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Discussion Starter · #1 ·
when I accelerate hard in first and second and sometimes as i change into third over bumps the front end will shake, my understanding is the when the power is applied the rear sqauts thus transferring the weight back and making the front light

From what iv learnt i have to increase rear preload my questions is i like the the SAG the way it is 38/35 how can i fix this with out changing it
 

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crashing aint so bad
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Sag isn't always the cure. Try setting for faster rebound ( softer rebound settings ) in the front forks. Also work on not holding onto the bars to tight. That is the primary cause of tank slappers. Holding onto the bars to tight is the quickest way to get a slapper that seems pre-mature.

The sag settings you have are a little on the SAGGY side. As a goal, you should shoot for about 30-35mm on the street, although it is still a matter of preference. 38mm is a bit on the spongy side and it increases your chance of bottoming out the forks, or shock.

If you were to change no settings at all on the bike, my bet is that you cold reduce the issue by simply relaxing your grip on the bars. You only need to hold on enough to keep from flying off. I try letting my but and feet on the pegs do most of the work keeping me on the machine. I try to hold onto the bars as if they were eggs. They really shouldn't be strangled.
 

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Discussion Starter · #4 ·
Thanks Luke
Its not quite tank slappers i think called frontend chatter, i have a hyperpro steering damper set on the softer setting

I will change the SAG to 36/32 im going for a ride today, is it ok to run 38/32 or do the front and rear be more even

I heard Dave Moss say you should set high speed comp to 1/3 out from full stiff and leave it for the track is this ok for the steet or do you want it softer
 

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Thanks Luke
Its not quite tank slappers i think called frontend chatter, i have a hyperpro steering damper set on the softer setting

I will change the SAG to 36/32 im going for a ride today, is it ok to run 38/32 or do the front and rear be more even

I heard Dave Moss say you should set high speed comp to 1/3 out from full stiff and leave it for the track is this ok for the steet or do you want it softer
My Post about setting sag - From this I found out most people run 35 front, 28 rear. And that the front and rear should not match. I wouldn't change your compression until you get the sag set first. Summary of that thread here in this post.

As mentioned, most of the time this happen just from holding onto the bars too tight. After reading Twist of the Wrist 2, and starting to incoporate some of the things I learned, mainly relaxing on my grip some (using my legs to hold on, trying to keep my arms bent so I can't hold on too tight) my wobbles have stopped.
 

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Thanks Luke
Its not quite tank slappers i think called frontend chatter, i have a hyperpro steering damper set on the softer setting

I will change the SAG to 36/32 im going for a ride today, is it ok to run 38/32 or do the front and rear be more even

I heard Dave Moss say you should set high speed comp to 1/3 out from full stiff and leave it for the track is this ok for the steet or do you want it softer
The sag settings do not need to be even. And they are only intended as starting points.

The high speed compression damping is subjective, and is not the cause of the symptoms you describe.
 

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If you were to change no settings at all on the bike, my bet is that you cold reduce the issue by simply relaxing your grip on the bars. You only need to hold on enough to keep from flying off. I try letting my but and feet on the pegs do most of the work keeping me on the machine. I try to hold onto the bars as if they were eggs. They really shouldn't be strangled.
How far back on the seat do you sit when your spirited riding? I can barely flatfoot when I'm all the way up front and I have to lean forward a lot just to reach the bars when I'm sitting back
 

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crashing aint so bad
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I don't think where you sit will make a huge difference in the speed wobbles. The wobbles are a needed and expected result of a rigid grip on the bars. The front end will do that regardless of the amount of weight transfer. Once there is enough rearward weight transfer from acceleration and a rigid grip on the bars is acquired, tank slappers are soon to ensue.

As for sag, no they do not need to be equal. The numbers provided are just a window for an ideal goal. The easiest way to tell if you need more or less sag on the front is to use a zip tie around the fork leg. When the fork compresses it will push the zip tie down. Checking it after a SPIRITED ride will show how much fork travel you are using. A good goal is to set sag so that you use most all of the travel. So you should be looking for the zip tie to stop with between 1/4" & 1/2" left of possible travel. If there is less than 1/4" you need to add pre load and if you have more than 1/2" you need to reduce pre load. The rear is a little more tricky and requires you to go more with feedback rather than hard numbers. I try to err to the stiff side for better turn in. The sacrifice is a little less rear grip. Being in the general sag window is pretty good if the rear spring is good for your weight. In either case sag should be set properly and for best feel before any compression and rebound damping knobs are twisted.

As for running track compression and rebound settings on the street, there is no real difference. The settings meant for the street are more for comfort and a compliant predictable machine. The track settings are more for best handling and not focused on rider comfort. Track settings on the street are just fine, the only difference is the ride will not be as plush or cushy. I would shy away from running street settings at the track however. Especially if you are a faster street rider. There always seems to be a false sense of security with a plush ride. There is less feedback so traction feel is diminished with street settings.

Compression be it high or low speed is more of a comfort thing. It is the least important setting and has only a couple of side effects if it is wrong. To hard and the bike will have chatter and turn in will not be as good. The up side is that to stiff a compression setting will yield better braking results. To soft a compression setting will make the bike TOO TWITCHY on turn in and braking will be diminished. The up side to too soft a compression setting is that chatter is less likely. This is for the front.

The rear is a little different but still not as important as a good rebound setting. Basically too soft and the bike can run wide out of turns and traction will do a slip and grab thing instead of just sliding. Too hard and rear tire traction will just plain suck and turn in may be too twitchy.

Rebound should be thought of as fast or slow instead of hard or soft like compression. Too fast a rebound allows the forks or shock to de-compress too quickly, and too slow will not allow the forks or shock to de-compress fast enough. The ideal setting is one that is as fast as can be with good bike control. The bike should not wallow and pogo when bumps are hit mid turn and the bike should have good attitude and inspire confidence any other time. Too fast or too slow will effect both of those goals. Slower rebound increases confidence because of reduced feedback through the bike, but also make the bike more likely to loose traction. Faster rebound increases feedback which can reduce rider confidence and will not have as much bike attitude control. Again this goes for both front and rear.

I try to fix the problems first before blaming things on the machine. We as riders are problems for the machine. So we usually need to look at ourselves first before we try and FIX THE BIKE. Good riding habits will reduce handling issues and make it much easier to dial the bike in when a change is truly needed.
 

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Discussion Starter · #9 · (Edited)
ok got back from my ride today the bike does pogo a bit and the rear is a bit jarring over bumps but mid corner is ok tomorrow i will get the zip ties out and sort out the SAG and rebound

as for the frontend chatter it must be me i though i was loose on the bars but obviously not might take some valium before i go out
 

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download Twist of the Wrist II from a torrent.
it will show you why you are getting front end shake over bumps and acceleration...hint....it's all the rider's fault. they'll show you how to eliminate or lessen these effects.

and just so you know, the rear end doesn't squat under accelertion. that's a common misconception about motorcycle suspension that most rider believe.
but the rear actually raises and stiffens. which is why it's so important to have good throttle control when getting on the power out of corners. because is takes away from the shock being able to follow the road surface and the tire has to absorb it and apply the power to the ground. resulting in less grip.
which is also why it's important to stay loose and not hang on with your arms.

everything is connected. as you'll see in the video.
 

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download Twist of the Wrist II from a torrent.
it will show you why you are getting front end shake over bumps and acceleration...hint....it's all the rider's fault. they'll show you how to eliminate or lessen these effects.

and just so you know, the rear end doesn't squat under accelertion. that's a common misconception about motorcycle suspension that most rider believe.
but the rear actually raises and stiffens. which is why it's so important to have good throttle control when getting on the power out of corners. because is takes away from the shock being able to follow the road surface and the tire has to absorb it and apply the power to the ground. resulting in less grip.
which is also why it's important to stay loose and not hang on with your arms.

everything is connected. as you'll see in the video.
Please don't link copyrighted material. The Codes are members of the R1 Forum, and frequently read several motorcycle Forums.
 

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Please don't link copyrighted material. The Codes are members of the R1 Forum, and frequently read several motorcycle Forums.
ok but it's not like they don't know it's already on the net for download.
linking to a torrent of it doesn't mean the forum or I or you are responsible for putting it there.
 

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ok but it's not like they don't know it's already on the net for download.
linking to a torrent of it doesn't mean the forum or I or you are responsible for putting it there.
I do understand your point fully, as this has been addressed several times. If you feel I am out of line with this request, please feel free to contact the Forum Admin (SpidermanSS) and discuss it with him. I just don't want to open the Forum to any potential liability. I'm sorry for the inconvenience.
 

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Discussion Starter · #14 ·
I went on another ride today and made sure i was loose on the bars and its way better you dont even need to hold on once the bikes set in the turn although i feel im still puting alot of weight on the bars during hard braking i grip with my knees how are you suppose to do it

Also rode with the zip ties they were an inch from the bottem with 38mm SAG so might and just a bit of preload
 

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I went on another ride today and made sure i was loose on the bars and its way better you dont even need to hold on once the bikes set in the turn although i feel im still puting alot of weight on the bars during hard braking i grip with my knees how are you suppose to do it

Also rode with the zip ties they were an inch from the bottem with 38mm SAG so might and just a bit of preload
an inch is getting close if you were just riding normal without super hard braking etc.
I would add some preload myself.

braking is another thing. it's almost impossible to not put weight on the bars. and it's ok if you are straight up.
with good throttle control you don't need any steering input once in a corner.
hanging on with your arms and stiffening (or tensing) up on the bars is what you want to avoid. that's the most common survival reaction for motorcyclists (aka SR#2, tightening on the bars) also don't tense up your back. use your legs to help absorb bumps.
 

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I do understand your point fully, as this has been addressed several times. If you feel I am out of line with this request, please feel free to contact the Forum Admin (SpidermanSS) and discuss it with him. I just don't want to open the Forum to any potential liability. I'm sorry for the inconvenience.
naa man I'm not arguing. and I repsect the fact you guys don't want us to do that.
in fact I would highly recommend this video to anyone to buy.
 

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I would as Blue suggested add preload. Set it for the 35 mm area. With and inch left if you pull a wheelie or hit a pothole or large bump it will take care of the rest. that is why I said SPIRITED ride. One that is really up to pace vs. your typical cruise. Hence why it is better to set this kind of stuff at the track and then leave it.
 
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