steering dampner mod
- Thread starter dewie
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IG.
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80W gear oil is like 20w or 30w motor oil. 90W gear oil is like 40w - 50w motor oil. See the chart a few posts above. I think gear oil is more suitable for the damper than motor oil properties wise. It's like you wouldn't put motor oil in your forks, but rather gear oil, right?
suzuka1980
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hmm....will it be more cost effective to purchase an aftermarket steering damper instead?
a couple of dollars to mod your existing damper vs. 500 for a aftermarket you define cost effective?
coreywiley
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Now that's what I call good info
This depends entirely on whether or not a crash ensues!
Installing a high dollar steering damper is no different than buying high dollar suspension. If it's not adjusted properly, it's no better than the stock unit.
IG.
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I did the 90W mod in late 2005, probably shortly after I fixed the bike after the infamous tankslapper. Since then, I put on more than 20k miles of aggressive riding, and did something like 10 - 15 track days. I ride year around, and rode in winter including rides at 20 deg, and well below 32, and of course during summer. This also covered a lot of rough pavement in and around NYC where the front needs to follow the imperfections of the road surface. This also included nemerous short 1st gear wheelies, even during winter time, not all of them landed absolutely perfectly (i.e. the front was not absolutely straight when the wheelie was landed, not excessively crooket - just a few degrees). This type of riding, including track days, was no different than prior to my tankslapper.
I honestly could not tell the difference tha damper was there with 90W gear oil. I know it's not a scientific data, but based on all this, my assessment is that the damper with 90W gear oil is far from being stiff to become a danger for normal riding - danger in a sense that when the front needs to move back and forth in order to adhere to road's imperfections and is not able to do so because the damper is too stiff.
This was my concern when I was doing the mod, so I did experiment with the damper when it was off the bike (see my previous detailed posts) just to get the feel how the oil affects its behavior. The damper was noticeably stiffer when off the bike and trying to move it by hand, especially after I put it in a freezer (simulating winter conditions). However, when I put it on the bike where the handlebars provide better leverage vs. moving the damper by hand off the bike, it did not seem that stiff at all.
Only when I lifted the front off the gound, grabbed both handlebars, and tried to move them side to side as quickly as I could, I did notice some resistance, but not excessive.
I am also positive that during normal riding the damper resistance is still many times smaller than your normal effort to steer the bike, and that is why I could not notice the extra resistance to turning was there with heavier oil.
Also keep in mind that a damper - primitive or advanced - is not a cure for the rider mistakes. Prevention is the ultimate cure most of the time, and when that fails or impossible, it's the damper which saves the day. IIRC, I posted very detailed thoughts on that in my earlier posts.
It's like the best suspension in the world won't help a rider making abrupt inputs, and in the wrong places. And that is the reason I never upgraded my suspension. I am trying to improve my riding focusing on smoothness, body position, correct timing and precision of my inputs, etc. and interpreting feedback from the bike, and I feel the stock suspension is working just fine. When, if ever, I reach the level when the suspension is the limiting factor, only then it would be time to upgrade.
I honestly could not tell the difference tha damper was there with 90W gear oil. I know it's not a scientific data, but based on all this, my assessment is that the damper with 90W gear oil is far from being stiff to become a danger for normal riding - danger in a sense that when the front needs to move back and forth in order to adhere to road's imperfections and is not able to do so because the damper is too stiff.
This was my concern when I was doing the mod, so I did experiment with the damper when it was off the bike (see my previous detailed posts) just to get the feel how the oil affects its behavior. The damper was noticeably stiffer when off the bike and trying to move it by hand, especially after I put it in a freezer (simulating winter conditions). However, when I put it on the bike where the handlebars provide better leverage vs. moving the damper by hand off the bike, it did not seem that stiff at all.
Only when I lifted the front off the gound, grabbed both handlebars, and tried to move them side to side as quickly as I could, I did notice some resistance, but not excessive.
I am also positive that during normal riding the damper resistance is still many times smaller than your normal effort to steer the bike, and that is why I could not notice the extra resistance to turning was there with heavier oil.
Also keep in mind that a damper - primitive or advanced - is not a cure for the rider mistakes. Prevention is the ultimate cure most of the time, and when that fails or impossible, it's the damper which saves the day. IIRC, I posted very detailed thoughts on that in my earlier posts.
It's like the best suspension in the world won't help a rider making abrupt inputs, and in the wrong places. And that is the reason I never upgraded my suspension. I am trying to improve my riding focusing on smoothness, body position, correct timing and precision of my inputs, etc. and interpreting feedback from the bike, and I feel the stock suspension is working just fine. When, if ever, I reach the level when the suspension is the limiting factor, only then it would be time to upgrade.
Messy but that's how we did it.
Munchie
Registered
Sorry guys but this is the first I've ever heard of this topic but so far, has me very interested. At the same time, I must say that I don't have major complaints with my existing stock setup so I have to ask, what is the motivation to make the change? Is this just to kill the tankslapper possibility? Or do you guys like the steering response better after the change?
Next set of questions...so stock is 5WT gear oil? ...or is it specifically fork oil? and how does fork oil compare to gear oil? or can you buy heavier weight fork oil?
Just after reading through the VERY informative posts...the general concensus on posted averages has been between 40 to 90WT? Also seems confusing that stock weight is 5WT but most that reported changing to 30WT noticed no difference? So how does the stock fluid compare to gear oil?
Seems like a HUGE jump to me...???
I'm entering the phase of "suspension curiosity" so this is interesting and completely foreign material. I will point out that I have never had the opportunity to ride a tuned suspension, so if this is a "You'll know it when you feel it" type change, I could appreciate that aspect.
BTW, if it makes a difference, I'm 5'10" 205 dressed out on a stock K8 suspension (other than front being lowered 1.5" - plan to raise the back 1")
Next set of questions...so stock is 5WT gear oil? ...or is it specifically fork oil? and how does fork oil compare to gear oil? or can you buy heavier weight fork oil?
Just after reading through the VERY informative posts...the general concensus on posted averages has been between 40 to 90WT? Also seems confusing that stock weight is 5WT but most that reported changing to 30WT noticed no difference? So how does the stock fluid compare to gear oil?
Seems like a HUGE jump to me...???
I'm entering the phase of "suspension curiosity" so this is interesting and completely foreign material. I will point out that I have never had the opportunity to ride a tuned suspension, so if this is a "You'll know it when you feel it" type change, I could appreciate that aspect.
BTW, if it makes a difference, I'm 5'10" 205 dressed out on a stock K8 suspension (other than front being lowered 1.5" - plan to raise the back 1")
I ran 40wt non detergent in the OEM damper for over a year and was very satisfied. I then purchased a high end damper unit (Matris), top mount with 18 adjustment clicks and often while riding, adjust it for conditions. I believe it is an intergal part of an overall upgraded suspension.
Having said that, if you don't go to the track or twisties and are not an agressive rider, the $300-$500 cost may be impractical. Raydog
Having said that, if you don't go to the track or twisties and are not an agressive rider, the $300-$500 cost may be impractical. Raydog
Munchie
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Ahhh...I should have mentioned that I used to be a very aggresive rider until a high-side claimed my 01' silver/blue + injuries.
Now with my K8, I just cannot get this thing to move the way I could ride my 01'. I plan to begin track riding (more for the instruction) this coming season....although I haven't exactly figured out why I can't get this bike to move how I want, I've taken interest in the suspension as a potential target. I've considered an aftermarket damper but as you mention, $300-$500 is an expensive dice roll for me and I don't want to have unrealistic expectations.
I had a falling out with the original owner of the 01' (a "friend" that assured me the bike "needed nothing" - long story) so I did not have an avenue to inquire as to any suspension mods/setup changes.
Now with my K8, I just cannot get this thing to move the way I could ride my 01'. I plan to begin track riding (more for the instruction) this coming season....although I haven't exactly figured out why I can't get this bike to move how I want, I've taken interest in the suspension as a potential target. I've considered an aftermarket damper but as you mention, $300-$500 is an expensive dice roll for me and I don't want to have unrealistic expectations.
I had a falling out with the original owner of the 01' (a "friend" that assured me the bike "needed nothing" - long story) so I did not have an avenue to inquire as to any suspension mods/setup changes.
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With these modifications to your bikes geometry I'd say the investment into a high end adjustable damper would be a wise investment.
You have now shortened the trail to the point your ride may become unstable at speed? It will also want to fall over when you tip into a corner, especially if you are on the brakes.
You have created other issues but the most important is stability!
Munchie
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Tuf, it is hard to disagree with a persons choices without sometimes offending that person. I would say you have mastered this delicate ability...constructive critisism at its best
I appreciate your experience, enjoy reading your posts and value your opinion...
From the tone I take from your response (although I appreciate that tone), I would say you probably disagree with my changes? To a point, I do as well. I had an excellent riding buddy that hung up his gloves over my high side. I was following him when I went down and even though he wont admit it, I think he felt responsible for my get off. He had several good friends wipe out trying to run with him over the years, and I was the last.
Like yourself, he was also a "student" of the ride and always said that a team of the best engineers these companies could muster had designed our suspension geometry the way they did for a reason. He disagreed with my changes as well.
I attempted to lower the front to help with getting over and get the bike set into the turn earlier? Thinking maybe the shorter wheelbase might help? For a lack of a better way to describe it. Trying to find something to get this bike where my Gen1 was - but guessing since I don't know what that might have been...
Would you feel it's best to put the bike back to stock ride height? Steering damper? Suspension tune? My setup goal is strickly for cornering. Other recommendations are appreciated...
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You won't go wrong with Tuf's advice. I would like to make the point, however, that a dialed in suspension (including whatever internal mods are necessary) is an incredibly important prerequisite if you plan to explore both you and your motorcycle's limits. Good luck to you in your quest and remember....time invested in skill acquisition and money invested in motorcycle improvement can be a wonderful combination if you take this sport that seriously. Doyle
Munchie
Registered
Thanks Doyle...I appreciate your thoughts as well. Nice shot for your Avatar...
Would you guys think the stock setup has enough adjustment for my specs? Or recommend a springrate change as I've found so much about in my recent reading. Also, do yall feel the stock steering damper is worth upgrading/replacing?
BTW...I don't think it can be considered thread jacking once the original post hits a certain age!
Tuf, it is hard to disagree with a persons choices without sometimes offending that person. I would say you have mastered this delicate ability...constructive critisism at its best
From the tone I take from your response (although I appreciate that tone), I would say you probably disagree with my changes? To a point, I do as well. I had an excellent riding buddy that hung up his gloves over my high side. I was following him when I went down and even though he wont admit it, I think he felt responsible for my get off. He had several good friends wipe out trying to run with him over the years, and I was the last.
Like yourself, he was also a "student" of the ride and always said that a team of the best engineers these companies could muster had designed our suspension geometry the way they did for a reason. He disagreed with my changes as well.
I attempted to lower the front to help with getting over and get the bike set into the turn earlier? Thinking maybe the shorter wheelbase might help? For a lack of a better way to describe it. Trying to find something to get this bike where my Gen1 was - but guessing since I don't know what that might have been...
Would you feel it's best to put the bike back to stock ride height? Steering damper? Suspension tune? My setup goal is strickly for cornering. Other recommendations are appreciated...
When making suspension changes, you should keep in mind anything and everything you change has an effect on your bikes performance. A change, no matter how small will either improve or hinder the way your bike performs. By lowering the front and raising the rear that much I'm afraid you'll make the beast very difficult to ride agressively!
If you are interested in learning more about how your suspension functions and what effect each adjustment has on performance, Andrew Trevitt has a great book out "Sportbike Suspension Tuning". Well worth the $25!
Thanks Doyle...I appreciate your thoughts as well. Nice shot for your Avatar...
Would you guys think the stock setup has enough adjustment for my specs? Or recommend a springrate change as I've found so much about in my recent reading. Also, do yall feel the stock steering damper is worth upgrading/replacing?
BTW...I don't think it can be considered thread jacking once the original post hits a certain age!
Your stock suspension will handle anything you can throw at it. Until you get fast enough that you are spanking everyone in the intermediate group, your stock suspension will function just fine. If your forks aren't bottoming out, it's fine. Get your trackside suspension vendor to set your suspension up with a baseline and ride the wheels off that puppy.
At this point your money will be better spent on instruction. Sign up for a track school. You'll learn more in one day at school than you will learn all summer on your own.
As far as the steering damper upgrade with heavier oil, I'm not a real fan of 80/90w although many will argue that point. I'd leave the stock steering damper as is. Your busa is a gentle giant. As long as you don't mess with the geometry to much you should have no problem with head shake. Best thing to prevent a tank slapper is to stay off the rear brake at the track.
And yes, you'll be wise to put your suspension back to stock height before attending your first track day.
Munchie
Registered
Sorry for the late reply Tuf, just wanted to say thanks for the advice
and my copy of Trevitts book is on the way. Trackday event is on this list for early spring...looking for locations/options soon soon! hopefully...
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