Rear derailleur recommendations, a very good one.

[skin and bone]

I want a fresh derailleur for my tourer. The current Shimano RD M700 Super plate is still in superb condition after several lower jockey wheels and one upper that I made as no spare was to be had.I just fancy a new one.
I like my derailleurs and have owned all of the expensive gadget ones up to 1995, still have most of them including a Huret Titanium Duopar, a Paul PG and a Suntour Mountech which was terrible. The older M700 was cheaper and better than the Huret and the ridiculous Paul offering.
Friction shift, 20T difference on front and max 32T sprocket rear, likely between 18T and 20T difference on rear. I like the look of the Shimano XTR offerings from three years ago.
So if you have used plenty of the near contemporary derailleurs, only the high quality ones mind, then please tell which are the best. Oh, and no carbon or other non metal items aside from the jockeys. Cost is not considered as I am easily parted from my money. In the olden days without internet I just bought the fanciest ones but now I can rely on other mugs who parted with good money.
Cheers.

[Brucey]

I have found various versions of XT derailleurs to be very good indeed. Pretty much any of the 9s ones (excluding the 'top normal' aberrations) are fine. XTR (if you want to spend more) nets you little actual performance benefit.

Best thing about all this is that if you drop the bike, you are not suddenly bankrupt or looking for something that doesn't exist any more....

As you might be able to tell, I have little truck with 'boutique' mechs....

cheers

[Moodyman1]

Brucey - Got any XT 9 sp in fine condition that want to part with?

[reohn2]

I'd even step one down off that,Deore do the trick just as good as XT or XTR.
I have all three on different bikes and there's no difference in performance.
As Brucey says,drop the bike on the wrong side(it's a 50/50 chance ) could make an XTR into and ex XTR

[skin and bone]

So far, so good. As i mentioned, the Shimano M700 is still going strong and was a third of the price of the very silly Paul product, maybe even less I hate to admit. I am just a sucker for something different now and then and twenty five years on the one Disraeli surely is a now. Which one did you fancy for your best bike but bailed because it cost big or looked untough, recentish?

[Brucey]

I wish I had bought a few more 9s XT ones when I could get them for £30 each tbh.

Re Deore vs LX vs XT; obviously the mechs vary from one generation to the next but I have observed the following:

Some LX versions are mechanically very similar to Deore; same weight, very similar/same pullies. Not worth paying more for LX, really; other generations are more like XT, but still are not such good value IMHO. Deore vs XT is a different matter; XT is significantly lighter in weight (not that a rear mech is the first place to save weight usually) but also has better (smoother, more durable, with decent seals) pullies. Often, the top pulley has a ceramic bushing, and the bottom pulley a sealed cartridge bearing. The XT paralellogram bushings are meant to be in better materials, too.

When new you would be hard-pushed to tell the difference in shifting between any of them tbh. But with casual maintenance the Deore will be worn out (pullies usually) in half the mileage of an XT. With the Deore, it is in with the tacx (or XT) pullies, ready for round 2. Even with careful maintenance the deore pullies will still wear eventually, but XT pulley bearings can last the life of the mech. However in either case, eventually the shifting quality degrades if the teeth wear badly.

I have a few well-used 9s XT mechs which are over ten years old now; they have seen many thousands of miles of MTBing, repeated jetwashing etc and they are still OK. I have been in the habit of occasionally rotating a spare set of pullies through about four mechs in service; I can service the pullies at my leisure that way; The top pulley is simple; I usually pop the seals in the lower pulley bearing too, and clean/regrease accordingly.

cheers

[mig]

what sort of lubrication regimes do people employ for rear derailleurs? just a good dousing in GT85 or similar?

[Vorpal]

The lubrication compendium... viewtopic.php?f=25&t=22074

[reohn2]

I've got admit the pulleys are better on the XT's,weight doesn't bother me TBH unless Deore were made of lead.
As for mech wear,pivots etc I don't think there's enough between the two to matter that much.
Deore "bushed" pulleys if serviced regularly do last,I strip and clean them then grease them ensuring the sideplates are filled with grease so it squelches out filling any voids,then when washing a quick squirt of the magical GT85 chases any water out.
The three Deore mechs I have are M531's,one came on the Kona and two were bought new on Ebay for £18 each one's on the Vaya,the other awaits.
I've worn out pulleys on the two XT mechs I own(both now with Tacx pulleys)but as Brucey says after many thousands of miles use and I too wish I would have snapped a few up when I saw them for £25 each just after a new generation was introduced.
The XTR came on the Santana tandem,I can't say anything about it other than it works,I've removed the pulleys to inspect them,marvelled ot their smoothness and put them back ,pivots have no discernible wear at around 25,000 miles.

TBH all work as they should,but then again so does Tourney ,it's how long they last and if it outweighs initial cost that proves their worth IMO but there's no way I'd pay XTR prices ,XT is as far as I indulge these days and then only for hubs(no later than M75X series,as they seemed to have design flaws after that IMHO) ,Deore is durable enough and enough to pay for drivetrain parts IMO.