Im going to be making my own composite frame, i was just wondering if any of the carbon frames from the uk are lighter than the kh or xtp frames. Im aiming for about half the weight of a kh frame. the legs and seat tube will be 3 oz, hoping i can make a crown under 5 oz, that leave 2 more oz for holders and im at half a kh.
I believe Roger’s cf frames are carbon legs and seat tube with aluminium bearing holders and crown, bizzarely enogh i actually first learnt to ride on his cf 20". Cf is strong but you have to be careful with it in some respects, Roger always wraps his frames up when moving them around, scratch or chip damage could cause a fatal crack. Because of this, I’m not sure how good they would be for a trials frame, because you’re going to drop it on sharp edges and the like every so often. I’m not even sure it would be that good for muni for anyone but roger, because he never falls off. Unfortunately i don’t know exact weights for his frames.
Saw somethign interesting at unicon you might consider, a guy had a cf muni frame built from 4 small diametre cf rods, with machined aluminium crown and bearing holders that clamped around them. This way he didn’t have to do any custom moulding or layup, and still had a sweet cf frame.
Well in this case, im using fiberglass. For two reasons, its slightly better for impacts than carbon fiber, and its cheap. Im going to rig it up so the legs and seat tube can be replaced easily, incase one snaps or a crack shows up.
no, not really
it has clamps that hold the rods in place?
hmmm
i have inserts for my arrows
they are freaking strong.
i might just go get some bolts that fit in the inserts(they are threaded) and bolt them to a square tube (for the crown)
and do the same for the seatpost tube, but i willl have to figure out how to clamp the seatpost in.
Using CF tubes…I’m not too sure how you would handle the bearing holders…but as the for the crown you could prob. use a mountain bike suspension fork crown. As stated, most CF tubes are not made for such applications. The cost and trouble of making a CF unicycle just doesn’t seem worth it to me…Cf is very fragile and can crack/chip easily. The CF you see on mountain bikes is made in special lay-ups made to be a bit more forgiving to impacts and to have just enough “give” to take the harshness out of the bumps. They also use special outer coatings that protect the CF(and make it heavier). It’s a great material to use if you are trying to make a specific shape that you cannot make out of a metal or alloy, or if you are trying to take harshness/vibration out of the ride. To make it strong in the right places takes alot of know-how, and equipment(for building and testing) that is out of reach for the average home builder. Keep in mind that you will more than likely have to make a prototype to test that will fail fairly quicky…working with CF is rarely a “one shot” kind of deal, it takes time and prototypes(and money) to tweak it where it needs to be. As for fiberglass…bad idea. If you are looking for strength and light weight, FG is the wrong way to go. In stronger layups it is very heavy, and *very brittle. I’d personally like to see a light weight chromoly build-up(fluted or butted tubes)of a trials street frame. Steel is far more compliant and less prone to to fatigue than an aluminum frame. You can ride a 50 year old steel road bike and it will still ride almost the same as it did when it was made…an aluminum frame would never last anywhere near that long(if ridden regularly). Bamboo(i know, sounds crazy) is another very strong tube…but once again not too good with heavy side impacts. I’d say if you’re looking to be able to say “I have a carbon fiber frame” to impress people, go for it. If your looking for a lighter frame that will hold up to abuse…stick with the KH or similar. Instead of focusing on the frame, why not try to build up your wheel lighter…butted spokes/lighter gauge spokes…you can even try titanium spokes…the grams will add up. Cut down your seat or try lighter foam. Switch to lighter pedals…there are other ways to shave grams than putting yourself through the headaches and cost of working with CF and FG. Good luck, it will be neat to see what you come up with if you go through with it…
From what i have read carbon fiber is more brittle and less impact resilient than fiberglass. Do you know of a website or page that displays fiberglass’s strength compared weight wise to carbon fiber?