Abu Mahendra

I am considering purchasing one of the frames pictured below:







In case it is not obvious they are made of bamboo. My questions/concerns are as follows:

1. The BB shell is not threaded, and seems a bit wider than what i am used to. What type of BB would it need?

2. (question withdrawn)

3. Notice that they are for disk brakes, and that one of the three frames has a brace/truss spanning the seat and chain stays. Any concerns about the braking forces acting on the stays? Is the frame with the brace/truss the preferred choice?

4. Can a dereilleur hanger and dereilleur be attached?

Please point out any other potential complications or weaknesses. I have till early next week to decide. Thanks.

carlosponti

if bottom shell is not threaded then you have to look for a press fit bottom bracket or they have press fit cups with threads. head tube is going to need press fit bearing races. and it looks like it has an integrated derailleur hanger on the drive side already so a derailleur can be installed. that's an interesting project would be neat to see how it comes together.

cny-bikeman

1. Why not ask the supplier what is compatible?
2. If you don't know that neither head tubes nor modern forks are threaded you probably should not be doing a scratch build.
3. I'm sure one or more of the many, many people here who are experienced with bamboo frames can properly advise you. Seriously, I would suggest you look online for reviews of bamboo frames, though I don't know if they will help you as there's no indication of a brand or manufacturer on the frames you are considering.
4. MOST derailleur hangers are designed to fit forward facing dropouts, but there are other options: Derailleur hangers for track fork ends (AKA horizontal rear facing dropouts)

Abu Mahendra

1. The manufacturer is defunct. There is no one to ask, except for a sales woman who knows nothing about bikes.
2. No need to be a pr!ck about it. I've done a few builds already. Here are two examples:





4. Actually, dereilleur setups usually call for vertical dropouts.

cny-bikeman

1. My question was understandable, given the lack of relevant info on the original post
2. Mine was a reasonable observation, given that there's no such thing as a threaded head tube and no indication that you had ever built a bike.
4. Not saying it does not exist, but I have never seen a bike with vertical dropouts without an integrated hanger.

Abu Mahendra

of course. you cut yourself a bit of slack, give yourself the benefit of the doubt. But you do no such thing to others. Yes, I had forgotten about threadless and threaded headsets. Again, you didn't have to be condescending pr!ck. Do us a favor, and stay off the thread.

Over & out.

wrk101

What's under the small diameter section of the seat tube? I assume there is a metal section. I would think the larger diameter continuous bamboo would be better.

Well in the last picture, it looks like the seat tube is actually two pieces of bamboo, one small diameter, the other large. I'm not a fan of that design, its one more joint in the bamboo.


While the second one does not have a diagonal piece of bamboo adding support to the chain stay, the first one does not have a support in the brake bridge area. So that is kind of a wash to me.

There are threadless BB out there, measure the width when you get it.

I'd want to know more about the rear brake cable guides on the green/brown bike. They seem to disappear after the top tube. Odd. The other bike, the cable guides continue on the seat stay.



I guess both are meant to be 1 by X drivetrain, as I don't see any cable guides for an FD, nor mounting points.

Sure looks like the drive side drop out has a mounting point for an RD. Unusual with backward facing (track style) drop outs. I'd be tempted to go IGH instead. And since 90% of your braking is up front, I'd get as disk front fork, maybe go rim brake in the rear.

I signed up for a bamboo frame building class, but unfortunately, it was cancelled. I took a steel frame building class, and learned I was not a skilled TIG welder.......

Abu Mahendra

Good eye! Thanks for your observations. I'll take them into account when i go back next week. Cheers.

evan326

You really need to chill out when coming here asking for help. @cny-bikeman was spot on and not being a dick.
If the BB isn't threaded then manufacturing quality matters more if the bearings or cups need to be pressed in. With an unknown brand of a wooden bike, I would pass. Disk brakes also stress a bike frame a bit more and I personally wouldn't trust that to a brandless bamboo bike.

HillRider

1.Given that the manufacturer is no longer in existence and the sales woman can't give you any information I strongly recommend you pass on any of these frames. Bamboo frames are difficult enough to build properly that I'd really want to have good information before buying. For example, are the bottom bracket shell and headtube machined to proper dimensions and tolerances?

2. cny-bikeman was being anything but a prick, he was trying to help you and you took offense to what was really good information. Your original posting did not give much indication that you knew what you were getting into.

As to the drop outs on those frames, they are more suitable for a single speed or IGH drivetrain.

blamester

Entirely agree.
No one here can really help. But if they are cheap enough, buy and use your own best judgement to see if they are worth building up.

fietsbob

there are bamboo DIY frame kits why not go in that direction? it will give you a hobby, too..

sch

If prior posters haven't noticed the OP in in Bali. A google on threadless bottom brackets will give the OP some
idea of what is out there. OP should carefully measure the BB shell on the frame they are interested in as
standard BB shell diameters are in the 1.375" ID range or a bit less, nominal 34-35 mm so any threadless BB
used will assume an ID in that range. Width should be at least 68 mm and no more than 73 mm. The frame
with the diagonal brace seems best fitted for disk brakes. Frames look like BMX, one for single speed, others
for RD only, but on recheck I wonder if the two frames with smaller tubing above the BB area are meant for
FD clampon mounting?

GrainBrain

These frames remind me of prototype frames. Weird cable routing and most importantly ugly dropouts.

One of the dropouts still has the printing on it from the plate of aluminum it was cut from. These frames just don't seem like they were ready for public use.

Beautiful looking frames, ugly dropouts! They could have at least anodized the drops or even painted them before assembling.

HillRider

That probably is what they were. Based on no technical information and a defunct maker, I have to conclude the frames were experimental. As such, I again recommend that the OP pass on buying any of them.

Abu Mahendra

The frames were produced/designed by an American fellow, built with Indonesian labor and bamboo expertise, in Bali. His company rented and sold bamboo bikes to fancy, boutique resorts, but it went bust. Therefore all frames, some used, some new, are for sale. Some are obvious duds due to scratches and scuffs, but some are still in great condition. In the hand, and visually they look and feel well made and solid. And they go for about $125 apiece. I am looking to pick up a two. One to build as a rigid, fat-tire dandy leisure urban bike (no, no off-road or rough use), anf one to hang on a wall as decoration. Cheers.

grizzly59

I would say you have to be careful if there are panda bears about.

Abu Mahendra

My wife beat you to the punch with that one...

cny-bikeman

In retrospect it seems to me exceedingly presumptuous that someone who would feel free to disparage me for not being helpful would dole out little bits of info at a time, withholding much of what was needed for others to truly help until two days and 18 posts had elapsed. As you don't value it anyway you will be happy to know that I will never again bother you with my input.

p.s. I let your insulting posts stand only because they provided their own rebuttal.

Abu Mahendra

The questions below were of a technical nature, about BBs, RD hangers, dropouts, structural integrity. The answers should not matter whether we were talking about Berlin, Boston, or Bali. Nothing of what i added as background changes the technical calculus.

Awsome, look forward to your making good on your vow to never interject yourself in my threads/posts. Ciao.

cny-bikeman

You are correct, the background of the frame, the price you would have to pay and the use you intended tor them were relevant information no matter where you were located. Goodbye.

sunburst

gorgeous mixte! I want one. And coincidentally I put that same saddle on my 20" wheeled Bike Friday.

Abu Mahendra

This old dog?


The manufacturer went bust too, so I am afraid I have one of only a very few among a limited run. But if you come to Bali, you could take it off my hands, if you'd like...

CliffordK

That is what I was thinking too... BMX style.

What are the goals?

I don't think they have the mini-velo dimensions. Short head tube. Probably short wheelbase.

As far as bottom brackets, I think there are 3 different common threadless press bottom brackets.

• American/Ashtabula One-Piece bottom bracket. This might not be unexpected for a BMX style frame.
• BB30
• PF30

Others? There may also be threadless kits that will fit into a standard English threaded shell (or close... just in case one ruins one's threads).

I think there are adapters for rear facing "track" dropouts. Not as good as a normal hanger, or even a "claw", but it should work.

Problem Solvers Chain Tensioner W/Hanger | Jenson USA



If you really want a bamboo bike, there are also DIY bamboo bike kits that would be worth considering.

Or, if you live in a place where bamboo (and perhaps HEMP) are readily available, then you could look at some instruction websites and perhaps make your own, canablizing things like bottom brackets and dropouts from junker bikes.

sunburst

Well, I met someone from Bali a month ago. He lives in San Francisco and is a real cycling enthusiast. So stranger things have happened (than me going to Bali) ...

Here's mine. I even have a similar bag to yours from some custom maker in the US.