Designing / machining a top triple clamp

[Daniniowa]

If anyone has any aftermarket top triple clamps, could you tell me how thick they are?

I have access to a large machine shop and supplies, and would like to design a new top triple clamp for me. I'm 6'5" tall, and the stock handlebar position is pretty crappy. I would like to move the bars at least 2" forward, and then find some taller bars.

T6 aluminum should be strong enough shouldn't it? I was thinking I'd start with a piece of bar stock between 3/4" and 1" thick.

 

[Jon K.]

Shouldn't the clamping area be at least as thick as the stock part? 1 inch is narrow.

 

[Jaybird]

between 3/4" and 1" thick.

so....7/8" tripple clamps?

 

[MikeT]

wfo is right. You need to measure how thick/wide the clamping area is and thats how thick a piece of aluminum you need to start with. If your mot sure of the auminum type, just call a few aftermarket manufacturers and see what they are using.

 

[SFO]

6061 is fine.
I can understand your enthusiasm to machine your own parts, but after working for shops that made billet clamps, and making a few of my own,
I consider my time to be more valuable. I would purchase an aftermarket clamp for a hundred bucks and make my own risers.
I am 6'8" and I run a protaper clamp with RC renthals.
If you go too far forward you will run into cable routing issues...

 

[Jon K.]

I always wondered about welding the upper fork directly to the trees and eliminating the clamp altogether. Should be very rigid and light. The next step would be to cast the fork and trees in one piece. The stem would remove like an axle bolt.
Any thoughts?

 

[motopuffs]

service?

 

[Jon K.]

Service would be no harder than present. Pull the wheel, disassemble fork or forks, remove whole assembly if needed. Piece-a-cake.
No pinch bolts to bind up the works!
Moving the forks in the triple clamps would be gone, but effect could still be accomplished via spacers on the stem.

 

[Daniniowa]

I did look, and the bottom side of my top triple clamp is recessed. It's not a solid bar design. It is cast with ribbing and recessed areas and then machined. So, I guess I could just make it out of a piece of aluminum that is as thick as the portion around the forks, and then it would be potentially stronger than the stock cast piece.

As far as casting the fork tubes and triple clamps together, some mountain bike front forks are very similar in design. I don't really see a disadvantage, maybe cost? Would casting and maching be cheaper than two fork tubes and two triple clamps? Rigidity would be high. While we are at this, how about building a single sided front fork like Cannondale's mountain bike fork?

I'm an engineering student, working as a co-op right now, so time isn't real precious. I have most of my evenings free. Being able to present this project to a potential employer in the future is precious.

 

[P_Taylor]

I put Applied clamps on my KX then machined my own bar mounts that moved the bars forward and up. The Applied clamps are 7075 where most others are 6061. I also mad the bar mounts with mounting holes for a Scott`s damper to sit behind the bar mounted backwards from the normal position.
Making the bar mounts instead of the top clamp leaves room to change it if you don`t get the position right the first time.

Thumper racing can custom make longer cables if you need them.

 

[Jaybird]

Dan,
I'm just curious...I see you are an engineering co-op and I was wondering if you actually have any machine tool experience? Unless you recieved training prior, I doubt that you learned any machine tool operation at school. If you have the skills required, then disreguard this, but if not...realize that there are many different set-ups and operations involved in machining even the simplist of clamps.
Designing this beast is one thing....machining it out of stock, is quite another.

 

[Daniniowa]

Thanks for the concern, and yes I do have some experience. I'm one of the few that has actually worked for a while, and then returned to college after taking some time off. I have been around mills and do have experience using them. Plus, Iowa State University's engineering program does put it's students in a machine shop for several classes and requires them to complete some projects.

If I need any additional help with something I'm not real familiar with, I can always ask the machinists at work for help with setup.

As far a handlebar mount placement, I was going to make at least two, and if possible three holes where I could place the handlebar mounts. Stock location behind the center of the fork tubes, in the center of the fork tubes, and forward of center of the fork tubes.

 

[Kizmen]

I commend you on your upcoming effort. I can't wait to hear all the facets you encounter in the middle of production. It's extensive to say the least. Good Luck.

 

[Neil Wig]

I personally think all engineering students should take on this type of a project. It may not be a money maker for him, but it will certainly highlight the differences between "looking good on paper", and real life manufacturing. As a Mech. Eng. Tech. with several years of machining experience, I have witnessed all array of engineering wonders that looked peachy on paper, but didn't work worth a crap. I fully believe that to be a good Mechanical Engineer, you need real, hands on, manufacturing experience. This level of experience isn't available in a one or two semester, spoon fed course.
Best of luck, it sounds like a great project, that you will learn volumes from.

Later