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Sunday, May 19, 2024

Truth Or Friction? – Bike Snob NYC


The extra I experience the Cervino, the extra I need to preserve driving it:

In case you missed it, the Cervino is ostensibly a Nishiki, however it’s in reality hiding a small Viner between its stays:

Sorry.

I’m additionally sorry for the next picture:

You possibly can kind of really feel summer time zipping up and preparing for the descent into fall, however within the meantime it’s nonetheless sizzling and I’m getting good use out of the Pearl Izumi Assault Air Jersey and Assault Air Bib Quick. The jersey particularly is gentle and cozy, and the aggressive title however the ensemble has an understated look that goes properly with a basic bike–although I nonetheless want to handle my shoe state of affairs (or “shoe-tuation”):

Relaxation assured I’ve already taken a number of necessary “steps” (see what I did there?) in direction of doing so.

Talking of steps, I’ve additionally taken an important one in getting ready for the Basic Cycle twenty first Century Friction Shifter Shoot-Out:

This concerned mounting the primary check derailleur onto the official check bicycle (or “test-cycle”):

I figured I’d go in more-or-less chronological order beginning with what I’m assuming is the oldest derailleur, the Shimano Altus LT, which so far as I can inform dates again to the late Seventies and early Nineteen Eighties:

Listed here are the specs, by way of the Disraeligears web site:

When this derailleur was present I used to be driving round on a Schwinn Scrambler with a coaster brake so I don’t know what its supposed use was, although it’s in all probability secure to say it was “geared” (that’s one other pun!) extra in direction of so-called “informal” riders than racers. I used to be additionally too busy driving off curbs to be measuring rear spacing and counting cogs, however I’m assuming it will mostly have been discovered on bikes with 5- or 6-speed freewheels and rear spacing of 120mm to 126mm–and if I’m mistaken I’ve a sense you gained’t be shy about correcting me.

In any case, right here we’re over 40 years later. Will the Altus LT work on a motorbike with a motorbike with 130mm spacing, a 34/50 compact crank, and a 13-29 Campagnolo 10-speed cassette? Right here’s the test-cycle as I’ve been driving it, with a brief cage 10-speed Shimano 105 5700 rear derailleur. That is the 5700 on the biggest cog and smallest chainring:

And right here it’s on the biggest cog and the biggest chainring:

Right here’s the corresponding shift lever place:

And right here’s the burden of the 5700 derailleur:

Weight weenies ought to be aware these will not be the unique pulleys, although I can’t think about that might meaningfully have an effect on the general weight. Then once more, once you’re a weight weenie any measurable distinction is significant.

Set up of the Altus LT derailleur went as easily as one might moderately anticipate given my lack of competence. All through the check I’ll do my finest to not change something which may introduce bias into the general outcomes, so for that motive I saved the chain filthy. (That stated, the check would require me to open and shut the chain at the least seven occasions, so I do reserve the proper to vary the fast hyperlink if I start to query its integrity.) Right here it’s on the massive cog and the small chainring:

And right here it’s on the massive cog and enormous chainring:

As you’ll be able to see, its capability appears enough. Its vary can be greater than enough to cowl all the cassette, and when in low gear there seems to be loads of clearance between the pulley cage and the spokes. (This can be a drawback I’ve had earlier than when utilizing previous derailleurs with newer, wider cassettes.) And right here’s the place of the shift lever when in low gear:

The lengthy throw required for the 5700 isn’t in any respect an issue in apply, however I’d nonetheless file this underneath “enchancment.” I also needs to be aware that the place of the restrict screws in addition to the truth that you’ll be able to look proper into the parallelogram and see the place they’re protruding makes adjustment simpler than it’s on newer derailleurs just like the 5700 (not prefer it’s significantly troublesome, however nonetheless), although that is considerably mitigated by the truth that the anchor bolt is a hex bolt and never an Allen bolt. And sure, the Altus AT is a whopping 28 grams heavier:

However that’s solely in regards to the weight of a single fancy crabon water bottle cage, and since I don’t have any fancy crabon water bottle cages on the bike I believe I can spare the grams.

Okay, so this 40 year-old relic weighs solely barely greater than a 10-speed 105 derailleur, has the identical vary and capability, and is less complicated to regulate. How have derailleurs really improved? Effectively, as a few of you have got famous, the newer derailleurs on this check have a “slant parallelogram” design, as you’ll be able to see right here:

The older ones, together with the Altus LT, don’t:

So for causes we’ll conveniently not trouble with, the newer derailleurs ought to work higher. However there’s additionally different stuff that makes fashionable bikes shift higher too, like ramped cogs and improved chain design, so we’ll see how a lot of a distinction a slant parallelogram makes on a motorbike that already has all that different stuff.

However there may be one function the Altus LT has that newer Shimano derailleurs don’t, and that’s a “Centeron Mechanism.” Right here’s what that’s, in accordance with up to date Shimano paperwork by way of (the place else?) the Disraeligears web site:

Within the pre-SIS, pre-Hyperglide days, this was Shimano’s try and make shifting smoother and simpler. Right here’s the precise mechanism, which you’ll see doing its factor once you shift, and even once you tighten the anchor bolt:

After all I gained’t be utilizing it with the Centeron shifters for which it was designed, and never having really ridden the bike but I don’t know how or even when it’s going to work in apply or what impact it’s going to have. It was additionally current within the first iteration of XT (and I’ll after all be testing a kind of, too) however the mechanism was gone by the point SIS (that’s indexing) got here in–although as I perceive it the underlying idea lives on in Shimano’s floating pulley, which I imagine are (or at the least have been) additionally referred to as Centeron. In any case, if nothing else it’s noteworthy as one among Shimano’s final massive makes an attempt at shifting refinement earlier than the SIS/Hyperglide period.

Anyway, every part checks out pre-flight, so I’ll let you know the way it does out on the highway.

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