What XTR/XT RD do I need for hillclimbs?

[tv_vt]

I'm thinking of setting up a road bike for serious hillclimbs. Using 9 speed Shimano Dura Ace shifters - what would be the appropriate XTR/XT rear derailleur to use? I'm not up on all the different models.

Will be using a 32 or 34 tooth low end cog in back (11-32 or 12-34 cassette) with a compact 34 in front.

Thanks!

Thom

[dave thompson]

You can use any Deore, XT, XTR 9-speed 'normal' derailleur, all will work well with your Dura Ace components. If you have a triple crank you should use the long-cage models, with a double you can use either the long or medium cage models.

No real need to spend the money for the XTR as the others will work as well for a lot less.

[HomardBreton]

.... I would suggest a 28T cog ( DA 7900 or similar ) and a 39T small ring in the front. Perhaps a compact crank if you like these; I´ve done several climbs in the alps this spring and only used the 28T ring ( with the 39er in front ) twice for a short time while climbing up some of the famous cols. Only if the climbs are very steep ( above avg. 18% for more than 3 km ) I would go for a larger cog...

[thwart]

above avg. 18% for more than 3 km I dunno... for me, if it's above 18% for more than a couple hundred meters or so I'd like the gearing options the OP mentioned above.

But, then again, I'm weak and old...

[dave thompson]

I love young guys that have the legs to do huge climbs with 'normal' gearing, chapeau! As for me, being surrounded by several mountain ranges and *lots* of hills and accepting my age limitations for climbing them, I've surrendered to the "there's no such thing as too low a gear around here" thing. Compact cranks and an 11/32 cassette make my knees/legs/mind very happy.

[torquer]

FWIW, most Mt. Washington veterans recommend a 1:1 ratio, at least as an insurance "granny", so 34T chainring with a cassette with 32 or 34 teeth sounds right. (Unless you have a pro team contract, of course.)
That's for an average 12% climb, with pitches close to 20%, after an hour+ exertion. 9 speed Shimano road cassettes max out at 27 teeth; some folks here have reported that 28 tooth setups work, but that's about the limit before you need a MTB rear der.
Another "serious hillclimb" example: Whiteface Mtn. (8 miles at 8%, no more than +/- 1 or 2%); 34 (compact) front x 27 rear can be "spun" for a one-hour time (midpack for good, young climbers, podium threat for 50+ age group.) First year I tried it, it was on a 39x27 combo, and my legs didn't recover for months. YRMV.

[palincss]

You get the gearing you need. It's foolish to let someone whose needs and capabilities are radically different from yours to dictate your gearing.

In this case, I thought the question wasn't did the OP need low gears, but rather what rear derailleurs would work with his shifters. As far as cable pull compatibility goes, they all work. However, there is one significant difference to keep in mind: some late model MTB rear derailleurs no longer have a derailleur body cable adjustment. Unless you want to add an in-line adjuster, that could turn into a major pain at some point.

Also some MTB rear derailleurs work "ass backwards" -- aka "Rapid Rise" -- where when you slack off the cable it shifts to the largest sprocket rather than the smallest one. About the only ways this works out well are if every bike you own is configured this way, or if this bike has a totally unique style of shifter that's different from all your other bikes. If you try to mix and match, you'll never keep it straight and inevitably will end up shifting the wrong way at the worst possible time.

[HomardBreton]

...I´m not soo young any more. But I have had a racing career in the past, which makes it a lot easier. And a plus will be also, that I´ve got a weight of appr. 150 lbs. at a height of 188cm. So I´m alucky one, who´s having a perfect weight / power - ratio to climb up the hills.

And compact with lower ratio ( 28 / 32 T ) is easier, looks easier - and ist more the style of Lance Armstrong. He´s riding those low gear ratios too..

[tv_vt]

Torquer and Dave have it about right. New England hillclimbs are steeper than most Alpine climbs, I think. A few weeks ago I did the Ascutney Mtn hillclimb in Vermont - average 12% grade for 4 miles, with pitches of 19% or so. I used a 34x30 setup, which was OK, but I still found myself weaving in some sections. A 1:1 setup, or even higher (34 front x 36 rear) is not out of line if you want to spin a little. BTW, I used a regular Dura Ace 9 speed RD for the 34x30 setup, with no problems. For me, it's a 40-45 minute climb. Fastest climbers do it in less than 30 minutes.

Years ago, I did that climb with a 39x27 setup, but I don't think it would be a good approach now!

Anyone know what MTN RD model numbers to look for? I looked at XTR RD on eBay and saw a huge array of model numbers: M952, M950, M972, etc...

Thanks,

T

[Gummee]

I was going to point you towards the DA long cage, but the web sez it only goes up to 27t too. Odd. You'd think it'd go higher.

AFA the OP: Any of the M95X series will work great. Same cable pull. Traditional looking rear derailleur. If you can find an M900 XTR it'd be even better. Similar finish to the rest of the bike.

I've taken XTR derailleurs and swapped cages long for short. I don't remember if I've done XTR to DA*. I KNOW I've done Ultegra and XT. You may want to think about going that route if you have 'leftover' parts.

HTH

M

*the XTR on my mtn bike is made of 3 different roached rear derailleurs.

[HomardBreton]

...the new DA RD-7900 is going up to 28T, interchangebility for older cassette sprockets should be no problem...have a look at this flipchart:

http://www.bike-components.de/download/shimano/interchangeability.jpg

can do a total difference of 33T.

[tv_vt]

Homard, thanks for that link, but I'm looking for a RD that could handle 34 tooth cogs.

Gummee, I wonder if I could pick up a longer cage from QBP or somewhere. I could swap it on to an Ultegra 6500 RD, maybe. Thanks for the tip.

[dave thompson]

The new 6700 rear derailleur, and I suspect the 7900 is similar, has a slightly different geometry from its' earlier brothers (6600/6500) which allows, at least on my bikes, me to use a short cage 6700 derailleur with an 11/32 cassette. Adjustment of the B-screw will let the top pulley clear the large 32t cog.

[dave thompson]

Homard, thanks for that link, but I'm looking for a RD that could handle 34 teeth cogs.

Gummee, I wonder if I could pick up a longer cage from QBP or somewhere. I could swap it on to an Ultegra 6500 RD, maybe. Thanks for the tip.
Thom, it's not the cage length that is critical when running a large cassette, it's the ability of the top pulley to clear the large cog. The 9-speed derailleurs simply don't have the geometry to do that. Cage length has to do with chain wrap, not pulley clearance.

If you run a 34t cassette you will need an MTB derailleur. I've experimented quite a bit with derailleur/cassette combinations and I have not found any Shimano compatible road derailleur that will clear that large a cog. Been there, done that and have the empty boxes to prove it!

[endosch2]

I rode Mt wash twice - I had a 24/ 28 and shifted to a 24/25.

It is brutal - you definately want sub 1:1.

[dave thompson]

...and if you get really desperate for gears, you can use a Shimano 12/36 cassette with a MicroShift MTB rear derailleur.

[Gummee]

Homard, thanks for that link, but I'm looking for a RD that could handle 34 tooth cogs.

Gummee, I wonder if I could pick up a longer cage from QBP or somewhere. I could swap it on to an Ultegra 6500 RD, maybe. Thanks for the tip.
Your better bet is troll the LBSes for 'roached on the top' rear derailleurs. Its sorta a PITA cause you need 3 hands, but if you already have the stuff...

The XTegra I built ran fine on big cassettes. :dunno

M

[Mark McM]

It sounds like you are interested in setting up your bike for the B.U.M.P.S. series hillclimb races. If this is the case, then it might be the better bet to change the crank/chainrings than the cassette/derailleur.

The problem with using an MTB cassette is that there are large jumps between sprocket sizes, so it is more difficult to find just the right gear for a stretch of road. Road cassettes have more closely spaced gearing, making it easier to find just the right gear.

So, rather than getting a bigger cassette, and then trying to jigger the shifters and derailleurs to work on a road bike, it is usually easier to swap the crank.

The B.U.M.P.S. series hillclimbs can usually be done with a single chainring. So, get an MTB crank, remove the two large chainrings, and just go with the single inner chainring. Depending on the crank, you may not even have to change BBs (I use square taper cranks, and I've never had to change the BB when swapping between square taper road and MTB cranks). With a single chainring up front, you can also remove the front derailleur (further lightening the bike!).

Using an MTB crank generally means that you can leave the rear half of the drive train just as it is. The only additional modification to get the rear shifting correct is to shorten the chain to compensate for the smaller chainring.

[palincss]

...and if you get really desperate for gears, you can use a Shimano 12/36 cassette with a MicroShift MTB rear derailleur.

You'd think Shimano would have made a MTB rear derailleur that would work with their 12-36 cassette.

[palincss]

Your better bet is troll the LBSes for 'roached on the top' rear derailleurs.


What does that mean?
:confused:

[Straz]

I did exactly as Mark McM describes. I participate in some of the BUMP events and run a 11-28 cassette and a triple crank with 26-42 chainrings. 42t is nice for when you have to ride back down and the spread on a 11-28 cassette is smaller than the 32t+ MTB cassette.

Tim

[eddief]

that is to run a Shimano long cage 9 speed rear d with 9 speed 12-36 cassette. Maybe I had to install longer B screw though to keep the jockey off the big cog.

not any more though as I have switched back all the bikes to road triple fronts and up to 34 on the rear.

You'd think Shimano would have made a MTB rear derailleur that would work with their 12-36 cassette.

[Gummee]

What does that mean?
:confused:Someone wrapped the derailleur around their stays but the cages are still straight. Typically the b-tension plate and fixing bolt are trashed. Since he doesn't need those, they don't matter.

What DOES matter is that the cages are straight

M

[Chance]

I did exactly as Mark McM describes. I participate in some of the BUMP events and run a 11-28 cassette and a triple crank with 26-42 chainrings. 42t is nice for when you have to ride back down and the spread on a 11-28 cassette is smaller than the 32t+ MTB cassette.

Tim
This is going off topic since tv vt didn’t ask about close ratios for climbing. Nor is it meant as a response to your setup which is very good.

When selecting Shimano 9-speed cassettes specifically for big climbs, gear ratios for an 11-28 versus 11-34 are deceptively similar in the gear range that the rider would be using on steep grades. Options to obtain both 1:1 low-end and also close ratios in the climbing range of the cassette are difficult to achieve.

Note below that the largest 6 cogs give a 2:1 range for both cassettes.

11-28 = 11-12-13-14-16-18-21-24-28 (fits most road bikes with road RD)

11-34 = 11-13-15-17-20-23-26-30-34 (requires mountain RD on most bikes)

As percent of change, jump between 24-28 is bigger than 30-34. And although 21-24 is better than 26-30, 18-21 is bigger than 23-26. Over largest 6 cogs jumps average to the exact same.

1:1 low end and close ratios can be done with a custom cassette (build your own), using mountain or triple granny chainring (24 or 26 tooth) with 12-25 cassette, or if you can find one a junior cassette with 25 or 27 tooth cog which has close ratios at expense of top end.

14-25 = 14, 15, 16, 17, 18, 19, 21, 23, 25

What tv vt wants to do for a pure climbing bike may not be ideal because of wide ratios but is a good compromise. It’s easy and inexpensive.

[oldpotatoe]

Homard, thanks for that link, but I'm looking for a RD that could handle 34 tooth cogs.

Gummee, I wonder if I could pick up a longer cage from QBP or somewhere. I could swap it on to an Ultegra 6500 RD, maybe. Thanks for the tip.

Not going to find a cage in QBP..just get a XT or even better, Deore standard(not low normal) with a barrel adjuster. Not the shadow type.

[oldpotatoe]

You'd think Shimano would have made a MTB rear derailleur that would work with their 12-36 cassette.

They do, a shimano MTB 9s rear der, like a Deore rear der, with 10s ROAD shifters..have done this more than once with shimano 10s STI. shimano 10s MTB rear der not compatible with road 10s STI,, btw..

[SpeedyChix]

I'm thinking of setting up a road bike for serious hillclimbs. Using 9 speed Shimano Dura Ace shifters - what would be the appropriate XTR/XT rear derailleur to use? I'm not up on all the different models.

Will be using a 32 or 34 tooth low end cog in back (11-32 or 12-34 cassette) with a compact 34 in front.

Thanks!

Thom

The XT spring works really well for this. A bit better than the XTR.
For something like Iron Cross I've used a 34x48 compact crank up front, XT rear, mtb rear cassette with a 34t large cog, mated it all to the 9-speed Shimano road shifters. Swapping out to the normal setup I just keep the ST rear der, longer chain from that set up, the housing packed together ready for the next time I need it.

[shankldu]

I Have a nine speed xtr for sale 970 model in good shape $80 plus actual shipping

[DHallerman]

I was going to write the same thing, and both points are very, very significant.

* You want the older models of XTR or XT that have the cable adjuster built in.

* You do not want Rapid Rise, unless you like the idea of relearning shifting patterns on a road bike.

You get the gearing you need. It's foolish to let someone whose needs and capabilities are radically different from yours to dictate your gearing.

In this case, I thought the question wasn't did the OP need low gears, but rather what rear derailleurs would work with his shifters. As far as cable pull compatibility goes, they all work. However, there is one significant difference to keep in mind: some late model MTB rear derailleurs no longer have a derailleur body cable adjustment. Unless you want to add an in-line adjuster, that could turn into a major pain at some point.

Also some MTB rear derailleurs work "ass backwards" -- aka "Rapid Rise" -- where when you slack off the cable it shifts to the largest sprocket rather than the smallest one. About the only ways this works out well are if every bike you own is configured this way, or if this bike has a totally unique style of shifter that's different from all your other bikes. If you try to mix and match, you'll never keep it straight and inevitably will end up shifting the wrong way at the worst possible time.

[NHAero]

HI Thom
I have several bikes here with long cage XT and XTR rear derailleurs. The XT are generally RD M750 SGS long cage and the XTR are RD M952 SGS long cage. I'm not sure what the largest cog is on the bikes but it must be at least 32 on the MTBs. All of these derailleurs are set up as 9 speeds and all have cable adjusters.

I'm thinking of setting up a road bike for serious hillclimbs. Using 9 speed Shimano Dura Ace shifters - what would be the appropriate XTR/XT rear derailleur to use? I'm not up on all the different models.

Will be using a 32 or 34 tooth low end cog in back (11-32 or 12-34 cassette) with a compact 34 in front.

Thanks!

Thom

[Louis]

Not going to find a cage in QBP..just get a XT or even better, Deore standard(not low normal) with a barrel adjuster. Not the shadow type.

Peter, why not the Shadow type?

Is a 9-spd Shadow R-der not compatible with 9-spd STI road shifters? (or in my case, 9-spd DT shifters?)

I assumed they were, but that's only because I hadn't seen anything that said that they were not. Your statement is the first I've seen that implies that.

Thanks
Louis

[dave thompson]

The Shadow version derailleurs have no barrel adjuster on them, which could be a large problem on a bike with no adjusters on the down tube cable stops.

[Louis]

The Shadow version derailleurs have no barrel adjuster on them, which could be a large problem on a bike with no adjusters on the down tube cable stops.

Ah, I see. Thanks Dave.

[oldpotatoe]

Peter, why not the Shadow type?

Is a 9-spd Shadow R-der not compatible with 9-spd STI road shifters? (or in my case, 9-spd DT shifters?)

I assumed they were, but that's only because I hadn't seen anything that said that they were not. Your statement is the first I've seen that implies that.

Thanks
Louis

They are but after installing one, it just didn't work as well as the deore I replaced it with. Perhaps it was the 'plug-in' barrel adjuster I put into the hole of the Shadow one, perhaps it settled in and unadjusted the RD but the more traditional 9s MTB TD worked better.

[572cv]

Way back in the day, when wife and I did Mt. Washington, she knew enough to put serious pie-pan gearing on the cluster. We used, I think, a Cyclopans setup which went to at least 32- maybe it was 34. Once you shifted into those, though, you couldn't easily drop back down with Campy NR. Mt Washington has zero places to recover, so you have to keep below your anerobic threshold until you see the finish line, pretty much.

There are lots of climbs in Vermont, though, and we are both getting to a, ahem, place in time where, like DaveT, no gear is too small if it is comfortable. We have climbs over 20% in places within 30 miles of our house.

I use an Ultegra compact 50/34 with a sram 11/28 rear cluster most of the time. The Ultegra rd can handle the 28 no problem. We redid her bike this year with a sram force group, compact crank, but used an Apex RD. This will handle anything. Her bike has a 32 for the big cog. This setup works nicely.

[BillG]

I have my climbing dirt road VT rando bike set up with a Red Compact on the front and XT/11/34 on the back. It gets you up Lincoln Gap and Fuller Hill Road! Strongly suggested for Vermont style super steep climbs with lots of +20%.

[BillG]

.... I would suggest a 28T cog ( DA 7900 or similar ) and a 39T small ring in the front. Perhaps a compact crank if you like these; I´ve done several climbs in the alps this spring and only used the 28T ring ( with the 39er in front ) twice for a short time while climbing up some of the famous cols. Only if the climbs are very steep ( above avg. 18% for more than 3 km ) I would go for a larger cog...

A lot of these New England climbs are dirt roads when they get real steep (Lincoln Gap is a sustained 20-25% over a mile). It's useful to have something low when you can't stand and need to move your weight over your bars so you don't flip over!

[beungood]

It sounds like you are interested in setting up your bike for the B.U.M.P.S. series hillclimb races. If this is the case, then it might be the better bet to change the crank/chainrings than the cassette/derailleur.

The problem with using an MTB cassette is that there are large jumps between sprocket sizes, so it is more difficult to find just the right gear for a stretch of road. Road cassettes have more closely spaced gearing, making it easier to find just the right gear.

The B.U.M.P.S. series hillclimbs can usually be done with a single chainring. So, get an MTB crank, remove the two large chainrings, and just go with the single inner chainring. Depending on the crank, you may not even have to change BBs (I use square taper cranks, and I've never had to change the BB when swapping between square taper road and MTB cranks). With a single chainring up front, you can also remove the front derailleur (further lightening the bike!).

Using an MTB crank generally means that you can leave the rear half of the drive train just as it is. The only additional modification to get the rear shifting correct is to shorten the chain to compensate for the smaller chainring.

What kind of set-ups are used for these events? Better to have a dedicated bike for them?

[tv_vt]

Thanks to all for the info. Will be on the lookout for an older XT or XTR with the barrel adjusters and normal shifting, not the Rapid Rise. The things you learn here!

As for the Q about the BUMPS series, yeah, a dedicated climbing bike is pretty common. I've only done Ascutney, but you can tell from standing around the start line, there are some serious mountain goats lurking. Lots of single chainrings in the 20-30T range, as an earlier poster mentioned, with pie plates in back. One of the more interesting setups at Ascutney last month was this guy, easily mid-60s, with what looked like a straight bar hybrid bike, like the kind you'd ride around your RV park, with lots of low gears. ...and he blew by me, spinning happily along, around the 3 mile mark.

Hey Marc, did you get your Anderson yet?

[NHAero]

I put it on hold for the moment. I want to get a proper fitting, and I'm not riding far enough here on the Island, 30-35 milers at a whack, to matter what I ride, so it doesn't feel like a rush.



Hey Marc, did you get your Anderson yet?

[bigreen505]

Personally, I would go with a triple. That will allow you to get the gear ratios you need with smaller jumps between cogs.

[Mark McM]

What kind of set-ups are used for these events? Better to have a dedicated bike for them?

Some people have dedicated bikes, but I usually just do a quick switch-over on my road bike for the event.

For me, the switch-over consists of:

- Swap regular road crank with an MTB crank (both are square taper, fit on the same BB so no swapping of the BB required). The two largest chainring are left off the MTB crank

- Swap chain with a second, shorter chain (to compensate for the smaller chainring). Removable chainlinks found as standard on many chains (SRAM, KMC, etc.) make this a 2 minute job.

- Remove front derailleur.

Other than that, I use my standard road bike setup (including rear derailleur and cassette).

The swap in each direction takes less than an hour. I'll do the swap a day or two before the event so I have a chance to check out the operation of the drivetrain.