1970’s road bike frame query

Norwood42

Dirt Disciple
Hi, I have my dad’s old 1970’s road bike that I’d like to do up. I’m wondering if I could put my Mavic Cosmic Elite wheels on it if I get a 6 speed rear cassette fitted so that the wheel fits the rear forks spacing as currently it’s 9 speed cassette on a road bike with 130mm rear spacing. If I can do this with a smaller rear cassette wil the chain line up with the original 2 cog front chainset or will it be out of line and a nightmare? Could I also replace the front cogs for more modern ones? Bike has all the original derailleur/brakes etc. It’s just the Mavic wheels I’d like to stick on it if possible. Any help much appreciated!
 
Let's focus on the wheels first: I want to make sure I understand your goals and components.
The Mavic rear wheel is currently 9 speeds and in a bike with 130mm O.L.D. (Measurement between the dropouts)?
You want to fit a 6 speed cassette onto your Mavic rear wheel to put into your dad's older bike?

Assuming these statements are true, you're going to have some issues.

Most bikes from that era are going to have a 126mm O.L.D. for the rear wheel. If your Mavic wheel is 130mm - which is not due to the cassette but the hub itself - it will not fit in the bike without either "cold-stretching" (Which is permanently deforming the metal) or bending the arms outward slightly as you put the wheel in. That's not a huge deal and is fairly common in retrofitting new wheels on older frames - steel can bend slightly and 4mms requires very little bending.

You won't be able to put a 6 speed cassette on the wheel, though. The way the sprocket clusters worked at 6 speeds and work now at 9 are different - 6 speed clusters use freewheels and 9 speeds use cassettes. You may be able to put a 7 speed cassette on the Mavic with cassette spacers but that has its own problems and troubleshooting.

Retrofitting bikes with new parts is doable and is how I started learning about bikes myself. It will teach you a lot about the different standards of bikes and bicycle parts... because you'll be fighting against them to get your bike to function! It's hard to predict what all needs to be done to get new parts on an old bike as changing one component will lead to issues elsewhere.
 
Within limits you'll be able to change the front rings but not by much going down. Depends on the chainset. What is it? A 130BCD Shimano chainset can only go down to a 38T smaller chainring. If its Campagnolo and 144BCD then 42T is your smallest. (41T is possible but they are like unicorns). If you want to lower your gearing you are best concentrating on your rear gears.

I think the 6sp on that mavic wheel is a non starter.

Agree with @Guinessisgoodforyou - if you want 70s get some wheels with a 126mm spaced rear and a thread on freewheel - or a later (80s) wheelset with a 6sp freehub and cassette. Or you can still buy threaded, large flange retro looking hubs with sealed bearings - take them to your local wheelbuilder and get something tight and new built up for same kind of money as good used wheels.

 
Last edited:
Within limits you'll be able to change the front rings but not by much going down. Depends on the chainset. What is it? A 130BCD Shimano chainset can only go down to a 38T smaller chainring. If its Campagnolo and 144BCD then 42T is your smallest. (41T is possible but they are like unicorns). If you want to lower your gearing you are best concentrating on your rear gears.

I think the 6sp on that mavic wheel is a non starter.

Agree with @Guinessisgoodforyou - if you want 70s get some wheels with a 126mm spaced rear and a thread on freewheel - or a later (80s) wheelset with a 6sp freehub and cassette. Or you can still buy threaded, large flange retro looking hubs with sealed bearings - take them to your local wheelbuilder and get something tight and new built up for same kind of money as good used wheels.

Nice hubs and sealed bearings, good find 👍
You need to consider wheel size. Are they 27" or 700c?
 
Within limits you'll be able to change the front rings but not by much going down. Depends on the chainset. What is it? A 130BCD Shimano chainset can only go down to a 38T smaller chainring. If its Campagnolo and 144BCD then 42T is your smallest. (41T is possible but they are like unicorns). If you want to lower your gearing you are best concentrating on your rear gears.

I think the 6sp on that mavic wheel is a non starter.

Agree with @Guinessisgoodforyou - if you want 70s get some wheels with a 126mm spaced rear and a thread on freewheel - or a later (80s) wheelset with a 6sp freehub and cassette. Or you can still buy threaded, large flange retro looking hubs with sealed bearings - take them to your local wheelbuilder and get something tight and new built up for same kind of money as good used wheels.

Thanks for your reply and yes as you guys have said I think I’ll have to go with some old school wheels. Really sorry I’m a bit of a novice here but do you think I’ll be able to get some lightweight pretty decent/quick wheels with the 126 spaced rear or will it be mostly heavy steel wheels possible?
 
Back
Top