convert old bike to disc brake 

You converted a safe bike into an unsafe bike. The frame and fork pipes you soldered your caliper supports on, were NOT designed to handle the force the disc calipers will put on them ! It's pure physics. The braking torque applied on the wheel (when you brake) is about the same (disc brakes don't stop the bike faster than new & well tuned rim brakes). Torque = Force x (distance from the center of the wheel). But the disc brake pads apply the force WAY closer to the center of the wheel (on the small diameter disc), than rim brakes (on the big diameter rim). So at the same torque, the force applied by a disc brake pad on the frame, must be WAY higher than the force applied by a rim brake on the frame. Also multiply that big force by two, because a disc brake applies the force only on one side of the frame (a rim brake has brake pads on both sides of the wheel, so the braking force will be applied on both frame bars on both sides of the wheel). The same thing for the front brake. A fork failing while hard braking is really dangerous. My advice: If you can, revert quickly to rim brakes. If you can't, cut that bike in pieces, and throw it in garbage. Don't let your kid ride it. It's dangerous. I like how you sing, and how you love your kid, that's why I spent my time to write all this.

I'm a retired aerospace stress analyst that analyzed every type of welded tube structure on aircraft. I also am a licenced faa certified airframe mechanic. Just by observation of this welded bracket conversion, I'd say it is a well done installation and the loads that are going into the brackets by the calipers during stops are directly into the centerline if the tubing with no offset bending moments. Therefore the backup structural tubes are more than adequate to react any braking loads over the 4" of distributed bracket loads. Since the rear brakes react about 30/49% of the entire required braking force, the bending load into the rear down tube at the rear bracket attach location would be less than 200 pounds by rough calculation distributed over the 4" bracket. Steel bike frames are typically made from chrome moly steel which have about 125 ksi FTU and about 100 ksi outside of the HAZ of a weld when annealed. The Fty an = about 60 ksi. The bending moment from worse case 300 lb at this location in the tube with fixed ends would be PL/12 = 300x 15"/12 = 375 in-lb. Stress = mc/I, where I for 1/2" tube with .050 wall = about 0.002 in to the forth. So stress= 375 x .25 / I.002 = 46,875 psi. Factor of safety = 60/47-1 = +0.28. yield. This conversion is good. The front forks have almost twice the bending inertia with 3 times the load of the rear bracket. Therefore good by inspection. This is your Lockheed style stress calculation factor of safety. So please don't say this is an unsafe conversion. If u do, plz show your calculations that prove other wise.

The song at the end felt kinda like the end of the world song of the people that's leftover and just happy to be alive and thankful

What I love about this post is the practical simplicity of it! Here I am, seeking to rent time on a cnc machine, making out measurements on a computer and considering buying engineering tools, all because *I love my bike* and I thought the switching to disc brake requirements was totally both unfair and unnecessary to a *loyal and dear old friend/my bike* ! Willing to spend $3000 on my ❤ than $1000 for a new one! 😀

Marahi kepingin . . aku .isih duwe frame Alpine STAR edisi tahun 1990 . . Kesuwun MasBro , sampeyan kreatip tenan

Magnífico trabajo. Eres un artista. Yo para dejar el trabajo bien fino aseguraría la camisa del freno delantero a la horquilla y quedaría mejor aún.

I pray who ever reads this becomes successful in life...

Nice procedure.... really liked this and you inspired me to do this on my old Trek,

Absolutely the best bicycle disc brake conversion video hands down .... Great job ! Ill be using the same exact technology for my motorized mountain bike ... Thanks

Mantap mantap mantap mas bro, jadi inspirasi buat saya nge restorasi sepeda federal jadul saya... Salam gowes dari Bandung mas bro....👍👍👍👍👍

Really enjoyed your video. Especially the part of you riding with your boy. And the music was great! Thanks for sharing

This is what I need to see today... very helpful and just grounded me. God bless you guys and Merry Christmas. Careful Lil Man😜

Super great thinking outside of the box! Much respect for finding a solution! Should clean metal before welding!

amazing. subscribed. i have two bicycles that have been converted to ebikes - your video has answered my questions

That welding on those mounts is the finest best ever welding ive seen, absolutely amazing, could hold ten ton of force no trouble at all

Cool - I need to put a front brake on a 1970's cruiser conversion to ebike and it only had 1 brake, this solves my problem. Nice production loved the chickens and the song at end.

Suwun tenan mas . . .wis entok elmu dikekke lagu maning . . uuenak tenan mas . . matur nuwun . . .siiip

Gara-gara sampean orang bule pada debat,keren modifnya om....

As far as any engineering dangers, I will simply weld a buttress from the chain stay to the set stay for *support* . Thanks, great video! 😀👍

Man! You are Great! Enjoy life. You deserve it. Regards from Greece.

your videos are great and gave me an idea for a new bike from the old frame. your ideas are cool.

Wow...Thank you so very much for this excellent conversion information. Indebted to you. I'm going to do the same.

This put a big smile on my face....well done.

I'm an Italian to English interpreter and I can tell you that those welds are OK, if they do happen to break during use the solution is easy, just weld them again.

At first the chickens were distracting but they grow on you . Very soothing song to wrap things up. Nice video.

Awesome job, dude. No more cooking your rims on long downhills or chewing out your expensive and inceasingly hard to replace caliper rims 👍

Thanks for this! Life is great, isn't it?

Outstanding job! I also changed my fork and hub and installed a disk brake. This is a great idea! I can solder, but I've never welded before.

Nice conversion, my frame is aluminum so I would wire weld (MIG) mine but the process is identical. I might give it a go. Thanks

Love the chickens squawking continuously in the background

Que buena onda tus videos yo cuando hera niño mi papa me dio una vici igual a esa pero sin frenos de disco ovio jajaja y anduve igual que ese niño con una sonrisa de oreja a oreja muy buenos tus videos siga así 👌👏👏👏👏👍🙏 saludos y salud desde Tepic nayarit México

Excelente tutorial, rajin. Muchas gracias.

Good job makes your heart sing !!

Great video, and your work is excellent!

Padahal ono ragum, tapi ngebor e nganggo tang diidak, jos tenan😂

Best conversion video ever!

bangsaaat dancuuuuuuk !!! aku seneng video iki pooool!!!!!! Suara pitik dan closing pancen toooop!!! 🥰🥰🥰🥰

very good job, well done. Hi from Belarus!!

Great build. You may use some cable ties to secure those loose wires. Nevertheless, good job. Mantap pak rajin 👍

Nothing brings more satisfaction than giving new life to old things. Well done rajin!

Mis respetos maestro 😊👏👏 grasias por tus conocimientos

Haha! That's they way I've done my STEEL FRAME brake conversions! I used to use them eyelets and screwed them on the rear triangle. Works awesome too! 🤙🤙 Can't beat the $29.99 brake kit. I love them components. They are just as good as shimano..😊

Just by observing at the welded part , i barely consider the finishing quite impressive.. this man has proof he is competent n has completed his tasks very well... My thought maybe he was somekind like welder or foreman who experienced working offshore longtime ago...

I really enjoyed the song near the end. Very peaceful.

My respect for you my bro.. God blessed 🙏😉😉

I love this vieo. I'm in love withe the song at the end, it takes me to .. i dont where. But it's a good place !

Me encanto ver el procedimiento del trabajo, y me gusto ver otra idea para mi bici por lo del cambio de velocidades ya que lo tengo con la rueda y no como la tuya, voy a ver si puedo hacerlo

me encanto el video... y mas aun el final con la musicaaa felizitaciones

Sing komen wong luar tok 👍👍👍😁😁😁 dasare jenius njenengan pak....

I remember the days when I used to ride a bike way bigger than my size , just like the kid at the end , those were good days

That ukulele playing was lit!

Konten yang mendunia kang.. Yg komen bule semua.. 👏👏👏👏👍👍👍

Q buen final!!!! !!! Saludos desde argentina!!

Tu és um GÊNIO .

😀😁😂 exelente trabajo amigo todo un artesano de las bicis

Simple but good work. And the singing is wonderful :))

Estaba buscando un video como este desde tiempo gracias

very impressive and looks great works perfect.

Ajiiiip...gowes ngga harus mahal ya om...yg penting bisa bikin kita sehat..

Apik mas garapan mu, mugo makin sukses mas 😆👍

Keren Om, bisa ngerjain sendiri 👍

Mantab,banyak pujian dr orang luar krn simple dan tepat guna.

Good! You are best mechanic, rider boy best, singer the best!

Mantaap bang, sangat bermanfaat.. Salam dari indonesia🇮🇩

Класс:))) малый на дискачах самый крутой на районе

buen trabajo si te quedo bien nomas que aplicando soldadura destiemplas el cuadro y lo haces fragil y se puede romper de ahi donde lo soldadte

apik tenan .....!!! sing mbarang ikut ngetop nih....

Keren om...yg komen banyak orang luar negri.....dan mereka terinspirasi dari orang indonesia....ga nyangka banget....

I really liked that part where the rooster said: errr er errr errrrrrrrr Good stuff very interesting 😂

Keren om, sangat kreatif dalam pengambilan video ada pengamen juga jd sangat menggambarkan susana desa yg ngangenin, salam dari Semarang om

Cool, good job. I like it !

Saludos desde Ecuadoer!! work good!!

Fantastic job, mate.

Súper vídeo me encanto tu idea

Wah!! You are fantastic...👏👏. No Parktools here...o wait! maybe it was the welding equipment 😂😂

Best video ever. Very entertaining.

Post more songs! That was awesome :)

Felicidades amigo buen video , saludos desde Perú🇵🇪

What did you use for your fork? 31mm or the 22mm one

Chanel keren, sing komen wong luar kabeh😁👌🏻

Hi mate! Just want to ask. How much did it cost for everything, except for the frame and the fork? Thanks mate! Nice video, btw.

Mantab, kreatif teruss tanpa batas manfaatkan apa yg ada

Nice work i like this idea you so very geneus

super cool convert! I just have a question about the welding part, i dont know anythig about building bikes or welding, but could the heat from the welding affect other parts of the frame? , if it could affect the frame, is it possible to prevent it with like covering the frame with some wet ice cold towel or something?

Kualitas video mantul om, kirain dari luar loh, eh kok boso jowo ngomonge, mantul pokok.e om

Muito bom. Quero converter à minha. 👍🏼

Exelente aporte Gracias por compartir Saludos

ono seng nyanyi lagune didi kempot. ambyar...tenan.

love the song i remember my childhood memories

Good job...salam dari minioners tangerang

Its perfect man so awesome we can just do it at home

Ótimo trabalho, vamos ver se o quadro aguenta a torção do freio sem quebrar.

Nice work I see quick and easy no messing around , same way I would do it , although I would add a brace in the rear triangle and maybe something more for the fork if I feel it needed it.

Excellent! 🌟🙌🏼

4:20 u should do gas welding for better pattern👍

Hasil.e rapih, mantep pak bro

Amazing 👏 well done

Great work !

Muy buenas las tomas y buen mod

Bagus om ilmu nya mantap