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anybody know exactly how to polish the tubes? what polishing compound is being used? I may take a shot at trying to polish the tubes and valves while I have it apart, maybe dremmel the valve openings a bit? Anybody try doing some homemade polishing on their forks and care to give a quick "how to"? thanks
 

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well my parts came in today and the cbr1000rr springs are too short, looks like the ohlins specs were right.. :thumbd:

Here are the dimesions for the OEM 06 cbr1000rr forks from Honda:

length - 220mm
diameter - 40mm
weight - 245 grams

I havent pulled my springs out yet but based on Ohlins replacement specs I'm guessing the stock CBR954rr springs are 250mm...


Does anybody have length, diamater & weight measurements for the stock 954 springs?
 

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if you have a calliper, measure the thickness of the coil and multiply it by the number of coils in the spring. Do the same for the 954 spring to determine if they're close to the same fully compressed. That way you can just make some new spacers to make up for the difference and run these springs.
 

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if you have a calliper, measure the thickness of the coil and multiply it by the number of coils in the spring. Do the same for the 954 spring to determine if they're close to the same fully compressed. That way you can just make some new spacers to make up for the difference and run these springs.

Im not sure I follow the formula / calculations but the cbr1000rr springs are 4.9mm thick and there are 16 coils ....
 

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I made a spring compressor out of pvc and a clamp but havent had a chance to see if it works.. I found the design om another forum after googling "how to make a spring compressor".. looks pretty cool, maybe I can use it as a rocket launcher when I'm done with the forks. :patriot:
 

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It's simply 4.9 x 16 = 78.4mm fully compressed.

So, if the free length of the spring is 220mm take away 78.4 that leaves you with 141.6mm of travel before the spring would bottom out.
 

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It's simply 4.9 x 16 = 78.4mm fully compressed.

So, if the free length of the spring is 220mm take away 78.4 that leaves you with 141.6mm of travel before the spring would bottom out.
Ok I follow that, but how would I compensate with washers or a pvc spacer based on those numbers minus the stock numbers and what is the maximum "spacer" that can be used without seriously affecting fork performance? If the stock spring is 250mm & CBR1000 spring is 220mm then I'm already at a 30mm deficit and thats a pretty large gap..

I have some specs that I had written down when I did my initial suspension set-up when I got the bike (bought it new in the crate) and some additional tweaking done before a track day ( a few years later) which is the current settings, I dont know how the stiction got reduced for the second set-up since I didnt do any internal modifications (perhaps the forks just got broken in?), heck I still have the stock oil & seals in it so it's definitely way overdue for a change at 31,xxx miles:

Specs Initial - Current
stiction - 14mm - 10mm
free sag - 22.5mm - 19mm
rider sag - 39.5mm - 35mm
pre-load - 9 turns - 9.5 turns
compression - 2 turns - 1 turn
rebound - 2.5 turns - 2.5 turns

front wheel travel - 110mm
oil - SS8 (10w)
spring free length - 255.8
 

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You'll have to perform the same measuents of the stock spring to get it's fully compressed length as well. Chances are it's pretty close as a softer spring will have thinner coils but more turns.

Adding a spacer to the stiffer coil isn't as simple as just taking the difference between the two and cutting a spacer to make up for the difference. A stiffer spring won't compress as much and would therefore not have the same sag, it would sit much higher with the same weight on it.

You would have to make a bunch of calculations involving the kg/mm rate if each spring and how much they need to compress when installed to achieve the same setting.

You could try installing it without any spacer as long as it's not loose as the preload adjuster has about 25-30 mm of adjustment to it to start with.
 

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You'll have to perform the same measuents of the stock spring to get it's fully compressed length as well. Chances are it's pretty close as a softer spring will have thinner coils but more turns.

Adding a spacer to the stiffer coil isn't as simple as just taking the difference between the two and cutting a spacer to make up for the difference. A stiffer spring won't compress as much and would therefore not have the same sag, it would sit much higher with the same weight on it.

You would have to make a bunch of calculations involving the kg/mm rate if each spring and how much they need to compress when installed to achieve the same setting.

You could try installing it without any spacer as long as it's not loose as the preload adjuster has about 25-30 mm of adjustment to it to start with.
This is why I should've majored in Mechanical Engineering in college instead of Liberal Arts..LOL!

I guess it's time to pull out the stock spring and start doing some calculations.. my question would be how do we fill in that initial 30mm gap
in free length? If my adjusters only have about 25-30mm preload adjustment then wouldn't that be maxxed out on full settings just to reach zero preload to contact the spring before I even started to get into the positive numbers of compressing it or would the air and oil take up that gap or am I just not understanding the internal characteristics of how the fork operates? :idunno:
 

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No the stock springs are already under tension as assembled with zero preload adjustment. They are not in there loose as I'm guessing is your thought.

Once you get it apart you'll know what I'm talking about.
 

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Hi!

Great guide and all but I could use some help here.

Post #11 says: "..I held the opposite end of the damper with a 15mm wrench to keep it from rotating while I torqued the bolt."

I mus be stupid but I can´t figure where to put this 15mm wrench?
When I try to torque the damper bolt, the damper inside the tube is rotating.

When I did the other fork leg i guess i had some luck, cause I didn´t need to hold the damper then when I torqued it (it didn´t rotate for some reason).
 

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Discussion Starter #92
Hi!

Great guide and all but I could use some help here.

Post #11 says: "..I held the opposite end of the damper with a 15mm wrench to keep it from rotating while I torqued the bolt."

I mus be stupid but I can´t figure where to put this 15mm wrench?
When I try to torque the damper bolt, the damper inside the tube is rotating.

When I did the other fork leg i guess i had some luck, cause I didn´t need to hold the damper then when I torqued it (it didn´t rotate for some reason).
Sorry for the confusion here. If the damper is turning while you are trying to tighten the bolt in the bottom of fork try applying downward pressure on the damper with one hand while you try to tighten the bottom bolt. If this does not work try holding the top of the damper (see post #6) with a wrench while you tighten the bolt.

You could also install the fork cap to hold the damper so you can torque it.
 

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Sorry for the confusion here. If the damper is turning while you are trying to tighten the bolt in the bottom of fork try applying downward pressure on the damper with one hand while you try to tighten the bottom bolt. If this does not work try holding the top of the damper (see post #6) with a wrench while you tighten the bolt.

You could also install the fork cap to hold the damper so you can torque it.
I´ve tried everything you suggested now but nothing helps.

If I try to put downward pressure nothing happens no matter how hard i will press. About holding the top of the damper like in post #6 i can't see how it will make the damper not spin? That part just spins around by it self in the damper, no matter if the bolt is torqued or not? Same thing with the fork cap. I put only the fork cap on and that seems like it does the same thing when holding it with a wrench on top of the damper.

The thing is i can´t even remove the bolt. It had the same behavior when i removed it the first time, when I disassembled this fork leg, it just spun. I had to use a electric impact wrench(?) to loose it.

I haven´t put any torque to the bolt now, just a new washer and a little loctite and entered it by hand. I can´t even remove it with a electric impact wrench now. :idunno:

EDIT: I managed to torque the damn bolt by doing a home made fork damper holder with old stuff i had in the garage and it worked out
https://www.dropbox.com/s/tfp4vxbl2e5rilp/20140730_235500.jpg
 

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I´ve tried everything you suggested now but nothing helps.

If I try to put downward pressure nothing happens no matter how hard i will press. About holding the top of the damper like in post #6 i can't see how it will make the damper not spin? That part just spins around by it self in the damper, no matter if the bolt is torqued or not? Same thing with the fork cap. I put only the fork cap on and that seems like it does the same thing when holding it with a wrench on top of the damper.

The thing is i can´t even remove the bolt. It had the same behavior when i removed it the first time, when I disassembled this fork leg, it just spun. I had to use a electric impact wrench(?) to loose it.

I haven´t put any torque to the bolt now, just a new washer and a little loctite and entered it by hand. I can´t even remove it with a electric impact wrench now. :idunno:

EDIT: I managed to torque the damn bolt by doing a home made fork damper holder with old stuff i had in the garage and it worked out
https://www.dropbox.com/s/tfp4vxbl2e5rilp/20140730_235500.jpg
haha you sound exectly like me in this post:

http://www.fireblades.org/forums/honda-fireblade/108784-fork-help-needed.html


anyway, i wound up getting lucky with the impact wrench and it got it to grab the thread and get tight.. i like that tool you made but i'm not sure how it actually works since the bolt threads into the valve stack base which just sits in the bottom of the cartridge and is not "attached" to anything fixed in place... i guess if you could lock onto that and hold it solid or apply pressure directly to it and make it press against the retaining clip it might keep it from turning enough to get the bolt tight enough to keep pressure on it..
 

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haha you sound exectly like me in this post:

http://www.fireblades.org/forums/honda-fireblade/108784-fork-help-needed.html


anyway, i wound up getting lucky with the impact wrench and it got it to grab the thread and get tight.. i like that tool you made but i'm not sure how it actually works since the bolt threads into the valve stack base which just sits in the bottom of the cartridge and is not "attached" to anything fixed in place... i guess if you could lock onto that and hold it solid or apply pressure directly to it and make it press against the retaining clip it might keep it from turning enough to get the bolt tight enough to keep pressure on it..
Lol, i read your post and yes, we do sound alike ;)

The top of the bottom cartridge, is shaped and look the same as the bottom of my homemade fork damper holder. So when you put the tool inside the tube and they meet, the tool will be able to hold the bottom cartridge in place when I´m trying to torque the bottom bolt.

Before the tool was made, i was like "f*ck this, i´m using the impact wrench to torque the bolt" (it should only be torqued to 35Nm) so i thought it may damage something, i don´t know. But i manage to get hold of my self and made this tool instead.
 

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New to forum. Just purchased a 2003 954rr. That has been severely molested. My guess it was used as a stunt bike. But got it for a decent price. I plan on rebuilding the forks and shock before i ride it. This is a great thread. Thank you.
 

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Hey Doc, I just wanted to confirm that you did use the suggested 110mm air gap? The Honda manual (stock) says that it should be (if I'm not mistaken) 73mm air gap.

With that much of a difference in fluid (drastically less) how is she handling? Also, would you use 15w oil instead of 10w? I know it will stiffen everything up, but will it make that big of a difference in compression?
 

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Great write up. I have several question. I am about to swap fork springs. I got a set from Race Tech as well the 1.1 Kg/mm . they also came with a bag of washers. All I want to do is swap springs no rebuild nor oil.
Q1: how to remove the fork cap? the service manual said this but didn't make sense nor the pictures. they say to hold the rod adjuster case then loosen the lock nut. the image has the lock nut on top? you write up shows that I have to slide a wrench between the fork cap and spring collar
 

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I have an 01 929rr. Does the 954 run the same forks and will this instructions be the same for my 929? Thanks for posting! Very informative
 
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