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Discussion Starter #1
I tried to raise the ride height on my S4 ('01) this weekend and had a little problem. The top lock-nut came loose easily, but the bottom one (of course the one that's hard to get to) seems to be very tight. I figured it may have bonded to the shaft a bit since the shaft seems to be aluminum and the locknut looks to be carbon-steel.

Anyway, the next plan of attack I came up with was to back out the bottom shock mount (a shaft that comes out through the right hand side of the swing arm), but ran out of time. Looks like the best way to do this is suspend the rear end of the bike (tie downs to a ceiling beam in my garage) and back out that shock mount until the ride height strut is free and I can swing it up a bit into a position where I can get more leverage on it.

Has anyone run into this before? Am I on the right path here? Is there a short-cut or better way of doing this? Also, once I get the nut free, how much thread is in there for adjustment (... how much can I increase the rear ride height and still have enough tread imbedded for the strut to be safely connected)?

TX -- SB
 

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I talked to another lister about this a little while back, I'll have to dig a little and see where that thread is at.

Anyway, you're on the right track. I would remove the bolt attaching the strut to the rocker, also. That way you can have the strut up on the bench where you can work on it easier.

The leverage ratio on the rear suspensiion is about 2.2 : 1, so if you lengthen the strut by 0.10", ride height will go up 0.22".

I haven't had my strut apart, so I don't know how long the threads are. Myself, I would leave a minimum of 1.5 diameters of thread engaged in the strut. I think it's 10mm diameter, so I'd leave 15mm threaded in. If you're feeling frisky, you could go less, but it would make_me_nervous.

BTW, the lower rod end and jam nut are left hand thread, identified by the little grooves in the jam nut and on the hex on the end of the strut.
 

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It sounds like you are on the right track. Speeddog830 provided some great info on the subject above. I am planning on adjusting mine as soon as I get a chance to strap it to the ceiling like you did and pull out the bottom bolt. I have been too busy riding to try it out. I have talked to several people about this adjustment. No one that I have talked to has a very straight forward "how to" method that works consistently that doesn't include modified tools (i.e. grinder or a torch). If you take pictures as you precede it would be very helpful to all of us w/ adjustable tie bar linkage.
 
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Discussion Starter #4
Thanks for the info. By the way the strut is made I figured the bottom was threaded "reverse" and since I loosed the top first, I pretty much knew which way the bottom one had to go.

I'm not sure I understand the other part of your message though. If I don't know how much [total] threaded length is, how can I know how much to leave embedded (...or for that matter exposed)? Your ratio of embedded length with respect to diameter (of the threaded portion of the rod) sounds right from an engineering standpoint - even though the rod is exposed purely to axial compression, it's still a good idea not to "push it" any closer. Still, it would be nice to know how long in was so I wouldn't have to pull it all-the-way apart. I'm really just planning to pull the bottom mount out and rotate the strut up a little so I can get a good box-end wrench on it ... left in place I can just barely get an open end wrench on it.

Not to ramble on, but I see your bike is set up pretty close to mine. Do you find that your [elevated] bars shift enough weight off the front end that you are looking for ways to shift some back onto the front end? That's why I'm looking to raise the rear end on mine and drop the front end (forks up in the triple clamps) to help load the front tire. I have 1" Pro-Italia risers - and like the comfort, but want to tighten up the steering a bit.
 
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Discussion Starter #5
i adjusted my rear ride height on the bike, i didn't have problems with the nuts being stuck but it was a tight squeeze for the wrench though. i raised it 5mm at the rear linkage and lowered the triple a little less than 10mm on the fork. combined with heli mounts, clip-ons, and s&p rearsets the bike now has a pretty agressive stance. the stock bars will allow approximately the same drop but am not sure how the risers will affect that. i had to machine some relief on the heli mounts when i converted over to the clip-ons. when i start doing my own valve adjustments i'll take a better look at the linkage... right now i don't have a good feel for the length of thread currently in the hiem joint so just went the 5mm.

as to the 1.5 depth to width ratio... it's a good general rule that also ensures you have enough thread engagement to support axial loading also.
 
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Discussion Starter #6
MonstaS4 - Keep in mind, the only reason I'm planning to go through all that extra work, is because my bottom lock nut is too tight (or fused) to get free. This isn't how it's supposed to be! If that nut would have come free (like my top one did), this is a five minute job ... loosen top (normal thread), loosen bottom (reverse thread), put a wrench on the shaft itself (mine has a "flats" build into it, so you can get a wrench on it), and then just turn it the way you want to go. As you turn it the rear end will either rise up, or drop down - depending on the direction you turn. It's really a very good design and I think in my case was just a little squirt of anti-seize compound away from being perfect. Hopefully, your will work like it's supposed to.

Hope that helps. Also, depending what you're looking to accomplish, you can "drop" the front end by lowering the triple clamps down on the fork tubes (...basically, loosen all clamping bolts on the triple clamps and slide the forks upward, and then retighten). This also "quickens" steering, but remember, it also reduces ground clearance somewhat. Neither of these adjustments should be considered until you're
"sag" is properly adjusted. My first step is to make sure that both front and rear "sag" is correct (...I'm sure there are threads on how to do this if you're not already familiar). Then I set comp. & rebound to factory and ride. Once I get comp and rebound where I like them, then I start thinking about ride height --- don't get me wrong, I'm no Pro ... this is just how I've gone about things on my other bikes and I usually end up happy right about the time I get a new bike!! ;)
 
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Discussion Starter #7
MarkV - When you say you dropped 10mm on the triple clamps, how does that translate to the amount of fork that now protrudes through the top surface of your [top] triple clamp. In other words, if you look across the top surface of the top triple clamp, what's the measurement (in mm) of the portion of fork that extends above that top plane?

My bike's forks actually recess down into the top clamp by about 5mm and I thought that was pretty strange when I first noticed it ... but it sounds like that's how S4's come from the factory.

TX
 
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Discussion Starter #8
my forks tops were flush with the top of the triple from the dealership. i noticed a bit of clearance in the stock clamps when i took them off to check what i'd need for the clip on project. it was about 10mm flat to flat but the relief probably only allowed about 8mm realistically. so i dropped the triple to use up that room. later i had to lathe out the heli-bar adaptors so they would clear the fork tops as i had them set. so far i've been pleased with the geometry changes.
 
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Discussion Starter #9
MonstaS4 - Keep in mind, the only reason I'm planning to go through all that extra work, is because my bottom lock nut is too tight (or fused) to get free.
Well MonstaS4 and I just went to Ducman's. Since I have a wishbone i was not familiar with adjusting the tie rod..it was simple just threw it on a rear stand, and i think even if the bottom nut is difficult if you adjust the top first it will pull the rod away from the bottom heim joint nut...maybe it is still stuck for you, it seemed that way for MonstaS4 also, but once there was a gap the heim joint nut moved easy....just a thought, if you haven't tried it that way, it worked for MonstaS4.......
 

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Thanks for the info. By the way the strut is made I figured the bottom was threaded "reverse" and since I loosed the top first, I pretty much knew which way the bottom one had to go.

I'm not sure I understand the other part of your message though. If I don't know how much [total] threaded length is, how can I know how much to leave embedded (...or for that matter exposed)? Your ratio of embedded length with respect to diameter (of the threaded portion of the rod) sounds right from an engineering standpoint - even though the rod is exposed purely to axial compression, it's still a good idea not to "push it" any closer. Still, it would be nice to know how long in was so I wouldn't have to pull it all-the-way apart. I'm really just planning to pull the bottom mount out and rotate the strut up a little so I can get a good box-end wrench on it ... left in place I can just barely get an open end wrench on it.

Not to ramble on, but I see your bike is set up pretty close to mine. Do you find that your [elevated] bars shift enough weight off the front end that you are looking for ways to shift some back onto the front end? That's why I'm looking to raise the rear end on mine and drop the front end (forks up in the triple clamps) to help load the front tire. I have 1" Pro-Italia risers - and like the comfort, but want to tighten up the steering a bit.
Wasn't slagging you on your moto knowledge, just wanted to make sure you knew about the lefty thread on the bottom....

I was hoping you were going to "take the bullet" for all of us and pull the heim all the way out.... ;)

I did the CycleCats to get some weight off of my wrists and straighten my neck a little. That and so much of my riding experience is on dirt bikes. Being leaned forward so much with so much weight on my hands puts all of the crash alarms on hair trigger.

I may do a strut adjustment / triple drop at some point. My S4 is way sportier than any other bike I've had, so I don't feel any lack of responsiveness. From a stability standpoint, the taller bars are not an improvement, so more weight on the front end would be better. I currently don't have any ground clearance problems, and I've got 3/8" to 1/2" of "chicken strip" and I don't hang off much at all.

I'm currently trying to get the front fork settings squared away, and it's turning into quite a challenge. Most roads it's just fine, but it just seems to lock up on small high-frequency stuff. I've gotta get that sorted out first.

I'm not sure if my setup and bike preferences are very common...If I had my way, I'd stretch the swingarm about an inch, drop my pegs 1/2" and raise my bars 1/2", and swap in the wide-ratio tranny out of the S4R. And I still want to have more rear brake.
 

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Well, it is possible to take the rear end up too far. I have been playing around w/ the ride height tie bar and liked the rear end up/weight on the front way of riding so I wanted to see how high I could go without compromising cornering.

It ended up putting too much pressure on the chain wear plate and chewed it up a little bit, put a little knick in the swingarm and chewed up two of the mounting bolts. Oops!

Just an FYI for all of you that were interested in doing this free modification. Now I am sitting here waiting for a high wear part from Ducati, not riding.
 
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Discussion Starter #12
The problem you have could be attributable to a smaller front sprocket (14T?) ... I'm not sure if you changed front sprocket, but if so that would bring the chain a little closer to the top of the swingarm. When you raise the rear end that just makes matters worse since the centerline of the front sprocket is not the same as the centerline of the swingarm bolt ... therefore I would think that raising the rear end could cause the kind of problem you're talking about.
 
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Discussion Starter #14
the odds of the chain rubbing the bottom wear pad is pretty minimal unless you've got some serious driveline lash going. if i recall, the parts are identical so in a pinch, you could swap top and bottom chain wear pads to get back on the road.
 

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S4Strati, thanks for the input. The P/N are different but I will check fit and bolt pattern. It looks like they are mirrored, not the same.
 
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Discussion Starter #16
ah yes... you're correct. sorry if i got you excited with misinformation :(
 
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