Author [ES] [CA] [PL] [PT] [IT] [DE] [FR] [NL] [DK] [NO] [GR] [TR] Topic: General suspension thread  (Read 2623 times)

0 Members and 1 Guest are viewing this topic.

Offline thirdway

  • Street Triple God
  • *****
  • Topic Author
  • Posts: 6293
  • Bike: KTM 990 SMT
Re: General suspension thread
« Reply #10 on: July 02, 2008, 05:23:51 PM »
*Originally Posted by RedST [+]
:002:

like I said walk before I can run, I am still at first base and you are confusing me, or rather the way i read your posts

First each spring is different, then they are supplied the same  :087:


Every spring has a tolerance. Some might be 200lbs, some might be 220lbs. You can check the spring tolerance on a compression machine. This might be done at the Kayaba factory before the shocks are assembled, so that all shocks can simply be set using 'threads visible'. Alternatively, Triumph doesnt bother with that level of QC and simply sets them all the same........or, they actually set each machines static sag individually.

What I am saying is that unless you know that all the springs are exactly the same, the only way you can set up static sag is by measurement and not 'threads visible'.




*Originally Posted by RedST [+]
By increasing preload you increase the bikes ride height.......okay i get this..so if you carry a pillion or are XL the suspension is less likeley to flatten (or bottom-out) over big bumps.....surely this applies to!

Nope, the spring is exactly the same you have just compressed it a bit. You only increase the initial ride height because you no longer have the static sag. The only way to make changes to the spring rate is by fitting a different spring. Suspension is a compromise, even with a custom setup.



*Originally Posted by RedST [+]
The coment I was suggesting is that we each check so see what set up  comes from the factory, and I thought checking the threads would give us the information we need to see if they are all set the same

Unless you know that each spring is the same then the answer is NO. If you can guarantee that all springs are the same length and exact spring rate then YES.



*Originally Posted by RedST [+]
If we establish that they are all preset the same, then weight and road conditions can be next looked at, just to see whats best with the std/replace rear shock

I think you can take it they are all pretty much set the same unless triumph made a big mistake in the factory. You size the spring by spring rate based on bike+rider, then trim preload to give the right static sag.


*Originally Posted by RedST [+]
Maybe I should post these in the try out section for beginers, sorry for me, as the best way to get a specilaist shock, if I were ever to go that road (pun intended) would be to do as you have said before, tell the manufacturer you weight, type of riding and type of roads, that easy even for me, But I am not at that cross road yet, so just finding out info on our basic shock as it leave the factory, not that I am saying your information is not valuable, it is and will be looked upon later with nods of agreeemnt, just not yet for me till I get passed teh crawing stage

 :305:

You can actually change the spring on the standard shock, although the damping rate is so poor it will be swings and roundabouts. You are thinking if you tweak the preload its going to be better..........nope, it wont be unless your static sag is a long way out through factory error or, an incorrect or wildly out of tolerance spring.
"Be the change you wish to see in the world"

Offline Red

  • Street Triple God
  • *****
  • Posts: 17092
  • Carpe diem (na Kaapstad en terug)
Re: General suspension thread
« Reply #11 on: July 02, 2008, 06:12:05 PM »
 :002:

Nice technical info there thirdway

*Originally Posted by thirdway [+]
*Originally Posted by RedST [+]
By increasing preload you increase the bikes ride height.......okay i get this..so if you carry a pillion or are XL the suspension is less likeley to flatten (or bottom-out) over big bumps.....surely this applies to!

Nope, the spring is exactly the same you have just compressed it a bit. You only increase the initial ride height because you no longer have the static sag. The only way to make changes to the spring rate is by fitting a different spring. Suspension is a compromise, even with a custom setup.


you can see how easily I am confused. or rather lack of understanding, as my adapted quote came from the very article you were refering to in this month Bike mag

Still how wants a bike without character

 :305:
"Not just today"
"Vos es meus optimus amicus"
"We can't change the weather, only enjoy the challenges it brings."
"When the road gets rough, who needs tarmac? ;-)  X"
"Team Red Tours are go!"
"O" roads for the adventure
"Being quick is not about going fast,its about being slower less often"

Offline thirdway

  • Street Triple God
  • *****
  • Topic Author
  • Posts: 6293
  • Bike: KTM 990 SMT
Re: General suspension thread
« Reply #12 on: July 02, 2008, 09:00:19 PM »
*Originally Posted by RedST [+]
:002:

Nice technical info there thirdway

*Originally Posted by thirdway [+]
*Originally Posted by RedST [+]
By increasing preload you increase the bikes ride height.......okay i get this..so if you carry a pillion or are XL the suspension is less likeley to flatten (or bottom-out) over big bumps.....surely this applies to!

Nope, the spring is exactly the same you have just compressed it a bit. You only increase the initial ride height because you no longer have the static sag. The only way to make changes to the spring rate is by fitting a different spring. Suspension is a compromise, even with a custom setup.


you can see how easily I am confused. or rather lack of understanding, as my adapted quote came from the very article you were refering to in this month Bike mag

Still how wants a bike without character

 :305:

It confuses most people most of the time. I only got to grips with most of this through spending time with mountain bike suspension.

Draw a diagram of a shock absorber and it becomes clear what you are doing when you compress the spring using the adjusting collar. Ultimately if it takes say 1000Kg to compress as spring until it is coil bound it does not matter if the spring is partly compressed by adjusting the collar........1000Kg will still make it collapse to its maximum extent, its just the start point which alters. Theres no magic in it, its simple physics.

Just as important is the damping, you need the shock to compress in a way which allows it to cope with low speed bumps or braking forces and still give a good ride over smaller high speed irregularities. Thats your compression damping and on many bikes this is not adjustable, on othes there is a small envelope of adjustment.

Finally you have rebound damping (to some extent the weight of the bike + rider provides much of this). Once the spring is compressed you want it to return in a controlled way and as fast as possible.

In general, on a road bike there is little point in adjusting the damping beyond the basic set up. Thats because road bikes have to cope with an enormous variety of ever changing road conditions. Conversley, on a track, you can begin to adjust the damping for exact track conditions because of the shorter, known route. The suspension can then be set up more accurately to gain an advantage
"Be the change you wish to see in the world"

Offline Red

  • Street Triple God
  • *****
  • Posts: 17092
  • Carpe diem (na Kaapstad en terug)
Re: General suspension thread
« Reply #13 on: July 03, 2008, 09:02:16 AM »
 :002:

 I do get the principles of what you describe, so maybe you should inform Bike magazine of their error

Its just that you can read too much and believe what you read, only to read something to the contrary

Even what you read say things like,  the rebound was out but I thought it was the compression, or vice verser,

So back to the Street, we can only check the sag, and thats it

 :305:
"Not just today"
"Vos es meus optimus amicus"
"We can't change the weather, only enjoy the challenges it brings."
"When the road gets rough, who needs tarmac? ;-)  X"
"Team Red Tours are go!"
"O" roads for the adventure
"Being quick is not about going fast,its about being slower less often"

Offline thirdway

  • Street Triple God
  • *****
  • Topic Author
  • Posts: 6293
  • Bike: KTM 990 SMT
Re: General suspension thread
« Reply #14 on: July 03, 2008, 11:08:25 AM »
*Originally Posted by RedST [+]
:002:

 I do get the principles of what you describe, so maybe you should inform Bike magazine of their error

Its just that you can read too much and believe what you read, only to read something to the contrary

Even what you read say things like,  the rebound was out but I thought it was the compression, or vice verser,

So back to the Street, we can only check the sag, and thats it

 :305:

Yes, only the sag. It's unlikely that it would be different from bike to bike, but if you wanted to check it, unless you are 100% certain that every spring is uniform, then you cannot use the threads as a guide. Use the measurement technique outlined earlier.

A lot of riders get hung up on adjusting things. In many cases it is the riding technique that is the cause of suspension problems for normal road riding. Unfortunately IMO the ST has poor suspension and a chassis and engine that can easily cope with a far better set up. If you are the right weight, or use mainly smooth roads, or travel fairly sedately, or are an ultra smooth expert then the ST will work well.........this suspension is perfectly adequate and safe.........but it can be so much better for those of us who ride outside of the usual or are not as smooth as we should be.

Having a custom setup will not compensate for poor riding technique, its not a panacea for that, ride well and you can cope with a bike with a bendy frame and clapped out shocks. I watched a friend of mine hunt down a Ducati 998 and two Fireblades on the road to Hawes.......note that I was watching from behind as these guys were riding quickly  :008:.....when we pulled up at the Cafe, my mate was already inside and had ordered our coffee (good lad). The guys on the Blade and the Ducati were wide eyed at the bike that had passed them on a bend and left them for dust.....what was it ?

A 20 year old BMW K75 RT !!
"Be the change you wish to see in the world"

 


Recent Posts/Topics