piece of shit from Condor 48T if you would like to swap that for a big 50+ one :)

Tempting. Bin my zen 48 and use a shit oval condor one instead. Sounds like a great deal, but I should probably sleep on it. :-)

Chainring to rear sprocket ratios can be achieved many ways, 48/18 sounds
a sensible starting point.
If you want to be critical about gear ratios don't forget to take the pedal crank
length into account as per Sheldon Brown's link below:
http://sheldonbrown.com/gain.html
It gets just a bit more technical than first thought!

Another thought; Would a 12 (or 11) teeth cog wear out really quick, more strain
on each tooth - the smaller the cog, distribution of force from chain on cog?

Chainring to rear sprocket ratios can be achieved many ways, 48/18 sounds
a sensible starting point.
If you want to be critical about gear ratios don't forget to take the pedal crank
length into account as per Sheldon Brown's link below:
http://sheldonbrown.com/gain.html
It gets just a bit more technical than first thought!

Another thought; Would a 12 (or 11) teeth cog wear out really quick, more strain
on each tooth - the smaller the cog, distribution of force from chain on cog?

did you even read the posts?

Get a BMX hub with a 9t driver; I'm running 56/9 on the rollers. BTW, I've got a 12t x 3/32" Suntour you can have for a fiver.

Cheers for the offer. I may take you up if I dont get hold of a 1/8.

did you even read the posts?

I don't think he did

did you even read the posts?

Yes I did!
Do you have a problem with a newbee posting Gizmond?

Just thought it would be OK on this forum to post an ocassional reply
and many thanks for the friendly gesture! Have a nice day.

I don't think he has a problem with newbies, but the OP knows what he's doing and just wants a 12t cog so he can use it to run a big ratio for training on the rollers.