Powered by Outside

Basic Full Suspension Types / Reference With Pictures

PB Forum :: Beginners
Basic Full Suspension Types / Reference With Pictures
Author Message
flag ohklee
O+
Posted: Feb 20, 2017 at 18:04 Quote
boyblue1973 wrote:
I like my demo FSR so much, but I have a question, for deep drop offs like this...I bottom out my rear sus and hit my bum on the rear tires, any suggestions.


[PV=https://www.pinkbike.com/video/447097/]

You may want to double check your coil weight assuming you are using a coil shock or have your shock serviced. If air double check your air pressure.
flag metaldoss
Posted: Sep 6, 2017 at 19:41 Quote
Thanks to try to explain the suspension systeme but you have a lot of mistake. The position of the shock influence only the wheelrate and didn't influence the pedaling zone.
flag ricardopatineto
Posted: Sep 18, 2017 at 15:24 Quote
Maybe you guys can give me a few hints..

Ps: notice how the orange Oring is not even close to the bottom, (it those cycle all the way when not on the frame) and the swingarm is not bottom out at the stop..
photo


I mess up my back really bad on a silly accident and now I have six ''skateboard' wheels instead of disc in my lower back so I'm force to ride one of this, actually is super fun in the corners, even on the woops at the skatepark, but not much fun climbing specially if is not solid ground..

photo

37 years riding mountain bikes, balfas, outlands, lawills, all lawills, intense M1, nicolai's, race mammoth for my country a few times, plus tons of work on motorcycle suspension (dakar bikes) bike team mechanic, tons of certs, and I can not figure out why the actuation is so lame..

Sure the swingarm is really long (almost 18'' in between the pivot and the rear hub) and it twist like a noddle to the point of changing cogs, plus the frame is also very prone to twist..
photo

I have tried every trick I know and also many I read or got suggested and nothing, clean, measure and make sure everything rotates effordless, readjust and test every possible adjustment and permutations on the shock, the Suspension just feels death and never provide full range of mothion and this is only taking about ''absortion'',, control and traction, a broom stick actually performs better (it really those I test it rigid)

I do have a bunch of shocks of similar dimentions but they are in storage (even a avalanche) but I had play with this rockshox and they are actually not that horrible, I have the feeling the issue is more with the suspension/linkage design..

Any insidefull guestimations will be very much apreciated..

Ricky
flag Grumposaur
Posted: Sep 22, 2017 at 2:28 Quote
My guestimate: because of the long lever of the real wheel and shock linkage and weight on the rear wheel I expect that you have quite some pressure in the air damper. It is also a short stroke damper. So it might be also a part the friction of the air damper: going to a coil might give more responsive behaviour.

I didn't check with software or anything, but it looks to me that the linkage is regressive: so to avoid blowing through travel you have to add more air than you would like it to have for a nice SAG and good initial stroke tracking of the ground.
I have the feeling that the triangle should be taller so that the pushrod between fork and triangle would be more vertical, compared to shown in the photo. (or move the lover mount of that pushrod more to the left, but that would only increase the leverage, and harder to get change than get 2 custom triangles).

There is this guy in youtube that makes video/animations on springrate, leverage ratio etc etc for MTB's. He might can do your bike, see if it is indeed regressive. Making it more progressive and a coil should give you much smoother ride.
flag ricardopatineto
Posted: Sep 22, 2017 at 6:14 Quote
Grumposaur wrote:
My guestimate: because of the long lever of the real wheel and shock linkage and weight on the rear wheel I expect that you have quite some pressure in the air damper. It is also a short stroke damper. So it might be also a part the friction of the air damper: going to a coil might give more responsive behaviour.
thank you for your insidefull comments..

The minute I get my box of shocks I'm going to install one of the vanilla's or the avalanche just as a proof of concept, then get the proper rate spring and start tuning..

[Quote]
I didn't check with software or anything, but it looks to me that the linkage is regressive: so to avoid blowing through travel you have to add more air than you would like it to have for a nice SAG and good initial stroke tracking of the ground.
I have the feeling that the triangle should be taller so that the pushrod between fork and triangle would be more vertical, compared to shown in the photo. (or move the lover mount of that pushrod more to the left, but that would only increase the leverage, and harder to get change than get 2 custom triangles).
[/Quote]

I'm kind of computer luditte but maybe I can give the software a try, is it a free system or a fancy with a licence..??

Regressive is how it feels, it just kind of stops half way and freeze solid, I was trying to make it work by tuning the shock but is pointless, I just don't know how to calculate the optimal linkage geometry..

[Quote]
There is this guy in youtube that makes video/animations on springrate, leverage ratio etc etc for MTB's. He might can do your bike, see if it is indeed regressive. Making it more progressive and a coil should give you much smoother ride.[/Quote]

Do you have a link to his youtube page...??

I have a small milling machine and made a few linkages over the years I just need to understand better in what direction I'm going, they are very simple flat plates so I just need to cut them and drill the bores..

Thanks again, the trike people think I'm crazy since I already have ''Suspension'' but I have been around shocks for a long time and I'm use to a certain standard that is just not there on the trike, not even in terms of ''shock absortion'' but as a ''traction enhancer'' is totally useless in fact detrimental..
flag Grumposaur
Posted: Sep 22, 2017 at 11:46 Quote
If it freeze solid in its stroke I would expect very high ramp up, thus progressive. But you need autocad or any 2d modelling software, maybe there is bike specific software for it, to give a definitive answer.

The guy is andrextr, his channel: https://www.youtube.com/channel/UCAicBI2QJNNrE2j_RkbzjYQ

I don't know what he uses, but you can contact him on FB aswell (I dont know him personally btw), also give him you weight, he might be able to determine springrate required:

His FB:
https://www.facebook.com/BTTveredas/
flag ricardopatineto
Posted: Sep 22, 2017 at 12:27 Quote
Grumposaur wrote:
If it freeze solid in its stroke I would expect very high ramp up, thus progressive. But you need autocad or any 2d modelling software, maybe there is bike specific software for it, to give a definitive answer.

The guy is andrextr, his channel: https://www.youtube.com/channel/UCAicBI2QJNNrE2j_RkbzjYQ

I don't know what he uses, but you can contact him on FB aswell (I dont know him personally btw), also give him you weight, he might be able to determine springrate required:

His FB:
https://www.facebook.com/BTTveredas/

Wow thanks, great places to start..
flag maxlombardy
Posted: Sep 23, 2017 at 13:55 Quote
Is that some kind of a Knolly?
flag ricardopatineto
Posted: Sep 25, 2017 at 6:02 Quote
maxlombardy wrote:
Is that some kind of a Knolly?

I Wish..
flag ricardopatineto
Posted: Oct 1, 2017 at 15:30 Quote
Any advice...??

I had watch a ton of videos from Andres (very smart dude for sure) and implement some of his concepts but sincerely not much of a improvement..

Next step to make my own linkage plates with tons of adjustability to play the ''cold & warm'' game until I find a set up that works better so it give me a direction to go so at least I'm not guestimating so much..
flag s8ntnick
Posted: Oct 23, 2017 at 15:19 Quote
andresextr might use "linkage design" software. Antonio Osuna has a blog with lots of bikes analyzed with this modeling tool for instance. His blog is here: http://linkagedesign.blogspot.com/ use google translate if english is needed.

you can download a free version also which has limitation of course.
flag ricardopatineto
Posted: Nov 13, 2017 at 16:38 Quote
s8ntnick wrote:
andresextr might use "linkage design" software. Antonio Osuna has a blog with lots of bikes analyzed with this modeling tool for instance. His blog is here: http://linkagedesign.blogspot.com/ use google translate if english is needed.

you can download a free version also which has limitation of course.

Gracias
flag Jake-G1
Posted: Nov 13, 2017 at 23:42 Quote
Little bit of help. I ride a whyte t130 (quad link 4/horst link) which is a similar linkage to specs fsr. I have replaced the rear air shock with a cane creek coil inline. To me it feels great on the bike however I'm no expert. Would you say this is a good combination, that linkage with a coil shock? As I'm aware that air is more progressive however I'm not sure if the linkage is progressive or linear...
flag chickenrunz
Posted: Feb 16, 2018 at 18:44 Quote
i have access to Trek Remedy (latest version) and Santa Cruz Bronson (latest version) -

which suspension is better in terms of freedom of movement under braking and small bump sensitivity?

 


Copyright © 2000 - 2024. Pinkbike.com. All rights reserved.
dv56 0.011875
Mobile Version of Website