Full suspension carbon fiber frames under 700USD/500€?

[fellow]

Im looking for a full suspension carbon fiber frame suitable for "in-tube" 18650 battery placement (straight tubes). This one is 489USD, but the shipping is expensive:

http://www.aliexpress.com/item/2014-Novel-item-Monocoque-26er-carbon-mountain-bike-frames-full-suspension-ex-factory-price-for-sale/1575757943.html

This one is carbon, suitable for in-frame batteries, but not full suspension (417USD):
http://www.aliexpress.com/item/NEASTY-Carbon-mountain-bicycle-frame-carbon-frame-guangzhou-factory/563000926.html

Are there any other carbon frame choices, preferably with rear suspension pivot point at the bottom bracket?

 

[MadRhino]

If you are budget limited to 700$, don't buy a CF MTB frame.
You'd better go for Alu at that price, and even then you are far from top quality frames.

 

[etard]

That frame may come with a warranty but with buyer paying shipping, you might as well forget it. It does look promising though. I am surprised they actually did real testing on the frame for strength. However, there is no way of knowing if the frames they had tested, and the one you actually receive are even comparable. Also, that price doesn't include the shock, so unless you already have a ton of parts ready to put on the frame, the "bargain" price of this frame quickly dissipates.

I think the better route to go would be to wait for a damaged CF bike to come up for sale, overbuilding the point of failure so that it is stronger than original.

 

[Drunkskunk]

Discount CF frames are like Discount surgery. It saves you money, and you might even survive.

CF frame failures are well known and usually spectacular. And that's on good frames. CF is not the sort of thing that can be made cheaply. Like Fiberglass, it needs to be hand laid up, but unlike fiberglass, the technician doing the layup needs to be highly skilled, as even a very small mistake can cause a fatal flaw. Its not the sort of job you want unskilled factory labor doing.

On top of that, CF is used for weight savings. Meaning that if the bike doesn't need it, it wouldn't have it. So there is no place to safely cut access into a CF frame to add batteries. Grab an Aluminum frame , or even better, a steel frame from a bike designed to be strong rather than light.

 

[fellow]

Grab an Aluminum frame , or even better, a steel frame from a bike designed to be strong rather than light.

My Interceptor aluminium e-bike weights 16,5kg, and I'm desperate to shave off a few grams more. I hate owning a bike that my wife can't carry around . I think chinaese CF is my only choice, but recently annonunced short carbon fiber 3D printer may be an interesting option: https://www.youtube.com/watch?v=Y5wjjDBdgeE
This is the taste of what I would like to get 3D-printed (cross-section of a 4 X 18550 in-frame/tube for the Interceptor II). Those carbon fiber 3D printers really got to get bigger soon! Few CF bike frames printed and they are payed off

 

[fellow]

Here are two interesting videos:
[youtube]-lsDXEEUlRE[/youtube]
https://www.youtube.com/watch?v=-lsDXEEUlRE

[youtube]ZltVTZkzIuY[/youtube]
https://www.youtube.com/watch?v=ZltVTZkzIuY

 

[zener]

Audi build a ebike made of it and trys to sell it for big monay.
http://www.bustedcarbon.com/
Watch them all and than u know why it is not a good idea. (even from audi)

Aluminium is the best when designed good.
Or if you have the monay buy titanium lasts for ever. (even dont need paint)

 

[fellow]

Ouch! I saw that page earlier but it always hurts to look at it .

 

[Dudeofdoom]

Or if you have the monay buy titanium lasts for ever. (even dont need paint)

Nope it don't the welds let go

I do like the CF frames and I dont think they are as bad as made out - the problem is like ti when it let goes it just goes as opposed to metal which sometimes gives a bit of warning( if your lucky). Although you can break them all if you try.

I wouldn't get into butchering one for an ebike you really want one designed up front with a battery compartment, all the stress analysis pre done and frame designed to cope.

DoD

 

[liveforphysics]

I've never had an aluminum bicycle frame that didn't break on me. I consider them disposable frames.

However, the failure modes were all graceful, which carbon seldom gives you.

Many of the cheap carbon bike frames on ebay from China and Taiwan are made in the same factories by the same people with the same materials as some of the premier bicycle frames, because they are the same factory making them.

Like any material, carbon has its weaknesses and strengths. I don't think being noob-frame-mod-friendly is one of its strengths though, but neither is aluminum (due to heat treatment requirements).

 

[MadRhino]

I never had a bike frame that didn't fail on me. Yet I prefer to see them fail progressively, and to decide myself when it is too dangerous to ride.

For best handling, the stiffer the better, but stiffer also makes for higher chances of dramatic failures.
I like CF frames when they are thick enough, but most of them are made thin to achieve very low weight.
MTB frames are very few to be good, no matter the materials used. Some bend and some break, most are made to be disposable and manufacturers don't care much if you are gonna break your neck on a maple tree after your frame failed on you.

Hitting a tube with a hammer is not a proper test for a bike frame, the vid is deceptive.
A good MTB CF frame is expansive because it is made with a lot of CF layers. No matter the materials used, any frame shape and thickness should be designed and tested to repeatedly resist the twisting forces that it will suffer hard cornering on a mountain trail, or taking the hit of suspension bottoming.

 

[Punx0r]

I admit I was suprised how tough that CF frame was to hammering. I guess the lay-up was done to ensure strength in both directions, not optimised to withstand the normal loads.

A good CF frame has got to be an impressive piece of technology and engineering, but a cheap seems to fall foul of the light, strong, cheap (pick two) rule.

 

[Dudeofdoom]

I admit I was suprised how tough that CF frame was to hammering. I guess the lay-up was done to ensure strength in both directions, not optimised to withstand the normal loads.

A good CF frame has got to be an impressive piece of technology and engineering, but a cheap seems to fall foul of the light, strong, cheap (pick two) rule.

Mmm well I got my Lucher carbon frame from on-one on special for £249 and have been looking at some nice chinerrelo frames for £250-300
which makes me think that the rule doesn't have to hold

Mind you I was thinking about this thread as I was getting air on the the speed humps on my fully carbon frame and fork bike this morning

DoD

 

[fellow]

Dude of doom: Was it this one you bought for cheap? Before or after?
http://forallmyfriends.com/2011/08/07/broken-chinese-frameset/

 

[zener]

I would never buy a carbon fiber frame when it not have a 10 year warranty with inclusion of ebike usage. ( and please under $5k )

 

[fellow]

I would never buy a carbon fiber frame when it not have a 10 year warranty with inclusion of ebike usage. ( and please under $5k )

After all those terrible pictures of broken frames, I'm considering this one. I believe it's under 5K, 10 years warranty and its a lot of carbon in it :

 

[zener]

I would never buy a carbon fiber frame when it not have a 10 year warranty with inclusion of ebike usage. ( and please under $5k )

After all those terrible pictures of broken frames, I'm considering this one. I believe it's under 5K, 10 years warranty and its a lot of carbon in it :

Looks like model steal from th
I like the saddle and front brake the most. :wink:
There is nothing better than fire hardened construction carbon steel.

Edit: 10 years warranty including parking in the rain?

 

[Dudeofdoom]

Dude of doom: Was it this one you bought for cheap? Before or after?
http://forallmyfriends.com/2011/08/07/broken-chinese-frameset/

Frame didn't fail though - only the forks.... .

 

[middriveebike]

I really doubt if the CF frame can last even one day of use with 4Kg of batteries inside its frame and with high torque and stress from the motor.
Let's say if you can place the batteries inside the tube somehow, how are you going to take it out later on for, let's say recharge or replace the batteries?
If one wire within the batteries are damaged, how are you going to fix that?

 

[fellow]

really doubt if the CF frame can last even one day of use with 4Kg of batteries inside its frame and with high torque and stress from the motor.
Let's say if you can place the batteries inside the tube somehow, how are you going to take it out later on for, let's say recharge or replace the batteries?
If one wire within the batteries are damaged, how are you going to fix that?

I'm sure you are right about the stress, maybe the Alu is safer after all? Take a look at my build in/under the signature, batteries are inside the tubes and they are removable. Replacing them is not a problem, as they are not welded shut. But it's a bit of a job, nothing you do in 5 minutes. I'm will probably replace them after 300-500 cycles, hopefully to something 4Ah+/cell that is state of the art in few years. Wires are double insulated 2G1,5mm2, tripple fused. Didn't understood about the recharging, I'm doing it as everybody else do?

 

[fellow]

This video is scary! http://www.pinkbike.com/video/332120/