Range find­ers

the ea­gle is no longer a pro­tected species

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WHEN SRAM’S EA­GLE SYS­TEM CAME OUT A COU­PLE YEARS AGO, IT WAS THE FIRST time a driv­e­train with a sin­gle chain­ring could boast as much range as pop­u­lar multi-ring set­ups, ef­fec­tively putting the last nail in the front de­railleur’s cof­fin. To do it, SRAM de­cided to add a gear, mak­ing all Ea­gle groups a 12-speed af­fair. Sure, they could prob­a­bly have done it with 11 gears, but then they’d be selling peo­ple one new part in­stead of five new parts. Adding a gear was a good busi­ness move.

Don’t get me wrong, I’m a fan of Ea­gle—I’ve given my last few ground-up builds the bird. The stuff works well, and it’s now more af­ford­able than ever, but what if you al­ready have an 11-speed bike that you want to get more range out of?

In the fol­low­ing pages, you’ll read about two of our pre­ferred ways to get more range out of your 11-speed sys­tem. E*thir­teen’s TRS cas­sette mounts to a SRAM XD driver body and uses a 9-tooth cog to get its 511-per­cent gear range, while One Up’s 50-tooth Shark Sprocket kit ex­tends the range of Shi­mano 11-42 cas­settes. Which­ever one works for you and your cur­rent setup, it’ll keep you push­ing those 11-speed trig­gers un­til they’re clicked out.

One Up 50t Shark Sprocket and Cage | $125

If you buy a Shi­mano sin­gle-ring bike off the show­room floor today, it’ll prob­a­bly come equipped with Shi­mano’s newer, wider-range 11-46-tooth cas­sette, but there are still a ton of SLX and XT 11-42 cas­settes out in the world. Nor­mally, my ad­vice would be to stay as far away from cas­sette add-ons like this One Up 50-tooth Shark kit as pos­si­ble, no mat­ter how much ex­tra

range they boast. The en­gi­neers at Shi­mano work re­ally hard to make their com­po­nents shift as per­fectly as pos­si­ble, and I’ve got­ten burned by jam­ming ran­dom CNC’d parts into the sys­tem be­fore— that Kooka crank might have looked rad­der than my stock STX-RC one, but it dropped chains faster than DJ Jazzy Jeff could drop a beat.

You can imag­ine then, how in­fu­ri­at­ing it was for me when this thing I re­ally wanted to make fun of ac­tu­ally worked. I mean, I’m sup­posed to can­ni­bal­ize a per­fectly good Shi­mano de­railleur and bolt on some CNC’d cage? I don’t think so. The fact that I’d gladly rec­om­mend the 50T Shark kit to my clos­est friends brings me zero hap­pi­ness what­so­ever. I don’t like be­ing wrong.

Typ­i­cally, slap­ping a gi­ant cog on the back of the cas­sette re­sults in poor shift­ing over the en­tire clus­ter. That’s be­cause get­ting the de­railleur to shift up into that new big-ass cog re­quires screw­ing in the b-ten­sion so much that the guide (up­per) pul­ley runs too far away from all the other cogs. The gen­eral rule is, the farther away the guide pul­ley is from the cogs, the slower and less pre­cise the shift­ing gets.

This is why One Up sells this as a kit with a de­railleur cage in­stead of sim­ply a cog add-on. The One Up cage re­po­si­tions the guide pul­ley so it can clear the 50-tooth cog while still run­ning close enough to the

smaller cogs for quick, pre­cise shift­ing.

The Shark Cage is a huge con­trib­u­tor to the ef­fi­cacy of the kit, but the ex­tra cogs them­selves are do­ing some heavy lift­ing too. The kit comes with two of them. In or­der to add the 50-tooth to the back of the cas­sette, you need to make room for it by re­mov­ing a cog. But if you sim­ply re­move one, you’re left with two things: a larger-than-de­sired shift, and mis­matched shift ramps. If you look closely at a cas­sette you’ll see how the shift ramps match up be­tween the cogs to de­liver the chain smoothly to each.

So, when in­stalling the cas­sette, you leave out Shi­mano’s 17- and 19-tooth cogs, us­ing One Up’s 18-tooth in­stead, which matches shift ramps, tooth shape and fin­ish so well that if ‘One Up’ weren’t stamped into the steel, you’d be hard­pressed to iden­tify it as non-Shi­mano. The 50-tooth is beau­ti­fully done as well, in 7075 alu­minum hard­ened to a T6 tem­per, with per­fectly matched ramp­ing and eight up­shift op­por­tu­ni­ties per revo­lu­tion.

It’s not the typ­i­cal hodge­podgery that we’ve seen in a lot of other cas­sette ex­panders. I’ve no­ticed lit­tle-to-none of the shift degra­da­tion that nor­mally ac­com­pa­nies these types of mod­i­fi­ca­tions. And after about 1,000 miles, some of which were on an e-bike (judge me if you want to), the al­loy sprocket has plenty of life left in it.

Swap­ping the

Shi­mano de­railleur cage with the Shark Cage is sim­ple for any­one with some me­chan­i­cal ap­ti­tude and, once in­stalled, it’s ad­justed like any other de­railleur. One Up even has thor­ough in­struc­tions on its web­site to guide users and shop me­chan­ics through the process.

Be­fore you go or­der­ing the kit, though, make sure it’s com­pat­i­ble with what you’ve got. This thing works so well be­cause it’s de­signed to in­ter­face specif­i­cally with the SLX M7000 and XT M8000 11-42-tooth cas­settes. It won’t work with any­thing else, so don’t go try­ing to run it on 40- or 46-tooth cas­settes. The Shark Cage is com­pat­i­ble with M9000, M8000 and M7000 de­railleurs. Also, keep in mind you’ll need a new chain and a big­ger chain­ring. How much big­ger is up to you.

You could go up by four teeth while main­tain­ing the low gear you al­ready have, but I like go­ing up two teeth be­cause it yields both higher high, and lower low gears.

This kit of­fers an im­pres­sive, cost-ef­fec­tive way to get a lot more range out of your 11-42 cas­sette. To be spe­cific, 19 per­cent more, net­ting you a 454-per­cent range. It’s so im­pres­sive that I’m will­ing to eat my words. If you’ve al­ready got some com­pat­i­ble parts, this thing is def­i­nitely worth the dough.

It’s not the typ­i­cal hodge­podgery that we’ve seen in other cas­sette ex­panders. I’ve no­ticed lit­tle-to-none of the shift degra­da­tion that nor­mally ac­com­pa­nies these types of mod­i­fi­ca­tions.

e*thir­teen TRS Plus Cas­sette | $250

The e*thir­teen TRS Plus Cas­sette isn’t a new prod­uct al­to­gether, but its gear range has just been widened to 511 per­cent, a range pre­vi­ously only found on the TRS Race. What you’ll get, aside from an ex­tra Ben­jamin in your pocket, is es­sen­tially the same. The TRS Plus has the ex­act same 9-46 tooth, 11-speed ra­tio, but dif­fer­ent con­struc­tion makes it a whop­ping 36 grams heav­ier. Of course, that’s still 17 grams lighter than SRAM’s X01 Ea­gle cas­sette.

What you’ll get by swap­ping your SRAM 11-speed cas­sette for this one is Ea­gle-beat­ing range for $250, without need­ing to plunk down for an en­tirely new 12-speed driv­e­train. Of course, you’ll prob­a­bly want to swap out your chain­ring for a smaller one, and re­place that scrappy old chain while you’re at it, so you’ll want to con­sider that in your bud­get.

How do these e*thir­teen TRS Cas­settes have 11-per­cent more gear range than SRAM Ea­gle, with just 11 speeds and no gi­ant 50-tooth cog? It’s that lit­tle 9 tooth at the bot­tom. With so few teeth, a one-tooth change rep­re­sents a larger gear jump than, say, a four­tooth jump up higher on the cas­sette. So, where SRAM Ea­gle pro­vides a lower low gear, e*thir­teen fo­cused on the high end. This is par­tic­u­larly good be­cause it means you can run a smaller chain­ring, which means bet­ter frame and ground clear­ance.

There are a fair amount of bikes out there that’ll only ac­cept up to a 32-tooth, which on an

Ea­gle driv­e­train, might be too small for strong riders.

To achieve the 9-tooth small cog, e*thir­teen had an en­gi­neer­ing hur­dle to over­come, namely how to get it on a wheel. Since the

9-tooth is such a small di­am­e­ter, a nor­mal cas­sette tool fit­ting wouldn’t work, which birthed e*thir­teen’s in­ge­nious so­lu­tion. The first three easy cogs, which are crafted from alu­minum, get mounted to an XD driver body by way of what looks a lot like a bot­tom bracket lock­ring and a cor­re­spond­ing pro­pri­etary tool. After I fin­ished test­ing the TRS Plus Cas­sette, e*thir­teen swapped that lock­ring de­sign for a pinch­bolt. Then the re­main­ing clus­ter of

eight cogs, ma­chined from one piece of steel, notches into that by us­ing a chain whip. Be­ing made out of alu­minum, the three large cogs are more sus­cep­ti­ble to wear than their steel neigh­bors, so you’ll be able to re­place each of the two clus­ter com­po­nents in­de­pen­dently.

Con­sid­er­ing how many patents driv­e­train giants SRAM and Shi­mano col­lec­tively own around how chains and cogs in­ter­act with each other, e*thir­teen did a good job cre­at­ing a nice-feel­ing shift. They’ve strug­gled a bit with creak­ing is­sues where the alu­minum and steel parts con­tact one an­other, which a gen­er­ous slather­ing of grease usu­ally wipes out. The only other dif­fi­culty is that, to re­move the cas­sette, you’ll need to add a sec­ond chain whip to your tool col­lec­tion.

And then there’s the rel­a­tively big­ger is­sue that the tiny 9-tooth cog gen­er­ates. A chain will run smoother on cogs with more teeth and rougher on cogs with fewer ones. Since the pitch of the chain is con­stant, the links can only bend at fixed points, so once you get smaller than a cer­tain num­ber of teeth, the chain has a tougher time bend­ing around the cog and the rollers in the links might not land right at the bot­tom of the tooth wells where they’re sup­posed to. This causes vi­bra­tion which, to the rider, feels like a rough gear, and it could also cause pre­ma­ture chain wear. For all kinds of sci­ence-y stuff, Google ‘chordal ac­tion’ and ‘poly­gon ef­fect.’ This, ac­cord­ing to SRAM, is why Ea­gle goes to 10 teeth in­stead of nine.

But for many riders, the ben­e­fits might out­weigh the costs here. You can def­i­nitely feel that the chain doesn’t run quite as smoothly in the 9, but if you geared your chain­ring prop­erly for your needs, you won’t be in that cog all day. Plus, most riders aren’t likely to be lay­ing down ex­treme amounts of torque in that gear any­way, so that rough­ness likely won’t have a detri­men­tal im­pact on per­for­mance for most.

What you’ll get by swap­ping your SRAM 11-speed cas­sette for this one is Ea­gle-beat­ing range for $250, without need­ing to plunk down for an en­tirely new 12-speed driv­e­train.

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