rear preload adjustment
- Thread starter Liltroy
- Start date
https://www.hayabusa.org/forum/maintenance-do-yourself/89876-jinkster-attacks-suspension.html
Here is what you looking for. In the "Do it yourself" section
Here is what you looking for. In the "Do it yourself" section
Thanks for the link. Theres alot of good info there BUT i dont really like the idea of beating on my spanner nut to adjust it. I'd much rather use the right tool for the job and I've found an adjustable spanner wrench set at Harbor frieght for $25 since I posted this. I do have another question though.......I know the bike is adjusted from the factory for a 165lb rider....so what are the "factory settings" for a 240lb rider?
There are no "factory settings". The important measurement for preload is the rear sag setting. For street use, you should aim for 1 1/8" to 1 1/4" of sag; if you're heading for the track, shoot for 1".
mike1180
Banned
I tried the spanner wrench and it is hard to use when the shock is still on the bike.
You can get a brass drift and that will not even mark the adjusting rings - worked way better for me.
Ok, I'll have to try out that write-up then. When I had my Katana, there was a writeup in chart form for adjusting tire pressure, preload, and damping per bodyweight. I just thought that someone may have done something similiar for the busa here.
I didnt have any problem using the spanner wrench that I bought....just had my buddy lift up to unload the rear suspension a bit and cranked it down a few turns....took about 5 seconds. I guess it depends on the wrench design maybe???
mike1180
Banned
Here are my setings if you can use them.
I am 5ft 11 in and 220 lbs.
I ride on the road all the time, no track, and medium hard, not really hard.
I use Pilot Powers and use the 10% rule: (Hot temp tire pressure is 10% more than cold temp tire pressure),
so Fronts: cold = 36 pounds, hot = 40 pounds.
Rear: cold = 37 pounds, hot = 41 pounds
Here are my suspension settings:
(Might give you a start point, but you should play with them for your own best feel.)
.
I am 5ft 11 in and 220 lbs.
I ride on the road all the time, no track, and medium hard, not really hard.
I use Pilot Powers and use the 10% rule: (Hot temp tire pressure is 10% more than cold temp tire pressure),
so Fronts: cold = 36 pounds, hot = 40 pounds.
Rear: cold = 37 pounds, hot = 41 pounds
Here are my suspension settings:
(Might give you a start point, but you should play with them for your own best feel.)
.
mike1180
Banned
I did not save those numbers. The method of obtaining them is described in the thread linked above, and his numbers will be different from mine.
I told him “(Might give you a start point, but you should play with them for your own best feel.)” so I am assuming he will set up his suspension to suit him.
Liltroy, he is right you have to set yours up for your weight and your own bikes unique “stiction” characteristics.
The sheet that I included for you was my working sheet, for your amusement, and as an example only.
We can argue semantics, but when my preload is all the way in the result is my ride is stiffer than when it is all the way out.
I will be the first to admit this setup procedure is not an exact science, or there would be a chart for every weight and riding type, and a person could just dial it in to those numbers.
As with most things that we can do to these bikes, play with it until you get something you like, and then that will be your unique best option.
This, as all things I post, is JMO.
I told him “(Might give you a start point, but you should play with them for your own best feel.)” so I am assuming he will set up his suspension to suit him.
Liltroy, he is right you have to set yours up for your weight and your own bikes unique “stiction” characteristics.
The sheet that I included for you was my working sheet, for your amusement, and as an example only.
We can argue semantics, but when my preload is all the way in the result is my ride is stiffer than when it is all the way out.
I will be the first to admit this setup procedure is not an exact science, or there would be a chart for every weight and riding type, and a person could just dial it in to those numbers.
As with most things that we can do to these bikes, play with it until you get something you like, and then that will be your unique best option.
This, as all things I post, is JMO.
mike1180
Banned
Here are some other peoples recommended settings:
Sport Bike Motorcycle Suspension Settings - Sportbike Review - Sport Rider
Suzuki Hayabusa GSX1300R Performance Statistics Page 2
and another article about tuning it in:
Factory Pro: Producers of the EC997 Low Inertia Eddy Current Dynamometer Series and Quality MC performance products
then go to: Product Support technical Support
then go to: Motorcycle Tuning Tech
then go to: Suspension Tuning
Good luck!
Sport Bike Motorcycle Suspension Settings - Sportbike Review - Sport Rider
Suzuki Hayabusa GSX1300R Performance Statistics Page 2
and another article about tuning it in:
Factory Pro: Producers of the EC997 Low Inertia Eddy Current Dynamometer Series and Quality MC performance products
then go to: Product Support technical Support
then go to: Motorcycle Tuning Tech
then go to: Suspension Tuning
Good luck!
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Mike...You dont have to explain bro, I understand that it was a starting point and I really appreciate the help. As far as "stiffening things up" by adding preload...I have to agree. No, it doesnt change the actual "spring weight" but by having the spring already compressed more, it stiffens the ride considerably and also keeps it from sagging as much when going through the corners or just when I sit my 250lb ass on it,lol. Like I said, there was a setup by wieght chart on a katana forum I used to frequent that I used to set up my 06 katana 600 but unfortunatly...the answer for anything over 230lbs was simply Preload all the way up! LOL but it did improve my confidence when riding it through the twisties. when I bought this busa it was on all stock setting and felt like I was riding a friggen cruiser. The only thing I've done is to crank the preload up a few turns in the rear and already it feels much more stable(although a bit more harsh on rough roads as well). If the weather permits, I'll be putting all these setup articles that all you good folks have recommended to use this weekend and see if I cant get it where I want it. My future plans DO include some racetech springs both front and rear in the future, but I cant aford that immediately so I'll just have to deal with the stockers for now. Again, Thank for all the great links and hints guys.
mike1180
Banned
Cheers
Hey I recognize you now. You’re the one that said the suspension doesn’t need to be adjusted when you have a passenger, because the rear springs are linear…not?
And that the steering stabilizer has only 1 setting because the Suzuki engineers picked the “optimum oil weightâ€â€¦not?
The sag number is computed and the preloads adjusted to fit that, and the unless something changes (ie gain weight, change springs, etc.), it probably does not need to be adjusted again, so I discarded them. Again they will be different for him and for everyone else, so what is your point? He has already admitted he is heavier than me so…?
After that is set, I played with compression and rebound and did keep those settings, which I provided to him on the basis that I mentioned. Those are again individual preference for the rider and the bike.
I will stick to my opinion that my suspension feels stiffer, and firmer, and rougher, and harder etc. etc. when the preload is dialed in further. When it is dialed out it feels softer, mushier, smoother, etc.
That is a feeling. Feelings are the property of the individual, and unless you are me, I am not going to listen to any corrections you have to my individual feelings. Again that is semantics.
He got what I was talking about and I don’t know why you need to try and correct me instead of just helping the guy out.
I have set my bike up exactly the way I like it, and it FEELS good and that is all that matters. If you want to call that misguided, well I guess I'll have to wait until I am as enlightened as you are as to what is best for me.
Oh and I don't feel bad about it at all (OH OH a feeling again)
Hey guys...easy. I didnt mean to start a riot,lol. On the subject of preload stiffening things though, A mod that I picked up from a site for the katana was to remove the metal spacer tube from the front fork tubes and replace it with a longer piece of tube to compress or preload the springs a bit more(katana doesnt have front preload adjustment).....and yes, it does indeed stiffen it up. The guy that came up with it even had it dialed out to adding 1/2 inch for every 50 lbs of bodyweight over 160lbs or something like that. I'm not going to go into the physics of why it works but I'll only say, take a spring and try to compress it with your hands.....the more you compress it, the harder it gets to compress it that much further. Thats what makes it a spring.
Both linear and progressive springs are both going to react this way. The tighter they're compressed, the harder it gets to compress them more. The difference is that with the progressive spring, the first few coils or very easily compressed while the rest of the coils have a higher spring rate so as it is compressed, its going to be very easy to compress past the "soft coils" then its going to suddenly get harder to compress whereas wthe linear spring has the same spring rate all the way through so its going to gradually get harder to compress at a steady rate. Hope this makes since and helps alleviate any confussion and future argueing.
EDIT: Ok, after reading my own post, I felt it necessary to clarify something that may be misinterpreted. The spring is NOT actually getting stiffer(the spring rate is still going to be the same) but it is going to FEEL stiffer because it is already being loaded to a point....hence the term "pre-load"
Both linear and progressive springs are both going to react this way. The tighter they're compressed, the harder it gets to compress them more. The difference is that with the progressive spring, the first few coils or very easily compressed while the rest of the coils have a higher spring rate so as it is compressed, its going to be very easy to compress past the "soft coils" then its going to suddenly get harder to compress whereas wthe linear spring has the same spring rate all the way through so its going to gradually get harder to compress at a steady rate. Hope this makes since and helps alleviate any confussion and future argueing.EDIT: Ok, after reading my own post, I felt it necessary to clarify something that may be misinterpreted. The spring is NOT actually getting stiffer(the spring rate is still going to be the same) but it is going to FEEL stiffer because it is already being loaded to a point....hence the term "pre-load"
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When you adjust preload you are not compressing the spring further (you would have to add weight to the bike to do that). By adjusting the shock collar you are changing where the spring rests on the body of the shock.
Preload does not effect spring stiffness, PERIOD.
Cut and paste from;
Sport Rider Technicalities-Spring Rate and Preload
"When you tighten the adjusting collar on a shock or increase the preload length by tightening the adjuster on the fork, you are indeed increasing the initial force exerted by the springs. This decreases sag, making the bike ride higher. It does not, however, increase the spring rate."
Cut and paste from;
Suspension Tuning:* Preload
"It’s important to understand what you’re doing while cranking down on that adjuster. Increasing preload does not result in a stiffer spring. It only changes the amount of load it takes to begin to compress the spring. Spring stiffness is determined by the manufacturing process, and is usually expressed in lbs/in or kg/cm. As an example, a 100-lb/in. spring preloaded 2 inches will not compress further with any weight less than 200 pounds, but will compress 1 inch per 100 pounds above that. Normally, stock springs should work well enough unless you are very light or very heavy, or if you carry gear or ride two-up. If you find that you are near the limits of your preload adjustments to achieve proper static sag, you may need to consider changing your springs. Also, if your static sag is correct but free sag is less than recommended (5-10mm) or if the suspension is topping out, a heavier spring rate is indicated. Conversely, a lighter rated spring may be in order if free sag is more than desired."
cheers
ken
Preload does not effect spring stiffness, PERIOD.
Cut and paste from;
Sport Rider Technicalities-Spring Rate and Preload
"When you tighten the adjusting collar on a shock or increase the preload length by tightening the adjuster on the fork, you are indeed increasing the initial force exerted by the springs. This decreases sag, making the bike ride higher. It does not, however, increase the spring rate."
Cut and paste from;
Suspension Tuning:* Preload
"It’s important to understand what you’re doing while cranking down on that adjuster. Increasing preload does not result in a stiffer spring. It only changes the amount of load it takes to begin to compress the spring. Spring stiffness is determined by the manufacturing process, and is usually expressed in lbs/in or kg/cm. As an example, a 100-lb/in. spring preloaded 2 inches will not compress further with any weight less than 200 pounds, but will compress 1 inch per 100 pounds above that. Normally, stock springs should work well enough unless you are very light or very heavy, or if you carry gear or ride two-up. If you find that you are near the limits of your preload adjustments to achieve proper static sag, you may need to consider changing your springs. Also, if your static sag is correct but free sag is less than recommended (5-10mm) or if the suspension is topping out, a heavier spring rate is indicated. Conversely, a lighter rated spring may be in order if free sag is more than desired."
cheers
ken
thats what I was saying bro. The spring rate is constant. The ride only "feels" stiffer because the spring is being "squeezed" harder. its not actually making it more stiff.
Spring stiffness is determined by the manufacturing process, and is usually expressed in lbs/in or kg/cm. As an example, a 100-lb/in. spring preloaded 2 inches will not compress further with any weight less than 200 pounds, but will compress 1 inch per 100 pounds above that.
If you've adjusted the preload up and inch, than its going to feel like its stiffer because with the spring all the way down,if you hit a bump,and you weighed 200lbs, the spring would have given 2 inches....now with the preload adjusted an inch up, its only going to give an inch. The bikes not going to give and dip as much, thereby giving the illusion of a stiffer ride.
Spring stiffness is determined by the manufacturing process, and is usually expressed in lbs/in or kg/cm. As an example, a 100-lb/in. spring preloaded 2 inches will not compress further with any weight less than 200 pounds, but will compress 1 inch per 100 pounds above that.
If you've adjusted the preload up and inch, than its going to feel like its stiffer because with the spring all the way down,if you hit a bump,and you weighed 200lbs, the spring would have given 2 inches....now with the preload adjusted an inch up, its only going to give an inch. The bikes not going to give and dip as much, thereby giving the illusion of a stiffer ride.
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mike1180
Banned
Mike...You dont have to explain bro, I understand that it was a starting point and I really appreciate the help. As far as "stiffening things up" by adding preload...I have to agree. No, it doesnt change the actual "spring weight" but by having the spring already compressed more, it stiffens the ride considerably and also keeps it from sagging as much when going through the corners or just when I sit my 250lb ass on it,lol. Like I said, there was a setup by wieght chart on a katana forum I used to frequent that I used to set up my 06 katana 600 but unfortunatly...the answer for anything over 230lbs was simply Preload all the way up! LOL but it did improve my confidence when riding it through the twisties. when I bought this busa it was on all stock setting and felt like I was riding a friggen cruiser. The only thing I've done is to crank the preload up a few turns in the rear and already it feels much more stable(although a bit more harsh on rough roads as well). If the weather permits, I'll be putting all these setup articles that all you good folks have recommended to use this weekend and see if I cant get it where I want it. My future plans DO include some racetech springs both front and rear in the future, but I cant aford that immediately so I'll just have to deal with the stockers for now. Again, Thank for all the great links and hints guys.
Thanks!
All I am saying is that the thread linked at the top of this topic is how it should be done.
I don't think Tufbusa and I disagree on that.
I also gave you my settings, and 2 others (links in my previous post) so you can have some idea as to the thoughts of others on the topic. (one of those is Sport Rider, quoted by others here, and they have a "recommended settings" posted on their site, for what they think would be a good setup).
Anyway what I do is take all the advice and opinions, and then do what I think works and feels best for me.
Good luck brother!
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