ElliotSF

If, at the risk of blasphemy, you were to buy a contemporary long-cage rear derailleur for a forthcoming project, would a Shimano Deore (M591 SGS) be a good choice? I ask because while I love my vintage Suntour derailleurs (VGT Luxe, VX, Sprint, Cyclone), I sometimes wonder if I'm missing anything. Am I? (I've read here that "modern derailleurs work better," but I don't know what that means, exactly. By the way: I'm perfectly happy to run in friction mode.)

fender1

I have used all manner of vintage long cage deraileurs (Campy, Suntour, Shimano) but they all don't perform as well as a modern Shimano long cage. I have used the modern XT, Deore etc. (By modern I mean late 2000's). They set up easier, shifter faster/crisper, work just fine in friction or index mode, can work with brifters if you want, wrap a lot of chain and are easy to come by cheap and in almost new condition, on the used market. Blasphemy? Sure. But if shifting this good is wrong, I don't wanna be right!

My Bike w XT long cage:

[IMG][/IMG]

furballi

I run a long cage Deore LX from a few years back along with Shimano 600 8-speed downtube shifter. Nice crisp accurate shift with each click of the lever. Much better than the stock Shimano 600 short cage.

https://www.google.com/imgres?imgurl=...9QEwAg&dur=327

balindamood

My thought is that in 1980+/- 5 years, Suntour long cagers worked better than anything else (ok, the Duopar worked nearly as well, but it cost more and was not as reliable). However, 30-years later, things ought to have been refined...and they have been. Modern Deore stuff does work better. How much better is another debate.

cyclotoine

the cable routing on the shadow derailleurs is a huge improvement over the cable loop as well. Like Brian says... how far can they take the derailleur? They change the geometry continually, and make it lighter and stiffer and better and now that gave added a clutch (pretty cool for mountain bikers)... but I mean it is a cluncky and vulnerable part. i love derailleurs, i think they are beautiful like everyone else.. but come on. how old is this technology with all those exposed cogs! In 40 years there will be no more derailleurs.

mkeller234

I wondered the same thing as the OP. I bought a modern Deore XT SGS "shadow" rear derailleur for it's insane chain wrap capacity. I've used it a lot, both in friction and indexed with 9 speeds. It's definitely nice: versatile, reliable, smooth. Once in a while shift is so quiet or smooth that I wonder if it actually shifted.

As lovely as it is, I wouldn't go as far to call it leaps and bounds better than good classic equipment. Still, get one. Experience something different. It's fun to examine the differences.

Edit: Cyclotoine is right about the cable routing on the shadow models, that is a HUGE improvement!

Creme Brulee

It is better but I feel that once you pass certain point in performance it doesn't really matter. How much better than good shifting does one really need?

spacemanz

Before I decided I needed an Italian bike with Campagnolo, to try out, I was riding a Shimano 9-speed mix, with an XTR RD, and that's a sweet RD. I think it's a RD-M952, which was 8-speed I think, but it works just fine with 9-speed, & "probably" 10, if I ever tried it, which I don't plan. I also have a lone 8-speed XTR shifter pod, also acquired used (late last year), that I haven't ridden much, but obviously, they work great together. I'm going to put those on the old C'dale Silk Road, and try again for a weight weenie ride.

ElliotSF

Thanks, all! Because of your encouragement, I just today bought on eBay an LX M581. Brand new for $22. Am excited to try it.

Sixty Fiver

I am really happy with the SRAM X5 I use on my P20 and my touring bike (barcons with friction)... both have some large chain wrap requirements that cannot be met by my favourite Suntour derailleurs and the action and performance is rather excellent.

If I did not need the SRAM I'd be using my Suntours as when it comes to friction shifters, Suntour still tops my list.

The Golden Boy 

There's plenty of reasons to be "into" "vintage" bikes. Not the least is the very refined style. Up until the mid 1990s, derailleurs had that clean, graceful look.

Although there may be plenty of reasons to like the XT and LX derailleurs pictured here, they're certainly a different stylistic attitude behind them.

jimmuller 

I've experienced that many times with a 1st gen Cyclone GT paired to a modern Shimano FW and SRAM chain. So quiet and smooth I can't tell it shifted except that the cadence changed a little. Other derailleurs such as a simple Vx-S come close too. I think it is as much due to the chain and FW as the derailleur.

Grand Bois

My best shifting derailer is an Ultegra 6500 GS. I haven't tried anything more modern, but I'm tempted to give that ugly Shadow a try if I can find a good deal on one.

It's my impression that the Suntours were great in their day, but derailers have come a long way since then.

T-Mar

Yes, the modern derailleurs are generally better. However, to optimize the performance of any derailleur, make sure you use HyperGlide compatible cogs and chain. More often than not, this makes a bigger difference in shifting performance than a new derailleur.

LeicaLad 

Without doubt, I am in the Rip Van Winkle category on rd technologies.

I would greatly appreciate the opportunity to experiment with something "almost" modern, meaning my friction shifters can still work.

What would be the most/best recommended model of the "new" Deore, or similar, rear derailleurs for such purposes of experimentation?

The shadow thing above looks interesting -- and to Rip's eyes, totally alien!

Thanks!

fender1

These work well in friction or index mode. I have used them to shift 5 speed rears through 10 speed rears. They don't look quite "C&V" but they go for way less than Suntour Cyclone long cage RD's and work really well.....

https://www.ebay.com/itm/Shimano-XT-R...item27d03fb648

John E

True. Also, I would not characterize the difference between today's best and a SunTour Cyclone II as "dramatic" or "revolutionary," assuming the latter is not suffering from pivot wear or other use-induced slop. The other thing you can do to improve your old derailleur's functionality is to replace your cables and housings, since housing compression caused much of the vagueness in older systems.

LeicaLad 

Hi guys,

Thanks. I'm certainly not complaining. And I firmly agree that 1) new chain, 2) hyperglide freewheel, and 3) new cables & housing make a HUGE difference in shifting. I have two Rally equipped bikes that shift marvelously because of these upgrades.

My question is simply motivated by curiosity. The image of the "shadow" model above is, to me anyway, alien and unknown. But it looks like it'd be fun to try.

Cheers!

furballi

Shimano LX M581 is a great value ($30 at JensonUSA after $5 new customer discount). I have one on my Centurion Ironman (large rear cog to tackle hills). To achieve the most accurate and seamless shift, be sure to adjust the B-tension screw so that the upper pulley is as close as possible to the rear cogs (without touching). You may need to add subtract one chain link to achieve this.

The "shadow" models are much more expensive. I've seen a few used "shadow" derailleurs CL for $40.

The Nashbar/Microshift 10-speed road derailleur is also very good...often under $30 after 20% off discount. LX M581 is still a touch better.

https://www.jensonusa.com/Shimano-LX-...ear-Derailleur

auchencrow

Quoted for Truth.

^ To put it kindly... (VERY kindly! )

Bikedued

If you go too high on the Shimano list these days, you will find yourself with a different cable pull, unless you're using friction mode exclusively. Add to that chains, cranks, derailleurs, shifters, and cassettes that only work well within THAT group, an it soon becomes a pain in the azz mixing and matching. I recently worked on a Cross bike where the guy wanted to keep his Ultegra RD and buy new XT Shifters. (Or was it XTR) Anyways, he end up having to order a new XT derailleur because it simply didn't work correctly.

TO be honest, in my humble opinion derailleurs hit their peak about 10-12 years ago.. Everything now is so damn finicky and delicate, and wear items are made to be lightweight instead of long lasting. Everything high end is now race only, or light normal use.,,,,BD

Don't get me started on Sram. It's IMPOSSIBLE to get the rear wheel out of the frame without nearly damaging the derailleur. The upper end shifters big levers do not return to position within a few weeks out of the box. I saw a brand new X9 derailleur mounting bolt snap off, and it was a warranty replacement for the original? No outward signs of force or damage, on the first ride, snap! The lower end stuff like X5 and below works fine and is durable(heavy though). Had X-4 on my 09 Specialized, and no complaints on it besides the getting the wheel off thing.

zukahn1 

I'm a big fan of both these DR's I have both in parts bin and have ridden them on Daily riders. I for one would go with the Deore if your not worried about period correct it shifts a little nicer and is lot easier to get in good shape. While the nicer Suntour stuff may have been close when new it is pretty hard to find good Suntour without buying a whole bike or paying way to much, the last time I sold a nice VXgt I got $60 for it. Plus the Doere offers the option of using a variety of freewheels/cassettes and shifters indexed 6-9 speed.