Bernard sent in the following question:
“I have a steel touring bike from 1984. I love the bike because of the all-day comfort these old frames offer, but the 6-speed freewheel/Suntour XC “elliptical” chainrings and prototype index/friction downtube shifters combination don’t work that well, as it tends to want to slip out of gear. Is it a practical alternative to swap in a modern indexed shifting system?”
The bike in question — on tour in France:
Good news, Bernard…this is an entirely feasible process. Luckily, just about anything is possible in converting an old bike into something more modern — there are quite a few companies out there who make specialized adapters and such to resurrect an old friend and to teach him new tricks!
To set up modern indexing shift systems on an older bike, there are a couple things to consider: dropout spacing and how many speeds you want in the finished bike (deciding now can really simplify the conversion process, as we will see).
After speaking with Bernard, I learned that he is willing to do the full upgrade — shifters, new rear wheel, derailleurs and new chainrings. The chainring part is easy. Merely swap the old Suntour OvalTech chainrings for modern 8- or 9-speed specific rings…no crank replacement required!
Dropout spacing is really the only tricky consideration. On one- through 5-speed bikes, the rear dropout spacing was typically 120mm. With six speed systems and early “ultra 7″ systems, the dropout spacing jumped up to 126mm. Modern 9- and 10-speed drivetrains have 130mm spacing. Since Bernard indicated that he currently has a 6-speed freewheel, the frame’s spacing need to be pushed out an additional 4mm. I’ve covered doing this in another article, but if you’re not comfortable doing it yourself, any competent bike shop should be able to help. Again, luck is on Bernard’s side, as the frame in question is steel. Don’t try this on an aluminum or carbon frame!
The only specialized equipment needed to modernize the shifting system on this bike (aside from the new components themselves) are downtube-mounted cable stops such as these:
These cable stops simply bolt to the downtube shifter bosses and provide the anchor (and adjustment) for the shifter cables. If you don’t have brazed-on shifter bosses, there are band-on models available as well.
I won’t go step-by-step into the conversion itself, but after the rear dropouts are spaced correctly, simply bolt on the new components, slip the new wheel in, string your shifter cables and adjust everything so it shifts cleanly.
Here’s a handy trick if you’re strapped for cash or don’t want to do the full-tilt conversion…and the reason I suggested deciding on the number of gears needed before you run headlong into this conversion project: if you have a seven-speed freewheel (Shimano still makes Hyperglide-compatible 6 and 7 speed freewheels in limited quantities!), you can make it work as a modern indexed system with 8-speed indexed shifters (readily available on the secondhand market, such as Ebay). No new rear wheel or rear derailleur required! You’ll just have an extra “ghost click” on the shifter. The only kink is that sometimes there’s not quite enough clearance between chainstay and smallest cog, but that is easily rectified by slipping a couple spacers under the drive-side hub locknut (2 or 3mm is all it takes). Sometimes simple is best…
Finally, the last consideration is not to mix brands. There are adapters to make Shimano components play nice with Campagnolo or SRAM, but it’s better to “keep things in the family” for precision’s sake.
It is really fun and rewarding to breathe new life into an old friend — you CAN teach an old dog new tricks with a little tinkering. Bernard, be sure to tell us how it all works out, and happy riding!
Have a cycling-related question? Just Ask Jack! Click on the link in the right-hand column to send me your questions.
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10 responses so far ↓
1 Just Ask Jack — Modern Shifting on a Classic Bike? // Mar 11, 2008 at 9:21 pm
[...] Buckeye Commentary | An Ohio State Sports Blog wrote an interesting post today onHere’s a quick excerpt Bernard sent in the following question: “I have a steel touring bike from 1984. I love the bike because of the all-day comfort these old frames offer, but the 6-speed freewheel/Suntour XC “ellipticalâ€? chainrings and prototype index/friction downtube shifters combination don’t work that well, as it tends to want to slip out of gear. Is it a practical alternative to swap in a modern indexed shifting system?â€? The bike in question — on tour in France: Good news, Bernard…this is an entirely fe [...]
2 Justin // Mar 11, 2008 at 10:30 pm
It’s pretty easy, Shimano actually still sells downtube and barcons, although they run about 80-90 bucks. The barcons come with the downtube stops you mentioned, if you’re interested in keeping the older look but with a newer, indexed feel. All these are available from Rivendell (www.rivbike.com).
3 Mike Myers // Mar 12, 2008 at 3:02 am
I’m thinking barcons would the the way to go, as well. They are easy to find because triathletes use them on their aero bars. So what does he need? New rear wheel, cassette, barcons, and a rear derailleur, right? Should be easy to spread the rear triangle.
4 cafn8 // Mar 12, 2008 at 3:51 am
I’ve recently started riding a 1980- something 12-speed Panasonic for my commute. There is still plenty of action left in its gears, but just to familiarize myself with the bike I was measuring the rear frame spacing. I measured around 123mm. When the wheel is inserted, the dropouts must be spread slightly. My first thought was that it was manufactured this way in order to accomodate either 5 or 6 speed hubs. Was this a common practice? I guess the other option is that the frame is misaligned, which wouldn’t be unheard of on a bike that’s been shuffled around in someone’s garage for 20 years. It is a steel frame, though, so it’s probably not a big issue either way.
5 Ghost Rider // Mar 12, 2008 at 4:16 am
cafn8, the rear spacing was often not exact, like the Panasonic you describe — the dropouts were expected to be sprung out a bit to insert the wheel. Certainly, the frame could be misaligned or slightly bent in some other way…
An alternative is “time set” — for example, I’ve got an old Bianchi with an original spacing of 120mm. It came with a 5 speed freewheel, but many years ago I upgraded to a 6 and shoehorned it into the frame by spreading the dropouts with my hands. Now, after so many years of being spread around a 126mm O.L.D. hub, the dropout spacing measures 124 with no wheel in.
6 Bicycle Tutor // Mar 13, 2008 at 2:37 pm
A lot of people are going to benefit from this article as it is such a common request. Thanks Jack!
7 Twodeadpoets // Mar 13, 2008 at 10:02 pm
I have an old 1970s Olmo that has upgraded Campy Records on it. I also used the cable stops featured in the article.
Picture of my Olmo (http://tinyurl.com/ynp8hd)
8 Joe // Apr 20, 2008 at 8:31 am
I updated a 1984 Trek 720 tour bike to a modern Nexus 8 speed internal geared hub. Works great. This bike is now my primary commuter.
9 Eddie // Jul 19, 2008 at 8:52 am
Hi,
I have done such a upgrade on a 1980 bike (Gazelle ‘champion mondial’). I have kept the original 6-speed wheel (126 mm OLT, although a 130 mm fits perfectly) on which I have screwed a new Shimano HG22 14-24 6-speed hyperglide freewheel.
I have replaced the old Campa nuevo record rear derailleur by a cheap Shimano Sora.
I have installed (2nd hand) Campagnolo Ergopower 9-speed (pre 2001) shifters.
I had to buy a pair of cable-stoppers and a Campa cable set.
Installation was rather simple as Campa “old” 9-speed pulls just enough cable to shift the Shimano Sora 5.5 mm as required for the 6-speed. The front derailler and chainwheels (both Campa nuevo record) were kept. I also installed a new 8-speed chain (SRAM PC-58).
In principle, the Campa Ergopower can deal with almost all kind og front deraillers as it has several “clicks” to allow fine tuning
10 Ghost Rider // Jul 19, 2008 at 11:29 am
Eddie, does the Ergopower rear shifter work to “index” the derailleur over the six-speed freewheel? If so, WOW — there’s so much out there that can be made to work — old and new coexisting beautifully!
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