Kogel has just announced that they’ve entered the oversized derailleur pulley game with the Kolossos. If you’ve read up on the Kogel blog, you know that the company hasn’t been behind the idea that oversized cages were an improvement for all riders. So what changed? According to owner/founder Ard Kessels, that all comes down to stiffness and better shifting accuracy.

Kogel Kolossos oversized derailleur pulley cage ceramic bearings Kogel claims that competing oversized cages are more flexible and when combined with lower spring tension, negatively affect shifting accuracy and chain retention. In some cases, this may be acceptable, but in instances where crisp & accurate shifting is required, Kogel has always maintained that stock was better.

Enter Kolossos. With a cage that Kogel claims are the stiffest on the market, Kolossos claims to be 3x stiffer than the competitor’s oversized cage and 2x stiffer than a stock cage. According to Kogel, this should make the Kolossos better equipped for both road and offroad riding making this an intriguing option for gravel bikes.

Due to the added stiffness and chain retention features, Kogel says the Kolossos is a bit heavier than competitors at around 80g for the entire assembly depending on the model.

Kogel Kolossos oversized derailleur pulley cage ceramic bearings

The lower pulley has a longer tooth profile for improved chain retention and a chain catcher feature that claims to prevent chain jams. Fully serviceable, the Kolossos includes a 19t lower pulley and a 12t upper pulley, both with ceramic bearings.

 

Kogel Kolossos oversized derailleur pulley cage ceramic bearings

Designed to fit Shimano derailleurs, the Kolossos will be offered in versions to fit Dura-Ace R9100 and Ultegra R8000 as well as RX800 and GRX derailleurs. The cage will fit both SS (short) and GS (medium) cage derailleurs out of the box, and will eventually be offered in custom colors. At the launch, the Kolossos will be available in Black, Fire Engine Red, and Midas Gold and is priced at $400 (with pre-sale pricing of $350). The DA R9100/R8000 model will be available first at the end of January followed by the RX800/GRX model in February.

kogel.cc

28 comments

      • Mark on

        I read your blog and still don’t get it. The top pulley on my Campy derailleur doesn’t have a roller bearing; it’s a bronze sleeve, and for good reason. Do these new-fangled cages use ball bearing upper pulleys? If so, that’s bad engineering. Aside from that, the bottom pulley and cage have absolutely nothing to do with shifting. Once the chain gets past the top pulley, who cares? For what it’s worth I have a degree in mechanical engineering and 35 years of experience designing mechanical systems.

        Reply
        • Greg on

          Shimano pioneered the floating upper pulley. Over the years, and with the addition of more cogs, the amount of float has gradually reduced. Now most, if not all, of their upper pulleys are fixed. In addition, the tooth height of their upper pulleys has gotten taller. However, their current designs also abandon the B-bolt as a sprung pivot. With this, the upper pulley cannot follow as closely as before. The trade-off is that it also doesn’t vary or bounce around. Give n take.
          But I would not simply state that ball bearing upper pulleys are bad engineering. It’s so, so much more complicated than that.
          For what it’s worth, I dropped out of engineering school 25 years ago.

          Reply
          • Shafty on

            Ball bearing upper pulleys are mostly a balance of compromises. To reduce the play, you can use a bearing with less clearance, but there’s a limit while retaining free rotation. A precision bushing would be ideal, but it’s again difficult to reduce axial clearance. With 11/12 sprockets the older sliding bushings actually reduce shifting precision.

            Radial bearings live short lives when they’re not properly supported. They just don’t have the capacity for high axial and angular loads in the sizes that are used, especially with larger diameter pulleys. They’re not exactly expensive, so it’s not a problem for the majority of riders.

            Reply
          • Mark on

            Then let’s call it “just ok” and “better” engineering, The point of my comment was in response to the “Since at the heart of this system is a ball bearing and the ball bearing will need some kind of play to run lightly” statement in the blog. Not sure about these boutique systems, but both Campy and Shimano use a sleeve bearing for the guide wheel and ball bearing for the tension wheel. They do this to minimize axial and angular play in the guide wheel and friction in the tension wheel.

            Reply
            • Greg on

              Campy and Shimano did not use a bushing to reduce axial and angular play. They specifically used it to allow for lateral play. Shimano called it a floating pulley, or “Centeron”, as in self centering. Not only that, but Shimano xtr and Dura Ace nine and ten speed upper pulleys had a magical system that incorporated ball bearings AND allowed for lateral play. (I believe it was a double row bearing with an extended inner race between them). And as stated before, all their current derailleurs Ultegra and up use bearings for the upper pulley as well.

              Reply
        • OriginalMV on

          I have minimal experience with oversize pulleys (ie aftermarket pulleys larger than what comes stock on the derailleur), but over 25 years servicing quality bikes. Brass bushings are NOT better than ball bearings for long term shift accuracy.

          The bushing sleeves eventually wear and get sloppy, and the shifting degrades. This was especially true during the floating top pulley era, when the extra lateral movement magnified the pulley slop. I mean slop, in which the pulley wobbles on its axis rather than staying parallel to the cogs. That’s why Dura Ace pulleys were a great upgrade, because they have cartridge bearings on the top pulleys even though they still allowed lateral float. Ultegra pulleys were decent because their ceramic bushing top pulleys outlasted 105-level and lower brass bushings. For DA and Ultegra one generally kept them until the pulley teeth were super worn, while cheaper pulleys were replaced when the top pulley started to flop regardless of how much wear was on the teeth.

          Now that drivetrain manufacturers have moved to 11-tooth or larger pulleys with no float on the top position, the onset of top pulley slop seems to be delayed. But SRAM road derailleur pulleys have had bearings on even the entry level since the mid-00s, and those things last great.

          Campagnolo pulleys were middling at best during the brass bushing/floating top pulley era (pre-11sp). Current Super Record pulleys are nice, but it’s rather disappointing that they haven’t trickled down better stock options on the less expensive derailleurs.

          My guess is that quality ceramic bearings probably won’t make a night and day difference in shifting accuracy in these really big oversize pulleys vs steel bearings…but I bet they would maintain performance in the long run with less drag. However I am sure that brass bushings would degrade rather fast in oversize pulleys while having more drag than bearings.

          Reply
  1. Crash Bandicoot on

    Would not buy, these oversized pulley systems are always seemed a bit dubious but Kogel’s normal jockey wheels fail at an alarming rate, can’t imagine that would change much.

    Reply
      • Crash Bandicoot on

        I’m sure you’ll pish posh my anecdotal experience (sorry I work in a completely different industry) a great friend and team mate of mine is a head mechanic at a large bike shop chain in the DFW area and when I’ve asked about pulley upgrades area he recounts an exorbitant amount of experiences processing warranty claims for Kogel ceramic pulleys specifically . Far more than that of Ceramicspeed and he’s never really had to warranty a Shimano or SRAM jockey wheel the only other jockey wheels that fail close to as much is very cheap off brand from China, stuff that gets brought into the shop. I have seen them fail twice on rides in the Houston area and I’ve never seen a jockey wheel fail on a decently maintained road bike before so sorry if I don’t trust the company to effectively manufacture a product like this.

        Reply
        • Ard Kessels on

          Crash, I’m sorry to hear your friend had a bad experience with our products.

          To back up your statement with some data: Kogel offers a 2 year, Guaranteed Performance warranty. It used to be called ‘very few questions asked warranty’. I am sure most customers will contact us when a product does not live up to their expectations.

          Our return rate is and has been around 2% for over five years. You can decide for yourself if that is an exorbitant number.

          The details of how we take care of our customers are outlined on our warranty page and the below blog post.
          https://www.kogel.cc/pages/product-warranty

          https://www.kogel.cc/blogs/kbba/ball-bearing-warranties-or-the-lack-thereof

          Reply
          • Belgian Masher on

            I fitted a Kogal BB and Cermaic Jockey wheels to a friends F8. He rides in all weathers…. The BB has been serviced twice and the jockey wheels once in the 10k miles he has done… I class that in the UK as damn good going.

            Reply
        • hamjam on

          If you don’t have a peered reviewed paper and underlying research, please don’t speak. I once thought that most people liked french fries, but a someone on the internet told me that I had no evidence. I felt so dumb.

          Reply
  2. alex szirmai on

    My first rockpros oversized failed 15 k into a world championship triathlon, wrapping the derailler into the rear wheel. My next try I used only oversized pulley wheels in a long cage shimano derailler. Has worked great.alexszitr

    Reply
  3. Gus Laskaris on

    Am I the only one who doesn’t have any problems shifting with the stock cage? Admittedly I am running SRAM Eagle on all of my bikes but everything from XX1 to GX works perfectly.

    Reply
    • OriginalMV on

      All stock Eagle pulleys are 12t-top/14t-lower with cartridge bearings (and ceramic for XX1), so they’re already fairly oversized and smooth running. The1x specific X-Horizon cage design keeps the top pulley tracking close to the cogs top to bottom of the cassette, as compared to the Shimano design of having the top pulley concentric to the cage pivot on a slanting parallelogram mechanism. So long story short, this product doesn’t fit your bikes and if it did it would be offering quite minimal benefits over the stock items.

      Reply
  4. Grant Petersen on

    Bigger pulleys are a good idea. Shimano intro’d them in the ’80s or so, with the Altus derailer (13t upper, 15t lower). They allow shorter cages with just-as-much chain rap. These guys, Kollosos, aren’t pioneering wacky stuff, just introducing it at the high-end. One commenter asked why, if it was better, Shimano didn’t big-pulley all of its derailers. I bet it’s because they only trickle down, they don’t trickle up, and the Altus is a low-end model. Plus, high-end shoppers might balk, and then Shimano would lose spec to SRAM and Camp. Whatever the reason, they don’t. Too bad.
    In keeping with some of the other comments: FWIW, my dad was a mechanical engineer, and some of my good friends are. (If being a human bicycle rider isn’t enough to warrant a comment!).
    I ride Altus derailers. They work well.

    Reply

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