BMX Weight Weenie

[CSquare43]

For anyone interested in a retro styled bike, there's a new CW/Revcore coming out (new owners of the name). Their 1st bike is going to be a Hollywood Mike Miranda tribute, with only 50 units being produced. There's a few colors being offered including this one:

[durkonion]

Most 5-6 year olds are racing on bikes that weigh about 15 pounds. 12 is considered light. I got my son's FMF micro mini down to 11. But that was still 25% of his weight. Considering my road bike is less than 7% of my body weight, that makes his bike-to-rider weight ratio terrible. I'm hoping to get below the 10 pound range for him and still have a bike durable enough to make it through the season.

http://www.facebook.com/#!/photo.php?pi ... =fbx_album

Tell him to eat more! Problem solved.

[sakic]

Wow, I think in about 1984 I can remember the first hollywood series from hutch, pastel pink, purple and baby blue. I really dreamed about getting one. Haha.

[Thylacine]

I think you could do a crazy light and tough BMX frame in Titanium.

I'd love a project like that!

[sakic]

there has been plenty of Ti bmx frames come and go over the years. More suited to a mini or micro mini.

always have been to flexy for pro size bmxers.

[Thylacine]

there has been plenty of Ti bmx frames come and go over the years. More suited to a mini or micro mini.

always have been to flexy for pro size bmxers.

I just don't think they've been done properly. It really is a golden age of Titanium at the moment - there's never been so many tubing options.

Just remember, it's improper design that makes frames flexy, not improper materials. If you know the characteristics of a material implicitly, you can design a frame to be whatever you want it to be.

[xnavalav8r]

I've only found one source for ti BMX frames and they are in the $4000 range for a mini. I love my son, but I'm not silling to spend that much on a bike he will outgrow after 1 season. I stopped growing 20 years ago and haven't spent that much money on a frame for myself. haha

[Thylacine]

I don't see doing one being any more expensive than our current Ti MTBs, which are nowhere near USD4k!

[sakic]

I guess so then.

you can pay <$400 USD for a ~ 1.5 alu or ~ 2kg cro-mo pro size frame these days.

what would a Ti bmx race frame be? and approx how light would it be in order to be stiff and durable enough?

[xnavalav8r]

I was incorrect in my post. I confused two prices. The US$4000 was for a one-off carbon frame I saw posted. The ti frames I found were here,

http://www.cycletronix.com/

starting at US$750.00. While beautiful, I still think it's too expensive for a frame that will see 1 season of use... maybe 2. I can build a complete, high-end bike on an aluminum frame for less than that at around the same weight as ti.

[Thylacine]

I guess so then.

you can pay <$400 USD for a ~ 1.5 alu or ~ 2kg cro-mo pro size frame these days.

what would a Ti bmx race frame be? and approx how light would it be in order to be stiff and durable enough?

I'd have to design it around the rider.

There's no way it would be as cheap as off-the-shelf, but I'd be a bit perplexed if I couldn't get one under 1500g. I've built a road bike for a guy who's 6ft 6ins / 110kgs for that sort of weight, and with the amount of tubing in that frame I could build 2 BMXes!

What sort of longevity do you get out of a 400 buck Aluminium frame anyway?

[Estelja]

Here's the crank to put on your kid's BMX bike:

viewtopic.php?f=3&t=75708&start=45

220 grams!

[synchronicity]

First to answer your actual question. Carbon bmx frames.

Mongoose made the first that I know of, if you find one stay away they were extremely fragile.

Currently you have GT with the UB2. MBK from France makes a full carbon bmx and personally I think it's one of the coolest bmx frames to ever come to market. However neither of these come in 24.

A year or two ago I saw a really, really nice custom that Serotta did, it was carbon tubes with ti lugs. Imagine an ottrott in a bmx frame. I imagine if you could get them to build you one you'd be looking at a $5000 or more price tag.

Go back a couple of years and you'll find a mix of carbon tubed alloy lugged frames. Both FMF and Avent made them in cruiser. The Avent is not too difficult to find in expert cruiser which is a kids cruiser, but is difficult in pro cruiser.(I know because I'm still looking for one to match the micro my daughter has.) The FMF isn't too difficult to find. These look really good, but honestly aren't any lighter than the light aluminum frames out there.

A bmx ww project is fun, I've done it a few times for myself and my daughter. The problem is as was mentioned, bmx parts are built for abuse. I'm lucky in that I'm light (130 lbs) and after 20+ years of bmx I'm smooth and not rough on my bikes(relatively) That's allowed me to get away with mixing stuff from outside the bmx world. Places to save weight are things like the seat/post/hubs/spokes/cranks/seat collars etc... anything that you can pull from the road or mtb realm. Take for example the Redline you mentioned. While the flight cranks are light for bmx they are still almost 1200 grams. Replace it with a Storck Isis mtb crank, a TA ring, a Ti ISIS bb and a bb adapter and you save about 1.5 pounds, a little over 600 grams. Several changes like that and you can easily knock 3-5 pounds off a stock bike, but you quickly add thousands to the price. You can now get carbon rims from companies like warp9 as well. It's possible to build a ww bmx bike but it can be as expensive as doing a road project. My advice would be to get something like the stock Redline, or buy a used supercross or something similar and ride it for a year. See how you do on it and and even if it's something you want to stick with. Then you have a nice foundation to start a project from.

Nice answer & source of info.

[xnavalav8r]

11 pounds 2 ounces... I think I can get down to 10 pounds, maybe a little less. Amazing how much weight comes off when you strip the powder coat from a frame. The trophy added some of the weight back...

edited

[anodoze]

It's true if you spend $2000 and buy the hottest mini bmx parts ie answer carbon bars, fork, THE carbon seat, answer or any high end aluminum mini frame, ti bb, ti spoked wheels, answer crank, and redline mini stem you will end up with a 12.5 pound bike for a rider that weighs 50 pounds typically. That would be equivalent to a 41 pound bike for a 165 pound rider like me- about like a 26" fat tired steel huffy beach cruiser. A kid really needs a bike well under 10 pounds. I am building a sub 8 pound bmx micro- everything is done except for the rear hub and handlebars.
My start was to find a 1.5 pound frame but nothing like it existed. The best things i could find were old powerlite micro 1.95, staats micro 1.8 pounds w/paint- stripped this frame weighs 1 pound 10/11 ounces, ufo micro 1 pound 13 ounces or titan titanium micro 1 pound 15 ounce.
any of these are a good choice a foundation for a 10 pound bike. Sew-ups must be used or you'll not break 11 pounds. i currently have 3 sets of sew up wheels if anyone is interested. Forks: carbon forks are the norm but cost from $190 to $240 and weigh 15.3 ounces and up no matter what the advertising says-I sell them all and have weighed every one- buy redline aluminum fork- weighs 15.7 and cost $90- strip the paint and it will be lighter than the carbon forks. The one exception is the answer scythe sl at 12+ ounces and $280. out of space read next post.