Going Single Speed

Fixxxer125

Hi guys
I've measured my road bike up (an old specialized allez) and I find the chainring is 130DCB (does this sound right for a standard roadbike?) I want to make this single speed for commuting, am I ok to get a track chainring for it ( http://www.ebay.co.uk/itm/Gebhardt-SINGLESPEED-TRACK-CHAINRING-130-135-144-BCD-42-43-44-45-46-47-48-49-50-/380583951072 ) or should I stick to something a bit more expensive but made for road bikes like ( http://www.ebay.co.uk/itm/Surly-Stainless-Steel-130mm-Singlespeed-5-Bolt-Chain-Ring-Road-Fixie-/120857788736 )
Cheers for your help
Alex

slowbike

My Spec Allez has 39/52 rings on 130BCD chainset.

You could change the ring for a different size, but not sure how you're going to get single speed working with the rear wheel drop out? (not saying it's not possible, just don't know how you do it!)

Fixxxer125

I was going to use a chain tensioner http://www.chainreactioncycles.com/Models.aspx?ModelID=58437, think I'm going to spend the extra money and get the Surly

slowbike

Ah - I see now! Hmm .... mind whirring now!

Monty Dog

Don't use a tensioner if planning to run fixed - IT WILL END HORRIBLY & PAINFULLY!

Yes, 130BCD chainring is normal Shimano road chainset size. Typical gearing for single speed would be 46/47/48 x 16/17/18 - depends on terrain and rider strength. You will be OK using a basic Stronglight chainring for a tenner from Ribble or Spa Cycles - particularly until you work out what gear you find best. You'll also need some single chainring bolts. Track chainring is 1/8" wide so would need a 1/8" chain which wouldn't run well with the tensioner - unless you're Chris Hoy, regular 3/32" road chain is plenty strong enough for road use.

cycleclinic

Also with a bit of cleverness running without a tensioner with vertical dropouts is easy.

Every tooth added or teken aways from the front or rear adds or remove's 1/4" from the total chain wrap required. So in any gear you pick if you are 1/4" from joing then chain then add or take away 1 tooth from the ftont or rear as appropriate. If that ratio does not suit then you can alter that ratio by add or taking away teeth so that you alter by a total of 0, 4, 8.. teeth and that corresponds to a change in chain length of 0, 1", 2" .. This way a suitable ratio can be worked out and then buy the appropriate chainring/freehweel or single speed sporcket. Doin it this way you get it right first time without wasted parts.

andrew_s

Dedicated single chainrings are better than generic gear chainrings because they have full size teeth with no gates that stop the chain coming off when there's no front mech to hold it on.
Some are also reversible so that when the ring gets worn you can turn it round and wear out the other side of the teeth.

I would recommend refraining from changing gear for a while before changing to singllespeed so that you can get a feel for how different gear ratios feel.