Another bout of modifications to our summer tandem, resulting in a rather mixed transmission: 11-speed Shimano cassette (reduced to 10-speed), Shimano 105 levers and rear mech, a 1990s Campagnolo tandem chainset and triple front mech, KMC chain, new Campagnolo BBs.
Some months ago, I posted about some work I’d done on our dear old Longstaff tandem. It’s about 30 years old now, and its transmission was really old school: a beautiful Campagnolo triple tandem chainset, equally lovely Campagnolo tandem hubs, and a screw on 7-speed freewheel.
Earlier this year, the old Sachs freewheel broke a cog and after a bit of searching about I bought a cheap replacement, which got us back on the road. But the freewheels available don’t seem to be particularly high quality, and I’ve had recurring issues with decent indexing on the newly installed freewheel. Most recently I found the gears only indexed in the middle of the freewheel. The upshot was that I decided to spend some cash bringing the tandem into a more modern condition.
The first step was to identify a rear wheel. Now, there aren’t many places you can buy tandem parts, and JD Tandems is one of those. I selected a 48-spoke rear wheel with a Shimano compatible freehub. Owing to my poor online reading skills (!), I mistakenly thought this was 11-speed compatible. More on that later.
However, the plan to modernise the tandem sort of grew like Topsy, as I had expected. I already had a Shimano 105 rear mech that I’d originally bought for a different project and never used.
In addition, I ordered the following (all from SigmaSports), except the two cables, which were via Amazon):
- A pair of 11-speed Shimano 105 dual control levers (mechanical)
- An 11-32 11-speed Shimano 105 cassette
- A pair of Campagnolo Centaur square taper bottom bracket sets, 115.5mm
- A tandem length gear cable
- A tandem length brake cable
- A Shimano 105 chain
I removed the tandem cranksets. This was made a little tricky since my old crank extracter doesn’t quite fit the cranks, and pushes onto the crank rather than the BB axle. I popped in a M6 bolt - its head sticks out far enough for the extracter to press on. The front BB felt pretty smooth but the rear was a bit gritty feeling. I’d worried that the original BBs would be too long at 124mm, hence I bought the two Centaur BBs.
Fitting the Centaur BBs was a bit tricky. The front went in pretty smoothly into the eccentric. The rear was a bit difficult, owing to the BB shell threads not being long enough, and the BB shell itself seemed a little short. I tightened it up as best I could, and used a spacer. Whether this is OK will become apparent, I guess. While the cranksets were off, I removed the smallest chainring.
The rear wheel seems strongly built, and with 48 spokes should last well. The hub is unbranded but looks pretty tough. When attempting to mount the 11-32 cassette I discovered that the freehub was an 8-10 speed freehub. Annoying, but not really a problem, I just dropped out the 12 cog. I really ought to read websites more carefully when ordering. Mind you, I doubt the 11 and 12 cogs will come in for much use, and there weren't many alternative wheels at the required 140mm OLN spacing...in fact I couldn't find one.
Almost modern - 11-speed cassette, reduced to 10-speed! New Shimano 105 mech
After mounting the rear wheel, I installed the rear derailleur. No issues there, though I later had to adjust the B screw. At this point, I set the upper and lower limit screws as well. I took a good look at the front derailleur, which is a 30+ year old Campagnolo MTB triple derailleur. I adjusted the two limit screws by eye as an initial setting. My plan was to try and carry on using the front mech. Time will tell if this was a wise decision.
After removing the 8-speed Campagnolo Record ergo levers and the bar tape, I fitted the two dual control levers and cabled up both brakes (Dia-Compe cantilevers) and both derailleurs.
The first Shimano dual control levers I've used in several decades - and that's my 30 year old self-built front wheel
Next up was the chain. I stopped using Shimano chains several decades ago, largely because of their annoying joining pin. On one occasion I had to get a lift back into Dundee (where I lived at the time) on a potato lorry after a shop-installed Shimano chain came apart at the join! Now that Shimano has joined the rest of the chain manufacturers in using a quick link, I thought I’d try a Shimano 105 chain. Shimano’s implementation of the ‘quick link’ concept isn’t exactly quick. It’s a whole lot harder to install the link than chains from other manufacturers, requiring a special tool that I don’t have. I did however have a KMC chain to hand, and used that instead. Simple installation that is truly quick, the link is reusable, and you can just use pedal tension on the chain to fix the link in place.
It only took a little cable adjustment to have the rear gears working smoothly. The front took a little more effort as I’m trying to persuade the mech to operate cleanly with a chainset with a shifter designed for a Shimano double front mech and a modern double chainset. But after tweaking the limit screws, it seemed OK.
Chainset with granny ring removed; plus the ancient Campagnolo triple front mech
The ancient Dia-Compe cantilevers are always a little fiddly to set up, but not too much trouble. The stiffness of the brake cable outers made it a bit difficult to hook up the front brakes, and to tape the bars. But not insurmountable.
First test ride
We went out for a short 40 minute test ride. Brakes and rear gears worked just fine. The front shifting was a bit iffy - it worked at first then decided to not work! Back home I made a few adjustments and it now seems to work, at least on the workstand.
Second test ride
For the seond test ride, we rode up to Astwood, had a rather nice lunch and then rode home. Not far, about 19 miles. The bike seemed to work fine.
This is the first bike I’ve had with Shimano STI levers. Despite this being another ‘shifting logic’ to get used to, I’m really rather impressed. The lever bodies are pretty comfortable and the shifting seems precise.
A third, and longer, test ride
Our final test ride was a 46 mile excursion into Befordshire on one of our regular routes out to a garden centre cafe. Not a single problem. No problems with any of the hills, some of which were fairly steep, with the gearing range.
In fact, the transmission works pretty much faultlessly, and a lot better than with the cheapo 7-speed freewheel on the old rear wheel.