BMX Bike Frame Geometry 101! | Everything You Need To Know!!
Vložit
- čas přidán 17. 08. 2022
- In today's Tech Thursday brought to you by Phu Vu via EPIC BMX ( / _epicbmx ) we have a highly asked for subject: BMX Bike Frame Geometry 101! | Everything You Need To Know!!
Thats right, this video is about BMX frame measurements such as the lengths of top tube, headtube steepness, headtube height, standover height, bottom bracket height, (bb height), chainstay length, fork angles, fork steepness, which all can change the way you nosewheelie (nosemanual) and how they are meant to compliment your height, size, and style of bmx riding.
Join the AlfGang Discord:
/ discord
Join this channel to get access to perks:
/ @alfredomancuso
Thanks for taking the time to watch my content! If there's anything you'd like to see, please let me know in the comments, and if you can, don't forget to drop a like!
If you'd like to support Alfredo:
For merch visit: www.AlfredoMancuso.com
/ alfredomancuso
/ alfredomancuso
/ alfredomancuso
/ alfredo.mancuso
Snapchat: AlfredoMancuso - Zábava
Thanks for all the support guys! Phu and I, appreciate it!
We appreciate you guys for the knowledge
Of course Brochochi 🤘
Thank You guys for the Epic education episode.
Alf gang
Please do saddle height and angle
Just some useful info for bike tuning geo wise.
Every .5 degree steeper you go headtube angle you lose .15 of an inch wheel base length.
Going 1 degree steeper or slacker on the Seat tube angle accounts for a .25 of an inch in top tube feel. So a 20.5 with a 1 degree steeper seat tube angle will feel more like a 20.75.
25.4mm to a inch. Which can help in fine tuning reach if you want to play with top tube length and rear end length.
With uber short rear ends there's a point where the extra length on the top tube gives you leverage on the pull up making manuals more tricky.
Bb height can also be relative. Higher bb makes spins easier an other stuff. But thin pedals can change bb height same with tire profiles. Same on the headtube. A shorter fork axle to steerer tube will steeper your headtube. Taller slacken it. Skinnier wider then tall profile rear tire and a wider taller front tire profile can raise your bb and slacken your headtube.
More spacers under your stem versus a stem that raises your bars an equal amount or just taller bars. Changes reach which changes how long the top tube feels. But can also affect leverage. Why riders like Sean burns run a flipped top load stem. It provides a different leverage point even after you account for setup differences and equaling effective bar heights.
Taller headtube helps with headset and fork strength. On frames like the tall boy or if they have gyro tabs. A 175mm fork or even on regular frames with shorter forks. If you can get the gyro to sit below the headset dust cap. You only need about 20mm 25mm at most of steerer tube besides your stem. Also means for drilling tabs you can reduce the amount of spacers needed.
But taller headtube and slightly longer fork steerer is stronger than taller bars for same effective bar height. And provides less leverage for the bars to slip on the stem or break. And done properly a flipped top loader can help counter act some of the leverage differences.
Unless you really need uber short rear ends or a low bb or uber slack headtube. Minimum 13 to 13.25 cs 75 headtube and 11.8 bb seems to make the most sense. Especially given shorter cranks popularity. For low bb stability mix lengthening stays and lowering bb. Shorter cranks should have better spins with the raised bb and more pop for hops with the rear end still stable enough for other stuff then just modern tech street.
Fork offset can help make up if you need more front end response or less. Same with tires. Thin pedals more planted into the bike but more sprocket clearance and still help with spins.
Kinda like how Ethan picked basically in the sweet spot for stand overs. 8.75 to like 9.5 ish is what looks and rides best. 10 is for tall dudes even 9.5 bur if you do alot of bars it helps. 8.75 for more whips. 9 to 9.25 sweet middle ground.
thanks for this! massive amount of great info here
This is true, that's why I had a lean back seat post back in the '80s
Love this show, I dig how Ethan is building a wheel in the background. Y’all’re hilarious and knowledgeable at the same time.
Love hearing Phu talk shop about BMX. As a car guy I can never get enough tech videos
Tried a trick geometry frame with 11.875 bb height and 21 tt and went to 11.5 bb and 20.75 tt and my riding experience has improved dramatically, 270s, fakies, half cabs, etc, all got easier for me, the right geometry can help the average rider a bunch.
Thanks for educating me Phu I'm learning all the time about the bmx bikes witch i love 💯
forgot to mention seat tube angle. Also it seems that bmx frames have been using flatland frame geometry more as time progresses. shorter chain stays and steeper head angles have been on flatland frames for decades. Although i like the look of a frame with shorter stand over height, the lower tt for clearance also has its drawbacks it makes for a weaker frame. Remember a perfect triangle is strongest so the lower the tt the more narrow the triangle thus making it weaker. So bigger standover = more even triangle = stronger frame. Cool content keep it up.
Yeah man I used to ride bmx back in the old school days and started riding again last year. New bike geometry is way better once you get used to it.
Class is in session…
Professor Phu and his 2 aides keeping it slick like sleepers dome
Another knowledgeable piece
Well done
great video bro, few people discuss this subject, a hug from your fan in Brazil.
Ur the man Phu! I wanna buy an Epic shirt! U would make a ton!
Really good video, thanks...
Great info and video!:)
Hi, can you do flatland parts and frames? Thanks!
Just about to build my bike next month and came to this video. Thank you
I'm A 42-year-old and I find myself teaching children and other people a lot about BMX and I'm always saying I learned from Phu so with that being said I want to say I appreciate it and you're wise. I've never really heard you say anything and it not come to light when it comes to certain things such as bar size and things like that it makes sense it's common sense I love Common Sense thinker.Your a BMX Ninja..also You Guys keep it Rad as fuck. I'm a Cali native(San Fernado/Venice when I get back I'll ride by.
You should make a Epic shirt that has You Ninjaed out( Cartoon status)with like You going a tornado kick with bars and flinging a chin onto the bike and flicking the bottom brack bearings in..shit flying onto the bike while Your just looking stright at US..kinda like old school bighead 80s laker shirt style.All this while Your in mid air straight Bruce Lee status. I'll take one. 😃You can be throwing the bearings with Your toes like a Shuriken.
Lloovveee watching you boys roll and, in particular, when Ethan's in the joint 🏠
Love from Ecosse.
👌 remember mid school, when seats were raised for bar spins, stems were all front loads and everyone rode slam bars and those 48 spoke triple wall rims. And most street riders rode race frames. Vhs props tapes were the sht. Where's kris bennet and joey gacia, trails are calling. 😀 yo, and ahh ride a vert ramp or trails on a flatland bike and talk more about geometry 🤣😂🤣
Thank you 🙏
Hi! Thanks a lot, could you please make a review about the new flybikes frames and bars? greets from Colombia
Look at the kick out on the forks on that dyno, you just gained an inch on the wheelbase, but the bars are closer, with short top tube, the trail is crazy on that set up.
Better get my notepad out!
🌟The more Phu know...💫
😂😂💯
14:30 I swear, 10" standover looks fucking dope. Stephan August's frames are my favorite as far as how the geometry looks. I'm also a tall dude and like to run some seat post; more standover = less exposed seatpost. Running a Magnum @9.75
Can I purchase that Tierra frame? Mine was stolen 6 years ago on Fathers Day and I want to rebuild it. Love that shape.
omg i love this guy haha
I want to see Phu ride at a spot. Mostly to prove he actually owns shoes.
I remember buying the Tierra when it came out and was hard to find. I rode that for close to a decade and still regret selling it. If you ever sell that frame, please throw me a price first. I will more than likely buy it.
That's basically what I rode but a compe. Bar spins were a lot harder, especially if you didn't have the drainpipe seat post
How about a video on different frame materials? I’m not talking high tensile steel vs chromoly but all the different chromoly different brands list
Just measured my Auburn tri-link,16"
Got a sleeper build coming from Ethan soon
Why is it in the BMX world, the seat tube from bottom bracket seat tube is considered the standover height whereas in all other bike industries the standover height includes the seat tube down to the ground? Technically, you'd think standover height includes the space under the bottom bracket so you know what the actual standover height is.
Are any of you guys going to Woodward West on Labor Day weekend
Dam I love that fly frame
Most 80s freestyle bikes were 18 inch top tube or 18.5. Dyno's were all 19 inch top tube. Redline RL20ii's are 20.5 inch,trickstars were 19 i think and General osborne pros and blood pros i think were both 20 inch top tube.
My favorite is the MR1 frame
That and the BTM by S&M are my favorites
I NEED HELP!!! I have a 29inch bmx, but it’s does not keep a good coast at all! It’s comes to a stop very very fast, I just change the free will an drive train an it didn’t make it much better!!!! So wat it is the HUBS?? Ps bike is a framed plaintiff
Hey fu could you nake a video about forks?
I love the white one sir how much for it so sir?
Just asking for a friend 😁, would a 18" rim Work on a 20,75" TT? Is this however possible?
Hey!! There's no way in hell I'm riding Trails on a Flatland Bike!! I've got a Flatland set-up 75°, 19.5", 12.5" BB Height, 12.75" Slammed Chain Stays, Zero Offset Forks, 160mm Cranks, Freecoaster, 20/9 Gearing haha, F-That on Trails haha!!! A properly tech street bike would terrifying too haha! Something like a BSD ALVX AF Frame would be scary! My Trails Frame is 74.5, 21.8, 71, 11.4, 9.2 & I run my CS's about 14/14.2" I think a decent Street Rider could probably do alright on it tbf.
I do get what you mean though, for the most part! BMX is a 20" Wheel, Frames, Forks etc parts that effect the way it feels for technical, slow, instant pop etc for street & then long & low for Trails, slack geo kinda dealy.
BB height is everthing!
Facts!
Alf could borrow my Sleeper, it has breaks!
I have a really rare subrosa alameda frame that has a super low stand over height 😬
Dirt frames have 14 to 13.5 back end with a mellow headtube angle of 74.5 street frames have a short backend 12.5 to 13 with a 75.5 head tube angle
I never see anything about race bike geometry or parts
Bmx tires are the same quality right
Sup alf
Sup Garfield!
teacher where can I buy cult frame for beginners
Welcome to Another EPIC Episode!
"your going to break your back" lol
👊🏻
Yoooo
I'm waiting to see Fu eat spicy stuff again and shit himself lol
Hahaha his stomach won’t let him
@@AlfredoMancuso hahahaha tell him don't be a spice weenie hahaha
actually 19inch frame is my preference
😎
🤝
Does Phu have an asian friend who knows MTB with that same passion in NYC?
Maybe I am tripping out after a long azz work week, but I swear Phu looked 15 years younger in the very opening scene.
Forgotten frame 21 inch top tube with repop tuffs light weight long frame for a 45 year old rider
Scam
❤️🧡💛💚💙
💜💜
Can someone help me decode a old/mid school BMX bike s/n # K6DQ002644?
Why are the wheels 16 “actually
And they say 20 but it’s length not height which is usually 8.5
the term 20" refers to the outer diameter of the tire when inflated and is a rough estimate because tires will have different sidewall heights and rims have different widths.
Fixed gear freestyle
Ahh
💯
19 is short? 😔
I want a t-shirt
I got the same a message,I sent him one of these🖕
The. Exportation. Is. The. 10. Gladiered. Have. Many. Have. Trener. Exactly. Is. Resposabily. The. Many. Disaners. Bike. Ma. Be. Yuo. Sale. After. The. Bike. Time. Champion. Use. The. Coston. Bike. Cost. Breck. More. Effective. Our. Caset. Free. Weel. Talk. About. 10. Top. Cost. Breck. Motivation.
Foos running out of video ideas
Nah hella people have been asking
Why does he use your name then?
What do you mean use my name?
Try milking the dog.
All I can say to the 13yr old that walks in complaining about geometry is Go RIDE the bike, get better...
I like this channel, but chill with the racial stuff. People are WAY more sensitive these days. 🙏
Phu won’t change haha