carbon fiber/aluminum frame

[unicyclerman]

Originally Posted by scott ttocs

I am a bit confused about the point of making a Carbon Fiber/Al frame. Is the goal to make it stronger than current frames or to make a lighter unicycle? I am sure that they would look very cool, which may be reason enough.

How often do people break KH Al frames? Is this an ongoing problem for Trials riding? Do people ever break CrMo frames?

My impression is that the frame is so small for most unicycles compared with a bike, particularly for a 20" or 24", that the material used is not going to make a huge difference in the overall weight of the unicycle. I may be wrong. How much does a KH Al frame weigh for a 20" trials unicycle? Is it 2 Kg? If you cut that down to 500 g that would be a savings of 1.5 Kg, but I am not sure if that weight is possible with the Carbon/Al hybride. If you went from 2 kg to 1.5 kg, the overall weight savings would be small for the whole unicycle.

It seems like all the other components add a lot of weight. Has anyone put together a list of all the components and their weights? If you want a 20% lighter unicycle you could go down the list and try to save weight everywhere. For example, the seat and the rubber tire would appear to add a significant amount of weight to a trials unicycle. Can you shave weight off those components? I realize that there is a difference between the spinning components (angular momentum) that will change the handling of a unicycle and the non-spinning components such as the seat.

How much difference does the weight make? I understand that a Torker DX is very heavy and that a KH 20" trials would be lighter. Does this change the feel of the ride? Does it make some moves, such as hops, easier? I have no experience with this type of riding.

I am tossing out these questions because I do not know the answers and would be curious about the reasons for going to a much lighter unicycle. I admit to being a bit cynical, in part because of the weekend bicycle riders I know who buy very light high-end bikes for mucho $$. They spend another $1000 (or much more) to shave 2 kg off the bike. I cannot help but notice that they could just as well shave more than 2 kg off their tummys and the whole bike and rider package would be lighter. In theory, the 2 kg of fat are free. (In the spirit of full disclosure, I could also loose 2 kg of fat with sufficient motivation--the fat is certainly there waiting to be lost.)

Back to the main point. Are you trying to build a lighter unicycle frame or a stronger unicycle frame? Can you save enough weight on the frame to make a real difference to the overall weight of the unicycle?

im hoping for lighter and stronger. though i dont think it realy needs to be stronger not many people break frames alot. lighter deffinately makes a difference. with lighter weight the uni is just easyer to handle. you dont have alll that weight weighing it down. i also just want to see some more diversity in the market. for the most part all cromos look the same and all alu frames look the same. so i want to get a new look and material out there. if i cant get them to be lighter than a KH then i wont sell them for as much as a KH so there would be a good light and cheaper frame out there as well. also i custom make them so i can suply people with custom length long necks. im running this like a mom and pop shop so no extra charge for custom dimensions except if you want a 36er i gotta cover extra material.

[unicyclerman]

hey sorry it took a while. this is the progress we have made on the frame. it does not have the weight cut ins on the top bar and the sides are twice as long as they are supposed to be but even so it only weighs about 350g. we still need to put in the neck support, neck piece, or bearing races, but we are expecting it to remain under 500g maybe as low as 400g and feeling it now i dont think there will be any problems with structural integrity. we are working on getting oval tube instead of the round tube we are using right now but for now this is what we got. we are also trying to get more roundover on the top. so let us know what you think so far. keep in mind its still very much under development, this is just the progress we have made.

[Smilymarco]

NICE!

Looks good

[uniaddict]

Yay! Someone who actually followed through with their frame plans.

[joeking36]

thats groovy as! i would rock it. sent one out to aus i'll test it for ya! haha. but on a serious note i hope you followthrough with this cause i would consider it at a reasonable price obvously. it looks pretty mad!
by the way what is that carbon fibre worth for a tube like that?

[munirocks]

Looking good! I actually have a cf frame made be Roger Davies ten years ago. It didn't crack or anything, although I have been pretty cautious with it too. I only use it for moderate XC riding. But I think the frame is very robust and ultra light. Would be interesting to make a 36" frame like that, maybe with a rounder crown, oval tubing and magura mounts. Or maybe something like a V-frame? I would love to try that.

[ntappin]

That looks really hot. Do you have bearing holders yet? I would love to see what they look like if you do!

[unicyclerman]

the bearing holders are next on the list. we didn't have time to cut them out before we left utah. im thinking that they will be similar to the KH bearing holders. they will be tapped and have an allen bolt that goes through the bottom. I havnt seen the design they have worked up yet. but once they get them done I will post more pics

[skrobo]

hmmm
this is a pretty sweet deal you have going here.

[drumstuck]

Well done on getting this far. I have seen enough to know I will be a potential customer for a coker frame if you get to the finish line.

What is the outside diameter of the tube just out of interest?

[drumstuck]

Might be worth finding out what is needed to make the dropouts schlumpf compatible, someone on here will know. I can possiby dig out the answer - let me know. Also, if it is possible to add the facility to fit V-brakes/Maguras might be worth looking into at this point. PACE do a carbon fork and sell a brake mount that fits this as a spare part, btw. It has to be fitted with a torque wrench so as not to damage the CF, but if the OD of your tube as it passes the rim is the same, and not ovalised at this point, then you will have the option to add brakes. I will get you the OD of their fork if you want.

[unicyclerman]

we are working on getting the 20 " frame first then once we have that we are going to make coker frames and such. as long as the distance between the bearings is the same we should just need to make the legs longer. i need to get a coker wheelset before we can move into this however. so if anyone has a decent 36 wheelset they are willing to part with for cheap let me know. when we do the 36 frame we are definitely going to try and set it up for magura brakes we will just have to wait till we have a wheelset to set it up with. oh and if i remember right the OD of the tubing is about 1.18".

[Smilymarco]

Any new infos on this stuff? Cant wait for the full frame with weight and stuff.

[pedrotejada]

Originally Posted by Smilymarco

Any new infos on this stuff? Cant wait for the full frame with weight and stuff.

+1!

But just a tip: Your design may not work for trials street and flat! Riders wants a really small tire clearance and a frame where you don't hit your legs.

If the top of the crowns is too big for sure that will happen.

Just as reference: Some top riders used a file on XTP frames, cause they were hitting the knee on the serial number! An it was like 2 or 3mm bigger...

Go for it, since the best part is learning how to work and the pleasure of riding it, but if you want to sell it in the future, may some improvements will be nice!

Bye and Keep us updated!

[unicyclerman]

ya i kept telling them to make it smaller but when someone knows more about engineering it is verry hard to convince them. but we made some tweeks to the design and i am verry pleased with how it has turned out. the bearing holders should be finished today but the final design for the crown is done. so i will get more pictures up when its all the way done. ive also been working on a company name/ logo thing. me and my brother are starting this together so for a company name we were going to do Erickson brothers unicycles or just EB uni for short. what do you think?