Parts compatibility?

[sabian92]

Hey all,

I just wondered - what's the main things to look out for when choosing new parts? I'm looking at building up a frame, but I wanted to add a 9 speed cassette to it even though it originally had a 7 speed freewheel (I believe) on it, with a triple at the front - would that pose a problem?

I was also hoping to change the shifters from grips to thumb operated (it's a flat bar) or to STIs (and going to drops).
I know next to nothing about building bikes so any general tips are appreciated, Cheers.

 

[RecordAceFromNew]

The answer would look like a book if one is to answer your question properly, but fortunately, the late great Sheldon covered pretty much most of the points somewhere on his site. I would suggest you start from this page.

I would also suggest you think through carefully exactly what sort of bike you want and what features are important to you before your start, and to avoid disappointment post the frame spec and parts list here before committing. Component costs and weights might also be useful information for planning, if they matter to you.

 

[sabian92]

Weight isn't important to me as long as it doesn't make it feel like i'm riding a tank. I essentially want a commuter/beater bike - I was looking at doing the Trans Pennine next year and my road bike won't do it, so I want some fatter tyres, but they won't fit on my road bike.

 

[PpPete]

First ... it's not going to be as cheap as you imagine. You are probably going to need a new rear wheel hub as well as all the gear gubbins.
Second ... what's your rear drop-out measure (like this) If anything other than 130 mm or 135 mm then
if the frame is anything other than steel.... STOP ! Right Now!

 

[sabian92]

I'll measure it when I get home - I do think it's 135mm though as it's a 7 speed hybrid frame. What's the problem if it's not steel?

 

[RecordAceFromNew]

First ... it's not going to be as cheap as you imagine.

+1. Building a bike from new parts is likely the most expensive way to own a bike, even if labour is free. It is only worthwhile for fun, educational or special requirement purpose etc.

 

[RecordAceFromNew]

I'll measure it when I get home - I do think it's 135mm though as it's a 7 speed hybrid frame. What's the problem if it's not steel?

Can't cold set (i.e. permanently bend) alloy frame to accommodate wider hub, even steel it has to be non-exotic (no higher than e.g. 531) without causing permanent damage.

 

[PpPete]

What's the problem if it's not steel?

You can change that spacing on a steel frame - you can't on any other material.

Edit - RAFN beat me to it !

 

[sabian92]

Ah ok, fair enough then!

I need new wheels anyway - I know it's not a cheap way to get a bike but it's worth it to me simply because i'm interested in learning how they work and fit together.