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Re: Yishun R086-D Aero Road
I can recommend the 70mm long version from Deda Elementi. Not available in the US though, IIRC. The end result is correct, a longer plug is helpful. The reason why isn't correct. It's sort of off topic, but it's worth thinking about in the name of safety of internal routing systems. I've been working on trying to make <2mm over bearing options possible (largely for my own use) and it's really hard because of what's involved and the potential risks of not getting it right. The majority of the bending forces are borne by the carbon tube. Carbon is exceptionally good at managing loads like that and the expander is fit via a very small amount of friction. It's not going to do a whole lot in terms of keeping that tube rigid and preventing bending. What it does do is that it prevents the carbon tube from shearing locally as it preloads the carbon tube. Historically a long expander wasn't as critical because the steerer made contact with the compression ring nearly 360 degrees and was held relatively tight against the upper bearing. Even if you lost preload and the bending got worse, the typical symptom was your steerer developing the "ring of death." This meant eventual failure but more often than not seems to be spotted before it led to an accident when riders checked on chronically loose headsets. The SL7 failures also start with the loss of headset preload. This causes three things to happen. First the bending moment increases exponentially, second the steerer is now facing local impacts against the compression spacer which in the SL7s case was a relatively small surface area part, third the steerer can get worn via movement against the metal spacer and because of the design of that spacer would rapidly develop the "ring of death." These three meant that fork failures happened much faster than on other bikes. The SL7 fix therefore needed to address all three: improved plug, extension hanging off the bottom to limit the effect of those impacts, and a metal ring to be a new wear surface and further distribute forces around the steerer This is less of a problem for other systems like the FSA ACR because their compression plugs use a different design that's heavier but less likely to lead to preload loss and their C ring has more contact area. Its even less of a problem for the current gen Deda DCR because it uses a nylon spacer that will wear the carbon less and it's designed to fit tightly to the steerer. It's also 15mm deep which has even more contact area. With all of these systems you should check them every few thousand miles or so even if you have never had any issues with preload to look for wear. If your headset can't hold preload, I would chuck it and replace it with either the FSA or Deda system that fits. TLDR: Headset preload is more important than ever. Don't ride with a loose headset. Using a high quality insert / expander will certainly help! October 14, 2023, 01:25:26 AM |
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Re: Hygge Aero Carbon Frame
Just received my frames this week and wanted to share my thoughts with you all. Got pretty much what I expected for the price, considering they came from China. No major design flaws that can't be addressed. Let's dive into the details! Positive: - The paintwork is really beautiful - The frames are super light (1063g in size 55/L) Negative: - The seatpost clamp is a pain. The hole of the middle wedge is too small and the screw prevents the wedge from moving sufficiently towards the seatpost. No matter how much torque you tighten it with, the force only works against the edge of the hole and not against the seatpost. (I'll do a separate post about that) - The handlebar is just one of the cheap generic ones from aliexpress. It feels extremely flexy, I'm not sure I trust this one. You can often find it branded as Kocevlo, but there are many other brandings too: https://fr.aliexpress.com/item/1005006028345937.html Strangely, their website shows a completely different cockpit and headset assembly: https://hygge-bikes.com/products/high-performance-integrated-road-handlebar - The headset sucks and both of my frames were missing the top plastic cone. The headset has a slight amount of play. This is by design as there is no such thing as a compression ring/cone that could hold the upper bearing inner ring and steerer tube tightly together (different post). - The frame and fork are very supple. I think they went to the limit, is this really still safe to ride? (I did a lateral stiffness test on the fork, it bends a lot -> different post). - Seat tube angle: 73 degrees is too small (too much backset) in size L. Combined with the huge setback of the post and a big saddle pull (13cm mark, close to the maximum), it's really a pain. I am in the most forward position and still 5mm behind my optimal position (I really hope that one day a 0 setback post for the generic FM236 frame will be released). - The front thru axle threads are only glued, other suppliers now show the fork with a replaceable insert https://fr.aliexpress.com/item/1005005982170845.html https://www.alibaba.com/product-detail/New-Product-FM236-Red-glossy-Hidden_1600862434667.html Neutral: - Headtube angle is quite slack and I was afraid of the bike being really sluggish, but in the end I found it sufficiently agile. - The chainstays are not wider than on other (disc-)bikes I've ridden. So no problem with heel clearance for me, although my heels are close due to my slight V-shape foot position. The build was quite easy, luckily on 12s Di2 I don't have any wires going to the STIs. 7.7kg (55/L) including pedals, bottle cages, Garmin mount, powermeter (heavy 105 11/34 cassette, not the lightest tires, ..) that's really good for an aero bike!! October 14, 2023, 12:32:27 PM |
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Re: Carbonda Gravel Carbon frame CFR707
I replaced the fender bold at the chainstay/BB junction with a flat head bolt to make it a little easier to get the wheel on and off. I designed a screw for 3D printing that fits flush with the frame: https://www.thingiverse.com/thing:6266960 October 15, 2023, 02:25:41 PM |
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Re: Yishun R086-D Aero Road
1000 mile / 1600 km Update I've been riding my new Giant Propel Advanced Pro for the past two weeks. So switching back to the Yishun really helps put perspective on the frame and it characteristics. Also I have been using the R086-D with a variety of wheels: Winspace Hyper D67, Elite Drive 65D, Yishun's own wheels, and Yoeleo C50 Pro. A mix between latex and TPU tubes. Negatives: -The upper bottle cage mount is too high. While it's easier to grab, it can make putting the bottle back tedious at times. It's probably less aero too and you may not be able to use an extra large bottle without hitting the top tube. -The gap between the down tube and front wheel. I can't imagine this section being aero since the sizable gap could lead to turbulent air and subsequent drag. Not sure how Yishun could resolve this while keeping the same stack and reach. Positives: -The frame is stiff and but not punishing. A $1500-worthy frame for sure and way more exciting to ride than my Yoeleo R12. No detectable power loss through the bottom bracket. Everything "just works" when the speeds get fast. The back end/rear triangle isn't as composed (over bad pavement) as my Propel/AllezSprint/T1500 but decent enough given the price. And superior to all my other sub-$1000 frames. -The geometry and design as a whole lends itself to be an awesome gran fondo bike. It's not as nimble as the aforementioned bikes but it makes up for it in control. Even if the R086-D design or geometry isn't for you, I have no reason to believe Yishun's other offerings won't have the same higher level of performance, fit and finish for the price. Pay very close attention to your bike fit and wheel/choice. Not surprising these two areas will dramatically determine who you feel about the frame. You can mitigate the stiffness with 23mm internal wheels with steel spokes. I need to reduce my fleet of aero bikes and the R086-D will probably be the reason I sell my Allez Sprint. October 17, 2023, 03:18:19 PM |
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Re: Spcycle New Mold G056 Carbon Gravel Frame
I’m doing a build with this frame and have a possible issue with the T47 BB being very tight. I’ve never worked with this style, so I’m not sure what to expect. It gets hand tight after a couple threads and then really starts to get snug. The threads seem clean and it doesn’t seem to be cross threaded. Both sides are the same. I don’t want to get too rough with it and bind or break something. Any ideas?I've run into this problem several times. These days, every frame I purchase from Alixpress, I wash out the bottom bracket threads using soapy water and a stiff nylon brush. Then I blow-dry the threads with a compressed air nozzle. All it takes is one small piece of metal in the threads to start the binding/cross-threading of a thread. I spent about 2 hours one time on a threaded bottom bracket thread with a magnifying glass and a fine metal pick carefully restoring a thread where I had messed up the thread due to a fine metal filing that became embedded in the bottom bracket thread. The filing messed up the crest and was stuck in the thread root. October 18, 2023, 01:41:04 PM |
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Re: Wiggle/Chain Reaction Filing For Bankruptcy? - Sale On Everything
Serves them right for refusing to sell Shimano and SRAM components to the US. You're right, they deserve to go bankrupt for honouring their agreement with sram and shimano. October 20, 2023, 11:39:10 PM |
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Miracle / MIRA FS822
My Miracle FS822 arrived this week. I'm excited - it has taken me 6 months to choose, order, cancel, re-choose and re-order the frame for this next build! Interested to know if anyone is using or considering this frame - there's very little about them on the forum here. It is size L of this frame painted gloss black: http://mira-factory.com/Product/detail/id/43.html. Frame was chosen because Miracle have been around for a long time, good geometry, good price, good communication. It's also nice to try something a little different. I think this new breed of 120mm cross country frames is one of the most interesting MTB developments at the moment, and I can't wait to try it out. This is my third Chinese frame build. Others are Airwolf YFM026 hardtail (2.5 years old, no problems); and a Carbonda 1001 (my son's. 18 months old. Gets hammered. Parts frequently break but no problems with frame). There are a few reasons for this build: 1. A reward to myself for hitting 3.5w/kg when training for this season (although racing didn't happen because of life!). 2. To take over from my old Kona Hei Hei race bike that I really miss! 3. Something that I can use on less extreme trails, but that can handle them when needed. This should be great for marathon races in BC, Canada and for all day rides up in the alpine! 4. To potentially take over from the Airwolf, which I will either sell or convert to singlespeed and fully rigid. 5. I love selecting and building these bikes. I'm not quite ready to build the FS822 yet - it arrived quicker than expected! This week I have unpacked it, designed decals and ordered wrap. Build will use: - Fox 34 Performance Elite 120. Removed from Airwolf and fully serviced with new decals from Slik - Fox Float SL - Dartmoor Tomcat rims. DT240 front hub and Shimano XTR rear with Sapim Laser spokes. Not yet built - Bontrager Raceshop Limited carbon bar/stem combo, TransX 150mm dropper - Magura MT5s - Drivetrain from the Airwolf: Deore 12sp with XT shifter and X0 carbon crank / chinese power meter. Impressions so far: - Seller was Sally. She has been excellent at answering my detailed and sometimes stupid questions and always responded quickly on Whatsapp. Recommended. - Frame was in stock. Paint took just over a week. Frame was shipped immediately by UPS and arrived in Canada in 5 days. Frame very well packed. - I have not checked frame bearings etc yet but first impressions are that this is my best frame yet. Very clean inside the frame. Paint is excellent (1 small blemish that has been touched up on ICSG mount). Seatpost fitted very smoothly. I have high hopes for this frame from on experience so far. I'll update the thread as I progress and if / when I run into any problems. Poor pics taken so far are attached! October 27, 2023, 06:01:55 PM |
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Re: japjoe7 Carbonda FM1001 build thread
Wheel time October 29, 2023, 06:32:07 PM |
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Re: Carbonda Cfr 1056
Finally I fixed the rear brake problem by using a 140 disc without adapter. This is my setup:
October 31, 2023, 07:01:12 AM |
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Re: Best way to Chinertown road disc groupsets? :)
If you're sticking to Shimano, Sensah now offers hydraulic Shimano compatible 11 speed shifters now. Apparently 12 speed shifters will follow soon. Also I go back and forth between my Sensah and Shimano equipped drop bar bikes no problem. Though I only use Shimano front/rear derailleurs and chains (I don't touch aftermarket chains), but I have no problem using AliEx cranksets which I think are quite mature at this point. I do think Shimano cassettes are still better at shifting though, but I am currently using a lightweight SRoad/Spedao cassette on one of my road bikes. I'm also using Onirii disc rotors on my road bikes and Shimano Ice-Tech rotors on my gravel bike. There's lots of room for mixing-n-matching, I actually find it more fun having a customized setup. I get bored looking at the same LBS bought bikes with no personality. November 03, 2023, 01:03:33 PM |
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