OneUp RAD Cage Hacks Shimano Rear Derailleurs to Better Fit Oversized Cogs

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

OneUp Components has introduced a few firsts in the oversized cog game, namely the 16T replacement cog. Now, the RAD Cage boosts derailleur performance at the top end of the cassette without having to reverse or extend your B-Screw.

Made for modern, clutch equipped 10-speed Shimano Deore, SLX, XT or XTR medium cage rear derailleurs, it repositions the upper pulley to improve tooth and chain clearance over 40 and 42 tooth cogs. I installed it on my Niner RIP 9 RDO, which was already running their 40T and 16T cogs. When originally setup with those two parts, I had to bury the B-Screw all the way, which just barely left enough room between the pulley and the largest cog. There was no way OneUp’s (or anyone else’s) 42T cog was fitting in there without more drastic measures. Until the RAD Cage, anyway…

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

The RAD Cage kit includes the outer cage and a new mounting screw since you’ll use the original to bolt the pulley to its new location.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

The big hole in the middle is the original location of the pulley. On the RAD Cage, it’s simply where you’re reattaching the cage to the derailleur. The pulley gets bolted to the smaller threaded hole just behind it (not the one showing silver threads in this pic, the other one that’s showing green threads).

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

Size is virtually identical, and marks are clearly etched on the outside face so you know where to reinstall the clutch’s tension spring. XTR uses a different hole than SLX and XT.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

Before and after shows the pulley slightly higher and rearward. It’s not just improving the position on the big cog, it allows for a bit more chain wrap on the smaller cogs, too.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

The only downside? It adds about 11g.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

Well, that, and good luck getting this little C-clip back in place. I haven’t had enough trail time on it yet to see if the bolt comes loose, so look for the long term report in the future. Shimano’s known for doubling up on security measures for bolts and parts elsewhere on the bike, so hopefully this is just redundant.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

The installation requires disassembly of the clutch mechanism and removal of the cage. It took me about 20 minutes including photography and running back and forth to computer to watch OneUp’s install video. So, pretty quick and straight forward with standard tools most folks already own.

The pic above shows how much the pulley is offset from center line, and this diagram illustrates it in action:

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

On the small cogs, the pulley sits up a bit higher, wrapping the chain around the cog just a bit more. As you run up the cassette, it shifts downward to create more space.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

On the 40T cog, it allowed me to back out the B-Screw about 1/8th an inch, which improved chain wrap on many of the cogs.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

Plenty of room now for a 42-tooth cog.

OneUp sent a 42T cog that I’ll be swapping in to test clearance, but the pic above shows how much room is gained by burying the B-Screw. Which is the secondary benefit of the RAD Cage, you don’t need to flip your B-Screw or get a longer one and lessen chain wrap for the rest of the cogs. More chain wrap means better performance and longer cassette life.

OneUp Components RAD Cage replacement Shimano derailleur cage to offset pulley for oversized rear cogs

Trail time coming up soon, stay tuned. In the meantime, the RAD Cage is available now for just $35. Also available in Black.

Install Video:

20 Second Promo Video:

OneUpComponents.com

Comments

Francois - 06/23/14 - 4:03pm

SRAM PLEASE IN BLACK!!!!!!!!!

Frank - 06/23/14 - 4:26pm

In addition to reversing the b-tension screw so the head of the screw gives you an extra ~3mm of spacing, you can also go to the hardware store and get a longer screw for less than 50¢

I’d recommend trying these <$1 solutions before dishing out $35 and disassembling your derailleur.

Heffe - 06/23/14 - 4:41pm

Very cool, and glad to see it come in a color other than green.

pedalist - 06/23/14 - 4:56pm

They’re sprockets, not cogs. SPROCKETS!

tim novak - 06/23/14 - 4:58pm

who cares about 42t cog i want a 10t

Roy - 06/23/14 - 5:11pm

that is freakin awesome! A little company like OneUp, one upping Shimano with the ability to run a 42 and get a bit more gear range for a measely price to boot. The wrap on the smaller cogs is critical to good shifting, a screw from Lowes does not do that. I am a huge fan of 1X SRAM for the range of gearing, but this is getting closer without the big $ of a full drivetrain.

Ripnshread - 06/23/14 - 5:48pm

Nice

Padrote - 06/23/14 - 8:03pm

Don’t assume for a second that this will actually shift as well as a bespoke 11 speed design. Especially one that doesn’t have to use that huge cage.

muf - 06/23/14 - 11:09pm

yeah id like that on my sram derailleur.. with a 42t too, obviously ;)

NSXTC - 06/23/14 - 11:36pm

“Shi-man-o”

Jr - 06/24/14 - 12:14am

Yeah SRAM is still a lot better…but props on the nice Frankenstein drivetrain look! Quit being cheap and buy the new gear. Lord.

Sevo - 06/24/14 - 12:42am

One Up…you guys are brilliant. Created the market, then offered a 16t cog replacement, and then this.

Bravo

Aaron - 06/24/14 - 12:59am

Further proof that people would rather spend money than pedal harder. Man up and ride an 11-32 like the old days!

iperov - 06/24/14 - 1:47am

I aspire to the contrary remove weight from the wheel
-_-

Scrooge McDuck - 06/24/14 - 4:26am

This is pathetic. If it’s going on my XTR dérailleur it needs to be carbon. Why else would I have bought XTR?!

scott - 06/24/14 - 7:38am

Couldn’t I just drill and tap my stock cage to move it to that location? I’m going to try it out on my deore shadow + since its so cheap.

Offrhodes - 06/24/14 - 8:27am

@Aaron, you mean 12-28….and 7 spd?

dougal - 06/24/14 - 3:24pm

Offrhodes,

Yes, those were the days. 11-28 in back and a 26-36-46 up front. Make sure you were running a 150mm stem with a 19.5 inch bar and everything would be perfect!

MBR - 06/27/14 - 2:36pm

I wonder if this would increase chain wrap and improve shifting on a stock 11-36 cassette?

MBR - 06/27/14 - 2:42pm

Re: “The Days”
First mountain bike was a Jamis Dakota with a 1:1 granny. 28-38-48 Biopace rings and granny in the 6-spd cassette was a 28. Rule-5: Toughen the f*** up.

Dave - 06/29/14 - 5:48am

You Can get scrambled eggs out powder as Well..

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