HowTo? Fixed / Singlespeed conversion from an old bike

yes

maybe...

no

pick one answer.

bah.

Will go on but chainline might be wac unless you respace and re-dish.

Maybe

Yep but I doubt very much it is a five speed cassette, more likely a five speed freewheel, hence why you have linked to a single speed freewheel. You may need to reddish though.

If it is a five speed cassette you will need

five speed free wheel, thats what im talking, cheers guys.

five speed free wheel, thats what im talking, cheers guys.

i'm a lady.

All done :)

Took her out for her maiden voyage today. Beautiful day. Got a few snaps when I reached my destination (puffing and panting, just chucked it against a nearby tree). I'm VERY pleased nothing fell off...

If anybody is interested in the full list, prices and sources:

Frame seatpost saddle fork handlebars - £10! (ebay)
Chainset £9.99 (ebay) Some campag double chainset, took the inner chainring off. Good chainline demands chainring on the inner however (ugly, but meh)
Wheels (rims hubs spokes building shipping) £110 (ebay)
Sprocket £10.99 (wiggle) DA 15T
Pedals £9.99 (ebay) Look
Lockring £5.50 (hubjub) DA NJS
Brake cable £4.25 wiggle
Tyres tubes £20 (cyclingbargains) Vredestein ricorso + continental tubes + leccy tape
Chain £5.99 (chain reaction)
Brake lever/callipers (free) off an old bike
Comedy "bugle-style" horn £3? (ebay)

=£189.71

(And probably half that again on tools...)

I'm extremely pleased. Thanks lfgss, and Sheldon Brown.

ps. never had to file anything, just apply a lot of force. Very snug fit.

3 Attachments

That looks like a huge gear ratio. How big is the chain ring?

Nice, needs bartape though

That looks like a huge gear ratio. How big is the chain ring?

52T. Even a slight incline is a challenge. But I hardly ever experience any on my usual routes.

Nice, needs bartape though

Thanks, but nah. Liking the scratched up alu look for now.

Shit, that's over 90 gear inches. get a 19 or 20t cog on the back and get it down to 70-is and you'll like it a lot more.

Shit, that's over 90 gear inches. get a 19 or 20t cog on the back and get it down to 70-is and you'll like it a lot more.

(Without having a test ride of 70-80 GI I can't really say this but) I'm quite liking the ridiculous potential for top speed at the moment. Just getting my leg power back to what it used to be...

(Without having a test ride of 70-80 GI I can't really say this but) I'm quite liking the ridiculous potential for top speed at the moment. Just getting my leg power back to what it used to be...

Thats a nice build, well done.

But seriously thats a massive gear! for street riding i would recommend you change the sprocket. Its going to mash up your knees.

You don't need 90" in the street, that's craaazy. Plus you can get over 30mph easily enough on ~75", do your knees a flavor.

Alright alright. But I really like cruising past other cyclists at 70 rpm...

So I would need either a larger sprocket (18T) or smaller chainring (43T...)

Recommendations for a 3/32 18T sprocket?

Looks like a nice build, I hope mine looks like that :) Don't listen to what they say about the gear ratio, if you're happy with it and you live nowhere near any big hills, keep it. Oh and if you are going to change it I would recommend changing the rear sprocket rather than the front :) Just a thought

Luke

Meh. Under cadenced. grumble grumble
I guess you must like them spinning past you again at the traffic lights though? :)

Anyway, I'd go for a 1/8 sprocket and chain. You can run it with a 3/32 chainring no problem.

Alright alright. But I really like cruising past other cyclists at 70 rpm...

So I would need either a larger sprocket (18T) or smaller chainring (43T...)

Recommendations for a 3/32 18T sprocket?

You could always just plant on the smaller chainring from the chainset, I'm assuming its a 42 tooth, just to try it out, cost you nowt (except for cutting the chain)

i've read all of sheldon brown but my maths is terrible. should i use my 50 or 36 tooth chainring for a single-speed conversion with a 16 tooth sprocket? i know around 42 is ideal but i cant afford a new chainring.

i'm not super fit so i'm drawn to the 36 but i also hate frustratingly low gear, obvs.

thoughts anyone?

try 36/16, if it's too spinny get a smaller rear sprocket

best to change the brake levers though, they're called suicide levers for a reason.