My First Fixie Build

Hi everyone, just wanted say what a great forum!

So I’m trying to put together my first fixie for a bit of fun, it’s actually the first bike I’ve ever built so I’m hoping to learn a thing or two! I’ve got a 27" Schwinn Voyageur SS that I love but have been dying to try a fixie!

Frame
First thing was an old Graecross frame. It’s got more rust on it than I would’ve liked, and there was rust on the seatpost when I took it out. So first questions:

What’s the best way to get rid of surface rust without damaging the paint?

What’s the easiest way to treat the rust inside the frame? I don’t think I’ll keep the frame forever so I want something cheap and easy if possible.

Crankset
I’m just going to use the one that came with the frame. The cranks are 17cm from centres (is that the right measuring point?). I the bike came with a 39 chainring and I’ve bought a 15 tooth Origin8 cog. The chain is a 1/8" Origin8. I realised after it was delivered that that’s probably too wide for my cog… is that right?

Wheelset
White Weinmann DP18’s. CST White Super HP Nylon 700c Bike Tire (cheap!)

Other Bits
MKS Sylvan Classic Fixed Gear Silver Track Pedals
NJ5 Toe Clips Leather Straps SILVER
Origin8 Track Saddle WHITE
Origin8 Pro-Stash 25.4mm 48cm Silver Handlebar
Origin8 Pro Pulsion White Rubber Track Bike Grips

So now it’s all about me getting rid of the rust, trying to remove the bottom bracket, polishing some parts and putting it all back together (not looking forward to trying to do the chainline).

Comments, advice, and constructive criticisms welcome!

Sounds like some exciting times ahead! Building a bike from scratch is very rewarding, and you will realise this when you go for your first ride after negotiating all the little problems you will come across. I was in the same boat this time last year and found a lot of people helped me out when I needed it.

Post some pics of the rust and the frame if you can.

Thats fine - the 16t cog you have won’t allow you to use a thinner chain anyway. There will be a little movement on your (front) chainring but nothing that will be enough to throw the chain (assuming you get the tension right).

Great! Thanks Brendan. I got a 15T cog, something a little easier to start with.

The smaller the rear cog makes it harder to pedal…

regarding all that rust, i use the high-tech solution of spraying everything with Ballistol or INOX, and then rubbing with with some rags. spray some inside the frame, not bucketloads though, and maybe use a bit of fine fine sandpaper inside the seatube to save scratching your new seatpost.

and yeah, when measuring stuff (cranks, frames, bolt spacing etc, the standard is from centre to centre of bolt holes, even for ‘theoretical’ dimensions like bcd/pcd)

The smaller the rear cog makes it harder to pedal…
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Woops! I knew that. I just remembered that I got the 15T to go with a 53T front sprocket.

Thanks. I’ve never heard of Ballistol or INOX. Is it any different to WD40 and can you get it in Australia?

Woops! I knew that. I just remembered that I got the 15T to go with a 53T front sprocket.
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95 GI, I hope that’s for the track…

Regarding the gear ratio, I’ve been using this:
http://www.sheldonbrown.com/gears/

But I’m unsure what wheel size to select, but I think any of the 700s should give a good indication.

I’m in Melbourne and cycle around pretty flat areas. I think I’ll try the 39/15 first. This is a gear ratio of 2.6, which equates to a gain ratio of about 5.2. Pretty easy.

I realise now the 53t sprocket is ridiculous!

High 60’s, low 70’s is a good gear ratio to start with.

Okay, I’m a little confused now! How do I calculate the gear ratio?

The search function on the forum will help you with this.

otherwise use these tables: http://n2.nabble.com/file/n4877/gearing_denny.jpg

chainring / sprocket * 27.

eg 39/15*27 = 70.9"

A good enough approximation for 700C wheels.

Thanks Blakey. Looks like the 39/15 will be a good start.

Ezy Lee, the rust looks like this:
Forks, one rubbed with foil:

Lugs

Drop outs - a fair bit of that is grease

So I think I’ll just give it a go with some wd40 and some fine steel wool (not wool, but the fairy floss stuff)

they’re all pretty similar. good hardware shops will have all three. inox is especially good for dissolving rust, and ballistol is a kind of wonder product that protects leather and plastic as well as steel. the germans invented in in WWI for cleaning rifles supposedly. anyway how good is the foil trick!

about ‘doing the chainline’, you’ll probably be ok with what you’ve got, ie: the 39t chainring on the inside of the spider.
one thing to check though is the alignment of the frame - have a look along the length of it and check that the rear triangle is symmetrical, not offset like some bikes. it looks like 10 or 12 speed era so you’ll probably be fine.