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^Those are nice. I got mine from a local suspension guy for a few dollars.

There is really nothing special about the shim except that it fits. It seems most are going for about 5mm thickness from a single or a stack of washers. My K6 750 takes a 20mm ID washer.

I'm sure something appropriate can be sourced at a local Fastenal or other good hardware outlet.
 

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I took a micrometer to a local hardware store and picked up some thick washers to go under the upper mount and frame.

If you want to be fancy, you could cut a slot in the washer so they slide in and out without removing the upper mount completely. Like yosh's kit




Turn in is best addressed with lowering the front a couple mm's with the forks and triple. Raising the rear addresses corner exit issues more directly and will cause the front to drop significantly on brakes due to weight transfer and resetting the "bottom" of suspension travel back to front. However, this is with hard braking that you might not experience on the streets.

For a street bike, I would pull the forks up through the triple a couple mm;s and see if that gets what you want, first.
 

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Raising both ends has been a standard mod on my K6 and similar year bikes. The point is that it raises the center of gravity and makes for quicker transitions.

I flushed my forks which raised the front till it was flush (stock is 5mm above the triple) and the 5mm shim on the shock brought the rear up about 15mm as I recall.

The net result is higher bike with more nose down attitude to reduce trail and quicken turn in.
 

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So everything said above is absolutely correct. And if you want a sweet handling bike you can haul ass on the track follow what was offered above. :wink

However, my advice to you wasn't necessarily incorrect given your stated goal. And in my humble opinion will get you what you want with the least drama.

The reason I believe this to be true is that a perfectly set up bike for the track is not necessarily what is needed for the streets. What do I mean by that? Well, on the track, you are potentially much harder on the brake and gas and you put the bike through the extremes of suspension travel. On the streets, you might use 1/3 or 1/2 or 2/3 of that travel depending how hard you ride and how much you risk.

Since the track season has ended up here I have dedicated time to try to understand the geometry questions about this bike, and I think I've finally wrapped my head around it. At least in a general sense...
The following is my understanding of why the changes are being made in one particular way.

Suzuki has set up this bike so that 1) it is stable mid corner and 2) has plenty of traction in the rear on exit. In doing so, once the pace picks up riders notice the slow turn in usually first. Then if they venture on the track and get on the gas sooner and harder, they find the bike running wide on exit.

For the trackday heroes and more importantly the racers, this running wide on exit is unacceptable. By using different riding techniques, turn in can be sped up by trail braking into the corner, but running wide can only be fixed by easing out of the throttle. That kills exit speed and lap times. So, the first thing they fix is the swingarm angle and rear squat. This is why everyone raises the rear. Not so much to speed up turn in but to cure the running wide on corner exit.

The next thing people do is what confused me for the longest time. Why would you go to the trouble of raising the rear then take away that improved turn in by raising the front as well... However, ALL the fast gsxr's on track are raised front and rear.

Was it that the rear height increase took too much trail away from the front making the bike too unstable? or was it a center of gravity thing? or was it a weight transfer thing? I couldn't believe that raising the rear ITSELF caused the front of the bike to lose that much trail that it became unstable when the bike turned in slowly to begin with. It just did not compute.

UNTIL! I realized what they were fixing by raising the front was instability caused at a particular point in time! that was on the brakes <HARD>. If you think about it, without raising the front, on the brakes hard will cause the front to compress. With the rear ride height increased but the front ride height the same, more and more weight is transferred to the front and the front dives harder and faster reaching the bottom of travel easier. Once you reach the bottom of travel, the rear wheel starts to lift and maximum braking is reached sooner. I have noticed that since raising the rear, it is more difficult holding the bike steady at maximum braking. Never did it occur to me this was a geometry thing. I thought it was simply me being chicken.

What raising the front through the forks does is limit how much the front dives on hard brakes (suspension bottom is raised) and keeps a little more weight toward the rear allowing more stable and harder braking. This is what I was missing. This is why raising the front produced a faster bike! It was a eureka! moment.

So....
what does this have to do with a street bike? Are you on the gas hard enough coming out of a corner that you squat the rear causing you to run out of road? Are you braking hard enough that you compress the front to the point your rear wheel is becoming unstable? if not, I propose that fixing the swingarm angle with a rear ride height increase is unnecessary and to improve your turn in you could either drop the front through the forks a little or even better take some preload out of the front and run a little higher sag (this won't change the bottom of suspension travel like moving the forks will).

Hope some of this makes sense. But experiment and keep an open mind.

The faster you ride, the more you feel the perceived limitations of the bike set up then adjust accordingly.
 

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So everything said above is absolutely correct. And if you want a sweet handling bike you can haul ass on the track follow what was offered above. :wink

However, my advice to you wasn't necessarily incorrect given your stated goal. And in my humble opinion will get you what you want with the least drama.

The reason I believe this to be true is that a perfectly set up bike for the track is not necessarily what is needed for the streets. What do I mean by that? Well, on the track, you are potentially much harder on the brake and gas and you put the bike through the extremes of suspension travel. On the streets, you might use 1/3 or 1/2 or 2/3 of that travel depending how hard you ride and how much you risk.

Since the track season has ended up here I have dedicated time to try to understand the geometry questions about this bike, and I think I've finally wrapped my head around it. At least in a general sense...
The following is my understanding of why the changes are being made in one particular way.

Suzuki has set up this bike so that 1) it is stable mid corner and 2) has plenty of traction in the rear on exit. In doing so, once the pace picks up riders notice the slow turn in usually first. Then if they venture on the track and get on the gas sooner and harder, they find the bike running wide on exit.

For the trackday heroes and more importantly the racers, this running wide on exit is unacceptable. By using different riding techniques, turn in can be sped up by trail braking into the corner, but running wide can only be fixed by easing out of the throttle. That kills exit speed and lap times. So, the first thing they fix is the swingarm angle and rear squat. This is why everyone raises the rear. Not so much to speed up turn in but to cure the running wide on corner exit.

The next thing people do is what confused me for the longest time. Why would you go to the trouble of raising the rear then take away that improved turn in by raising the front as well... However, ALL the fast gsxr's on track are raised front and rear.

Was it that the rear height increase took too much trail away from the front making the bike too unstable? or was it a center of gravity thing? or was it a weight transfer thing? I couldn't believe that raising the rear ITSELF caused the front of the bike to lose that much trail that it became unstable when the bike turned in slowly to begin with. It just did not compute.

UNTIL! I realized what they were fixing by raising the front was instability caused at a particular point in time! that was on the brakes <HARD>. If you think about it, without raising the front, on the brakes hard will cause the front to compress. With the rear ride height increased but the front ride height the same, more and more weight is transferred to the front and the front dives harder and faster reaching the bottom of travel easier. Once you reach the bottom of travel, the rear wheel starts to lift and maximum braking is reached sooner. I have noticed that since raising the rear, it is more difficult holding the bike steady at maximum braking. Never did it occur to me this was a geometry thing. I thought it was simply me being chicken.

What raising the front through the forks does is limit how much the front dives on hard brakes (suspension bottom is raised) and keeps a little more weight toward the rear allowing more stable and harder braking. This is what I was missing. This is why raising the front produced a faster bike! It was a eureka! moment.

So....
what does this have to do with a street bike? Are you on the gas hard enough coming out of a corner that you squat the rear causing you to run out of road? Are you braking hard enough that you compress the front to the point your rear wheel is becoming unstable? if not, I propose that fixing the swingarm angle with a rear ride height increase is unnecessary and to improve your turn in you could either drop the front through the forks a little or even better take some preload out of the front and run a little higher sag (this won't change the bottom of suspension travel like moving the forks will).

Hope some of this makes sense. But experiment and keep an open mind.

The faster you ride, the more you feel the perceived limitations of the bike set up then adjust accordingly.
Great Write up JCW, AND everyone else also!

I totally agree with everything that's been said, and JCW, you had me until some of this:

" So....
what does this have to do with a street bike? Are you on the gas hard enough coming out of a corner that you squat the rear causing you to run out of road?

For me, usually not- country road spirited rides


Are you braking hard enough that you compress the front to the point your rear wheel is becoming unstable?

YES, but I also attribute it to the fact of it happening when I downshift to the lower gears as I enter a corner, and let out the clutch a little quick when I'm already braking hard, and it will drift slightly outside as I turn in.

if not, I propose that fixing the swingarm angle with a rear ride height increase is unnecessary and to improve your turn in you could either drop the front through the forks a little or even better take some preload out of the front and run a little higher sag (this won't change the bottom of suspension travel like moving the forks will).

Here's where I don't understand the last part. How is sliding up thru the triples changing the bottom of the suspension?
By adjustments, I thought taking out some preload was actually/physically get to the bottom of your travel a bit quicker. How is taking the same preload and sliding them up some changing that?
We both know you know more than I ever did about this. I'm simply asking so that I can undertand my bike and how it handles a bit better.
When I rarely go nearly top speed, it does not get any headshake or become unstable at all.
TIA

Hope some of this makes sense. But experiment and keep an open mind.

The faster you ride, the more you feel the perceived limitations of the bike set up then adjust accordingly."

With my forks pushed up thru the triples barely enough to get my clip on on top ot the triple (I have a thread on that), this did get it to turn in nicely, and I've been liking the way it has been handling.

I'm still thinking of trying a few shims in the rear as well!
 

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Give me a sec to figure the best way to explain it.
The words to describe the geometry changes don't come naturally to me yet, so let me gather my thoughts.
 

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So when I say changing the bottom of the front suspension, I mean a change in the height of the front of the chassis and angle of the chassis to the ground.

Obviously your "bottom out" on the forks can't change. But, depending on how high or low your triples clamp on the forks, how high the nose of your bike will change and the angle of the chassis to the ground will change. This is what I meant by changing the bottom of the suspension. When you compress the front end, the chassis rotates forward and because you are clamped farther down on the tubes, your front end will be lower, your rake with be less and your trail will be less.

Contrast that to increasing your sag number in front. Let the front "sag" lower. Yes, the chassis at rest will have less rake, less trail. But, compress the fork fully and your "bottom" will not change! You retain a little more stability on hard brakes.



Am I making sense?


In fact, one of the tricks to getting the gsxr tuned in perfectly on track is AFTER you 1) raise the rear 2) raise the front, you run higher than normal front sag numbers so you REGAIN some of that chassis angle to quicken the steering. BUT, you maintain the higher bottom out to prevent instability during hard braking and full compression.

It's hard to explain, and maybe even harder to visualize...
 

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YES, but I also attribute it to the fact of it happening when I downshift to the lower gears as I enter a corner, and let out the clutch a little quick when I'm already braking hard, and it will drift slightly outside as I turn in.

With my forks pushed up thru the triples barely enough to get my clip on on top ot the triple (I have a thread on that), this did get it to turn in nicely, and I've been liking the way it has been handling.

I'm still thinking of trying a few shims in the rear as well!
So, yeah, braking and downshifting will loosen the rear end and make the bike want to come around. That is different though than just full brake application to the point of lifting the rear.
How much different, I don't know as I don't do either with enough confidence to say.


Yes, I remember reading about your clip on position above the triples.
If the instability when you brake does not bother you (remember the most severe geometry change will be when the front is fully compressed) then you are fine. This kinda speaks again to how street riding and track riding differ. I would imagine if you practiced some really hard braking maneuvers, you would find some instability there you normally would not encounter even during spirited country road rides...
 

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Discussion Starter #17
Well after reading all this I may just leave it and change myself and see if that works but good explanations forsure I understand most of what your saying thanks
 

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That is not a bad plan.

If you don't know where the bike is set now, find out and write the settings down so you know what you changed and what effect it had. And it makes it easier to go back if you don't like it. I would be sure that the settings are somewhat near the factory recommended base settings. They are in your owners and service manual.

I should have mentioned earlier that tires can make a huge difference how the bike turns in and handles. If you have old, worn or squared off tires, you will be chasing your tail trying to make it handle well.
 

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That is not a bad plan.

If you don't know where the bike is set now, find out and write the settings down so you know what you changed and what effect it had. And it makes it easier to go back if you don't like it. I would be sure that the settings are somewhat near the factory recommended base settings. They are in your owners and service manual.

I should have mentioned earlier that tires can make a huge difference how the bike turns in and handles. If you have old, worn or squared off tires, you will be chasing your tail trying to make it handle well.
Also, if you could find a good suspension person to set the bike up per your weight it would help more than anything I think.
 
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