Posts Tagged ‘KMC’

It’s the little things

August 23, 2021

Running a tab (that little black gizmo between the derailleur and its hanger).

For a while I’ve been considering various ways to make my single-ring Voodoo Wazoo a little less gravity-challenged.

The bike has been through some changes over the years, but it eventually settled down as a flat-bar, single-ring, 7-speed trail bike with 700×42 rubber.

One thing it’s kept throughout its various incarnations is some old-school-cyclocross gearing. The ancient Shimano 600 crank can handle a 38T inner ring, and the Shimano 105 rear derailleur a 12-28T cassette. This yields a low end just short of 38 gear inches, which is a tall order in some neighborhoods.

So I wanted to change it on the cheap. But how? Especially during The Great Parts Drought.

The only derailleurs in the parts bin are Shimano road, so no joy there. And I’m fresh out of square-taper 110×74 BCD cranksets, or I could pull four teeth out of my chainring like a crazy dentist. But then I wouldn’t have a guard to replace the outer ring. O buggah.

Rivendell has this nice Clipper double that would be just the ticket. Reasonably priced, but still a few bucks past “on the cheap,” and anyway it’s out of stock. Plus I like the simplicity of my single-ring setup.

But while I was nosing around over there I stumbled across this $10 doodad, a SunRace SP570 extender link to put a bit more daylight between that old derailleur and its hanger.

Now, the wiseguys have been using items like this for a good long while to retrofit wide-range cassettes to older bikes. The boyos at Wolf Tooth make a couple of them, the RoadLink and and GoatLink. Being an indifferent mechanic, I went with Riv’s bargain SunRace model to mitigate my shame should I achieve failure, as is often the case. Bought a nice KMC X8 chain while I was there, and then noodled on over to Soma Fabrications for a 7-speed S-Ride cassette (11-34T).

The SunRace link included exactly zero instructions, but installation seemed as straightforward as it gets. Replace old cassette with new; remove old chain and derailleur; attach link to hanger and derailleur to link; and finally size, cut, thread, and close chain.

Well, hell. A bit of fine-tuning with the limit screws and I was off and rolling. I believe I could’ve gotten a 36T to work with this rig, but I’ll settle for 34. Sixty bucks equals 30 gear inches, more or less. If you’re looking for an easier ride on an old beater, the SunRace SP570 is a cheap ticket.