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Changleen
09-04-2005, 06:17 PM
OK, Having just been quoted NZ$60 for a crappy no-brand single speed converter (you know the things, DMR and Gusset make them: http://www.jensonusa.com/store/product/CS611B00-Gusset+Single+Speed+Conversion+Kit.aspx)

And with no apparant way to ship one form the US for less than $40, I have decided to try and make my own. I have an XT cassette I can pull appart for the cogs, and also obviously the lockring, and thanks to Gusset I know the lengths of the spacers I need - 14 and 19mm.

So what I need to know from a :monkey: with a vernier caliper, what is the outside diameter of a standard freehub? Then I can just get down to the local hardware store and pick up a bit of pipe. I already have a pipe cutter. Anyone? I could measure it myself but if you happen to work in a shop and have a decent measuring device, I'd love to know an exact measurement!

BikeGeek
09-04-2005, 09:02 PM
I don't have an exact measurement, but I'm looking at Dirt Rag issue #115, p 87, "The Dirt Bag Way," where they are writing about different ways to convert to SS. Option #1 is using 1 1/4" PVC as spacers. Not the prettiest, but it gets the job done.

Changleen
09-04-2005, 09:05 PM
I don't have an exact measurement, but I'm looking at Dirt Rag issue #115, p 87, "The Dirt Bag Way," where they are writing about different ways to convert to SS. Option #1 is using 1 1/4" PVC as spacers. Not the prettiest, but it gets the job done.Awesome, Cheers! :) Any details about other options?

arboc!
09-04-2005, 09:09 PM
are you gonna be running a chain tensioner, or do you have horz. drop outs?

Changleen
09-04-2005, 09:23 PM
are you gonna be running a chain tensioner, or do you have horz. drop outs?My shizzle horizzle... Uh, horzontal I mean...

arboc!
09-04-2005, 09:28 PM
good good... i would suggest cutting the pvc into smaller sections, so you can get the chain line straight

rpk1988
09-04-2005, 09:29 PM
I like the Spot Spacer's. We have used those a couple of times at our work and they work out great. Make sure you get a nice cog and a chain that matches it or it will skip.

Changleen
09-04-2005, 09:32 PM
I'll be using a Shimano chain and cog at first, but I'd like to switch out to a more BMX chain in future, and a cog without shift ramps...

Changleen
09-04-2005, 09:35 PM
good good... i would suggest cutting the pvc into smaller sections, so you can get the chain line straightGood call. I'm a little dubous about PVC but I suppose the compression strength is the important factor so I guess it'll be fine. I'll look out for Alu tubing of the same size though.

arboc!
09-04-2005, 09:38 PM
Good call. I'm a little dubous about PVC but I suppose the compression strength is the important factor so I guess it'll be fine. I'll look out for Alu tubing of the same size though.
my spacers are plastic... all they have to do is keep the cog snug, pvc is fine

-dustin
09-04-2005, 09:44 PM
even if you could get those Gusset conversions, i'd advise not to. the spacers don't allow enough adjustment, in my opinion.

rpk1988
09-04-2005, 09:45 PM
True, the Gusset doesnt, but the Spot Brand one does add a lot of adjustment.

lux
09-04-2005, 10:31 PM
Good call. I'm a little dubous about PVC...

Had 1 1/4" grey (electrical) pvc on mine for years. Works great.

-dustin
09-04-2005, 10:38 PM
True, the Gusset doesnt, but the Spot Brand one does add a lot of adjustment.

yeah, that Spot one is nice looking.

Changleen
09-04-2005, 10:59 PM
Cool. Thanks for the feedback guys! PVC it is I guess. Save me $58 dollars I guess :)

BikeGeek
09-05-2005, 10:58 AM
Awesome, Cheers! :) Any details about other options?

The other 2 options deal with threaded freehubs and freewheels, so won't work.

For my first SS, I went to the LBS and asked if they had any throwaway cassettes. I took them apart and harvested the spacers. :) Another option is to ask for the aluminum track bike spacers. They come in 1mm-4mm and can be had for a couple of bucks.

Like others have said, the Spot kits are nice.

http://www.ridemonkey.com/mountain-bike-photos/data/500/42spacers.jpg

Changleen
09-05-2005, 03:53 PM
Mmm, that is pretty. Mine is all pulled appart now, I'm going to find some PVC tube for spacers in my lunch hour. I've got a bunch of spacers from the cassette I pulled appart, it's an old XTR as it turns out so the cogs are drilled out and cool looking, so I was pretty pleased about that.

I'll post a piccy or two when I'm done.

Oh, yeah, and I just have to let you all know, Profile hubs kick ass. They are so smooth, and so nice and easy to work on. Lots of superb little design features you don't notice 'till you take 'em appart.

Wumpus
09-05-2005, 08:46 PM
Remember running a cog off of a cassette can gouge up the freehub body.

ioscope
09-05-2005, 09:28 PM
Get a good cog if nothing else, I tried this whole thing once and it gets to be a pain in the ass.

Changleen
09-05-2005, 10:21 PM
I've heard about this - (the cog chewing into the freehub) - so I thought I'd use two of the spacers and attach them to the cog with cut down pins I'll secure with araldyte or superglue so the load is spaced over a larger area.

In the longer term, I think it is Surly that make single cogs with a wide base? I know I've seen them somewhere.

-dustin
09-05-2005, 10:38 PM
yeah, Surly, King, and Endless make wide-based cogs. Kings are too expensive in my opinion. the Endless is wider than the King, cheaper, and aluminum. i've got both and have yet to see any wear-difference between them. i don't know much about the Surly ones, other than they took damn forever to finally be released.

Changleen
09-13-2005, 02:28 AM
Gnar~!

http://www.ridemonkey.com/mountain-bike-photos/data/500/5626HubCloseUp.jpg

http://www.ridemonkey.com/mountain-bike-photos/data/500/5626Revell250RSS.jpg

(In my basement)

Awesome! :) I like. I've only ridden it for like 2 minutes rolling round in the road outside, but it's lovely to have no clunking deraillier. The bike is also a couple of lbs lighter (well maybe not) as an added bonus. I choose an 18T on the back because of the hills here, so it's gonna mean I have to get my spinning legs out again, if I can even find them. Sweet!

In the end I couldn't get spacers, but I went into LBS no. 3 which is roady focussed and normally pretty lame:

"Have you got any old casette spacers?"
"What for 9 or 8 speed?"
"Doesn't matter, I'm converting a bike to single speed."
"Oh, I have this then.." - And he pulls out a kit. $25! Sweet! :D

Edit: I forgot to say, chainline is pretty much perfect :thumb:

scurban
09-13-2005, 03:58 PM
such a nice bike! I totally agree with you on the whole light/stong/simple setup that a s/s dj bike offers! Very nice!

GumbaFish
09-13-2005, 04:25 PM
you can't go to your lbs and buy spacers? thats what i did, they have them in different diameters depending on wheter you have a 7spd or 8/9 spd hub and cost like 2 bucks a piece. I think i had to just buy a couple of those plus the spacers i ganked from an old cassette. also check here they have non ramped single speed specific rear cogs for cheap single speed stuff (http://www.sheldonbrown.com/harris/singlespeed.html)

GumbaFish
09-13-2005, 04:27 PM
woops didnt read your last post :eek:

Changleen
09-13-2005, 04:41 PM
I'm not sure they actually had spacers... :(

beans
09-21-2005, 10:51 PM
Hmm. Nice ride.:)