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fork oil or springs??


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not sure if I need srings or just change the fork oil, I am getting a bounce in the front end between 30 and 35, took the wheel off and re-ballanced, it was spot on, so thats not it, put a peice of card board in a clamp and set it allmost to the tire and spun the wheel, not out of round.... it is an `01 so springs are probably shot, just reaching for Ideas..

 

Thanks

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A bounce happening at such a specific and relatively low speed doesn't really sound like a spring problem. More like a balance problem, although one would expect it to get worse rather than go away at higher speeds (I'm assuming it foes away since you mentioned 30 to 35). If the springs were sacked out, you would expect the bike to ride a bit lower and maybe ground out sooner on turns or bottom out on bumps. We'll have to see what the forum experts have to say I guess.

 

Andy

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I should also have mentioned that if I hit the front brakes the bounce will go away and when I stop hard with the front brake the bike will go down pretty far and not really come all the way back up untill I give it gas..

 

 

 

A bounce happening at such a specific and relatively low speed doesn't really sound like a spring problem. More like a balance problem, although one would expect it to get worse rather than go away at higher speeds (I'm assuming it foes away since you mentioned 30 to 35). If the springs were sacked out, you would expect the bike to ride a bit lower and maybe ground out sooner on turns or bottom out on bumps. We'll have to see what the forum experts have to say I guess.

 

Andy

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I should also have mentioned that if I hit the front brakes the bounce will go away and when I stop hard with the front brake the bike will go down pretty far and not really come all the way back up untill I give it gas..

 

Dang Doodle! I told you to lay off the snacks!:rotf:

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Kreg,

 

What you describe is a classic (compression/rebound) dampening issue. In other words your oil has turned the consistency of water and is shot. It is also a 7.5 wt which is very thin.....the same weight that a sport bike with cartridge forks requires. It needs at least a 10wt. And I will suggest that the bottom of your forks are filled with a black sludge?

 

But when you talk about the front end diving a bunch, your issue is that the springs have lost all of their sag....yeah they are shot as well. The oem spring rate is .90kg/mm and what these bikes need is a spring rate of 1.2kg/mm. And while you have the forks out to change the fluid, you should go ahead and replace the springs.

 

The most convenient thing to do would be to use Progressive brand springs (which are a multiple spring rate) but most experts say you really need a constant rate 1.2 kg/mm spring that you can get from Race Tech, Sonic Springs (which I reccommend) and several other suppliers.

 

But this is not an easy task which will take most of a day to complete. You have to pull the fairing off and suspend it in order to get the forks out to drain, etc.

 

Hope this helps,

 

Rick

 

I have a set of springs (and cartridge emulators) to install on a friend's RSV later this year, so maybe I'll go ahead and work up a detailed set of instructions?

 

 

 

 

 

 

not sure if I need srings or just change the fork oil, I am getting a bounce in the front end between 30 and 35, took the wheel off and re-ballanced, it was spot on, so thats not it, put a peice of card board in a clamp and set it allmost to the tire and spun the wheel, not out of round.... it is an `01 so springs are probably shot, just reaching for Ideas..

 

Thanks

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Thanks Rick, that helped alot.. I kinda figured that after 10+ years that they are shot, but knowing what a job it is going to be, thought I would ask. gonna be a Dec. job. for sure. Thanks again.

 

 

 

 

Kreg,

 

What you describe is a classic (compression/rebound) dampening issue. In other words your oil has turned the consistency of water and is shot. It is also a 7.5 wt which is very thin.....the same weight that a sport bike with cartridge forks requires. It needs at least a 10wt. And I will suggest that the bottom of your forks are filled with a black sludge?

 

But when you talk about the front end diving a bunch, your issue is that the springs have lost all of their sag....yeah they are shot as well. The oem spring rate is .90kg/mm and what these bikes need is a spring rate of 1.2kg/mm. And while you have the forks out to change the fluid, you should go ahead and replace the springs.

 

The most convenient thing to do would be to use Progressive brand springs (which are a multiple spring rate) but most experts say you really need a constant rate 1.2 kg/mm spring that you can get from Race Tech, Sonic Springs (which I reccommend) and several other suppliers.

 

But this is not an easy task which will take most of a day to complete. You have to pull the fairing off and suspend it in order to get the forks out to drain, etc.

 

Hope this helps,

 

Rick

 

I have a set of springs (and cartridge emulators) to install on a friend's RSV later this year, so maybe I'll go ahead and work up a detailed set of instructions?

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For what it's worth, I replaced my front springs with Progressives this summer along with 10 wt fork oil and I'm VERY happy with the results. Mine is an '03 and it was diving a bit under breaking and "floating" after going across a good bump before the change. All is good now.

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Kreg,

 

What you describe is a classic (compression/rebound) dampening issue. In other words your oil has turned the consistency of water and is shot. It is also a 7.5 wt which is very thin.....the same weight that a sport bike with cartridge forks requires. It needs at least a 10wt. And I will suggest that the bottom of your forks are filled with a black sludge?

 

But when you talk about the front end diving a bunch, your issue is that the springs have lost all of their sag....yeah they are shot as well. The oem spring rate is .90kg/mm and what these bikes need is a spring rate of 1.2kg/mm. And while you have the forks out to change the fluid, you should go ahead and replace the springs.

 

The most convenient thing to do would be to use Progressive brand springs (which are a multiple spring rate) but most experts say you really need a constant rate 1.2 kg/mm spring that you can get from Race Tech, Sonic Springs (which I reccommend) and several other suppliers.

 

But this is not an easy task which will take most of a day to complete. You have to pull the fairing off and suspend it in order to get the forks out to drain, etc.

 

Hope this helps,

 

Rick

 

I have a set of springs (and cartridge emulators) to install on a friend's RSV later this year, so maybe I'll go ahead and work up a detailed set of instructions?

 

Rick,

 

I am very interested at seeing this set of instructions. Will be upgrading the springs this winter as they are getting pretty weak (or maybe I am just gaining weight - Naaahh!).

 

RR

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I changed out my fork oil two months ago. I went to 15W oil (Honda brand) and did not notice significant change in damping as a result.

 

I considered replacing the springs at that time, but decided against it because the bike had only 22k miles on it, and I've been happy enough with the action of the forks as they came from the factory. Next time I do this I will install new springs, just 'cause.

 

I had a helluva time getting the fork caps back on. My 62 y/o hands aren't what they used to be, and I didn't have a helper. So... I ended up making a tool out of a chunk of wood. I chiseled out a space in the woodblock for the air housing on the cap such that I could apply strong pressure to the cap as I turned it clockwise, the air housing acting as a hold point for the block. I used the bike's lower bracket as a vise, since my puny little chinese vise wasn't up to the job. One critical step under these conditions was to index the cap threads with the forktube threads before starting. With the bike chassis in the way, there's only about 60 degrees of rotation available. Therefore, the threads have to engage almost immediately. The indexing obviously has to be done prior to mounting the forktube into the lower bracket, with spring out. Find where the threads first engage, then make a feltpen mark on both cap and tube to find the spot. Start at that aligned spot, push the cap down onto the spring, turn the cap carefully so as not to crossthread, and that's the job. Next time I do this I will burn a lot fewer calories.

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Thanks Rick, that helped alot.. I kinda figured that after 10+ years that they are shot, but knowing what a job it is going to be, thought I would ask. gonna be a Dec. job. for sure. Thanks again.

 

DECEMBER????? Heck I thought you were gonna learn all the "gotchas", pretty quick, so I could bring my bike out there and you could change the oil in it!!! :whistling:

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well, bring it Walt, and we can have them both tore up at the same time!! I just don`t want to mess up any riding weather should it take more then a day to do, but want to have it done before RockPort..

 

Kreg

 

 

DECEMBER????? Heck I thought you were gonna learn all the "gotchas", pretty quick, so I could bring my bike out there and you could change the oil in it!!! :whistling:
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LOL will do...may need to get Gumbo and his BIG hammer as well, gonna order the springs in a few weeks.. what all do I need to get????

 

Let me know when, I may just pester some of you for a bunk so we can change the oil in mine.

 

AND if past history is any indication I'll need Thor's hammer!!!:starz: :big-grin-emoticon:

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