JakcBeNimble

I've been spending a fair amount of time at my parents house lately, and I noticed that my dad has suddenly started riding an old 10 speed Torpado that's been hanging in the garage for the last 20 years.

He's probably the hardest person I know to shop for, and so I thought that upgrading his beat up old bike would be a nice gift. Obviously I'll take care of the obvious stuff that needs attention like oiling the chain, checking tires and tubes, replacing brake pads if need be, and greasing all the moving parts if they need it.

The questions I have revolve around the shifters and freewheel. My eventual goal is to have a 7s freewheel, with a Shimano 7s RSX shifter/lever on the right side, and a standard aero lever for the left, while leaving the downtube shifter for the front derailleur.

I have the shifter already (spare parts), but not the matching brake lever for the other side, and I don't have a freewheel yet. I also have housing stops that can be mounted on the downtube (with some modification to fit the clamp-on DT shifter mount). I can easily get cables and housing as needed.


Questions:

1. Will a 7s freewheel fit the mount of the 5s freewheel and fit inside the frame without redishing the rear wheel?

2. Will modern (or close to modern) brake lever work with the old Universal Mod. 61 center-pull caliper brakes and have an acceptable pull ratio?

3. a. Will the old chain still work or do I need to get a new one to accommodate the 7s gears?
b. IF I need a new chain, will it likely work with the existing chainrings?

4. Will the rear derailleur be compatible with the shifters (does it have the right shift ratio)? Its a Suntour V-GT Luxe. There's a great used parts shop near me so finding a replacement shouldn't be a problem if needed.

5. Any recommendations on a matching aero brake lever for the side opposite the brifter? Ideally it should have the same feel as the brifter and the same reach.


Finally, know this isn't really worth the effort, but it'll be a fun project that uses up some of my spare parts while using my dad's old bike, so its worth it to me. Thank you for any advice, and don't hesitate to ask clarifying questions where I forgot to include some information.

tatfiend 

1. Most 5 speed frames were 120mm dropouts while wide 6 speed and 7 speed hubs were 126mm. Measure the dropout width. You might need to cold set the frame and lace a new wheel or fit a new axle and spacers, plus redish the wheel, for 7 speeds.

2. Will work so far as I know.

3. The old chain may or may not work. Width should be ok but chains went through design changes to give better shifting as part of the development of indexed shifting. So did freewheel tooth designs. A 7 speed Shimano Hyperglide freewheel would be my choice.

4. The Suntour rear derailleur will most likely not work with the RSX shifter. Per Frank Berto's 1988 book on upgrading bikes Shimano and Suntour rear derailleurs had different cable pull requirements. Both Shimano and Suntour made design changes to their rear derailleurs as part of introducing indexed shifting. Older rear derailleurs from both companies were not considered indexed shifting compatible.

5. No idea. Going to look a little odd with 1 brifter and one non brifter.

If the bike sat for 15+ years relube everything such as headset, bottom bracket and wheel hubs. Also replace the brake pads as they harden with age.

Indexed shifting was considered a package deal and both Shimano and Suntour redesigned most drivetrain related components to build successful indexed shifting systems. Indexed shifting eliminated much of the ability for bike gearheads to mix and match components from different manufacturers that used to be possible with friction shifting derailleur systems.

JakcBeNimble

Wow, I wasn't expecting such a detailed and informative reply so quickly. Thanks for the information.

The dropout spacing is a little disconcerting. I didn't realize that 5s spacing was different from 6s and 7s spacing. This might complicate the whole project too much to make it worth it now. The only reasonable solution that I can come up with right now is to get a new rear wheel with 126mm spacing and add a 7s freewheel (Hyperglide would be ideal), and then coldset the frame and pray it stays straight.

Most of the rest of the answers confirm what I already knew, including how odd its going to look with one brifter and one non.

bikemeister

Didn't someone make a "compact 6" freewheel that could upgrade a 5-speed without coldsetting the spacing? I seem to remember something like that. They had true 6 and 7-speed freewheels for the newer models of 126 spacing, but I thought you could upgrade a 5-speed you were in love with with one of these compact 6's.
EDIT: Found it on sheldons site - it's called an Ultra Six. Had narrower spacing between gears so 6 would fit in a 5-speed dropout. Don't know if all that trouble is worth only one more speed, FWIW

JakcBeNimble

Yeah the Ultra Six mod wouldn't really be worth it. A main reason I'd like to do this is to use parts I already have.

tatfiend 

Frank Berto claimed that the Ultra 6 freewheels shifted poorly compared to wide spaced 6 speed freewheels with the chains and derailleurs of the era. For info on upgrading older bikes Berto's book from 1988 on upgrading bikes is still useful. IIRC the title is "Bicycling Magazine's Complete Guide to Upgrading Your Bike" by Frank Berto. Lots of info on freewheels and derailleurs of the era including a lot on early indexed shifting parts. Used copies are available on Amazon the last I checked.