Converting a road bike to fixie - help required

[dp2clark]

I have an old Perkins road bike that a friend is helping me to convert to a fixie. I'm buying a track crank, and have been looking at various SRAM, Campy products. I'm confused about BB though - I know there are different types - how do I know which kind I will need? Or does the crank determine the type of BB required?
I'm thinking I'll get a SRAM S-300 crankset. How much difference do the crank arms length make? As a commuter cyclist, am I going to notice any thing between a 170mm and 175mm?

Cheers.

[Recycler]

Maybe the best way to go is to get a cheap bike and start riding, Then you will know things like what different crank lengths are like. When you know what you need, then buy good gear. Happy Days.

[KGB]

Agreed, making a fixie should be cheap. Was there cranks on the Perkins already?

[dp2clark]

yeah, it has an old Shimano crank. Must be 20 years old at least though. I thought it was better to get a track crank for the thicker (stronger?) chain and better alignment?

[rustychisel]

Do some reading and research, the more.

If the Perkins is a complete bike, then all you really need to worrry about is the back wheel.

Research and decide what size gear you want to ride then source the appropriate cog. Depending on the rear hub type, yoiu might be able to use the existing rear wheel, which will need respacing and undishing.

And then all you need to worry about is removing derailleurs, cutting chain and resizing, checking chainline, and using short stack bolts for a single chainring instead of double.

If none of this makes any sense, do more research or find a friendly mechanic.

[dp2clark]

Do some reading and research, the more.

If the Perkins is a complete bike, then all you really need to worrry about is the back wheel.

Research and decide what size gear you want to ride then source the appropriate cog. Depending on the rear hub type, yoiu might be able to use the existing rear wheel, which will need respacing and undishing.

And then all you need to worry about is removing derailleurs, cutting chain and resizing, checking chainline, and using short stack bolts for a single chainring instead of double.

If none of this makes any sense, do more research or find a friendly mechanic.

Thanks for this. ^^^

The theory of it all makes sense mostly, but the practice is a different story altogether...

I've already got a pair of decent single speed wheels I bought for a cheap fixie i'm currently riding, with the view I'd put them on the Perkins later on. I want to do up the Perkins, as it is sitting in my shed at the moment, and has some sentimental value.
Ok, so I just need to get a single chainring, short stack bolts, and remove the derailleurs...I'm guessing the front brake cable could do with replacing, too.

Thanks again, hopefully I can post some pics of the finished product soon.

I'm guessing the quality of single chainrings are pretty similar???

[yugyug]

I think what rusty chisel was getting at is just use a current chain ring from the Perkins. It's a double now so separate it and to attach just one to the current crank you need to use shorter bolts.

[dp2clark]

I think what rusty chisel was getting at is just use a current chain ring from the Perkins. It's a double now so separate it and to attach just one to the current crank you need to use shorter bolts.

Ah, gotcha. Thanks...Will it be compatible with the track wheels I have on my current fixie? If not, how do I best overcome that? Cheers

[singlespeedscott]

Not unless your current one uses a 3/32 width sprocket and your front chainring has an approx 42mm chainline.

[HLC]

You can use a 1/8th chain with 3/32 width chainrings and/or sprockets, BUT you cannot use a 3/32 chain with 1/8th chainrings and/or sprockets.

So if you have a 1/8th cog on the back, and a 3/32 chainring on the front, thats OK as long as you use a 1/8th chain.

Easy.

Perkins sounds like it's awesome though. Would make a nice roadie i imagine. Throw Campy Record/DA 9000/SRAM Red on it instead

[dp2clark]

You can use a 1/8th chain with 3/32 width chainrings and/or sprockets, BUT you cannot use a 3/32 chain with 1/8th chainrings and/or sprockets.

So if you have a 1/8th cog on the back, and a 3/32 chainring on the front, thats OK as long as you use a 1/8th chain.

Easy.

Perkins sounds like it's awesome though. Would make a nice roadie i imagine. Throw Campy Record/DA 9000/SRAM Red on it instead

Simple...right

So, if I use the existing chain ring - which is a Shimano 600, according to the crank arm - and the track wheels I have bought, I can use a 1/8 chain? Are there any performance issues? Should/Can I get a track chain ring instead?

It's a really beautiful frame, but I already have a road bike, and it gets me in to enough trouble as it is!

Thanks for all the advice!

[Gordonhooker]

I have a rear wheel (WHEELSET / RIMS: WEINMANN DP-18 32H) from my 2012 Avanti Solo if you are interested. It has not done a lot of k's and is a flip/flop hub. I had a custom velosteel coastie wheel built by Dash at http://www.coasties.com" onclick="window.open(this.href);return false; for my bike and the original is sitting around gathering dust.

I am in Brisbane let me know if you are interested...

[dp2clark]

I have a rear wheel (WHEELSET / RIMS: WEINMANN DP-18 32H) from my 2012 Avanti Solo if you are interested. It has not done a lot of k's and is a flip/flop hub. I had a custom velosteel coastie wheel built by Dash at http://www.coasties.com" onclick="window.open(this.href);return false; for my bike and the original is sitting around gathering dust.

I am in Brisbane let me know if you are interested...

Thanks, but I have a couple of spare rear wheels already.

[Gordonhooker]

No worries it was there if you needed it.

[dp2clark]

No worries it was there if you needed it.

Cheers - nice looking wheels those coasties!

[KGB]

No real performance issues with the chain and ring combo. You could get a track ring but would need it to be 130 bcd, I'm sure they exist but most track rings are 144 bcd.

[HLC]

You can use a 1/8th chain with 3/32 width chainrings and/or sprockets, BUT you cannot use a 3/32 chain with 1/8th chainrings and/or sprockets.

So if you have a 1/8th cog on the back, and a 3/32 chainring on the front, thats OK as long as you use a 1/8th chain.

Easy.

Perkins sounds like it's awesome though. Would make a nice roadie i imagine. Throw Campy Record/DA 9000/SRAM Red on it instead

Simple...right

So, if I use the existing chain ring - which is a Shimano 600, according to the crank arm - and the track wheels I have bought, I can use a 1/8 chain? Are there any performance issues? Should/Can I get a track chain ring instead?

It's a really beautiful frame, but I already have a road bike, and it gets me in to enough trouble as it is!

Thanks for all the advice!

Yep that's it.

Lets see the pics now.

[dp2clark]

https://twitter.com/_danclark/status/525482810375553024" onclick="window.open(this.href);return false;

Having a bit of trouble posting pic, but here's a twitter link. If there's anything else I need to consider, but haven't, please point me in the right direction. The last thing I was thinking was brakes. I only have a front brake currently, and am comfortable with that. Should I invest in a new brake/levers, or will the existing be sufficient?

Cheers

[dp2clark]

Front brake on the bike I'm riding now, I mean.

[KGB]

I ride single (not fixed) with front brake only.

[jaseyjase]

If you're riding single speed its best to have front and rear brakes just in case one of the cables snaps unexpectedly

If you're riding fixed its ok to have just the front as you still have your legs to slow you down

Thats the general rule of thumb

[Derny Driver]

if you are using the 600 road cranks with a road chainring (3/32) then you buy a 3/32 cog and run a normal road chain. Instead of buying short chainring bolts you can cut the lugs off an old chainring and put them where the small chainring used to be and use the bolts you have.

If you buy new cranks then buy 144BCD track cranks so that you can run a standard track chainring and a standard 1/8 cog with a track /BMX chain.

The bottom bracket is determined by the shell it sits in. Best to leave it as is and just switch cranks or use the 600 cranks. BB should be square taper which means most cranks will fit although there are some different sizes of square tapers so you would need to 'try before you buy' to make sure the new cranks fit on the old BB correctly.

Personally Id leave the BB and cranks as is, and buy a 3/32 cog. Check gear charts for the correct cog size to chainring ratio.

[dp2clark]

Yeah, I'd like to keep things as simple as possible, for my own sake. I think I'll keep the 600 on, with the original chain ring, and the wheels I'm currently using (which I'm guessing are the 1/8 cog as they're track wheels). I'll also use a 1/8 chain, as suggested by HLC. I've been riding fixed for a month or so now, and after the typical rookie mistakes, haven't looked back.
Will post as I go, and no doubt ask a lot more questions along the way! Cheers!

[dp2clark]

One last thing, in regards to brake levers. I was thinking of replacing the brake levers w/ some flat bar road brakes, and I've notic d different measurements. What does this measurements refer to, and how do I know what size I require???

[dp2clark]

This is a shot of the handlebars. According to Shelton brown, thsee colnago bars would be 23.8mm, as I'm assuming they're pre 1998?

http://sheldonbrown.com/cribsheet-handlebars.html" onclick="window.open(this.href);return false;

Again, I can't seem to post photos, so here's a Twitter link...

https://twitter.com/_danclark/status/527068044133019649" onclick="window.open(this.href);return false;