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Airmail109
10-19-2007, 07:12 AM
Im asking this because you guys are a bit more intelligent than the guys on the MTB forums, who are very superstitious.

With current technology is Carbon any weaker than Aluminum? I'm asking this because I'm considering getting a Carbon Framed All-day Cross country bike to compliment my monster 35lb+ downhill rig.

This is the bike Im thinking of getting, an Ibis Mojo. All the reviews of it have been amazing, literally not one complaint even on the forums. Apart from riders who have a superstitious hatred for carbon.

http://www.ibiscycles.com/mountain/

Theres a bit on that website about Carbons durability, have a look at it tech heads and see if it checks out.

TgD Thunderbolt56
10-19-2007, 07:18 AM
The newer carbon composites (and the resins that are used to bind them) are incredibly strong, resilient and have a higher tensile strength than most aluminum alloys.

Your question is relative, to a degree, because there are differing degrees of carbon composite strength and differing degrees of Aluminum alloy strength...but personally, I'd grab the carbon.

TB

The-Pizza-Man
10-19-2007, 07:20 AM
no, the stiffness and strength of carbon fibre composites are generally higher than aluminium.

LEBillfish
10-19-2007, 07:24 AM
Imagine when someone decides to try spinning "aluminum fiber" and then weaving it like carbon http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Airmail109
10-19-2007, 07:31 AM
Oki thx guys! I trust the advice on here a little more http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif Done quite a bit of homework, everything seems to check out http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

Any difference in how they fail, is Carbon Fiber going to explode on me as opposed to crack at the welds\bend like Alu?

Not that Im going to be doing extreme stuff on it, but Im used to flying along at stupid speeds on my downhill rig...kind of a habit. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

They use Carbon Fiber in the f-22, I think that seals it for me tbh.

MEGILE
10-19-2007, 07:36 AM
Originally posted by Aimail101:


They use Carbon Fiber in the f-22, I think that seals it for me tbh.

you'll be stealth http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Daiichidoku
10-19-2007, 07:44 AM
if CF was good enough for Chief Tyrol, then its good enough for me

http://img.photobucket.com/albums/v479/Daiichidoku/blackbird.jpg

space_bandit
10-19-2007, 07:50 AM
The main thing about a carbon MTB would be how likely you are to ding the frame. Carbon won't stand as much damage as aluminium. What I like about carbon is the stiffness (road bike) I'm not sure with rear suspension you would feel the difference over Al.

Airmail109
10-19-2007, 07:57 AM
Originally posted by space_bandit:
The main thing about a carbon MTB would be how likely you are to ding the frame. Carbon won't stand as much damage as aluminium. What I like about carbon is the stiffness (road bike) I'm not sure with rear suspension you would feel the difference over Al.

Good point, I wont be riding at silly speeds on it anyway. Never dented a frame bar one spectacular crash in the Alps downhilling that would have ended any bike. Ill probably put a heavy duty mud guard on the bottom tube to protect against flying stones. Also the frame has a lifetime crash warranty, so Ibis will repair any small dents If I happen to get them http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

I'm mainly going for a Carbon full-sus frame because it means I can have a light enough bike for big uphills, and a bike with plenty of suspension travel (6 inch front/5.5 rear) and strength to enjoy the descents. On stiffness, you can lock the rear suspension out on the climbs, and I would feel it on the descents. Stiff frames handle so much better on them.

The long-travel all mountain bikes tend to be around 31lbs in weight, and they don't tend to be the stiffest bikes compared to my beefier downhill rig. Lightweight aluminum full-sus XC bikes are even worse. And hardtails make it hard to walk after a 50km ride. Carbon seems to solve all this, your looking at 24/5lb for a "durable" build Mojo as opposed to loads of lightweight parts. And its stiff.

Id LOOOVE a nice road bike as well, but alas I cannot afford it yet! http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif What bike are you riding?

A question for you, my dads getting his first road-bike and seems set on the idea that a stiff road frame will be uncomfortable for big rides? Any ideas on this!

icrash
10-19-2007, 09:40 AM
I know a guy with a carbon Giant NRS - loves the heck out of it. The carbon will usually tend to dampen some of the vibrations coming into the frame as opposed to an Al frame which tends to transmit them. The carbon will usually crack or fracture first although I've heard of a seatpost breaking in half. (I don't want to know what the heck this guy was doing at the time.) As for dad's roadbike, hard to say. He might look into a carbon frame (good balance of stiffness & comfort). Depending on the budget, a titanium frame wouldn't be a bad choice either. It's sort of a comfort ride of a steel frame with the stiffness of the aluminum. It would have a longer lifespan than the carbon with the advantage that tubes could be replaced in the event something happened to it. Depending on the brand, look into the sport roadbikes. The geometry is tweaked for a more comfort ride.(longer head tube & wheelbase usually) It isn't as agressive as the race geometry bikes.

Loco-S
10-19-2007, 09:51 AM
I work for a living on Carbon fiber ( I assemble, repair, modify aircraft prototypes made of 3k bal 190 Carbon fiber) the material is very stiff, dampens vibrations, BUT is quite fragile under impacts, if you have a delamination be prepared for a very expensive repair ( man hour wise), for the same price I would go for Titanium frame.

Airmail109
10-19-2007, 10:13 AM
Originally posted by Loco-S:
I work for a living on Carbon fiber ( I assemble, repair, modify aircraft prototypes made of 3k bal 190 Carbon fiber) the material is very stiff, dampens vibrations, BUT is quite fragile under impacts, if you have a delamination be prepared for a very expensive repair ( man hour wise), for the same price I would go for Titanium frame.

You cant really get hold of titanium full sus frames. The frame Im looking at getting has been designed so that the last few layers of weave are more impact resistant then ontop of that the bike is reiniforced with a layer of E Glass. Its got a Lifetime crash warranty on it as well. So Im not really bothered about impact durability, an impact hard enough to cause any real damage to a this frame would most likely ruin all but the burliest aluminium bikes.

Thx for the the advice anyway Loco-S and Icrash have taken both into consideration, and will mull on it further!

XyZspineZyX
10-19-2007, 10:13 AM
Originally posted by Loco-S:
I work for a living on Carbon fiber ( I assemble, repair, modify aircraft prototypes made of 3k bal 190 Carbon fiber) the material is very stiff, dampens vibrations, BUT is quite fragile under impacts, if you have a delamination be prepared for a very expensive repair ( man hour wise), for the same price I would go for Titanium frame.

What brand? Cytec? I've been using a 6K AS4/epoxy prepreg unitape for a few years and it's pretty good stuff, but then again we also braid that at 45* to get the bias we want, and then lay THAT up to whatever schedule they engineer

You should check out a company called Albany International. They bought my old firm. They still market an ultrasonic insertion process that we used to do, in which staged or even un-processed c/f preforms and layups have Z-directional carbon-fiber pultruded rods, to not only combat delamination, but it also supports the part after failure (typically when anything breaks it's "failure" for those not in the biz)- the destructive tests will show the intial failure, but then the part can be brought back up to a certain percentage of it's initial strength without failure. It sort of screwed up a lot of test schedules over at NGC http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif Good stuff. They pultrude their own Z-fiber pins so you can customise your resin/fiber matrices to support almost any application. This process is in use right now on F/A 18 E/Fs. The ultrasonis move the fibers apart, no drilling or reduction of weight or anythign like that

I wouldn't buy a c/f bike frame. I've been stabbed with c/f WAAAYYYY too many times for that! Saving a few pounds total weight....we did some work with Trek once, and it seemed to me they would use a layup almost like fiberglass mat with lower quality stuff, then use a nice looking top layer to finish it off. Maybe that was just the prototyping stage, I dunno, but my point is that you can't see what the layup is...it could be [0,0,0,0,0] and how would you know?

Anyway, Albany International. Z-fiber instion, UAZ 1000 (UAZ is "Ultrasonically Assisted Z-fiber insertion") should be the handheld unit. Check them out. Ask for Jim Sims, he should still be the production guy over there

Airmail109
10-19-2007, 10:17 AM
Originally posted by BBB462cid:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Loco-S:
I work for a living on Carbon fiber ( I assemble, repair, modify aircraft prototypes made of 3k bal 190 Carbon fiber) the material is very stiff, dampens vibrations, BUT is quite fragile under impacts, if you have a delamination be prepared for a very expensive repair ( man hour wise), for the same price I would go for Titanium frame.

What brand? Cytec? I've been using a 6K AS4/epoxy prepreg unitape for a few years and it's pretty good stuff, but then again we also braid that at 45* to get the bias we want, and then lay THAT up to whatever schedule they engineer

You should check out a company called Albany International. They bought my old firm. They still market an ultrasonic insertion process that we used to do, in which staged or even un-processed c/f preforms and layups have Z-directional carbon-fiber pultruded rods, to not only combat delamination, but it also supports the part after failure (typically when anything breaks it's "failure" for those not in the biz)- the destructive tests will show the intial failure, but then the part can be brought back up to a certain percentage of it's initial strength without failure. It sort of screwed up a lot of test schedules over at NGC http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif Good stuff. They pultrude their own Z-fiber pins so you can customise your resin/fiber matrices to support almost any application. This process is in use right now on F/A 18 E/Fs. The ultrasonis move the fibers apart, no drilling or reduction of weight or anythign like that

I wouldn't buy a c/f bike frame. I've been stabbed with c/f WAAAYYYY too many times for that! Saving a few pounds total weight....we did some work with Trek once, and it seemed to me they would use a layup almost like fiberglass mat with lower quality stuff, then use a nice looking top layer to finish it off. Maybe that was just the prototyping stage, I dunno, but my point is that you can't see what the layup is...it could be [0,0,0,0,0] and how would you know?

Anyway, Albany International. Z-fiber instion, UAZ 1000 (UAZ is "Ultrasonically Assisted Z-fiber insertion") should be the handheld unit. Check them out. Ask for Jim Sims, he should still be the production guy over there </div></BLOCKQUOTE>

"Most of the layup of our carbon frames finds the carbon prepreg in 0º, 22.5º and 45º orientations. The 90º weave you often see as the top layer provides the best resistance to impact. We also add a layer of e glass in impact prone areas that need additional toughness."

These bikes have been on the market for two years now and no problems! Trek are not renouned for an eye for detail, these guys are! Ill get in contact with the guy you mentioned I reckon!

Thanks dude!

Loco-S
10-19-2007, 10:32 AM
I work with Toray composites, pre preg carbon between 3k and 12k for airframe composite structures, also with pre impregnated fiberglass as a sacrificial surface, cant tell much of our process as I have a NDA signed at work, some of our structures have as many as 60 plies on 0, 45 and 90 degrees, also wet lay up on dry weave carbon, with Epocast resin matrix, and hysol as substrate bonding for assembly of fuselage parts all of that is set with computer controlled temperatures and pressures, recently I got into a position of trainer for the company ( on call) to train people on high and low temp repairs, scarf repairs, and critical structure repairs ( say wing spars)and let me tell you, that stuff is high stress ( for me) one mistake and 40,000 bucks or more goes to teh dumpster, is fun to work with, but the price is full concentration ( zen while grinding away .001 of an inch at a time by hand)

after all that I have decided that Aluminum or titanium are the way to go.he he.

Airmail109
10-19-2007, 10:54 AM
How they build their bikes....I found the last bit interesting

"The terms low, medium and high are relative terms referring to modulus. Modulus is a reference to stiffness, which doesn't always correlate to strength. In the case of the bike industry the terms are somewhat misused. Typically bicycle industry folk use the term "high modulus" to refer to T800 or T1000 Toray fiber, as opposed to the more commonly used (in the bike industry) T700 fiber. In real terms all three materials would be considered high modulus with even T700 having a modulus of 33.4 msi. The higher modulus materials often come with a compromise in terms of tensile strength or elongation which means that even "high modulus" frames using T800 or T1000 are really a blend of T700 (which has the best overall mix of characteristics) with small amounts of the higher modulus stuff in areas where additional stiffness is required in a super light frame. However, there are no hard and fast rules here, so a company could call just about any composite material high modulus depending on what they're comparing it to.

The Silk and Mojo are blends of various fibers, but the frame is primarily T700. Until very recently, T700 was the best you could get, and still in terms of overall performance it is the best all around composite material available. Interesting side note: T400 a commonly used lower grade of composite actually has a higher modulus than T700, but its tensile strength and elongation numbers are worse. Also, T700 is a finer filament so a sheet of T400 UD prepreg would have a higher resin content that would compromise its strength further. Nonetheless, it could rightfully be called "High modulus"."



"In an effort to help you cut through the smoke and mirrors and preponderance of gobbledy****, we have decided to prepare for you a no-nonsense primer on carbon technology. We've noticed that there is a lot of hype about certain products, and a lot of claims of superiority in one way or another. In our opinion, there are a lot of great carbon fiber road bikes out there. We've all got geometry pretty well figured out. Most of the carbon bikes you can buy ride well. In other words, not a lot separates all of us, and we're not going to trash talk anyone. Not in public, anyway.

Why are we doing this hardcore soft sell? We feel that telling our customers the truth is what's most important. So, without further chest-beating, here's what we know about carbon fiber.

The word "composite" literally means "made of several parts". In a carbon fiber composite structure the parts are the: the reinforcing fiber generally we're talking about carbon, but it could be glass or Kevlar, and the resin. Carbon composites derive virtually all of their strength from the carbon filaments within the composite, but those filaments are nothing without the resin that binds them together in a matrix. A major factor in high quality carbon composite bicycles becoming a reality has been the advancements in the manufacture of both carbon filaments and resins over the past decade. In terms of carbon filaments, the tipping point has been the ability of manufacturers to produce stronger filaments. The tensile strength of the filament used in most high end frames is rated at 500 ksi (thousand pounds per square inch) or better though some manufacturers still use filament that is 10% weaker. Fiber filaments are also rated by their modulus stiffness and can be referred to as either being low, intermediate, or high modulus fiber, or by a measurement of the tensile modulus of the material expressed in msi (million pounds per square inch) or ksi. The strength and stiffness of carbon filament do not always correlate with each other. As a result, the design of a composite structure has to balance these two attributes in order to optimize the performance and durability of the finished product..

Like we said though, the filaments are nothing without the resin. And advancements in low viscosity resins have enabled reduction in the volume of resin used in a given composite and consequently increased the concentration of carbon filaments increasing the strength of the structure. The resin needs to be able to flow through the filaments and coat them evenly a process called "wet-out". With filaments as fine and tightly compacted as are found in modern composites it's easy to imagine how little microscopic gaps between the filaments could be left dry. Those voids can lead to fiber separation and failure, and like the bits of pasta on your plate that don't get covered by the sauce, nobody wants that.

Bike manufacturers usually start with carbon composites in one of two forms prepreg or tubing. Carbon composite tubing is basically pre-cooked in a generic form that allows the manufacturer to cut the tube to size and glue it into lugs that can be made a variety of materials including: carbon composite, steel, titanium, and aluminum. This method of construction can provide more leeway as far as building with custom frame geometry. However, lugged carbon construction doesn't allow the builder nearly as much choice of tube shapes and sizes as a monocoque, which can result in extra weight and material and concentrates stress at the weakest points of the frame the bonded joints.

Prepreg, the other main way of using composites, is short for "pre-impregnated", and it refers to a sheet of filaments pre-impregnated with uncured resin. The prepreg is adhered to tack sheets like the backing on shelving paper so that it can be more easily handled. Properly handled sheets are stored in freezers to keep the resin from curing prematurely, and in production the sheets are cut and laid up in climate controlled clean rooms by people wearing bunny suits to keep them from becoming contaminated.

To give bike frames their structural strength manufacturers employ a variety of unidirectional carbon fiber prepreg sheets. Each sheet is designated by the fiber orientation as being either a 0?, a plus 45?, a minus 45?, and/or a plus or minus 22.5?. Each orientation bestows a different mechanical attribute to the structure. 0? sheets develop build strength along the length of the structure. Plus and minus 45? sheets resist twisting, and the 22.5?'s fend off crushing loads. Together they determine the strength and stiffness of our little mechanical structure.

Another word you'll here often when researching composite bicycle frames is. Monocoque - meaning "a structure in which the shell bears most of the stress"- composite frames are molded using layers of prepreg in a very specific sequence and orientation. In practical terms, this means that large components of the frame (like the front triangle) are formed as a single integral piece. If properly designed and built, this unified structure distributes dynamic stress over a wider portion of the moncoque instead of creating areas of stress concentration at the joints as in traditional frame manufacturing. Monocoques also allow the Ibisians more creativity in the forms they can design. Which - on the whole - delivers you a lighter, stiffer, and more stylie (in our humble opinion) ride.

The sequence of prepreg layers is called "the lay-up schedule", and is determined by a variety of methods. Lots of folks talk about how they employ FEA - finite element analysis - to develop their schedule, but what they don't tell you is that FEA is only as good as the person who sets up the analysis. And the more complex the form or the material, the more difficult it is for FEA to give you useful information. Composite materials and the interesting forms it allows are very complex. We use FEA to develop the basic lay-up schedule, but then the artistry comes in. Engineers at our factory build up sample frames and test them over and over until they find just the right recipe' that mixes the appropriate amounts of strength and stiffness at the lightest total weight.

Now we come to the cooking. A critical aspect of composite manufacturing is the skill of the workers actually laying up the prepreg according to the lay-up schedule and the quality controls built into the manufacturing process. This is to insure that every frame meets the strength, stiffness and weight goals for that design.

Sections of the frame are layed up by hand around silicone forms according to the schedule. This process must be followed precisely to ensure the desired final result. Controls are integrated into the process to ensure that the sequence is followed and that just right amount and type of material is used. After the lay up is complete, the silicone form is removed and the components are set into a big, heavy steel mold. These components are laid up in an ingenious fashion (someone else figured this out, not us) so that the fibers from the various components overlap and become one unified structure when cured. Air bladders are inserted into the completed layup, the mold is closed and then inflated to roughly 150 psi. The large steel mold is heated for about 40 minutes at about 220 degrees Fahrenheit. This causes the resin in the prepreg to "wet-out" and then harden. When fully cured the separate components integrate with each other into a single monocoque structure.

Once the cured frame is removed from the mold it goes through many hours of hand finishing to give it a smooth surface, ready for paint or clear coat. But that's not the end; every Ibis frame is tested for strength and stiffness in several ways and must meet our specifications before it leaves the factory. To our knowledge this type of testing is unique in the bicycle industry and insures the quality we're after.

As you can tell, the process is a lengthy one, and only a few frames can be made per day. That keeps our production capacity fairly small. This is okay with us, as we want to keep our priorities straight (Ride More, Work Less) and get out on our bikes now and again."

HerrGraf
10-19-2007, 10:18 PM
A couple of years ago, I saw a bike that was made almost intirely out of bamboo. (Only the gears and gear change mechanism was metal.) Talked to the builder and he told me that it was very durable and light. Some bambo has a very high tinsel strength. Unfortunately I do not have any photos of it, but it was very clean and stylish.

berg417448
10-19-2007, 10:29 PM
Calfee makes a bamboo bike:

http://www.calfeedesign.com/bamboo.htm

VW-IceFire
10-19-2007, 10:33 PM
Not that its 100% the same but the new Boeing 787 Dreamliner has carbon fiber wings.

Here's a great quote about that:



Boeing has completed static testing of a three-quarter wingbox, but engineers are still considering whether to limit testing of the full wing to a 150% load limit held for 3 sec. of to continue bending it to see when it breaks. "There's a raging debate within the engineering team to see if we should break it or not," says [787 General Manager Mike] Bair.

Breaking it isn't necessary for certification, but Bair says the wing is so strong and flexible that there's been talk that maybe it could be bend far enough for the wingtips to touch above the fuselage"or come quite close.
http://blog.wired.com/wiredscience/2007/06/the-new-boeing-.html

So...should be pretty good stuff if done right. Solid but flexible at the same time.

Toten_Waffe
10-20-2007, 04:13 AM
Originally posted by Aimail101:
Im asking this because you guys are a bit more intelligent than the guys on the MTB forums, who are very superstitious.

With current technology is Carbon any weaker than Aluminum? I'm asking this because I'm considering getting a Carbon Framed All-day Cross country bike to compliment my monster 35lb+ downhill rig.

This is the bike Im thinking of getting, an Ibis Mojo. All the reviews of it have been amazing, literally not one complaint even on the forums. Apart from riders who have a superstitious hatred for carbon.

http://www.ibiscycles.com/mountain/

Theres a bit on that website about Carbons durability, have a look at it tech heads and see if it checks out.


I have had a number of bikes over the years and am seriously into road cycling (not so much mountain biking any more) but all of the components that have let me down have been carbon fiber.

Hed Tri-Spoke - Clincher rim separated from carbon body.

Corima Rear disc wheel - Rear hub body came loose from carbon body.

Easton EC90 Carbon handle bars (140s worth http://forums.ubi.com/images/smilies/bigtears.gif) - carbon delaminated when STI levers twisted during a small crash.

Trek 5500 road frame - Bottom bracket shell broke loose.

Most of the problems I have had are where the aluminium load bearing or threaded components that are glued to the carbon have broken loose.
Im not a heavy rider (73kg) but dont have 100% confidence in a lot of the carbon components I still ride with. I use them cos' they are very light and look cool.

If you want a descent XC hardtail I would go for a Lightspeed or Merlin titanium frame as the build quality is excelent and you can feel safe throwing around the rocky stuff.

Jagdgeschwader2
10-20-2007, 05:42 AM
That Mojo SL is a beaut! The price however is more than I'm willing to pay. I'll guess I'll continue lugging my old GT around. She's not as heavy after I upgraded her, but she's not light either. At least I can dodge all the crazy automobile drivers without having to wory about breaking anything on the bike. I've yet to experience the dreaded GT frame crack at the seat post that I hear so much about. Then again I'm usually cranking instead of sitting. Let us know how that carbon bike turns out.

http://home.earthlink.net/~jagdgeschwader26/sitebuildercontent/sitebuilderpictures/1121214.jpg


http://home.earthlink.net/~jagdgeschwader26/sitebuildercontent/sitebuilderpictures/jagdgeschwader2s3.jpg

Toten_Waffe
10-20-2007, 06:21 AM
My current race bike....Cannondale, with full dura-ace except for FSA carbon cranks, easton carbon bars and USE carbon seatpost, zipps or kysiriums depending on the circuit. http://forums.ubi.com/images/smilies/inlove.gif

http://i8.photobucket.com/albums/a20/toten_waffe/CannondaleZipps2.jpg

Jagdgeschwader2
10-20-2007, 06:31 AM
That is a work of art my friend! Looks fast sitting still. http://forums.ubi.com/images/smilies/11.gif

http://home.earthlink.net/~jagdgeschwader26/sitebuildercontent/sitebuilderpictures/jagdgeschwader2s3.jpg

Taylortony
10-20-2007, 06:34 AM
There are some serious issues in using carbon Fibre in Aircraft. One main one is the problems in a crash, Carbon shatters into millions of little shards.

I was still in the RAF when the first Harrier went into a wood, the crash and smash team on the scene walked around in the dust of the remains unprotected as no one knew....... It is worse than asbestos when inhaled... within months several of the members of the recovery team had dropped like flies....... one lost over 55% of his lung capacity as the hard fibres literally shred the lung linings as your lungs work, and there is NO way of removing these fibres.... Last one that went in in Germany saw the Engineers running away from the site.. bad bad stuff.....

An Airline near me had a strike on an Airbus horizontal Stab by a catering truck requiring the replacement of both at 2,000,000 a pop.. they donated them to an World renound Aircraft Engineering University in the UK.. I was speaking to a friend there and he told me they were going to section them....... I pointed out the info from the Harrier incident, they immediately stopped, checked up on it then carried it out in full suits and under controlled conditions ensuring no dust of fibres remained....... I do like to think I possibly saved someone that day from serious Injury.



As for the dreamliners.. well http://www.pprune.org/forums/showthread.php?t=292713&highlight=dreamliner

icrash
10-20-2007, 09:37 AM
Never ride down stairs with the seatpost too high while in the saddle. I've seen a guy do it and crack the frame at the seatpost. He lucked out cause we mananged to sweet talk a warranty person into sending a new frame. All of the GT bikes before the date when Pacific Cycles bought GT have lost their warranty on the frame.

Toten - tell me you didn't snag Mario's bike when he wasn't looking. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif