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Re: The definitive thread for 1-1/2 Internal Routing headsets... (or) wtf tho?
I actually have found myself with a small business making and designing headset covers to be adapters for these integrated routing. Below is a summary of what I know. It’s certainly not definitive and applies more to mainstream brands than chinese brands, but I hope it’s helpful. I also hope, I dont make too many errors here as I try and type out what i know. The first thing to know is that there isnt a single bearing size. The bearings are sized by ID (inner diameter), OD (outer diameter), two chamfers which are denoted InnerXOuter, and by H (height). The bearing size is going to be frame specific, so you should always check to make sure you are getting the right one. For example there OD ranges from 49.5-52mm, ID from 39.5-42mm, ACB is usually [36 or 45] X 45. Different brands also have different designs for their headset compression rings and systems. Here is a rundown of the most common ones in no specific order. There is no compatibility across these systems unless you are using a system designed to provide it. FSA ACR (also used by Bianchi, Merida, Orbea, and Winspace)—uses a 40mm ID, 52mm OD, 7mm H, 36x45 bearing. How far in the frameset the top of the bearing sits depends on the brand as does the resulting design of the compression ring, but generally should sit 4mm deep in the frame. However, 2.5mm depths are also common as are 1mm depths. Compression ring is alloy and ~7mm thick. This is the most commonly used system by a wide margin and there are compatible parts made by other manufacturers. Deda DCR (used by Time, Van Rysel, Botechia, prior gen Colnago Bikes and MANY smaller brands like Standert)—uses a 52mm OD, 40mm H, 8mm H, 45x45 bearing. Compression ring is a 15-20mm deep high pressure injection molded Nylon item. Depths again can vary for specific models of bike, but most are ~4mm deep. However, Deda does make a variety of C Rings of varying heights and to fit both 45x45 and 36x45 bearings in an attempt to make their system more universal. Deda does make shims for these, but they can be hard to find. IMO, this is the system easiest to retrofit to a frame. Token/Enve (also used by no 22 and Ventum)— uses a 52mm OD, 40mm H, 8mm H, 45x45 bearing. Compression ring is composite ~7-8mm thick. These come with a set of shims and can be a good fit if you can find them. Acros (used by Canyon, Focus and Scott)—these solutions vary a lot but the most common uses a 42mm ID, 52mm 6.5mm H, 45x45 bearing. Compression ring design varies from nylon with metal inserts to just nylon and are <10mm thick. I would use this only with an Acros bearing because of the dimensions. Trek— 40mm ID, 51mm OD, 6.5m H, 36x45. Compression rings and headset spacers are nearly model specific at this point, however the Domane Gen 4 alloy compression ring and spacers are considered a service part for most of the models, so their use is Trek OK with. Unless you have a burning desire to fit a trek cockpit to your bike. Its probably best to avoid for other bikes. Specialized— 40.5mm ID, 49.5 ID, 6.5mm H 45x45 bearing, SL7/Allez sprint use an alloy compression ring, post recall this is a two part item. SL8 uses a composite ring. Both versions then use the same spacer. Their fitment varies by model again. This is again an avoid using part unless you have a perfect match in terms of bearings. The compression ring is not the right fit for non Specialized bikes and the current SL7 version is a recall fix for their specific bikes. Cervelo— 34.1 ID, 46.9 OD, 7mm H, 45x45 bearing— These use a proprietary everything including steerer shape. Of these only the FSA, Deda, and Enve are designed for aftermarket use with the first being the most common, and a lot of space between the use of the Deda system and the Token. There is no guarantee that these will fit on your bike without measuring width a depth gauge. For safety you absolutely should match both the chamfer and height. Because of the way the Deda and Token systems work you can use shims inside the headset. With Deda, you can just cut delrin DUB crank spacers into a C shape and use those as well. I personally, would be wary of using a 3d printed or generic plastic compression ring, especially if they struggle to hold preload as the injection molded engineered nylons typically used for these parts are quite a bit stronger than can be produced with 3d printing. This is a pretty important part of the bike to get right and a loose headset is one fastest ways to kill a carbon frame. Hope this is helpful to someone and thanks for reading this novel of a post. EDIT: I should have added that a good number of the chinese integrated bars can either fit directly to an FSA split spacer or come with a transition spacer for the FSA system, so thats a good system to use from a compatibility with bars standpoint. The Deda system is more frame compatible. July 28, 2024, 11:09:34 AM |
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Serenade 4550 Wavy Wheelset SUB 1200g steel spokes 500USD
First impression of these wheels. I think these are a winner in terms of bang for your buck. I bought this wheelset from serenadebikes.net which is the brandname of 7-Tiger Bike Components. These wheels are clearly modelled after the Princeton Carbonworks 4550 Evolution wheels, but obviously a LOT more affordable and a lot less over the top in terms of decals and design. They're 529 USD with Pillar Wing20 spokes and 569 with Sapim CX-Rays (which are what the original wheels use). Personally, I've built and own wheels with both types of spokes and, I think they're pretty much the same and they're certainly indistinguishable when riding. The Pillars might be a touch less aero, being 0.2mm wider but I believe that's splitting hairs. The specs The standout feature obviously is the weight. As you can see, I've measured them to weigh 1190g. Frankly, I think that's absolutely bonkers for a 50mm deep clincher wheelset with steel spokes. Inner width is a more traditional 21.5mm hooked. Externally, I've measured them to be 29.75mm. My other wheelset has an internal width of 25mm and personally, I've come to the conclusion that I like a narrower internal rim width more because the tire cross section of a 28mm is rounder and steering and handling feels better. More like I'm used to from a tubular. Also, particularly when climbing out of the saddle, I really didn't like the feeling of a squishy front tire squirming underneath me with a 25mm internal rim. I'm talking the exact same tire pressure. About 60psi in the front for me. I think 21-23mm internal is the sweet spot for 28c-30c tires which is what I ride. It just feels better and more nimble to me. So are they aero? Obviously I need more riding time to at least assess whether there's a discernible difference in the data on my usual routes. These 28c Tufo tires blow up to 30.5mm on these rims. As you can see though, the rim at least visually appears to basically be exactly as wide as the tire. The ride I've been looking for that "zingy" kind of feeling of a superlight wheelset. IME it truly transforms the way that a bike feels and it's just plain fun to ride. My rim brake Chinarello that I use for crits has 60mm deep tubular wheels weighing just 1300g. Combined with cotton tubs that makes for a truly special ride feel. Aero and still crazy responsive when sprinting up sharp inclines. These wheels can recreate that kind of feeling in a truly magical way. I had a super aero wide wheelset on there before that weighs 1450g. But it just felt sluggish every time I needed to sprint up a hill. These just GO. And I don't feel like they lack inertia on the flats. There's no discernible lack of stiffness. The hubs are the now ubiquitous straight pull ratchet centerlock hubs with 36 tooth. They're DT Swiss compatible should you have to source different freehubs. This is my second wheelset by Serenade / 7-Tiger. I can wholeheartedly recommend them. I think they offer some of the best stuff there is in the 4-700USD price range. You can order via their website. However, I usually communicate per whatsapp with Marya (+86 180 2020 4229) This is my initial impression. I've only ridden these for a week now and I'll do an update when I've done a few thousand kilometres. January 28, 2025, 05:51:49 AM |
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Cargo Bike Frames
Hi All, Been seeing these types of bikes on the market these days, similar to the omnium ones: https://monopole.cc/en/product/cargo-bike I am wondering if anybody has leads on these style frames! Let me know what y'all think! February 04, 2025, 05:10:45 PM |
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Re: Is an Chinertown build really worth it?
... and I've been dropped on the hill climb by freak cyclists with watermelon calves and mid-level bikes. 50mi Gravel race last weekend, I placed well behind a guy on a fat tire bike with flat bars. When he passed my group up, someone nicknamed him Thighsenberg, because - well - his thighs were f*cking huge. I can ride any bike in the world, and I will always be passed by Thighsenberg (and others like him). February 10, 2025, 11:54:48 AM |
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Re: Better hold off on the Magene QED electronic groupset
Since the person that crashed was using a lightweight rotor, is there any information stated where they took a close look at his rotors to see if they were by chance glazed due to a combination of heat and some sort of surface contamination? I recently experienced on one of my rotors that it was glazed, and I had to use sandpaper and rough up the surfaces in order get the brake pads to stop the bike. In my case, the pads are resin, and were only 1/2 way worn. Kinda of spooky to pull the brake lever super hard without them bottoming out and have no stopping power. Some of this story reminds me of a problem I had with my Wheeltop EDS TX brake levers that for some unknown reason would lock up solid at the levers. After this happened 3 times, and I came very very close to crashing on a descent, I replaced them. Wheeltop had no interest in helping me to discover why this was happening. (I believe that the pistons in the lever housing jam somehow. The levers are still sitting in a parts bin. August 22, 2025, 03:59:56 PM |
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Re: Better hold off on the Magene QED electronic groupset
Magene sent a technician to inspect his bike while he was still in the hospital and bought him a wheelchair. Magene cited worn resin brake pads(they still had lots of braking material left) on lightweight rotors and the groupset not being installed by an authorized service center. Magene said once the brakes were bled and had new pads, the brakes worked fine. The rotor brand released testing showing that the resin pads work fine on their lightweight rotors with resin pads worn all the way down. Pads shouldn't fail in an on/off way. When the pad is worn off, the calipers should still squeeze the metal backing plate against the rotor and slow you down while squealing to warn you. There are videos of mechanics showing that the QED calipers don't grip the rotor when worn down completely, while SRAM, Shimano, and LTwoo calipers do. Perhaps calipers without enough travel + a poor DIY bleed + half worn resin pads + lightweight rotor = randomly losing your brakes? Video overview with a chinese speaker where I got this information from: August 22, 2025, 05:34:47 PM |
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Re: Better hold off on the Magene QED electronic groupset
This is some scary shit. The levers don't displace the fluid needed to actuate the brakes properly, or the design doesn't allow for pads to advance as they wear properly. I would heavily bet on the latter, but there could be many causes. One is simply that the bladder isn't flexible enough and requires more vacuum to maintain its displaced state than the the system can hold (e.g., the system is not well sealed compared to the bladder's static properties). In practice, all of these systems require some air to be present in the system, as otherwise, a perfect bladder material would be needed; however, you also don't want too much air. It's also possible that the system is consistently hard to bleed, but that seems unlikely. Further, the videos showing that the mechanics can easily replicate this in the stand suggest it's a design issue. This would be a recall if it were to happen in the US or EU. Perhaps Magene recognizes that they have some product design issues to address, which is why they decided to focus on China before entering those markets where regulators and consumers have historically been less forgiving. I hope the chinese cyclists continue to hold them accountable and that they roll out fixes, etc. Some of this story reminds me of a problem I had with my Wheeltop EDS TX brake levers that for some unknown reason would lock up solid at the levers. After this happened 3 times, and I came very very close to crashing on a descent, I replaced them. Wheeltop had no interest in helping me to discover why this was happening. (I believe that the pistons in the lever housing jam somehow. The levers are still sitting in a parts bin. Your type of failure, though no less scary, is more common. While it is also possible that the levers are physically jamming, I expect someone else to have observed this issue and replicated it, especially since you experienced the problem with both levers. The lack of return is likely due to the design of the wheel top system. Still, I wouldn't immediately consider this a design issue that needs a recall, as it could be an installation issue, bleeding, or even a case of using the wrong hydraulic fluid--conditions potentially which make the wheeltop design a poor one to avoid buying, but not a dangerous one. I guess what I am saying is that your wheeltop issue was bad, but this is next-level bad. August 22, 2025, 06:21:30 PM |
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Re: Better hold off on the Magene QED electronic groupset
From my experiences with magene products, I often find them unpolished (but dangerous like that is a first...), dogshit customer support or just with asshole proprietary designs. None of their stuff looks too good to me, it's baffling that they're seen as one of the more trustworthy chinese companies. I'm already avoiding their products but I had serious hope they would give us some much needed competition as Ltwoo is getting too comfortable too. Looks like real progress will take some more time. Marketing is powerful stuff. They have an actual US storefront and their product pages use proper English and not auto-translated gibberish. That's basically all you need to look credible. I've never had trouble with my LTWOO groupsets but keeping up with all their revisions and lack of support is tedious. I'm hoping Wheeltop keeps improving because on paper their groupsets are everything I'm looking for. August 24, 2025, 05:37:34 PM |
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Re: Better hold off on the Magene QED electronic groupset
So the root cause seems to be that the reservoir in the lever is too small and basically runs out of fluid if the pistons are pushed out enough. That's REALLY bad and completely unrelated to rotor type, weight of the rider or anything else. I'm pretty sure that an engineer figured that out in development, but a manager in turn ignored or downplayed the problem. After all, design iterations late in development are expensive...
August 28, 2025, 03:22:19 AM |
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Re: Better hold off on the Magene QED electronic groupset
Meaning the noise about lightweight rotors, heavy rider and long descent is just noise. Wouldn't this failure happen every time you wear the pads down? Imagine even if you have some worn out rotor on the edge of replacing 1.5-1.6mm thickness (1.8mm is new rotor thicknes), then you would lose braking even sooner on brake pads wear. For me this is completely on megene and unbelievably stupid engeniring mistake, there needs to be some safety faktor on every component especially on brakes, basically you need to be able to stop on absolutely destroyed pads and rotors no problem (like with shimano and sram) and absolutely nothing other is acceptable. The amount of absolutely destroyed brakepads to metal and cooked rotors I have seen in my bike shop is unbelievable, people just dont care about bikes that much and if I imagine that every one of those people would loose their brakes with very high chance of crashing is scary. It will be interesting to see how this will end up. August 28, 2025, 10:05:03 AM |
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