Conversion form a 7 speed to 10 speed and a bit more complicated

Hello everyone,

I followed this place for quite some time since,some good week ago, I got the idea of adding a 2nd set of wheels for my Croix de Fer 20 2016.

As I got to the conclusion that I cannot properly fit a 650b x 47 WTB tire to take the bike on tours slightly off-road I found my self a project.

I have a FreeSpirit FS26STi steel frame and got the idea to make this bike as kind of my off-road bike to see if I like it or not. Researching about it I could not find much about it and as much as I understood FreeSpirits where some cheap bikes at their time.

So I like the frame 1st of all. I also liked to use most of its components Shimano 100GS until I discovered that the front shifter is not working. The wheel are really battered so I will have to rebuild those, but to my surprise I discovered that the rear one is free-hub 7 speed.

As the lowest speed ratio is 1:1(28t-28t) this free-hub opened new opportunities. But about that a bit later, depending on the answer to my question.

I have the old rear hub of the CdF and thinking to convert the bike to 10 speed(implying to buy the appropriate shifters). The new hub fits reasonably well in the frame(this tested without the wheel). Actualy I just have to push it slightly as I think the axel of the 10 speed hub is maxim 5mm larger.

I also plan to use the 100gs rear derailleur as the project has to be very cheap and I will rebuild the wheels(at east I will try) with the better shaped rims from other bikes.

My question is this: Is there anything that I am missing? Would the 10 speed cogs work with the 7 speed Shimano 100GS derailleur?(hand pushing the derailleur it seems that it reaches the furthest part of the free hub). Is there anything that I might need to be aware of?

Forgive the long text!

Check if the chain can shift to the smaller sprocket. Some times in old frames the drive side seat stay is not flattened where it meets the dropout. With 7 or 8 speed is fine as smaller sprocket is not that close to the dropout but when you install a cassette with more gears, this can be an issue.

Thanks!

As for the shifters. The front one should be 3x7 to work with the 100GS crank set or a 3x10 would work too.(i.e: deore m610)?