Singlespeed & Fixed Gear - My SS is almost done.. (pic)

I know, it's not a cool fixed track bike or anything, but anyway, my old steel Stumpjumper lives again! (at least, it will when i find some cassette spacers!)

Frame: 1993 Specialized Stumpjumper, Tange Prestige
Front wheel: original, with Specialized X23 rim, double butted spokes w. brass nipples, and LX hub. Bulletproof.
Rear wheel: 1996 XT rear cassette hub, double butted spokes w. brass nipples, Velocity K-525 rim (i built this wheel myself!)
Aluminum Softride stem
NOS Vetta Lite saddle
Sugino Impel cranks with the two smaller rings taken off (42t)
Chris King aluminum 16t SS cog (scored cheap on ebay)
Generic chain tensioner
1996 XT v-brakes and SRAM 9.0 levers
Control Tech ti skewers

Hanging off my homemade repair stand..

This is a very cool bike, and it's good to see something different here for once. It's alot like what my early 90's Trek will look like when it's finished (but not as nice!).

I'm thinking of going singlespeed mtb route, but first have to get my hands on a frame, and build me some wheels. Finding 28h mtb hubs at anything less than insane prices is easier said than done!

I believe loosescrews.com and a number of other places sell the spacers you are needing.

I believe loosescrews.com and a number of other places sell the spacers you are needing.

Yeah, thing is, they want $3 or more per spacer! That just seems exorbitant for an aluminum ring, especially since i'll need a bunch of them.

My LBS had more spacers than I could possibly use. Ask yours if they've got some old cassettes you can take apart if all else fails. You'll have more gearing selection then, too.

You could also shorten your chain once you get your gearing finalized and not have the tensioner pulling the chain away from the cog.

if I has that frame, I'd fix it with an eccentric hub and put upside-down uncut drop bars on it.

nice ride. i have that same frame, but purple :p.

that's a great ride - especially well suited for new york streets.

Is there a reason to have that much extra chain when using a chain tensioner? I would imagine you would want less chain and only use the chain tensioner to take out whatever slack is inherently there because of teh vertical dropouts? Am I being dense about this or is there some sort of advantage of running it that way?

By the way that looks really slick... I am in the process of rebuilding my old raleigh m-50 up in the same way more or less

Is there a reason to have that much extra chain when using a chain tensioner? I would imagine you would want less chain and only use the chain tensioner to take out whatever slack is inherently there because of teh vertical dropouts? Am I being dense about this or is there some sort of advantage of running it that way?


Maybe if he wants to be able to change gearing easily down the road?

Maybe if he wants to be able to change gearing easily down the road?


didn't think about that!

Yeah, thing is, they want $3 or more per spacer! That just seems exorbitant for an aluminum ring, especially since i'll need a bunch of them.

I've heard that there is a certain diamater of pvc pipe that can be used to space the cassette, but I've never tried it. I paid $25 for a set of spacers at lbs.

pretty sweet job man. love the colour.

working on a SS project myself. have a nice mavic wheelset and some sweet armadillo rubber with red walls to go with. also, that stem is being replaced with a quill, and some aero brakes to get rid of that cable clutter. just need the time now.

I've heard that there is a certain diamater of pvc pipe that can be used to space the cassette, but I've never tried it. I paid $25 for a set of spacers at lbs.

Yes, I've done that, but I forget the diameter. I'd only do it again with a pipe-cutting jig (and not just a vice and hacksaw).

Thanks for all the nice comments guys :)

Yeah, there is definitely too much chain right now. It's partly because i'm not sure of the gearing, but mostly because i'm struggling with this chain tensioner. It has a pretty strong spring, so if i make the chain shorter, it pushes down so hard that it actually makes the cranks hard to turn. But with a long chain like in the photo, there isn't enough chain wrap.

i started a thread about it in the Mechanics forum. I might take the spring out of the tensioner and rig it up backwards, pushing the chain _up_ instead of down.

An eccentric hub would be sweet, but i'm trying to keep this on a slim budget for now.

Oh, and the PVC pipe is 1 1/4" Schedule 40. I was looking for it today, and had some trouble finding it because apparently it's illegal to use it in Manhattan because of some building code. However, i found it eventually in a hardware store on 96th street, the one across the street from Metro Bikes or whatever. Incidentally, Metro Bikes claims they do not have any cassette spacers! I find that hard to believe, but i asked twice to make sure, and that's what they said both times!

If anybody wants some of the piping, BTW, let me know. I had to buy like 5 feet of it!

did either of you SS conversion peeps repaint?

The PVC size I needed was 1.25", oddly 1 1/4 did not fit. Go to a hardware store and see if you can get the 1.25". I went to Home Depot and they even had scraps leftover and the guy gave me about a 10 inch piece for free.

what does a 1 1/4" actually measure to, if that is nominal?

what does a 1 1/4" actually measure to, if that is nominal?
I'm going to guess I.D vs. O.D has some role here.

The PVC size I needed was 1.25", oddly 1 1/4 did not fit. Go to a hardware store and see if you can get the 1.25". I went to Home Depot and they even had scraps leftover and the guy gave me about a 10 inch piece for free.

I just checked the 1 1/4 piece i bought today, and it does fit, but it's very tight. A little sanding inside the tube and it should be perfect though.

Nice SS. I had a few of those old stumpjumpers, good hardy stock. I never got the thing with the suspended stems, is it good for you? I only tried em once and it weirded me out, but i think it was the elastomer Girvin stem or whoever not that one you got there. BTW an EBB would need a new BB shell on that bike so I think you're on the right track with the tensioner.

I've heard that there is a certain diamater of pvc pipe that can be used to space the cassette, but I've never tried it. I paid $25 for a set of spacers at lbs.

I'm sorry, but did you say $25?! Holy crap. You can get an el cheapo 7 speed cassette for less and have spacers and gearing. Buy two for a little more and get more than enough spacers and, if the ratios are different in the cassette, have all kinds of gears to play with.

At the LBSes here, enough spacers to fill the freehub would probably cost at least that. They are asking for $2 each for 1mm spacers.

SamHouston: the suspension stem is great for smoothing out chatter bumps and such. It's not really the same thing as a suspension fork. It doesn't help with big hits, but is great for the small to moderate stuff. I think they died out mostly because people thought they looked dorky, rather than because they were bad.
The Girvin you tried was a much inferior design with one pivot, so the handlebar and controls would rotate in a disconcerting way. The Softride stem has 4 pivots, so the bar moves in an almost straight line.


I solved the tensioner problem last night, BTW, by mounting it backwards, so that the spring pushes up:

Just wanted to add something that others might want to consider if doing the same thing. I just finished up the bike last night, cutting PVC spacers and tighteting it down with the lockring.

Two things:

1: get a 12t lockring, not an 11t. And 11t is almost too small. I'm using an 11, but it's barely catching the inner radius of the PVC spacer.

2: it's damn hard to cut the PVC pipe so that the ends are perfectly straight and parallel. I used a hacksaw and a hose clamp, but that ended up with a slightly angled cut. I filed it down as best i could, and got it to where the cog only wobbled a tiny bit, but it was annoying.
I'm thinking blowing $25 on spacers might not be so crazy, since it will probably save you at least an hour and you'll sleep better at night knowing that your rear sprocket is aligned perfectly.

Anyway, first ride on the born-again stumpy is today!

2: it's damn hard to cut the PVC pipe so that the ends are perfectly straight and parallel. I used a hacksaw and a hose clamp, but that ended up with a slightly angled cut. I filed it down as best i could, and got it to where the cog only wobbled a tiny bit, but it was annoying.
I'm thinking blowing $25 on spacers might not be so crazy, since it will probably save you at least an hour and you'll sleep better at night knowing that your rear sprocket is aligned perfectly.

Cheap plasitc miter box and a hacksaw. Like <$20 at home depot.

Cheap plasitc miter box and a hacksaw. Like <$20 at home depot.

Maybe.. but the miter boxes i've seen all have a cutting slot that is at least a few mm wide.. With the thin hacksaw blade, you can still easily get a cut that is 1mm higher on one side than the other, which is what i got with the hose clamp. I don't think i miter box is going to get a really precise cut.

Maybe a tubing cutting dealie would do the trick, although i'm not too sure how those work.