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Carbon fibre A Arm
Posted: Fri Feb 04, 2011 5:17 pm
by Kieran R1200R
How many of you guys would be interested in a full carbon fibre
A Arm, that's the front paralever triangle at the front of your bike, from BST
that make carbon fibre wheels.
You will loose about 3kg and the bling factor will be awesome!
Cost is to likely be about $1200 to $1400 USD.
First production in around May 2011, so plenty of time to start saving.
Re: Carbon fibre A Arm
Posted: Fri Feb 04, 2011 6:29 pm
by Acpantera
How about some other light weight stuff like side/center stands and rear sub frames made of carbon fiber, aluminum or titanium?
Re: Carbon fibre A Arm
Posted: Fri Feb 04, 2011 6:40 pm
by Kieran R1200R
They would need all that stuff to fabricate it, and unless someone lends then the items it wont happen.
Also I bet from this board that I will be the only one that purchases this arm.
So when you factor that in where is the profit for BST.
We've got 16 people so far that will buy this arm from other forums.
I would say that once this order is filled it will be the first and last.
The A Arm is the same on the R12S, R12RT, R12R, R12ST.
Also it will come with a offset hole so you can change the rake of the forks for quicker steering!
Re: Carbon fibre A Arm
Posted: Fri Feb 04, 2011 9:07 pm
by mogu83
I think I'll just cut back on the beer and chips, my doctor keeps asking me to drop 10 pounds.

Re: Carbon fibre A Arm
Posted: Sat Feb 05, 2011 1:27 pm
by rockbottom
mogu83 wrote:I think I'll just cut back on the beer and chips, my doctor keeps asking me to drop 10 pounds.

I used to feel that way when I bicycled a lot. I resisted the urge to save 20 grams here and there by replacing steel or aluminum parts with titanium and carbon given that I was 40 lbs overweight.
Re: Carbon fibre A Arm
Posted: Sun Feb 06, 2011 11:22 am
by Acpantera
On another note I think I just invented a new food, The CARB-N-FIBER pancake. Just add
benefiber to your pancake mix (I like cinnamon in it too). The effect will leave a lighter weight.
Re: Carbon fibre A Arm
Posted: Sun Feb 06, 2011 5:22 pm
by Rolando33
Kieran,
That sounds awesome, but what about the safety factor in a "t-bone" crash? The Telelever is part of the BMW crumple zone in a crash. I'd love to save the weight, but from a performance-safety-dollar value feature, I just justify it. Your wheels and handle bars though----they are so worth it!!
Re: Carbon fibre A Arm
Posted: Mon Feb 07, 2011 1:22 am
by Kieran R1200R
Rolando33 wrote:Kieran,
That sounds awesome, but what about the safety factor in a "t-bone" crash? The Telelever is part of the BMW crumple zone in a crash. I'd love to save the weight, but from a performance-safety-dollar value feature, I just justify it. Your wheels and handle bars though----they are so worth it!!
I can't answer that with any tech!
But I have the wheels and I think you could say the same thing for them.
In a T Bone situation and heaven for bid, I think your goose is cooked either way!
Re: Carbon fiber A Arm
Posted: Mon Feb 07, 2011 7:47 am
by mogu83
Maybe someone can answer this on carbon fiber. I have three bikes in the garage that are 30+ years old they are in good shape and just as serviceable as when they were new. What is the service life of carbon fiber when exposed to sunlight for years? I've seen carbon fiber body parts a few years old that look really ratty. I know that a lot of race bikes are loaded with the stuff but their service life is usually around five years.
I think they also use carbon fiber in aircraft, any pilots out there that have a read on that.
Re: Carbon fibre A Arm
Posted: Tue Feb 08, 2011 1:08 am
by Rolando33
@Kieran,
Well, since you brought it up, what do you think about your carbon wheels? Did they help the performance? Durability? Price in Dollars or Euros? I have an R12S, and I would seriously consider those---the bling factor is way up there for that bike.
upload image
hosting images
Re: Carbon fiber A Arm
Posted: Tue Feb 08, 2011 2:08 am
by Kieran R1200R
mogu83 wrote:Maybe someone can answer this on carbon fiber. I have three bikes in the garage that are 30+ years old they are in good shape and just as serviceable as when they were new. What is the service life of carbon fiber when exposed to sunlight for years? I've seen carbon fiber body parts a few years old that look really ratty. I know that a lot of race bikes are loaded with the stuff but their service life is usually around five years.
I think they also use carbon fiber in aircraft, any pilots out there that have a read on that.
I think it would be like looking after your paint job on a car, if you wax it and take care it lasts, if you don't, well we all know that!
Re: Carbon fibre A Arm
Posted: Tue Feb 08, 2011 2:20 am
by Kieran R1200R
Rolando33,
I had a R12S for about 18 months. I blinded it out with ever carbon fibre part possible.
The carbon wheels I have on my R12R wore for the R12S.
What happened was I put my R12S in to have a heated grip that was out with BMW under service warrenty.
They lent me a R12R for a loan bike.
From the moment I took it out of the service bay I noticed a incredible difference to the R12S.
It had low to midrange better power.
It steered quicker, and was more manuvorable in traffic.
I took it up my favorite roads and put it up there faster and with more confindence than on the R12S I owned.
So I was that imprest I traded the 12S on the R12R.
The carbon wheels on the R12R have less rotational mass so there for the pick up is quicker, the handling is lighter and the steering is razor sharp.
Personally I would put them on my R12R and forget about the R12S.
If I could clone myself and rode both bikes I would pass myself on the R12S because I am able to ride the R12R that much more quicker and more confindently. Also a big pluss I don't get sore wrists any more!
Re: Carbon fibre A Arm
Posted: Tue Feb 08, 2011 6:00 am
by dav
Rolando33 wrote:@Kieran,
Well, since you brought it up, what do you think about your carbon wheels? Did they help the performance? Durability? Price in Dollars or Euros? I have an R12S, and I would seriously consider those---the bling factor is way up there for that bike.
upload image
hosting images
WOW, great looking bike mate.
Re: Carbon fibre A Arm
Posted: Tue Feb 08, 2011 8:17 am
by Railbender
From my bicycle experience the biggest problem with carbon fiber components is that one scratch creates a stress point, and potential failure. I've got one recumbent bike with carbon fiber forks and I inspect them quite often.
Re: Carbon fiber A Arm
Posted: Wed Feb 09, 2011 2:28 am
by lewellen
mogu83 wrote:Maybe someone can answer this on carbon fiber. I have three bikes in the garage that are 30+ years old they are in good shape and just as serviceable as when they were new. What is the service life of carbon fiber when exposed to sunlight for years? I've seen carbon fiber body parts a few years old that look really ratty. I know that a lot of race bikes are loaded with the stuff but their service life is usually around five years.
I think they also use carbon fiber in aircraft, any pilots out there that have a read on that.
I'm hardly an expert, but here's what I learned.
Carbon fiber is basically the same concept as fiberglass: a laminated material consisting of layers of cloth (eg. glass or carbon fiber, kevlar, etc.) that're bound together with some form of glue (epoxy, plastic, etc.)
So: Four things that can go wrong. Poor lamination materials; poor binder; poor assembly technique; and improper usage (e.g. not what it was designed for). Carbon fiber aftermarket parts are often left unpainted because, let's face it, if you just spent a kilobuck to reduce the weight of your motorcycle by 0.25%, you want people to know!
If the binder isn't UV resistant (bad glue), it can discolor, degrade, weaken, or some combination thereof when left out in the sun. I've run into some that have a "matte" surface and feel tacky, that no amount of polish and wash can fix. If the mfgr. used a good glue but got the ratio of resin to hardener wrong, or did a bad job of mixing it, the same thing can happen. If you get the layering wrong, or use too much or too little binder, you can get a part that either flexes too much or is too brittle; in either case, it can start delaminating before its time.
I don't know of a good way to test beforehand whether a given part's going to resist UV degradation, other than through a forced aging test.
Re aircraft, ttbomk CF bits are starting to see use in a major way (Dreamliner, anyone?) but they're much more prevalent in small and military aircraft then they are in airliners. CF is popular with some experimental aircraft builders, but as a rule the aviation community is fairly conservative. The flex, stress and failure mechanisms are different than with metal structures, and there's still a bit to be worked out as to how you detect early damage.
For instance, you can see early-stage stress cracks in a metal aircraft wing. The CF equivalent might be some localized delamination, but there's a real good chance that won't be visible to the eye.
Kind of like the problem with dropping a helmet, when you think about it....
Good roads,
- Lewellen
Re: Carbon fibre A Arm
Posted: Wed Feb 09, 2011 2:29 am
by lewellen
Railbender wrote:From my bicycle experience the biggest problem with carbon fiber components is that one scratch creates a stress point, and potential failure. I've got one recumbent bike with carbon fiber forks and I inspect them quite often.
Well, you could take the approach early motorcyclists did with their torsion bars, and wrap them in tape....
Good roads,
- Lewellen
Re: Carbon fibre A Arm
Posted: Thu Feb 10, 2011 4:05 am
by Kieran R1200R
if you just spent a kilobuck to reduce the weight of your motorcycle by 0.25%, you want people to know!
Geeeeesss! that makes a lot of sence coming from a Scientist!!
Why don't you use your education and give the people fact rather than your mock!
Re: Carbon fibre A Arm
Posted: Thu Feb 10, 2011 5:17 am
by mvk
Geeeeesss! that makes a lot of sence coming from a Scientist!!
Why don't you use your education and give the people fact rather than your mock!
Hey Kieran -make like your bike and lighten up- it's great that you are passionate about your bike but CF ain't for everyone...
I grew up in the Adelaide Hills so I know what delights you have on your doorstep and you don't need a reason to blow off some steam - get out there on the Lobey run and, as you know, all will be right with the world.
Cheers mate
Re: Carbon fibre A Arm
Posted: Thu Feb 10, 2011 1:57 pm
by lewellen
Kieran R1200R wrote:if you just spent a kilobuck to reduce the weight of your motorcycle by 0.25%, you want people to know!
Geeeeesss! that makes a lot of sence coming from a Scientist!!
Why don't you use your education and give the people fact rather than your mock!
I did - and look at your reaction.
I wasn't taking a swipe at you - rather, human nature in general - so why so defensive?
Good roads,
- Lewellen
Re: Carbon fiber A Arm
Posted: Thu Feb 10, 2011 6:24 pm
by mogu83
lewellen - thanks for your plain language thoughts on carbon fiber. Thats the answer I was looking for, not a bunch of solemn high tech talk.
BTW: Human Nature
if you just spent a kilobuck to reduce the weight of your motorcycle by 0.25%, you want people to know!
I think I may be guilty, just went for new shocks, came down to three choices Hyper Pro (black or dark purple springs), Wilber (blue springs) Ohlins (Bright yellow springs that everyone in the motorcycle world knows cost big bucks). Guess which ones this victum of human nature went for.
