What does a DH bike need?

[Jaybies_Can_Crash]

Hello all,

I am a third year engineering student and, as part of a system design course, need the help of people in this forum.

I have do an analysis of the needs attributable to a product of some sort. I will then rank the needs, do a search of the competition for the prospective product and finally do an analysis of what trade offs are involved and what design goals would be realistic.

I have chosen a downhill mountain bike as my product (specifically the frame) and, while having a reasonable knowledge myself, need to consult with customers as to needs and improvements.


Therefore, what I would like the people here to help me with is providing input on:

What does the bike have to do? (e.g. manual easily, be stable at speed, be stiff in the rear end etc)

What do you like about current products on the market/products you use?

What do you dislike about current products on the market/products you use?

What improvements do you think could be made over the products on the market (I would like these to be moderately realistic, but any input is appreciated)?


Thank you all very much, just a quick response from a few people on any or all of the above points will make my life a lot easier, as you are the perfect customer base to "interview".


Thanks again,
-Jason

[The Paperboy]

ummm steel would be a good start. haha jks

good geometry would be one of the main keys, to make the bike as light as possible without compremising(spellcheck) the strength of the frame, headset angles have to be right for stability and crap like that. What do i like about products at the moment the way dhing is going towards internal gearboxing. With some love and care i think internal is the way to go. No more silly derailuers(spellcheck) getting bent half way down a run. Of course there are most probably set backs with internal gearboxing but i do not know to much about it but it sounds good to me. What i don't like, the fact that they don't stop you from falling off(ouchies).

Well thats my rant i'm not sure if thats what you want but i'm saying it anyways

bye bye

[red_dog]

Basicly you tend to find that only some of these atributes are present in any one build

Lightweight
Stiff rear design(what ever the design)
Good rear axle travel 'path'
little to no pedal feed-back
Adjustable head angle
Easily cleanable
Easily serviced
Bearing, pivots etc easy to replace/grease/service etc
A seat that can be lowered enough that wont touch the rear wheel..??

[little man]

yeh i agree with what you guys have already said, just 2 more things to add: some people buy bikes just because they look kool, but some buy them because they feel good(geometrey, specs) and also the price nto everyone can afford 9grand bikes.
thats my input, hope it helps

[Jaybies_Can_Crash]

Thanks for the input, for the three that have helped out.

Input in any form is very helpful, as part of the process is supposed to be analysing interview material to end up with actual technical specifications.

Thanks again, and if anyone has something to add, it will help immensely.

Cheers,
-Jason

[Superman]

Reliability - Something that will work week after week without a heap of maintenance.

[THE YETI]

Yeh, i agree with all the comments so far. But i would like to add that a low-ish bb height makes the bike ALOT easier to corner (ie switchbacks etc) and thay arent that much of a hassle in rockgardens. Also i would like to add that axle path is a VERY big issue. The patented Specialized FSR seems to work wonders. But there can be issues. (An example being the NZ based 2-stage bikes) have a problem with pedal jack on the bigger hits. (pedal jack- chain tension tightens and pedals cannot move) Just a suggestion that perhaps you should be looking at the axle path as a big part of your frame/suspension designing.