FZRSupport: the FZROnline Archive

First of all I'm sorry about my english. It's not perfect.
I mounted -06 R6 rear shock on my FZR. It is fully adjustable and this mod will increase drivability to new century.
The mod is quite easy to make. Only special tool you need is spring clamps.

R6 shock is aproximately 5 mm shorter, but it does not cause problems.

Upper mounting hole must be drilled 10 -> 12 mm.

Lower end goes directly in the standard relay arm, as long as corner is slightly rounded like in the picture.

Sitting on the bike showed that R6 spring was little too loose. So I decided to fit FZR spring to R6 shock because FZR spring is stiffer. Maybe if you are lightweight and you like driving without passenger the R6 spring might be ok. Internal diameter of the springs are comletely identical. FZR spring is 1 cm longer. I cutted about 1,5 cm piece from each side of the fzr spring and grinded the top to flat.
Now both springs are same lenght



After 12000 km it is still working perfectly

That is a good write up. We've had a few people do this swap as well. I'm not sure what they did about the spring, but I think the only thing others have done differently is to add a bushing at the top of the shock to make up the difference in mounting width. Nice to have some pictures to go along with this swap.

And your English is quite good. Welcome aboard. Please be sure to add a thread to the intro section and tell us a little about yourself. Plus add some pictures of your bike. We like pictures here a lot.

Very cool. I need a softer shock for mine. Maybe I should go 06 R6 instead of the 99-02.

Did you really need to cut the spring to make it the same length though? Unless that made it a little more softer for you.

call me a noob if you want, but how in hell did you get the rear spring off?

1. Adjust preload to the minimum setting. This will make the removal and re-installation of the spring easier.



2. Remove rear shock according to the steps outlined in your factory authorized shop manual. Be sure NOT to disconnect any hydraulic lines from the adjuster itself.



3. Clamp the shock upright in a vise – with the adjuster at the top. There is often a set screw that goes through the adjuster casting and tightens onto the shock body to keep the adjuster from rotating. Mark the location of the set screw relative to the shock eye, then be sure to loosen the screws several turns before compressing the spring.



4. Set the spacer ring on top of the adjuster with the cut out lined up with the hose outlet and the beveled edge against the adjuster.



5. Now put the spring tool on top of the spacer ring putting the bolt through the spring tool clevis and shock eye and snug the nut down on it. Other than the bolt through the eye, the only part that should be in contact with the shock is the spacer ring. If the tool is touching the adjuster casting, then check to make sure the spacer and tool are completely upright before compressing spring.



6. To compress the spring, simply crank down the handle on the tool. Be sure the crank is well lubricated for easy operation. Compress the spring far enough that you will be able to pick off the retaining ring that’s on the shock body.



7. Remove the retaining ring and crank the tool in the reverse direction – reducing tension on the spring. Once the tension is completely released, remove the tool, spacer ring, preload adjuster, and finally the spring.



8. To install the spring, simply reverse the process. Once you’ve installed the shock back on the motorcycle (according to the factory authorized manual) you’ll need to properly set your “sag”. Generally speaking, you want the difference between fully extended and the rider sitting on the bike – ready to ride – to equal about one third of the total wheel travel. This measurement needs to be made from the axle to a fixed point on the chassis directly about it. Go Ride!

Great post. Its about time someone through some pictures together. Does anyone have the dimensions for the bushing to throw in here?

samtux- Did you notice any height difference after the swap?

You used the stock spring - and made it SHORTER? You now have fewer live coils = STIFFER.

If the stock spring is too soft, this may not be a bad thing...

95FZR600 wrote:1. Adjust preload to the minimum setting. This will make the removal and re-installation of the spring easier.



2. Remove rear shock according to the steps outlined in your factory authorized shop manual. Be sure NOT to disconnect any hydraulic lines from the adjuster itself.



3. Clamp the shock upright in a vise – with the adjuster at the top. There is often a set screw that goes through the adjuster casting and tightens onto the shock body to keep the adjuster from rotating. Mark the location of the set screw relative to the shock eye, then be sure to loosen the screws several turns before compressing the spring.



4. Set the spacer ring on top of the adjuster with the cut out lined up with the hose outlet and the beveled edge against the adjuster.



5. Now put the spring tool on top of the spacer ring putting the bolt through the spring tool clevis and shock eye and snug the nut down on it. Other than the bolt through the eye, the only part that should be in contact with the shock is the spacer ring. If the tool is touching the adjuster casting, then check to make sure the spacer and tool are completely upright before compressing spring.



6. To compress the spring, simply crank down the handle on the tool. Be sure the crank is well lubricated for easy operation. Compress the spring far enough that you will be able to pick off the retaining ring that’s on the shock body.



7. Remove the retaining ring and crank the tool in the reverse direction – reducing tension on the spring. Once the tension is completely released, remove the tool, spacer ring, preload adjuster, and finally the spring.



8. To install the spring, simply reverse the process. Once you’ve installed the shock back on the motorcycle (according to the factory authorized manual) you’ll need to properly set your “sag”. Generally speaking, you want the difference between fully extended and the rider sitting on the bike – ready to ride – to equal about one third of the total wheel travel. This measurement needs to be made from the axle to a fixed point on the chassis directly about it. Go Ride!

Or use 4 hose clamps instead of the tool.

only thing others have done differently is to add a bushing at the top of the shock to make up the difference in mounting width.

I forgot to mention about those bushings to the upper mounting. I don't remember dimensions but its ease to measure correct ones. I cutted them from bushing that is in upper mounting on a stock shock.

You used the stock spring - and made it SHORTER? You now have fewer live coils = STIFFER.
If the stock spring is too soft, this may not be a bad thing...

I know that cutting orginal spring will cause changes on spring constant. Cutting need was so little that I didn't notice any change on stiffness.

Did you notice any height difference after the swap?

I am using 5 mm shorter ''dog bones''. Ride height is little bit higher than stock.


I used this kind of spring clamps. Those are made for car springs. So I had to modificate to fit for smaller motorbike springs.

Very good info here!

just to clarify for those that don't know, by using a shorter shock and not changing out the dog bones to adjust for the change, you are effectively making a bike less responsive (slower to turn/change direction) but more stable. in other words, decreased handling. if you just cruise around, you may not notice much of a difference. but if you ride the bike hard on the twisties or track, you will definitely notice it -- and you will not like it.

a simple way to tell if you have changed the ride height of the rear of the bike when changing out the rear shock is to tape a string to the tail of the bike with a nut tied to the other end. have it dangle directly in line with the rear axle. have the bike on a rear stand to ensure it is straight up and down. mark the string with a marker to show a reference point of your choice -- center of the axle or top of the axle. when the new shock is on, compare where the mark is from it's original spot. if the mark is higher, it will make the bike more agile and less stable. (i raised my track r6 12 mm at the rear axle for faster transitions) and alternately, if it is lower than the original spot, the handling will be slower and more stable. if you lay the bike over all the way while riding, you will be scraping pegs sooner due to decreased ground clearance.

i'm not sure if the spring rate of a stock fzr shock and a stock r6 shock are the same, but i highly doubt they are. internal valving is going to be different too, as they are designed for very different bikes. the point i am getting at is -- all this is ok if the bike is used for regular riding on the street. if the bike is going to be subjected to high performance riding, such as trackdays or even very aggressive twisty riding on the street, i would suggest getting a shock designed for the fzr. when it comes to high performance riding, toying with a bike's suspension and geometry is asking for trouble if you do not know what you are doing.

i can see some people on here believing if they can simply pop in a newer, different bike shock, their bike will be better off. and that is simply not the case. i'm not coming down on the original poster, or anything. i'm just tossing this info out there for those that it may pertain to.

just my 2 cents...

Thats interesting about the spring. i didnt realize they were so close in size. the FZR spring is a considerably heavier spring rate though, so it could make a difference with heavier riders. Its not much of a problem with the stock R6 spring on my bike but Ive shaved a lot of weight off of it too. Are you using bushings on the top bolt? The FZR frame has a 10mm hole, but the R6 shock takes a 12mm bolt and the frame mount is about 3mm wider per side than the shock. These things are super simple to make though, or have made. Another note, you will need to shave the bottom mount of the shock a bit to make it clear the pivot arm. This just means that you need to shave off a few mms of material near the lower bolt hole for clear range of motion.

For those of you who want this shock with a YZF swingarm, I hope you can weld. the canister will hit the crossmember on the swingarm when compressed. Couple that with a softer shock and youve got damaged parts when you hit the road. But if youre a good welder, the shock can be turned 180* with a new fabricated frame mount and the canister nestles in beautifully behind the engine and you can still access the adjustment screws. Unfortunately, to remove the shock from this setup requires dropping the swingarm.

Good write-up!

This should be part of the WIKI...

95FZR600 wrote:Very good info here!

Samtux,
welcome, a good effort, thanks ReelRazor for the other tech background required for this project, nice to know I can have a day off once in a while and leave you guys in charge LoL

What we need now is all this info condensed into a HOW TO for the WIKI as a proper reference,

Ill try to write one up from mine this weekend