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Resident Raggamuffin
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Discussion Starter #1
i find the rear on the motorcycle to be "chattery," "stiff," and "slightly unstable" at speed over uneven surfaces but improved since a recent suspension clinic visit. i'm fortunate in that my friend "bromike666" has the same model year 999r so here are the pertinent and comparative stats from measurements taken today:

2003 999r "my bike"....i am 176lbs without gear

ohlins 1091-34-100
shock compressed to 10mm preload

-static sag = 6mm
-loaded sag = 28mm

compression: 17 clicks out (i clicked 17 times clockwise til it stopped)
rebound: 11 clicks in (i clicked 11 times counterclockwise til it stopped)

2003 999r "my friend Bromike666's bike"

ohlins 1091-16-64 (much softer spring)
preload: i believe to be 10mm as well

-loaded sag 20mm with ME on it (we didn't measure clicks of rebound or compression as i didn't want to screw with his settings whatsoever). he is heavier than i and achieves much better sag results given his additional weight.

So if our measurements were accurate, i was somehow able to compress his softer spring LESS than my stiffer one. he is able to compress my spring slightly more than i could (again, he is heavier).

everything about the two shock units, linkages, ride height adjusters looked/measured identical to one another, and our swingarms are the same as well. the only thing i couldn't determine were the shock type numbers stamped on the shock towers so to determine if one shock unit was in fact different than the other.

randy at in-house suspension felt that there was something peculiar about the way the bike responded during a recent evaluation (rebounded too quickly, too much gas in the compression unit which he reduced). he thought that the spring was too stiff for my weight. i spoke to Dan Kyle in great length about the subject at hand, and he was very kind in taking the time to walk me thru all of the measurements and the like. he thought that the spring was ok given the measurements i gave him. in the end, he could only opine that something was in fact different about the shock (regardless of spring) given the measurements that we gave him over the phone (and visual details of the corresponding parts). i was able to compress a softer spring MORE than the stiffer spring on my bike. for him to be able to recommend a better solution he'd have to either see pictures of the parts (my bike and bromike's 999r) or see the bike in person to evaluate it.

does anyone have any ideas of their own as to what might be wrong with my suspension? could it be the internals? is it just the spring that is too stiff, but then why could i compress my bike more than my buddy's with a softer spring? is it in the rebound/compression settings? i'd be surprised given that in-house suspension just adjusted it based on their findings (although they said to ride it then report back, which i did, and it was improved but not perfect).

thoughts?

thanks in advance :)
 

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Track -Day!!

Do a Track-Day that has a track side suspension service, have it set-up at speed, some of the suspension companys will work with you all day to get your bike right. If that dosn't work, send the shock out for a rebuild. Aloha Alex

PS: or you can ride your Hyper more..............:D
 

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Resident Raggamuffin
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Discussion Starter #3
thanks Alex, appreciate the suggestion, and you're right, the HYM/MTS will see more time until i get it sorted out. let's ride soon!
 

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comrade moderator
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The only thing that caught my eye was the rebound settings. You mentioned they were measured from "out". Both compression and rebound should be always be measured from all the way "In".

But that's neither here nor there and the compression and rebound have nothing to do with preload settings. Comp and rebound control the speed the shock operates at, not the stiffness or force.

So...my only guess is you have a mis-labled spring. I've heard of it happening. I don't know the Ohlins codes off hand, but I wonder if buying a known spring would solve the problems. Or sending your spring to Dan or somebody who could measure it.
 

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In terms of ride height, did you compare the rear only, or both front & rear? Maybe the bikes don't have the same F/R weight bias (fork position / steering angle).
 

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Clearly #176 is just a superior bike to #183, yours must be a Friday build:D

Seriously, I think we should swap 999r's on this Friday's ride and compare ride notes.

Psst.......... it's Obie's B-Day Friday and we're doing a morning ride.
 

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Resident Raggamuffin
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Discussion Starter #7
Thank you, Chuckracer. Your thoughts make me think that replacing my spring with a softer one ( I happen to have a 1091-26/85) could be the least expensive and quickest test to see if that is the fix. If the sag measurements/ride don't jive at that time then perhaps the internals or shock unit itself need to be adjusted or replaced.
 

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Resident Raggamuffin
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Discussion Starter #8
In terms of ride height, did you compare the rear only, or both front & rear? Maybe the bikes don't have the same F/R weight bias (fork position / steering angle).
Thank you as well for your response. We compared rear only, and in full disclosure, we don't purport to be suspension pros, but we can install our own battery tenders :) As you allude to, the only way to get this properly sorted out is to have it re-examined once again in closer detail. Perhaps a much better rider will say that i'm smoking crack and that it's the best tuned bike on the mountain.

time will tell i suppose but i'm certain of one thing, crack killz. ;)
 

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Resident Raggamuffin
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Discussion Starter #9
Clearly #176 is just a superior bike to #183, yours must be a Friday build:D

Seriously, I think we should swap 999r's on this Friday's ride and compare ride notes.

Psst.......... it's Obie's B-Day Friday and we're doing a morning ride.
you had to didn't you. as if having to ride with one sneaker right now isn't embarrassing enough!!!! :eek:
 

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Hey Oalvarez,

Putting spring rates aside for a moment, it sounds like you are overdamped in the rear, and maybe the front. One thing that's weird in suspension tuning is that often times what feels like a "rear" problem stems from the front, and vice-versa, so look at the front settings too for sag.

If you turned your compression damper 17 clicks clockwise you are starting at fully loose and adding compression damping. If you turned it until you hit the stop you are at max compression damping, which will almost for sure make it feel harsh. This is a frame of reference only, but both my Ducatis (with Ohlins rear shocks) are set up toward the soft side of the compression range, maybe 4-6 clicks in from full soft. A bit of an apples and oranges comparison, but it's something to check. Maybe turn it full soft, then back in 4 clicks and see what happens. I remember seeing an article in Motorcyclist once that suggested for rebound damping to start with it set so that when you push down on the rear it takes about a second to return. Again, a place to start, but this has worked for me.

Your rear sag numbers look in the suggested range in the article attached. Take a look at it, and have fun tuning. Personally, I think an intelligent and informed owner, with some time and experimentation, can do a good job on set-up for a street bike. My 955 had supposedly been set-up by a suspension pro for a rider close to my weight, and it was awful, ran wide in corners, and felt choppy through corners. Just by following the basics in the Ohlins guides I made huge improvements. If I can do it so can you. The experimentation gives you a good excuse for a ride too.

http://www.ohlins.com/Checkpoint-Ohlins/Setting-Up-Your-Bike/Underrubrik_1/
 

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Duc ... Duc ... GOOSE!
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I'm sorry to hear you're still having trouble. Last time we rode together you mentioned the issue; I thought The Clubhouse Think Tank :think: (the three of us) settled on your needing a softer spring.

Sounds like Kyle's thinking the same thing...

PM me with Friday's ride details, Bike Swappers.


PS: Don't listen to Tye.
 

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Ok well since I've been through this process numerous times in the last week, I can probably aid slightly.

#1 Your rear spring rate isn't proper. It should be 90nm or -29 (ohlins part#)
#2 Your static sag/rider sag is a tiny bit off. You should be able to get 5mm OR LESS of static sag and 30mm +/- 2 rider sag.
#3 You want LESS rebound, not more... The stock valving on those shocks blows and most of the time you have to run the rebound out. This goes for
the compression too, most of them need to have the compression jacked up.

Your spring is actually probably either perfect or too light. You're valving is whats causing the problem now and without re-building I'm afraid you're not going to resolve anything. Take the shock off the bike, send it to Dan Kyle and have him re-build it. You do know that after 2 years, the oil is no good in those shocks or forks. Your bike is slightly older then 2 years... ;)

Once you get it back from Dan, then you can start messing with it. I can almost guarantee you, the fixed shock will be nothing like it is today. At the same time, I'd send the forks up to him as well and have him install the updated valving into them and of course, have the oil refreshed.

Then, hit up a track day with Randy or the local guy from Catylist Reaction or even Dave himself. Either or, you need somebody to tune in the bike for you, it will help a great deal with resolving problems like you have.

My 2006 749R shock is toast as well, it only has 2600 miles on it! So I can feel your pain, but its worth doing it right and not wasting anymore time.

Gooc luck!



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Just for infomation purposes, I have 999R bike #189, meaning its newer and therefore in better shape. My spring is 1091-16/64 L242. Those numbers mean absolutely nothing to me though. Hey Obie, as long as your sorted out before myself and another 999R buddy get down there, June now. Heres the latest pic. BTW, I have a once in a lifetime opportunity to purchase parts made by Beringer. Likely the bling hi tech king of brake systems.
 

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It is like a XX9R club meeting in here. I second the vote for having the shock rebuilt. The OEM Ohlins use junk for internals. Sure it is better than the others OEM stuff but it is nothing like what the true aftermarket R&T stuff gets. Send the forks and shocks off to get the good stuff installed. I had it done on my Aprilia and it is butter now.

The coolest thing is that when you stop a little harder than average, you can hear the oil swooshing through the valves:)
 

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Ok well since I've been through this process numerous times in the last week, I can probably aid slightly.

#1 Your rear spring rate isn't proper. It should be 90nm or -29 (ohlins part#)
#2 Your static sag/rider sag is a tiny bit off. You should be able to get 5mm OR LESS of static sag and 30mm +/- 2 rider sag.
#3 You want LESS rebound, not more... The stock valving on those shocks blows and most of the time you have to run the rebound out. This goes for
the compression too, most of them need to have the compression jacked up.

Your spring is actually probably either perfect or too light. You're valving is whats causing the problem now and without re-building I'm afraid you're not going to resolve anything. Take the shock off the bike, send it to Dan Kyle and have him re-build it. You do know that after 2 years, the oil is no good in those shocks or forks. Your bike is slightly older then 2 years... ;)

Once you get it back from Dan, then you can start messing with it. I can almost guarantee you, the fixed shock will be nothing like it is today. At the same time, I'd send the forks up to him as well and have him install the updated valving into them and of course, have the oil refreshed.

Then, hit up a track day with Randy or the local guy from Catylist Reaction or even Dave himself. Either or, you need somebody to tune in the bike for you, it will help a great deal with resolving problems like you have.

My 2006 749R shock is toast as well, it only has 2600 miles on it! So I can feel your pain, but its worth doing it right and not wasting anymore time.

Gooc luck!
Tye, How can you possibly know it needs re-building from reading any of the above? Writing a check to someone to "fix" the problem through a track-side set-up does little if anything to help the owner learn. How is an expert at a track going to know how to set up a bike for an individual with individual riding style and weight distribution? I would also ask, how is it you know more than the factory engineers at Ohlins? Ooopps I forgot, you do of course.

Do you know what critical damping is and what the significance is? Didn't think so, at least not without googling it.
 

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Tye, How can you possibly know it needs re-building from reading any of the above? Writing a check to someone to "fix" the problem through a track-side set-up does little if anything to help the owner learn. How is an expert at a track going to know how to set up a bike for an individual with individual riding style and weight distribution? I would also ask, how is it you know more than the factory engineers at Ohlins? Ooopps I forgot, you do of course.

Do you know what critical damping is and what the significance is? Didn't think so, at least not without googling it.
You really don't know that oil lasts 2 years? Ohh and that ducati OEM products are shipped with limited valving adjustment because if some idiot were to crank up the valve all the way and the shock STOPPED moving, who would be sued?

Here is what the OP said; just incase you missed it:
oalvarez said:
randy at in-house suspension felt that there was something peculiar about the way the bike responded during a recent evaluation (rebounded too quickly, too much gas in the compression unit which he reduced). he thought that the spring was too stiff for my weight.
Ya wanna know why a bike would re-bound too quickly? If the oil was totally shot and it was just running off the spring. I've met a lot of suspension guru's before and Randy is not what I'd call one of them.



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Wow, the R meeting just turned hostile.

The first thing to think about is that the oil in the shock is very old so you know it is not going to perform like it should. Get that out of there and while it is apart take the shit valves out and get the good stuff in.

http://picasaweb.google.com/35MotorSports/Suspension#5282076977552931378

This is what your oil looks like from the factory with only 1K miles on it. Do you think the people in the factory are worried if the parts are clean on the inside?

http://picasaweb.google.com/35MotorSports/Suspension#5298617983604055954

I don't have my pic handy that shows the OEM R&T parts to the other stuff so I will have to steal 35motorsports.com 's pic. These are two completely different parts but the look nearly identical. The left of this pic is from a jap bike but is nearly identical to the OEM R&T. On the right is from GP Suspension. The GP suspension has larger holes (the six showing) than the Ohlins. When I was researching getting the kit installed I heard from a few people that said they drill their Ohlins holes out a little more than they come in the kit. I didn't do it since I didn't have the specs on how far to drill them out but I am sure Dan would know what to do.

Also, tell him how and where you ride. Your suspension will be setup different if you are on the track or on the street. Let's be honest, you can go fast on the street but on the track you are really pushing it to the limit. You want your suspension to be setup to work properly at the speeds you will be going.
 

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Chilehead
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I have nothing to add of any value to this thread except that I agree with MarkG and Chuck and all this talk of ride swapping brings these guys to mind.
Ride swapping is good, I do it all the time.

Last weekend I let my friend take my 999R, and I got his heavily modified R75/5 (really a R90S in sheep's clothing). He liked the ORAM rebuild of my suspension (we traded last year, me getting his 916SPS that time), but not the BT016 tires, which I agreed with, so I went back to PP 2CTs today. The BT front was totally dead after 4k km, and the rear was also to the wear bars.

Tom
 
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