Building a Fixie from a Vintage Frame

Hi all

I am currently intending to buy a bike frame so I can build up a bike myself  (a single speed/fixed gear with a flip flop hub as a little project) to increase my bicycle knowledge. I ride a 55" to 57" depending on the frame and have been reading Sheldon Brown for  a while now. I have a work stand and a range of tools (mainly.park) to build up a bike. However, I haven't tried building up a bike completely from the frame up.

For simplicity of build, do you think that I should choose a frame (track) to that has 120mm OLD so it fits most flip flop hub dims? Or a vintage road frame (may have 126 or 130mm OLD) AND then add spacers...not sure if this would be difficult to get a good chainline for a novice like me.. .

I have noticed that rear drop outs for some vintage road frames are at a slight horizontal angle ... more so than others, will this mean it will be harder to achieve a desirable chain tension?

Would love to hear all your opinions and advice…!

Hi I’ve had 3or 4 vintage frames converted to SS with 126 rear dropouts and chainline has never been an issue, these frames have had the more horizontal dropouts as you’ve described
I’ve only been using freewheel so again no issues of wheels dropping out
good luck

From my understanding, chain line will be the same on any frame as the centre of the seat tube, bb, wheel etc is the same and it's just the chain/seat stay that is wider from the centre. Best I could describe it! Sorry if it's bad.

Adding spacers shouldn't affect that alignment.

As for the drop outs giving enough space to tension the chain, I have minimal experience in that, sorry.

There’ll be tons of threads on here covering chainline. Old steel frames can usually stretch in or out to accommodate different size hubs OK.

It’s showing its age now but ‘Puma Fixed Gear 101’ got me through my first conversion builds many many years ago

https://www.mediamatic.net/image/2016/12/13/puma_fixed_gear.pdf

Most road frames up to the 90s ish will have forward facing dropouts with enough travel to tension the SS chain. If your wheel OLD is less than the dropout spacing (126/130) then yes you’ll need spacers. Bear in mind adding spacers ‘correctly’ requires a set of hub spanner’s to remove the outer lock nuts without buggering up the bearing setup. Then choose a Bb length to get the right chain line - which is usually a trial and error plus some maths process( in my experience ) unless you know the BB length/chainline of the chain set you’re using. It’s all doable and I’ve done it but there is simplicity in using a track frame and wheel with an OLD to match. But then it’s also a matter of frame geometry, what you want to ride and what is available to you.

It's entirely possible to use a 126mm OLN frame with a 120mm wheel. Just bend it a bit to get the wheel in or cold set it (check Sheldon) for a more permanent solution.

chainline is dependent on the distance from the cog to the centreline of the bike so assuming your rear end isn't off centre somehow, it's more a function of crankset and rear hub choices.