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Leonardi Factory oversizes derailleur pulley bearings & monster 12-speed MTB cassette

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Wide range derailleur hop-up kits keep popping up, with the emphasis now being on ways to either lessen the cost of getting an Eagle-equivalent range, or making your 11-speed group behave like it has more. Or, in the case of Leonardi Factory, doing all that and making things run a little smoother.

To do that, they’re offering derailleur pulley upgrade kits that mold the teeth out of Arnite composite, which they say is the hardest plastic available. So it’s super quiet and durable…

 

…and efficient because they’re rolling on oversized bearings. Not oversized pulleys, rather, bearings with a larger inner and outer diameter. They make specific versions for upper and lower pulleys, and each one will run $39 (so, $78 to outfit a derailleur. They also offer Max Speed cable tension pulley replacements ($30) to help the shift cable move in and out of the derailleur just a bit better.

Visible on the top photo, they also make replacement inner cages ($44) for SRAM MTB derailleurs, which are cold forged then CNC’d. They say they’re bit lighter than stock, but we think the main upset is that they come in colors.

For cassette upgrades, they offer this 12-speed 9-48, which they say translates to a 533% range. The benefit? Smaller jumps between gears and more range. Claimed weight is 344g.

For those still rocking 11-speed, there’s a 321g 9-45 that offers 500% – Same range as Eagle, and you only need to replace the cassette. Both run on the SRAM XD freehub body standard.

The cassettes use a two-piece machined construction, cut from steel and aluminum. Retail is $425.

Gecko Track ovalized chainrings have a very flat section, almost rectangular. So, their 28-tooth chainrings are equivalent to moving between a 32t in the power stroke and a 26t in your dead spot.

LeonardiFactory.com

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Aaron
Aaron
5 years ago

Hey, aren’t those kind of the same idea as the enduro bearings pulleys that have been out for a year?

name name
name name
5 years ago

“efficient because they’re rolling on oversized bearings. Not oversized pulleys, rather, bearings with a larger inner and outer diameter.”

No! The whole point of a small bearing and a large pulley, is to reduce the bearing drag torque. The large pulley also has the advantage of the chain links have to ‘bend’ less. This system provides none of the aforementioned positives and I can’t see any good reason for doing it this way, apart from marketing BS.

Regards,
A mechanical engineer working in the field of bearings

TimE
TimE
5 years ago
Reply to  name name

Bingo! The size of those balls is so tiny that any grit will result in a seized bearing

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