[GiantRider]

I would like to convert one of my old mt. bikes over to a single speed, and was wondering if anyone had any advice . I really need to know if i will have to buy a diff wheelset and cranks or if i can just toss the der. and extra sprokets.Any help would be great.

 

[Dirty]

go to your local shop, and ask for some old cassette spacers...not sure how many youll need...then take appart your current cassette, pick your favorite sproket, use the spacers and lock ring and find your ideal chain line.
if youre running 3 rings upfront, youll usually run the middle for a single speed. can leave the other rings on if ou like...doesnt matter..

but no, you do not need a new wheel or cranks...
but youll need cassette spacers, 1 cog, shorten your chain, and possibly some sort of chain tensioner...

 

[BikeGeek]

The rear derailleur can be used as a tensioner if needed. Run a piece of brake or derailleur cable through the barrel adjuster on the derailleur so that the metal cable end sits inside the adjuster. Fix the other end of the cable to the fixing bolt on the derailleur. Eye up your chainline, pull the cable tight, and tighten the fixing bolt. You can use the barrel adjuster for small side-to-side chainline adjustments.

http://www.ridemonkey.com/forums/attachment.php?s=&postid=620539

 

[EBasil]

I converted my old HT late last year, and have a few suggestions:

--You don't need new cranks, but you might want some "BMX chainring bolts" if you decide to run without a "bash guard". I think you'll find the best chainline is going to come from your middle ring position, not to mention the gear ratio you want.

--Start with 2:1 ratio and adjust your build to accomodate your local riding area. Call local shops or riders and ask what's working there. I went 34/18.

--Since you can use a spacer kit and a cog on your old cassette hub, you can set your chainline perfectly.

--I went with an un-ramped rear cog, because they're thicker and more durable in appearance. Same gig with the ring, up front. I took this advice from a really hardcore SS rider, and also from a former Cal State SS champ. Works so far.

--I had to use a "tensioner" and went with the Surly Singleator which includes options to push the chain up (ie more chain wrap on the cog) or down (less chain wrap, but more chainstay clearance). I've found that the "push up" method works a lot better under power, and suggest you look for tensioners that provide for it --not all do.

--look for wider bars. You'll be out of the saddle a lot more than before.

 

[Westy]

Like everyone else recommended just use spacers and a single speed rear cog like a King Cog. I have used both an old derailleur and a surly singulator for a chain tensioner. If you are lucky your chainstay is just the right length to not need a chain tensioner. That will require the right gear combo and you may need to use a BMX halflink. to stop your chain from dropping use a single speed specific front ring like a blackspire DS ring.

 

[GiantRider]

Great advice monkeys, many thanks, i am in the process of tearing the bike apart now then i will prep it for paint.I will make a trip to the bike shop to look for a ten. and front sporocketas well.