Rocky, rooty trail settings.

[yzguy15]

Thinks to self "Wow, if I only knew what these guys were talking about." Yall are really into some deep stuff! How'd you guys learn this?

 

[MACE]

Originally posted by Jeremy Wilkey:
Well I'm about usless on this topic

(Cough, cough.... mmmmmmmm....)

Originally posted by Jeremy Wilkey:

As for the dyno well we are actually in process of building one
Jer

Are you building one of the single stroke pneumatic jobs or a "scotch yoke" or something else? What about the valve "flow bench"? That might actually help in isolating and quantifying the effects or valve changes better than a dyno. Any idea what kind of operating pressures a flow bench that would require?


------------------
MACE

"Prime Directive - Serve the public trust, protect the innocent, uphold the law."

 

[James Dean]

Jeremy,

A dyno to figure out the variables sounds like fun stuff. I would also like to here about what special features you will have.

James

 

[Jeff Howe]

He has no hair currently. That what you mean by special features?

 

[Jeremy Wilkey]

The dnyo! Well we are looking at having a "yook" type with basically an electric motor driving a mast that is indexed in 2 locations. The moter will give us the ablity to drive it at virtually infinat (To a obvoius limit, so I had better say an infinant range with in a range.) And acelerate at any point so as to model linkage movement and multtiple sincarios. Obvously we will be runing this off a three phase electrical system and we are tring to figure what motor we will need right now. IT's a big deal beacuse we don't have three phase at the shop and will need to run a phase conveter so power lose is an issue.

As for the system we are seeting it up to have enought stroke to work with forks as well and hopefully we can work a motor speed combination that will get use in the ballpark. The sytem will measur postion and speed and interface with with a basic software package that we are writing the code for, or at least that is the plan. IT will be crude but the process is what I'm after. We want to have it done in a year.

As for the flow bench man I have thought about that forever!!! KXVET (PA SA)and I have been throwing that around and he thinks he can do something with it. Hes got some resources and I hope it will go somewhere. It's been my exspereince that many times things like this don't turn out as planed but seem to really educate along the way..

Regards,
Jer

 

[MTRHEAD]

JD- looking at the stack you put together, I'd tend to think that both Hi and Lo are both much softer. Are you getting a lot more dive or hanging lower with that set up?

I would also think that the LS stack is forced to do a lot more of the work now.

 

[James Dean]

Mtrhead,

The front does not dive or ride too low for my conditions. It does turn pretty good though in the tight stuff. The forks are slid up 5mm and the oil level was increased about 20mm. The LS stack is getting more work with the larger gap for sure. The most noticeable change is the reduced mid to high speed harshness.

It could probably be better, but I'm riding faster now than before in my favorite area.

James

 

[MTRHEAD]

This place needs more threads like this!

Where has everyone gone?

 

[yamadawg]

Mtrhead,

Here is my take.First what is the problem excatly.I the front end deflecting,harsh,I dont know so since I ride on alot of the same conditions here is what I would do.

1.Do your springs match your ride weight.if they are to light then the front end is going to already be into the stroke causing the forks to be harsh.you are already into the stiff part of the valving.

2.fork hight in the tripple tree will be the main factor in how the bike steers the higher the fork is in the tree the quicker the bike will steer.just the opp. when they are lower in the tree it will be slower.

3.if your in alot of muddy conditons then the more mud hince more weight and the bike ends up in the travel and creates harshness.

other than that suspension takes time,alot of time,to get right and you still have to plan for later race conditions..

Start out making small adjustments and do make to many at one time.keep a log on your changes so you know what is working and not working.Also try to keep your fork oil and shock oil as fresh as possible.

Also remember that usually you should adjust things just the oppisite from what you think.

It just takes time, I know that you dont have alot of it so good luck and hope that this helps...

------------------
it dont hurt till the bone shows.

2001 YZ 250

 

[JTT]

Originally posted by yamadawg:
you are already into the stiff part of the valving.

...please explain...


------------------
JTT
Logic Over Hype Coalition

 

[yamadawg]

if you are through the stroke than oil has already been pushed through the valve and shim stacks less travel left less oil=harsh ride.

------------------
it dont hurt till the bone shows.

2001 YZ 250

 

[Jeremy Wilkey]

Yamadawg,
What do you mean?
Jer

 

[MTRHEAD]

This was a prompting type post used to generate discussion, much like "derhwurm" and his "shim shuffle" or "4bangers" thread asking for opinions on his stack.

I'd just like to see more threads of that nature. I find them very interesting and enjoy reading the input from guys like Mace, Shocknut, JamesDean, MN KDXers, Marcus and others.

There are a lot of very bright folks here providing far more contribution than they are given credit. Without them things are pretty dull.

 

[Jeremy Wilkey]

Originally posted by MTRHEAD:

-- --- -----

MTRHEAD, Could you spell that out more clearly? I thought it might have said "so (Water flowing over bridge)-----
' but I could not get the last part... Just curious...

Regards,
Jer

 

[svi]

Originally posted by MN KDXer:
James D,


c) The shim stack does not open parallel to the surface of the piston orfice.

Following on from this I have often wondered how shims bend. With a 3 port piston do the shims bend in 3 planes ? I am guessing the 2 large ports on some Ohlins pistons will simply fold the shim. With a 4 port would that fold the shim, bend it up in a cone or would it just lift at the port opening ?

 

[Jeremy Wilkey]

Having whatched the patterns on shims and pistons for years i feel the stacks fold in planes along the edge of the port, and clamping shim. This cause them to crease in the oposite area. Many manufactures have placed lands that go out from the center of the radius to prevent them from folding inward..

Jer

 

[MACE]

BUMP!

Has anyone else noticed that a heck of a lot of great threads have floated off to oblivion? I've started to copy the good ones to Word files so they aren't lost totally. :(

Man, first I can't access from work, then a bunch of classics turn up missing and now we need to become paying members....

Perhaps the lack of archive space and the need for memberships are related problems.

MACE (trying to not flame.....)

 

[MTRHEAD]

Yes Mace, I agree. Very little good stuff here any more.

 

[Joe Turner]

Originally posted by MTRHEAD
BTW- -- --- ----- = in the click

If you are going to come in here and insult people at least have the courtesy to pick up a dictionary and spell the insult CORRECTLY . It's clique genius.

Rather than moan about the lack of content why not try PROVIDING SOME from your vast tuning background.

 

[MACE]

Sorry if I set a snippy tone to this thread.

I am just quite upset that the we only have about one month of archive here now. I probably should realize that the storage of the old posts cost money, but we've lost two years and thousands of posts of really good discussion.

I feel like the library burned down or something...

MACE (a sensitive, caring new-age Alan Alda sort of guy - with a Desert Eagle)

 

[MACE]

Bump once more. Please disregard the last few cranky sounding threads. :thumb:
:slap:

 

[Papakeith]

Honestly, I miss threads like this one. I was never able to really add any content, but they afforded me to think about my suspension in ways that I never would have otherwise.
Did you ever find the root and rock grail Mace?

 

[marcusgunby]

I tried to set up a thread recently concerning using midvalve lift as a method of tuning a fork to rider speed but with jer away and few others around it soon died.I have felt a bit lonely here ,JTT has kept me company but few others have joined the party:(

 

[Papakeith]

I've read the posts, but I don't have anything to bring to the table, so I generally just read it and move on. Maybe I could show interest by bumping it up, or just try to answer, and get b-slapped by the more learned suspension people here when I'm off-base. I'd love to see this forum come alive again.

 

[KTM-Lew]

Hey Marcus....I just happen to be doing an up-date on my forks. I had done an MX-Tech self-install when I bought my bike in Sept of last year. I intend to try a little experimenting with the float after I get all the new parts installed.

If I reveal too much Jer will have me shot but I'll try to participate. ;)