Questions tagged [frames]
Bicycle frame construction, selection, maintenance, and repair.
955 questions
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Step Over (high bar) vs Step Into
What's the pro / con list for a step over vs step into bike?
As far as I can tell the step into bikes are just easier to get on without any disadvantages. Please correct me - does this design have ...
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Can someone please help to see if FR111 is a real serial number for a 1979 Robinson bmx [duplicate]
I’m trying to figure out if this serial number on a 1979 Robinson is legit it reads FR111 thats it. Can someone please help. Thank you.
3
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Steel Frame Broke (Top Tube Just Behind Head Tube)
I have a 1992 Trek 950 Mountain Bike. I've converted it into a cargo bike with racks and baskets; I ride it day or night, rain or shine. I have about 50,000 miles on it. Over the past month or so ...
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Weird bumps on my Carbon frame fork
I recently noticed some unusual bumps on the fork of my carbon bike. The paint is intact, and there are no visible cracks or signs of damage. However, the bumps seem to follow the pattern of the ...
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Abrasion on the seat stay down to the carbon - any impact on frame stability?
Hello you wise people,
I have a road bike frame that has some abrasion, most likely due to the bike rack. No impact. From the touch I can feel that it goes deeper than just surface level. I believe it ...
- 61
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Rusted steel rivet nut on aluminum frame causing frame to corrode
I have an aluminum-framed hybrid which has rivet nuts set in it for mounting racks and fenders. I am pretty sure these are steel rivet nuts because they seem to be rusting and causing corrosion on the ...
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Is there a quantitative method for measuring vibration damping and frame comfort?
Discussions about frame strength or tire rolling resistance can be quantitative: occasionally someone will provide objective evaluations.
But one topic that resists quantifying is comfort. Various ...
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Can I install a screw all the way through these threaded fork crown holes?
I've got a ~2006 Trek 520 and the fork crown area has a threaded hole on both the front and back as pictured. Note that this bike is set up with V-brakes and the hole is not used for a front brake. ...
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How to fix a bottom bracket shell that has been cut from outside?
I have a 27.5" MTB which has a damaged bottom bracket shell. When I install the bottom bracket into the shell, it does not stay in the center of the shell. It leans towards the bottom of the ...
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Bmx bike stamp on dropouts
What kind of BMX bike has an S stamped on the back drop outs? I think it is a Sunday Bike Co. bike, but I can't be for sure.
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Accidentally punctured through aluminum frame with a screw tip - still safe? Repairable?
I went to tighten up my rear rack and realized that it was actually a screw not a bolt holding one of the arms on my rear bike to my frame. Apparently I stupidly used a screw that's longer than the ...
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My rear dropout notch is 12 mm (roughly 1/2"), am I correct in thinking a 3000 watt rear hub motor axle won't fit?
The bike is a Seattle Micargi stretch
The rear dropout width is roughly 180mm and the rear axle dropout notch was widened to 12-13 mm to accept a thru axle rim with a 12 mm axle. With the notch being ...
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Trouble finding frame hanger Daymak to Shimano RD-R3000
Having a really tough time finding the following part:
Frame hanger
3/4inch 1.9mm width screw holes.
Frame # DMK17PR000000004
Derailer # RD-R3000
I've ordered a few, but there is always something ...
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What is the purpose of the top tube on bicycles?
What is the purpose of the top tube on bicycles? To neuter guys? My brother crunched his balls so hard on his bike, poor guy.
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Scratch or crack in alloy headtube?
I was going over my bike in preparation for the season, and noticed these marks on both sides of the bottom side of head tube, near the weld to the down tube. I can't find any other marks on the bike ...
- 31
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Identify year of Kona
I have a Kona Process 134 DL. The serial number is H5AH31229 and I am trying to determine the year. There is also a sticker EN14766. And stamped 4, then under XL, then under T. Can anyone help?
...
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Help identifying this Freeagent bike?
so I’m considering the purchase of this bike but all the information about it provided is that it is a Freeagent bike. There are asking $150 and depending on the model/year that may or may not be a ...
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Help identify early 90s Chro-Moly MTB
I have this Chro-Moly bike I bought in the early 90s in Chile branded as Oxford, but I believe the frame is an import. One mechanic said it is japanese, another that it's italian. The rear part of ...
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2012 Cervelo R3 downtube cable stop - replacement part
I need two replacement downtube cable stops for a 2012 Cervelo R3. Does anyone know where I can get them? I found 1 for $50 which is outrageous.
Any advice or leads is appreciated!
Greg
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Is it correct that the bottom bracket shell thread does not go all the way around?
On the inside of the bottom bracket shell, the thread does not go all the way around. At the places where the tubes are welded (or attached) into the bottom bracket shell, there are holes in the ...
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Question regarding serial number
Can anyone help me decipher this serial number on my DB? ACS6J02432
I am trying to figure out the exact year and model of this 24" BMX
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Heavy corrosion of the bottom bracket shell, but rest of the frame is fine
I have a Btwin MyBike cycle, which is now 8 years old. The frame is an steel alloy.
I want to replace the bottom bracket, chrank shafts & chain ring.
The BB was very difficult to remove, used a ...
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rear rack > frame compatibility (child seat)
I have a Topeak BabySeat II MTX 2.0 Rear Rack that is supposed to mount into threaded holes in the frame. However, my old road bike does not have these holes, and instead has eyelets welded to the ...
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Help me identify the model of this Cannondale frame
I tried everything, saw many catalogues and also tried with the serial numbers but still nothing.
this is the serial code I think. From what I can read I see it's BNRB300131 and the other code is ...
- 21
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635
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Reynolds double butted 531C top tube rusted, worth repair or not?
Pictures show underneath of top tube. Tube made of 25.4 mm (1 in) Reynolds 531C steel. Rusted through, cleaned a little with file, and most material is still there. Is it worth repairing? Carbon fibre ...
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Another question regarding the specific size of stepped ferrules
I have a frame with in total 5 brazed-on cable stop with 5 mm inner diameter, on at the chain stay and 4 at the bottom bracket, and I'm using 4.5 mm outer diameter shifing cable housing. The standard ...
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Can anyone tell me what frame this is please?
Can anyone tell me what frame I have here? It has RockShox forks and removable rear dropouts.
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What Gary fisher model is this? [duplicate]
Repainted so pictures won’t help. Sn looks like T8T-1123 second row C44EMO15. 24 speed aluminum about 16.5 frame with Alivio derailleur. Original color was black with yellow trim.
Thanks for any ...
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Carbon fiber frame and dropout alignment
I have tried searching for these and failed to find answers.
Is there any tool available for facing a rear dropout to make the two parallel? The dropout alignment tools show that they are not aligned....
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How does the frame geometry of a cyclocross bike affect its performance in off-road conditions?
The frame geometry of cyclocross bikes aims to offer a responsive and agile feel while providing stability and control over mixed surfaces. It allows riders to handle the demands of cyclocross racing, ...
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Bent Marin team issue steel derailleur hanger. Can I salvage this incredible frame? What's next step?
I found a marin team issue on a local marketplace. The frame is in good shape it seems and I have many m900 parts from the time so I'd love to re-build completely.
The main issue so far is the ...
- 587
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Pinarello FP3 30HM12K real or not? [closed]
https://link.marktplaats.nl/m2032857289
Is this Pinarello FP3 real or fake?
Serial number: 30HM12K
Who explain to me. See the comments under please.
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Wear marks on seat stay from fender/mudguard. Problem?
Mudguards have worn away where they contact the seat stay on carbon frame. A little deep, wondering if cosmetic or more serious. The one on the right stay doesn't look as deep but you can see 3 ...
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I need help identifying this "Mystery Bike" (could possibly be a real ferrari?)
New UPDATES below!!!
Good day to everyone,
So i have this really old bike.
I don't know its brand and model. The paint is still stock, and it has a Ferrari sticker with the name "Michael ...
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Carbon frame damaged? [duplicate]
I had a crash a couple of weeks ago with my BH Quartz. The front wheel got caught in a crack in the road, I heard a crack and I fell on the side. I was worried that the frame cracked, but couldn't ...
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On WSD bicycle shouldn't the seat tube be longer and at a shallower angle?
I bought a WSD ("Women specify design") bicycle for my wife which was delivered in a box.
After putting it together I took it for a ride to test it and I realised two things.
The seat tube ...
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What is the name of bike fork spacer for shipping a bike frame?
I am trying to pack my bike for an plane ride, and while packing I wanted to know what is the name of the spacer that needs to replace the wheel(s) between the fork dropouts to prevent frame ...
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Are these scratches in my aluminum frame structural or purely cosmetic?
My aluminum bike (Cannondale Adventure 1) was scratched on the welds connecting the seat tube and seat stays, and I was wondering if the damage is purely cosmetic, or if there is any structural damage....
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Is this a serious paint defect?
I am about to receive a bike and the shop has informed me of the following (cosmetic, they claim) paint defect:
Since I don't have a lot of experience, is this something that might chip off? Or is ...
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Cassette Compatibility Issues [closed]
Because I sit at home playing games in doodle jump too much, I decided to buy a bicycle to exercise.
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Vintage 531 frame. Identify original make?
I rescued this bike from the tip a couple of years back and rebuilt it (in the UK). I am curious to know what the original make might be? The original frame had been badly repainted so no makers name ...
- 353
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Another carbon damage assessment?
Mostly cosmetic? Chip is located on the bottom of the top tube. Did it go through a layer of carbon, or is that just paint/resin? Dime sized. This is an enduro mtb frame, so assuming it's built ...
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What model is this Dyno? Serial number makes it 1995 Nitro? VFR?
All stamped Dyno, white chainwheel, forks, stem, and bars. Cant find another like it, wondering if parts may have been swapped out at some point because I cant find this colorway anywhere, the ...
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Challenge Seiran luggage rack image or blueprint
Years ago, I bought a Challenge Seiran. At the time, I didn't bother buying the luggage rack attachment. Not the one attached behind the seat but the one going under it.
For those who don't know, it ...
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What size of inner tube fits a 650x47b tire?
What size of inner tube fits a 650x47b tire?
It's gravel bike. The tire states it's tubeless ready but there's a tube in it currently.
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Is it possible to prove that applied forces to a top tube are worse than a seatpost when using a repair stand clamp?
This stems from the idea that you should use a bike stand clamp on a seatpost, if you can, for carbon fiber (CF) bike frames. Hopefully, this would avoid the cracking of a CF bike frame.
In order to ...
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Need help identifying this logo on 2016 bmx
I was looking for a bit of help identifying this insignia on this 2016 bmx I'm restoring. Any help would be fantastic
4
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Which geometry specifications determine the seating position of an MTB?
MTB manufacturers release geometry data for their bikes. If I want to know if a bike has a more upright or stretched position, which geometry data do I have to compare?
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Aluminium frame alterations
I know it is possible to make almost any type of frame alteration to a steel frame. But what about aluminium?
I would like to know if anyone has a first-hand experience in adding braze-ons, and doing ...
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