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Serpah FM199 Drop Bar MTB Build
I wanted an aggressive gravel bike that's able to fit MTB tires. Trying to copy a Salsa Cutthroat with a Chiner frame. I basically wanted ~70mm BB drop, clearance for 29x2.25, chainring clearance for 36t+, and modern XC geometry (100mm fork geo, ~69 deg headtube, etc). I usually ride large MTB's (I'm 5'10.5") so I ordered a medium FM199 frame from Serpah on Aliexpress. It arrived in 9 days from ordering and was packaged very well! -Serpah FM199 Chinese Carbon 29er MTB Frame -SRAM Rival HRD 1x w/ 38t and 10-42 -Teravail Sparwood Tires on ARC27's laced to Novatec hubs (my first wheel build!) -Niner Boost RDO Fork -Tranzx Dropper actuated with left shift lever -Ritchey VentureMax bars The main setback on the build was routing the rear derailleur cable. This frame is intended to run bare cable through the frame, but I like to run full housing so I drilled through the frame fittings. The DS chainstay is THIN inside, I had to grease up the housing and use a bit of force to get the housing through. With Jagwire 1.1mm cable there's no issue with stiction. Other than that the build was super straight forward, the BB was solid and the PF BB went in no problem, no creaking yet! Headset area was solid, the rest of the cable routing was easy, everything else went together in one night. This frame is weird that the rear caliper is set up flat mount, but they include an adapter. Luckily I'm running a road groupset so I actually am running flat mount in the rear and post mount in the front. Since there's only clearance for 29x2.3 tires and it's boost spacing, the DS chainstay runs parallel to the centerline a ways past the chainring, I'm sure I could fit a 40t or 42t no problem. It weighs 21.9 lbs as it sits in the pictures. I also have carbon road wheels that will get the weight down to 20.5 or so. I could drop another pound or so off the gravel weight if I went carbon with some lighter spokes, but I'm pretty happy as is. The wheels are 1840g without tape or valves. I found a nice gravel two-track trail that leads into a tight single-track trail and then leads to a long dirt road, this bike was perfect for that! I want to get it out on some longer single-track trails to see how it does.   
October 02, 2019, 11:19:15 AM |
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Re: ZTTO MTB M1 Boost hubs 28H 54T Ratchet
I've got some built up with i25 SpeedSafe Ultralight rims. Final weight of 1340g without tape or valves. I've been happy with the engagement and sound over about 250 miles. I'll give an update when they have a ton of miles on them or if anything happens. Not much to comment on other than high perceived quality and machining work.
September 21, 2020, 01:22:09 PM |
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Re: Help me doublecheck my nooby first enduro build FM10
I hate to say this on the Chinertown forum, but I think you'd be better off with a used lowish end FS bike for $1500 or a nice used hardtail for that much. Everything you have is the cheapest of the cheap.
October 15, 2020, 03:30:46 PM |
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Re: Carbonda fm936 Thoughts
Hi Quentin, thanks for all those graphics and don't want to deviate the thread, but even when the saddle/handlebar distance is the same, the pedaling position it is not. In this example you are much more over the BB which I don't want to change from my actual bike as I train on three different bikes and have it dialed in terms of power and comfort, this is why I think it would be easier for me to get that position on a M frame. I would like to keep the same saddle to BB height/offset and distance to the handlebar. Maybe it would not be possible on a L as the reach is much longer.Just curious, what are your other 2 bikes? Here's some potential perspective. Take the example that you get a bike fit on a road bike, the fit is done on a stationary trainer. There will be an ideal saddle height, set back, and tilt to maximize power and minimize discomfort. This is important because you are always seated in the same position and grades are not as steep as MTB trails. For an MTB, the "perfect" pedal position is less important in general because you're constantly moving around and shifting your weight, therefore the best position is a balance between good fit and weight balance. Now what if you redid your bike fit, but you lifted the front tire up enough to match a 5 or 10% grade? You'd push the saddle forward to compensate, since the STA gets slacker. It's true that when you go back to flat ground, it's a compromised position, but if your trails are constant up and down, does that matter? Take this with a grain of salt, the new style geometry isn't for everyone. I'd bet that a bike with a 69 deg HTA and 73 deg STA would be faster on flatter XC trails than the newer bikes with 66 deg HTA and 76 deg STA, especially tight courses. But if that's what your trails are like and you want the perfect pedaling position on flat ground, then this likely isn't the bike for you. If you downsize and push the saddle back, you'll just end up with a rearward weight balance, it'll be hard to weight the front tire in corners and won't feel right. The slack HTA, steep STA, long reach, and long wheelbase all play together. November 05, 2020, 08:55:34 PM |
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Re: Affordable forks with 36mm stanchions
I ordered a Markhor from Anto Bike Store on Ali 2 years ago and as far as I could tell it was legit, it's still going strong.
March 22, 2021, 11:52:04 AM |
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Re: Affordable forks with 36mm stanchions
How do you find the fork? Thinking of buying one for an xc buildCan't comment on that, I put it on a friends bike. He's given good feedback, but it's his first air fork so doesn't have anything quality to compare to. He just dropped the bike off for yearly service yesterday, so I'm curious to pull the lowers and check it out. March 22, 2021, 12:45:19 PM |
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Re: LCFS911 full suspension
Just did the final shakedown. Very happy with the feel and power delivery.I've got this frame now! 1950detroit sold me the frame, fork, shock, handlebars, stem (I swapped to 80mm Syncros stem instead of his 120mm stem), seatpost, and saddle. I had most of the parts laying around, just had to buy a crank, chain, and a few little parts. Specs: Fox shock (Trek Top Fuel Takeoff) SRAM XO GXP crankset (started it's life as a 2x, swapped on a 32t ring) 11-speed GX derailleur, XX1 shifter, X01 cassette, XX1 chain Formula Cura 2 brakes Amazon $20 disc rotors Speedsafe rims, ZTTO 54t hubs, Pillar Wing 20 spokes, Sapim brass spokes (I built them) Vittoria Mezcal XC 29x2.25 (I'm curious to try a Barzo front) Following parts from Scott Spark takeoff: Rockshox Sid 100mm fork Boost Syncros Carbon Seatpost, Bars, stem, saddle, grips Bontrager comp pedals Build ended up at 23.2 lbs with pedals, and 23.6 with dual bottle cage. I 3d printed the bracket to hold both cages at the perfect angle, could maybe make an aluminum version that's lighter, but I'm not worried about it, the bracket itself is around 100g and the ABS part seems plenty strong. First ride was a success, the bike was really fast, it's about 1 lb lighter than my hardtail so having a lighter bike with the sting taken off the rear end was nice. I only felt any noticeable bob when standing and pedaling hard, and it's nothing major. The noise I heard was the topping out of the DPS shock, but I think I need to add rebound damping and soften the air spring. I added McMaster neoprene foam around the cables so those are silent, which is really nice! I'm hoping this bike will be the perfect XC and long distance bike. My favorite ride is a 57 miler with 18 miles of very rooty old-school singletrack, 21 miles of flow trail, and the rest is gravel to get in between. My hardtail makes my joints ache by the end and my trail bike is just so heavy. The goal of this bike is to cut the difference. I think my biggest surprise was how nimble the bike was. My hardtail is a Transition Vanquish, which is 67 HTA (which should match the 911 HTA once sagged), 75 STA, short chainstays, but the LCFS911 feels SO much more nimble around tight turns.  
March 28, 2021, 11:01:42 AM |
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Re: Evil Chamois Hagar
http://chinertown.com/index.php/topic,2837.msg20146.html#msg20146 I did what you mentioned, 29er frame/fork with drop bars. To be honest I don't ride it enough to give a good review on the setup, but that's not because I don't like the bike, I just ride trails 99% of the time that I don't want to ride rigid. Thought I'd ride gravel more than I do. April 28, 2021, 03:10:15 PM |
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Re: Full suspension build
https://www.mtbdirect.com.au/how-to-measure-the-shock-and-hardware-size-on-a-mountain-bike There's a writeup and picture in this article about trunnion mounts. Standard shocks use an eyelet at either end of the shock. These eyelets require purchasing hardware to fit the frame on both sides. A trunnion mount is basically two threaded holes on either side of the shock body. There will be bearings in the frame or linkage, and frames will come with the bolts that go through them, so you will only need to purchase hardware for the one eyelet mount on the other side of the trunnion mount. I believe the FM936, ICAN S3, and LCFS911 all use trunnion shocks. May 27, 2021, 10:20:55 AM |
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Re: Carbonda fm936 Thoughts
I've only tried that mount on a GG Trail Pistol with the bottle cages hanging down from the top tube, haven't tried with a bike on the downtube. It was wide enough that my knees were constantly hitting the bottles. It also looks real silly, but some may not care about that. I think the best solution is using a mount to stuff two bottles in the triangle. I used Lyne Components for inspiration (because I wouldn't pay this much for just a mount) https://www.on-lynecomponents.com/collections/the-holy-rail/products/holy-rail-dual-cage-kit and I 3D printed my own bracket. It's about 100g if I remember right, super stiff, and I can design it fit the frame perfectly. Here's a picture mounted on my LCFS911, not too easy to see in that picture but it shows the concept. The mount shifts the forward bottle cage up one bolt hole, so if you mount a cage on the FM936 using just the top hole and it fits, and then if you can hold a bottle between that and the shock, I should be able to make a mount that will fit. I've also got a 1:1 PDF of the mount that you could cut out and see if it fits without modification.
June 03, 2021, 07:19:02 AM |
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