Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-27-06, 06:54 PM   #1
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
a question about suspension design

Now i was thinking, this'll probably end up with a million reasons why it wouldn't work, but what if you had a rear suspension design that pushed on the shock from both sides? Would that be feasable?
Blazinall91 is offline   Reply With Quote
Old 04-27-06, 07:11 PM   #2
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Bikes: 2014 Surly Steamroller, 1989 Nishiki Altron
Posts: 19,421
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Wouldn't do a thing.
Dannihilator is offline   Reply With Quote
Old 04-27-06, 07:20 PM   #3
mtnbiker66
Old School Rad
 
mtnbiker66's Avatar
 
Join Date: Sep 2004
Location: The old Mountains
Bikes: Blur LT
Posts: 8,212
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by KonaRider24
Wouldn't do a thing.
Yes it would. It would push on the shock from both sides. I'm so sick of you guys that know it all.............I'm going camping!
__________________
Like a circus monkey on a stolen Harley......
mtnbiker66 is offline   Reply With Quote
Old 04-27-06, 07:22 PM   #4
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Bikes: 2014 Surly Steamroller, 1989 Nishiki Altron
Posts: 19,421
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Quote:
Originally Posted by mtnbiker66
Yes it would. It would push on the shock from both sides. I'm so sick of you guys that know it all.............I'm going camping!
That it would but the benefits of suspension would be null and void. Unless the suspension design is like a linkage actuaded design like Giant's VT series was.
Dannihilator is offline   Reply With Quote
Old 04-28-06, 09:13 AM   #5
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
i ask because i had an idea for a suspension design floating around in my head and i was doing it with the shock being pushed on from one side and i realized it go either way, my design i have is sort of rube goldberg-esque but i think it has possibilities, I'll try to get a scan of one of philosophy class notebook renderings
Blazinall91 is offline   Reply With Quote
Old 04-28-06, 07:47 PM   #6
Dannihilator
User Title
 
Dannihilator's Avatar
 
Join Date: Oct 2002
Location: Annandale, New Jersey
Bikes: 2014 Surly Steamroller, 1989 Nishiki Altron
Posts: 19,421
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Even if it would work, there would be a hideous amount of chain growth.
Dannihilator is offline   Reply With Quote
Old 04-28-06, 08:41 PM   #7
pinkrobe
DNPAIMFB
 
pinkrobe's Avatar
 
Join Date: Aug 2005
Location: Cowtown, AB
Bikes: Titus El Guapo, Misfit diSSent, Cervelo Soloist Carbon, Wabi Lightning, et al.
Posts: 4,654
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
All shocks get pushed on from both sides. There's a force being applied to one end, and an opposing force on the other end. If one of those forces is missing, it's because your shock has nothing attached to it at one end. Now, what I think you really mean is that both ends are attached to parts of the suspension that pivot, perhaps a 5-bar linkage of some sort? The shock would act as a loaded frame member, or it could be leveraged by two separate arms or walking beams. I can see something like a three-shock system, where twin shocks [or one spring and one damper, or two dampers] above the rear axles compress, allowing a scissor-action on a third shock in front of the seat tube or whatever you would use for a pivot point. This abomination would give that third shock the squeeze for sure. Christ, that's ****ing ugly.
__________________
Proud Member of the HHCMF
'06 Cervelo Soloist Carbon | '09 Titus El Guapo | '09 Misfit diSSent | '09 Wabi Lightning
pinkrobe is offline   Reply With Quote
Old 04-29-06, 12:54 AM   #8
iamlucky13
Footballus vita est
 
iamlucky13's Avatar
 
Join Date: Jun 2002
Location: Portland, OR
Bikes: Trek 4500, Kona Dawg
Posts: 2,118
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
If all else fails (or better yet, as a starting point), use a free body diagram. I for one, can't figure out quite what you're talking about, but it sounds to my slightly (or seriously) inebriated mind that you're suggesting a linkage that connects to both ends of the shock simultaneously, and I'm not seeing something feasible in my mind's eye. How about a sketch?
__________________
"The internet is a place where absolutely nothing happens. You need to take advantage of that." ~ Strong Bad
iamlucky13 is offline   Reply With Quote
Old 04-30-06, 02:18 PM   #9
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
ok, it's about time to post a desgin sketch it seems none of you can read my mind, darn you all
Blazinall91 is offline   Reply With Quote
Old 04-30-06, 10:19 PM   #10
dminor 
Moar cowbell
 
dminor's Avatar
 
Join Date: Oct 2004
Location: The 509
Bikes: are awesome.
Posts: 12,429
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
I think I might have an inkling of what you are getting at, but I could be way off base. The first attempt at suspension on a bicycle I ever saw was on a BMX bike in the early '70s. It compressed the shock 'at both ends' in that it basically put the pivot in the bottom bracket and had a motorcycle shock between the seat tube and the head tube as the top tube. Very inefficient - - every stroke of the crank would have compressed the frame. Post your design sketches though . . . I'm always interested in seeing new (or creatively recycled) ideas.
__________________

Quote:
Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."
dminor is offline   Reply With Quote
Old 04-30-06, 10:27 PM   #11
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
this is what i have in mind.

kind of a rough sketch, should show the basic functioning of the design
Attached Images
File Type: jpg bikedesign.jpg (27.5 KB, 65 views)
Blazinall91 is offline   Reply With Quote
Old 04-30-06, 10:45 PM   #12
dminor 
Moar cowbell
 
dminor's Avatar
 
Join Date: Oct 2004
Location: The 509
Bikes: are awesome.
Posts: 12,429
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Very interesting. It shows the potential to let the shock 'float' inside the frame and give a lot of movement with a short stroke. I have two reservations about the design: the leverage ratio on a short shock; and it looks like the wheelbase may actually shorten as the suspension cycles through its travel.

Have you tried a cardboard mockup yet to check the rear wheel path? Use some chipboard and put a paper fasterner (or paper brad) at each pivot. Pin the 'frame to a cork board and cycle the design thru its travel and see if it acts the way you want it to.

Also, be sure to get the conversation going in the framebuilding forum. There's bound to be a lot of experience over there that can give you good pointers.
__________________

Quote:
Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."
dminor is offline   Reply With Quote
Old 05-01-06, 12:14 AM   #13
iamlucky13
Footballus vita est
 
iamlucky13's Avatar
 
Join Date: Jun 2002
Location: Portland, OR
Bikes: Trek 4500, Kona Dawg
Posts: 2,118
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'm not positive, but I think it has too much freedom so that the suspension could move without compressing the shock. Try the cardboard mockup, though. I know that Santa Cruz, and probably other companies do the same thing.
__________________
"The internet is a place where absolutely nothing happens. You need to take advantage of that." ~ Strong Bad
iamlucky13 is offline   Reply With Quote
Old 05-01-06, 02:17 PM   #14
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
my original design was the same as posted except with out the linkage from the upper arm in the rear to the shock. I just saw that making a sketch and wondered if it would work, I will make a couple cardboard mock ups of both and report back tell ya'll whats up
Blazinall91 is offline   Reply With Quote
Old 05-01-06, 02:45 PM   #15
born2bahick
Official Website Waterboy
 
born2bahick's Avatar
 
Join Date: Dec 2004
Bikes: a lot
Posts: 3,271
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Looks to me as though the scissor action of the design would slack the chain, If I'm getting the design right. Course I could be wrong!
born2bahick is offline   Reply With Quote
Old 05-01-06, 03:00 PM   #16
the wonginator
Shreddin' heaven on his 20"
 
the wonginator's Avatar
 
Join Date: May 2005
Location: markham, ontario, canada aka chinatown north
Bikes:
Posts: 1,151
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
draw it up in Linage www.bikechecker.com and let us know how it goes
the wonginator is offline   Reply With Quote
Old 05-01-06, 11:53 PM   #17
PSUfan09
Senior Member
 
PSUfan09's Avatar
 
Join Date: Jan 2006
Bikes:
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
that initially looks like the shock would just move forward when the motion starts, but that might just be crazy enough to work...if you make a rough free body diagram of the system it seems to work out- the forces are definately opposing on either end of the shock. the angles are a little goofy on that bottom section probably, which messes with ur head i think.

what if the shock was somehow fixed in place?

Just my $.02! i could be miles away though!
PSUfan09 is offline   Reply With Quote
Old 05-02-06, 09:54 AM   #18
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
do you mean like fixed but still have push from both sides
my initial design was the same except onlf pushing from one side
Blazinall91 is offline   Reply With Quote
Old 05-02-06, 11:24 AM   #19
PSUfan09
Senior Member
 
PSUfan09's Avatar
 
Join Date: Jan 2006
Bikes:
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Blazinall91
do you mean like fixed but still have push from both sides
my initial design was the same except onlf pushing from one side
yeah like have it mounted there, doubt that would work though
PSUfan09 is offline   Reply With Quote
Old 05-02-06, 01:11 PM   #20
Jason222
Banned.
 
Jason222's Avatar
 
Join Date: Nov 2004
Location: Moncton NB
Bikes: Trek Jack...trials bike soon.
Posts: 2,123
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I think it would work like it is.
Jason222 is offline   Reply With Quote
Old 05-03-06, 01:25 PM   #21
Blazinall91
Show Me What'cha got
Thread Starter
 
Blazinall91's Avatar
 
Join Date: May 2005
Location: O'Fallon, Misery
Bikes: old school Giant Attraction MTB (where it all started),old school Schwinn High Plains MTB (XC and long ride duty), Mosh DJ3 (BMX basher), and Trek Bruiser 1 (freeride and full of mods and still growing)
Posts: 1,225
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
i had to do some redesigning on it, after making a cardboard mock up the scissor action in the front severly limited travel so I'll post my new design soon
Blazinall91 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 02:36 PM.