Lightest Bike Possible Under $1k (Part 1)

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Today I try some new CNC techniques to make a part for my Bike. Thread-milling is scary...
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[@Argosh]

That surface grinder is beginning to look weird.

[@KeithCassidy]

Really fit a front brake. I've had near misses where I would have hurt someone if I didn't have one.

[@dmorriso]

I agree... having one is cheap insurance, doesn’t require you to use it in a non-emergency. Plus, eventually you’ll blow out your knees. ;)

[@thebigdustin]

A freewheeling rear hub would be nice too. Who thought having a fixed hub was a good idea.

[@dmorriso]

Can’t use a coaster brake. Fixed gears brake by either resisting the pedals with your legs (slow) or unweighting the rear wheel by shifting your body weight forward, bracing your legs to lock the drivetrain, and setting the rear down to skid (faster). But even a rear wheel skid is less efficient than a front brake because of physics, so having a front brake for true emergency stops, while not ‘traditional’ in fixie culture, is a worthwhile compromise IMO.

[@dmorriso]

Your terms are spot on. It is simply because the use of a coaster brake makes it no longer a fixed gear bike. There is a certain enjoyment in riding a “fixie” where the pedals are always turning and you’re completely connected to the movement of the machine.

[@Thefreakyfreek]

@@dmorriso never really driven a fixy bu I had a large (dont know if it's to corect word ) skelter as a kid whit fixed gearing and the oly positive thing about it was the ability to go backwards but mostly damaged feet if you slip of

[@nutsandbolts432]

Scraping the ways. Right around the corner correct?

[@marcuschristensen4183]

They really should just get that bed ground and scrape the saddle, cross slide and tailstock

[@randombuilds8336]

Thread milling isn't bad. Big thing is to comp the tool to cut small and adjust up to size. Works really well for production in aluminum because cutters last so long with coolant. First one is always a little slow.

[@joepie221]

I saw your interview from the 2020 Bash. Interesting channel. I'll be back to watch more of your videos.

[@PhysicsAnonymous]

Thanks Joe! We are both big fans of your channel

[@St0RM33]

Give this man a lathe!

[@cmdrjkihn8955]

Two things: Safety flip flops! "Hey! Welcome to the channel!" Also, LOL with the Derpy DMU appearance. I might have to get that in a duvet cover.

[@macht4turbo]

One gear is all you need, but a single speed is more suited for me, in the city having the ability to coast and break is mandatory. Not just for me, but also for the safety of all others.

[@satibel]

I'd also include something along the lines of a 75-100W motor with a small pack (along the lines of 2Ah 6S for 100g+400g) for help in hills.

[@cooperberrysmith7701]

what does coasting have to do with safety? the brake I'm all for I just don't see what being able to coast should be "mandatory"

[@MaxMakerChannel]

That split frame problem was unexpected.

[@dmorriso]

That’s an awesome build and bike. When you tested the threads, was that a bottom bracket? I had no idea that track hubs and bottom brackets were the same thread...

[@Nasadude11]

I was thinking the same thing! It's like how a QR axle can thread into a derauiller hanger (for a very imprecise derailleur hanger alignment gauge)

[@wileecoyoti]

Sure was! Yeah bikes have all sorts of really, really weird threading and parts. It's all cobbled together from ancient standards mixed with modern companies "inventing" "new technologies" to try and push each other out of the market. Thankfully "English thread" stuck for a few things. They were kind enough to call it different names to keep it confusing though (BSA, ISO, British, English, BC.... Who knows what else).

[@reversingentropy]

Hi guys, Nice work but just a heads up, you should thread mill from the bottom up, in a tighter hole chips can accumulate on the end of the hole with no way to get out and breaking the threadmill is really easy. Also you can go way faster. Oh, one more thing, use Linux CNC already.

[@JeremyCook]

Wow, that's a nice looking rear cog. I like my (more traditional) single speed, but still haven't tried an actual fixie. Thumbs up for the Carl clip, lol.

[@cooperberrysmith7701]

I'm pretty sure fixed gear bikes were around before any kind of freewheel

[@JeremyCook]

@@cooperberrysmith7701 Hmm, I guess you're right, but seems like fixies have come into style (again?) now or in the recent past. So it's a rather unusual situation as far as what is traditional.

[@Ba-Cr]

What a beautiful piece, I myself am a big fan of CNC parts on bikes. There is just sth about it what cast parts don't have. Nice work, I am looking forward to the rest of the build!

[@mcorrade]

Awesome. Your the only youtubers I've bought a tee shirt from and I always get compliments and inquires.

[@mannycalavera121]

Have the lathe bed reground, few hundred bucks, then you can scrap in all the saddle, tailstock, etc

[@ianide2480]

My favorite part was the background music. Who needs content when you can play a catchy tune. Kinda reminds of TV commercials, insert music and a couple words "hey buy our crap" and poof, production done. The only difference was he forgot to convince me to buy something. Forget the explanation of how you overcame hurdles with milling the threads. Never mind CAD/CAM walk-through. The song "Tinkle Tinkle Beep Boop" written by Annoy Your Neighbors, well that was a great touch. Keep up the great work. Hope you got some sort of "rating" from the full 8 minutes that I managed to watch.

[@capnthepeafarmer]

You should make a strap belt wrench using the same drive belt that the bike will use. No need to worry about marring then.

[@CharlieInshawDrums08]

I'm pretty sure death metal unicorns would apply copious pinch harmonics! CHUGA-WEEEEE! Great videos guys!

[@BreakingTaps]

Threadmilling went great! Not sure I'll ever get used to it... always full-clench-mode engaged the whole time. :) What coolant are you using in the mister btw? Been unhappy with mine (TRIM Mist) and looking to change.

[@flantc]

That first milling operation was pretty "fly".... hahaha... crack myself up... because you know "fly" like the kids say but... never mind...

[@SkaeGTV]

When you are milling something, i think it would be a lot better if you made the camera "follow" the part instead of the tool. (for example, mounting the camera to the bed) I am 95% sure it will make your sped up clips a lot more enjoyable to watch :) otherwise a very nice video, keep it up :)

[@PhysicsAnonymous]

Agreed! I will work on that for the next videos

[@peevzi]

nooooo please. this gives motion sickness to a lot of people

[@fractalengineering]

Very clean result on that rear sprocket man; you may have shaved off a little more weight by switching to the centertrack version; I build me one a couple years ago with a custom made frame and it's been absolutely solid

[@johnwayne2103]

That is impressive! As someone who was in love with bike ridding and loved the cycling sport I fell out of love with the sport when it became so exorbitantly expensive. Some great innovation no doubt. Suntour, Sachs, Campagnolo and Shimano and the lessor known manufacturers of components it's been an interesting journey.

[@chrisj4570g]

Bare feet is is unsafe! You must wear Safety Crocs. I won’t go to my shop without them! I go the extra mile and wear socks, too. Cool project, I’m lookin forward to seeing the end result. I *had* a fixed gear. Knee surgery (each knee) some 30 years ago reminded me that fixed was a bad idea. Had to switch to a freewheel. Which honestly I prefer. Too many hills around here.

[@folxam]

God DAMN you. Now I have a mug and a t-shirt on the way, sooo not necessary. A well, I do drink coffe and need to be clothed, so ok. Death Metal Unicorn, deploy.

[@firesurfer]

Now that you have this ultra-lightweight gimmick done, you must put a front brake on. Period. Unless you never intend to actually ride it on the road.

[@midgoog2]

New Guy ... You need to investigate the All Australian machine shop thong range of safety footwear available at a surf shop or $1 store near you. 😉😁😂😂😂 Cheers Eric

[@HappilyHomicidalHooligan]

Please add standard C-Clamp style wheel rim or Disc breaks to both wheels and not rely on back-pedaling to stop. The faster you're going, the harder it will be to stop suddenly in an emergency...

[@cooperberrysmith7701]

I think he might know that already..

[@HappilyHomicidalHooligan]

@@cooperberrysmith7701 Probably, but the video didn't make that clear and even really smart people occasionally forget something important...

[@paulojrg]

SRAM has/had a 2 speed "Automatix" internal hub that you could possibly replicate with a lighter external case which is enough for almost any around town riding and to me brakes are mandatory. 👍

[@baretvickery5681]

You said your CNC doesn't have a lot of low end torque right now. Could you expand on what you mean? I just finished watching your video on liking the teknic sd servos.

[@andriosz]

8:26 shouldn't you use a belt wrench? Chain wrench was sooo anti-climatic :P ;)

[@TheZzziggy]

It's a little bit hairy! - says a bald guy. By the way, I don't get it, why a belt hub can't have a free-wheeling feature? Sorry if I miss an obvious answer.

[@PhysicsAnonymous]

It can, but my bike can't because I will be running without brakes

[@frogbertrocks]

Wear a helmet. It's not like it's going to mess up your hair. 😁

[@Thefreakyfreek]

Helmets are for when you are going to do risky scary stuf

[@raxxo69]

@@Thefreakyfreek No, helmets are for people who have something to protect . . .

[@SimoWill75]

Helmets are for when that car comes out of fucking nowhere

[@satibel]

but a helmet's extra weiiight.

[@DavePB420]

Very interesting CNC job to get your teeth into. Nice to see the project around the belt drive system too!

[@acme511]

What CNC machine do you use? And what are your thoughts on lowest price but good as possible CNC for beginner?

[@TheCalvinSkinner]

I was totally wondering about the tram LOL

[@Thefreakyfreek]

Jea the first time I used treadmills on a cnc macine I was scared to but on a manual macine I was prity comfy so no big deal to switch to cnc

[@Guarkernmehl]

That's some nice neighbourhood you live in

[@maxst2]

Why couldn't you have a one way bearing to have coasting... and brakes... cause those are kinda needed.

[@Astjaeger]

Since you drive and break with this thing, wouldn't a spline be better... Will the torque alter a lot in both directions so the threads might come lose?

[@andriosz]

There is counter locking nut there too.

[@bs89]

What probe are you using, and would you recommend it. Have a CNC converted PM25MV and have been looking for decent probe.

[@routercnc9517]

I really enjoy the death metal unicorn music at the end of the video. Is it in dropped C ?

[@veconsports7650]

Theyd make you add weights to the saddle if u wanted to race that thing on the track down there - which we’d highly recommend doing ;-)

[@peetiegonzalez1845]

"That means you don't have brakes"... er, no it doesn't. There's no excuse for not having a front brake. No matter how good you think you are at stopping the back wheel, a front brake is far more efficient. inb4 any replies saying "you can't steer with a locked front wheel" or "you'll go flying over the handlebars" -- Who says you need to lock up the wheel? Learn to brake properly. No road bike or MTB rider would be stupid enough to omit the front brake, why should you?

[@musicwhiz711]

This is a super cool series! Coming from a fellow designer/fixie rider!

[@inifin8]

Couldn't you use ratchet mechanism for pedals?

[@jolangse]

I love the derpy-cutesey metal-unicorn that appeared at 17:03 before the "Punk-rock-unicorn t-shirt?" question! Laughed out loud when I spotted it. I can haz wallpaper of that plz? kthx.

[@Cergorach]

This is a Big Boy BMX bike! ;-) It's been decades since I've had to break with my feet, I'm curious how quickly you would relearn breaking like that (and do it safely in traffic)...

[@sythe64]

Got to say the mixed units thumbnail did get me to watch.

[@ILikeWeatherGuy]

wait so how do you tension?

[@cooperberrysmith7701]

slide the wheel forward or back using the horizontal dropouts

[@vasyapupken]

using fixed gear hub on a bicycle is like using DOS on PC.

[@opendstudio7141]

It's a good thing you are apprehensive about feeds and speeds. I would have launched that thing into orbit on OP#2 using that holding method. 😉

[@beachboardfan9544]

So wait, how much weight did that save? How much did the bike originally save and whats the target weight? Metrics man!!!

[@johnmurray9746]

Awesome build! No helmet tho? 🤔

[@johnporter8896]

You should invest in a v block for the cnc vise

[@TheArtificiallyIntelligent]

What was that yellow thing the part went into?

[@simplexicated]

This seems to be the only off the shelf version of what's made in this video: SKU:CDXR22TH Link: velorution.com/gates-cdx-rear-sprocket-22t-thread-on.html Pricey!

[@PhysicsAnonymous]

Indeed! I didn't know gates sold a thread on version. I also have an older version of their belt system, so I would have to spend a lot more to get that to work.

[@simplexicated]

@@PhysicsAnonymous I imagine the belt-line is different on your version. Dying for these belt systems to become more mainstream and affordable as a lazy commuter and fixed gear fan. Great video by the way. Let's hope this inspires some mass production of a thread on lock-ring style.

[@mikaelhenning2]

As always, a fun and informative video, Awesome! How is the old laser cutter doing? Do you still need the .7 ms delay circuit? BTW, what FW are you running on the SBase?

[@PeterKNoone]

I'm almost as bad as the Linux CNC people but how about an Elegoo Mars linear rail install video with part list in the description.....I've had your part for this sitting on my desk for weeks.

[@AtHeartEngineer]

If you are looking for an easier video to make, I'd be interested in seeing the behind the scenes/order of operations for how you shoot/edit video. Starting this channel soon (finishing up a house reno first) and would like tips.

[@ruirodrigues9122]

You guys every going to try to add the 4th and 5th axis trunnion table?/Fabricate one for the cnc?

[@UltraBadass]

Thanks for not making me convert lbs to kg

[@SadeXo1]

Hi how can i get Unicorn for my desktop wallpaper?

[@TheLordFisch]

You could get them from the redbubble source: White Background: ih1.redbubble.net/image.1475977782.1595/flat,1000x788,075,f.jpg Black Background: ih1.redbubble.net/image.1475958703.1191/flat,1000x788,075,f.jpg Unfortunately they are only 1000px*788px, but you could simple center them and add a solid background colour underneath.

[@mlee6050]

I got no grease on my chain as use wax

[@jatriska]

Really glad to see a new video!

[@whistlingoat801]

riding fixed gear brakeless without toeclips/pedal straps/clipless setup is almost a death wish. Your slowing distance and control over the bike is significantly decreased.

[@santiago_n3651]

Great video, but bro you should fix your posture. Try to keep your ears aligned with your spine. You'll feel a hell of a lot better.

[@RazorSkinned86]

Have you consider yet using a Mesa FPGA card and LinuxCNC?

[@ihaveanaccnow]

Anyone know what the name of the song playing at 6:00 is?

[@TrPrecisionMachining]

very good video..thanks for your time

[@twofortytwo]

Did you just reverse engineer the old sprocket? I cannot find a drawing for the belts. The drawings for the sprockets that I found from Gates is missing some information. Neat buildup on the bike.

[@jonnoMoto]

I'm guessing you're a member of the weight weenies forum.

[@diamonddogie]

If so, bike should have been all carbon

[@ke0kie]

skid stop throw belt?

[@jbkltc4469]

at least get some pedal straps (or clips) so that you can slow down appropiately

[@DPTech_workroom]

I like DIY and CNC!!!

[@hansdietrich83]

Full Offense: Fixies are stupid, not because they are dangerous for the rider but to other people.

[@RCDinsmore]

Did you ever get the lathe working? ...'Cause I think making round parts, boring and threading would traditionally be done on a lathe, but pretty cool to see it done on a mill. I guess there's more than one way to kill a cat. Probably shouldn't tell your cat that.

[@Thorhian]

It's time to run LinuxCNC buddy. :)

[@Thefreakyfreek]

Came here to say the same

[@Shiro-vd5iq]

the music please

[@claeswikberg8958]

more important, where can i find the music in its entirety?

[@android01978]

Claes Wikberg is that so you can burn every copy?

[@xXWHO111Xx]

If you tell me the name of or link me to the full version of the Death Metal Unicorn song I will buy a Death Metal Unicorn t-shirt

[@jcknight87]

artlist.io/song/11430/roots

[@xXWHO111Xx]

@@jcknight87 I'm a man of my word. I'm buying a t-shirt

[@StanislavJochman]

How can I get that music?

[@aaronslife4635]

Something something LinuxCNC 😀

[@Abrikosmanden]

Belt drive is fantastic! I've got two belt drive bikes now, and I'm NOT going back to chains ever again!!! Milling your own sprocket is really really impressive. And now the sucky part of the comment: Please use a helmet! You're just not in control of other shit heads on the road, and no matter how aware and quick to respond you feel, you're really not! Helmets are hot, ugly and not cool at all, but please use one; we like your brain!!!!

[@nscantling]

I'm still patiently waiting on the lathe to get restored.

[@fantasmag00ria]

What's the probe used around 5:25?

[@ponydown418]

It might be a drewtronics prope. I just bought one a couple of weeks ago.

[@SomeOtherGuyOrPerson]

Drewtronics S500LED, that PA modded with a TTS-style shank. Probe: drewtronics.org/s5000led Modded in this video: kzbin.info/www/bejne/mXLNk3h6m52hqbM Also available straight from Drewtronics with TTS-compatible shank: drewtronics.org/s5000led-tts-1 I have one of the TTS Drewtronics probes on my CNC-converted mini mill, and it's really slick. Definitely worth the price IMO.

[@SomeOtherGuyOrPerson]

Bonus: Video of Drewtronics scratch-built CNC lathe where he makes a probe part: kzbin.info/www/bejne/rImYi3xtoKd-ldE

[@fantasmag00ria]

​@@SomeOtherGuyOrPerson ​ @Pony Down 418 Cool, thanks guys!

[@tntodorov]

Thanks for the DMU t-shirts! But please, please, please! Add kid sizes too (Redbubble has kids apparel too, so the site makes it available...)!

[@PhysicsAnonymous]

Done!

[@TiaNloko]

How's the lathe doing? LOL

[@a577536]

Yay stuff!

[@ClayKraut]

dizzy. so dizzy now

[@retepaskab]

Ok, but it should be lightest bike possible under $X / km lifetime.

[@FKreider]

Is the bike really under $1k considering the cost of the CNC mill to make that part? :) :)

[@HappilyHomicidalHooligan]

Why not do yourself a favour and machine everything but the threads on the CNC Mill and then cut the threads on the Lathe?

[@stephensimpson5283]

SCRAPE!!!!

[@adrianbekerian4518]

Es una lastima que no tenes traductor así supiera que comentas.

[@TizonaAmanthia]

I don't wanna be "that guy, or any kind of nervous nellie" but...would you mind putting a bike helmet on? I'm not much for safety gear, but I've become pretty firm about protecting my melon, and other people's.

[@macht4turbo]

It is more complicated than that. Studies have shown that car drivers will be more aggressive towards you, when you wear a helmet and the riders themselves will be more aggressive in their riding as well. So more accidents with helmets than with no helmet, which negates the protection of helmets.

[@TizonaAmanthia]

@@macht4turbo on the surface, that sounds preposterous...but...I don't think it's going to stop me from wearing a helmet. I'm sorta curious about those "Studies" you mention. dont take it personally, I doubt everyone.

[@macht4turbo]

@@TizonaAmanthia The phenomenon is called risk compensation. There are studies supporting this and some that don't, like inb most fields of science, it is up for debate. Meta analysis: shorturl.at/xHOW9 Supporting studie: shorturl.at/cilG4 Article: shorturl.at/fUWX1 Another good article discussing the research: shorturl.at/jAW07 With conflicting research, you have to make up your own mind, however for me it is very plausible and i can see the effect on myself. I often drive in traffic and i feel like car drivers will pass me closer, if i wear a helmet.

[@TizonaAmanthia]

@@macht4turbo *double thumbs up* I haven't ridden a bike in quite a long time, but...all I can say, based on MY "Research" is, I'm less worried about cars being hostile towards me, and more about ANYTHING that could potentially unseat me, a stick, a bike malfunction, and suddently, I"m biting the dirt. and I just...insist that my dome is safe. But thanks for supporting your claim.

[@russhellmy]

13lbs is under 6kg.

[@bassgojoe]

Unprotected threads in a vibratory tumbler? Hmm...

[@John_Ridley]

@17:03 lol

[@0ADVISOR0]

no breaks, no BREAKS, NOOO BREAKS!!!?=!==! ugh.. I hope you don't crash into my car and then pretend that I'm the culprit. Never the less, save riding! =D