Conversating 6-speed freewheel to 10-speed cassette

[Kay]

I have an older steel road bike — I'm guessing late 1970s, early 1980s, but a high-quality Columbus tubing steel frame. It has old Mavic wheels w/ freewheel, 6-speed, but I am wondering if it is possible to convert the bike to a more modern cassette. I have an old Easton 10-speed wheel, and I am wondering if that would fit the frame (or how I can find out if it will).

My second question is this: assuming the conversion is possible, I know I would need new downtube shifters (10 speed) as well as a new chain, and probably a new rear derailleur. Are there other things I would need to change, as well?

Thanks so much in advance.

[ReapThaWhirlwind]

It's possible, but considering that your bike probably has an integrated rear derailleur hanger, you might have issues there.

Everything else should fit, but I did this same conversion for a GT Outpost Trail, and the newer Shimano ZEE RD could not shift down into the lowest cog because the frame geometery. It was simply too bulky. I had to switch to an older Shimano Ultegra RD to get the clearance I needed.

I recently saw they have rear derailleur hanger extensions available now. They just bolt-on to let your bolt-on RD hang lower.

You might be able to get one of those to troubleshoot further.

[Criminal]

(03-05-2022, 06:31 PM)Kay Wrote:  I have an older steel road bike — I'm guessing late 1970s, early 1980s, but a high-quality Columbus tubing steel frame. It has old Mavic wheels w/ freewheel, 6-speed, but I am wondering if it is possible to convert the bike to a more modern cassette. I have an old Easton 10-speed wheel, and I am wondering if that would fit the frame (or how I can find out if it will).

My second question is this: assuming the conversion is possible, I know I would need new downtube shifters (10 speed) as well as a new chain, and probably a new rear derailleur. Are there other things I would need to change, as well?

Thanks so much in advance.

To fit the 10 speed hub you would probably need to change the rear fork spacing. Your inner dimension between rear drop-outs is most likely 120mm - 126mm. The O.L.D. (Over Locknut Dimension) of a 10 speed compatible road hub is about 130mm. Going from 120mm to 130mm is a fair stretch of the frame and causes the drop-outs to become misaligned. Going from 126mm to 130mm isn't to bad, but it still causes some degree of misalignment of the rear fork although you may not need to alter the rear fork unless you prefer to easily install the new wheel without having to manually spring apart the rear fork every time you put the wheel in. To properly install a wider hub you will need to bend the frame apart and then re-align the drop-outs. It is technically called "cold-setting" a frame. I tend not to do it for many reasons, but it can be done safely without causing damage.
Finding components to convert should be no problem, but you need to ensure they will function for your expected use on that frame with the gearing you plan to install. Shifters, derailleur, cassette, and frame need to become compatible. Easy to do a friction shift over an index shift because of less issues with cross compatibilty of different component brands/models. Best to talk to bike shop professionals and see what their recommendations are.


Here is a link to a thread addressing this process:
https://forums.bikeride.com/thread-7834.html?highlight=Cold+st

Within that thread there is a link to a website that goes into detail what it entails to cold-set a frame yourself. You can also just do an online search for the process and you'll find videos on it. Good bike shops will do it, but ensure they have experience first in cold-setting a frame.

[Jesper]

(03-05-2022, 06:31 PM)Kay Wrote:  I have an older steel road bike — I'm guessing late 1970s, early 1980s, but a high-quality Columbus tubing steel frame. It has old Mavic wheels w/ freewheel, 6-speed, but I am wondering if it is possible to convert the bike to a more modern cassette. I have an old Easton 10-speed wheel, and I am wondering if that would fit the frame (or how I can find out if it will).

My second question is this: assuming the conversion is possible, I know I would need new downtube shifters (10 speed) as well as a new chain, and probably a new rear derailleur. Are there other things I would need to change, as well?

Thanks so much in advance.

What has been previously said is good advice; but you'll also need a narrow chain for that cassette. You may also have to change the length of your bottom bracket spindle depending on where you want your chainline to be, and/or you may have to dish the rear wheel in or out in order to center into the rear fork. Too many people think that just cold setting the frame to fit the new hub/wheel is all you need to do. If you want to avoid too much extra work or parts change out, try to only go up or down one size (e.g. 120 to 126mm, or 126mm to 130mm) as it can often allow you to just manually spring the rear fork apart and often everything still aligns fairly well. It's always a little hit or miss depending on exactly what you are doing. You will usually know once you start to ride how everything gelled; especially the alignment. Try riding no hands and see where the bike wants to go (that is assuming the front end alignment is proper and headset is set up correctly).