Racetech Spring Install Spacer?

[Wildcat_drvr]

Carlos,The people that write the manual say one thing.
Draftsmen draw the drawings and
The people that print the manual do as they please!
On page 4-49 look at the drawing
On the top right of the page.
Look at the second drawing down.
It shows the fine pitch at the top!
Can't make up their minds!
:rof:

Rich

 

[FinalImpact]

Carlos,The people that write the manual say one thing.
Draftsmen draw the drawings and
The people that print the manual do as they please!
On page 4-49 look at the drawing
On the top right of the page.
Look at the second drawing down.
It shows the fine pitch at the top!
Can't make up their minds!
:rof:

Rich

^^ ++5 Never even noticed that! Good Point! The TEXT IN THE FSM IS WRONG!

As a simple test, with spring "in Hand" push on it, watch what the "loosely spaced coils do" compared to the "tighter spaced coils". The loose open space coil areas compress first. THOSE GO TO THE BOTTOM! The manual SHOWS a proper diagram but the TEXT IS IN ERROR!!!!

Perspective: OEM FZ6 forks the the stanchion tube is INACTIVE! It does not move. That's why the aluminum spacer is at the top. Its a fixed stationary object.
- While riding the fork body (w/the wheel) is constantly moving up and down and this force is acting on the spring. The lower spring rate goes downwards towards the wheel as it will be compressed first! Then as the load increases the loose coils compress until the higher rate part of the spring begins to compress.

As said early - placing the spring in upside down {tight space to the bottom/Loose to the top} forces the WHOLE SPRING TO SLIDE IN THE STANCHION TUBE BEFORE IT CAN COMPRESS THE LOWER RATE part of the spring. Not only that it adds to the unsprung weight that must be controlled by the damping system. The FSM is wrong.

Another thread with the same level of confusion: http://www.600riders.com/forum/fz6-...-oil-question.html?highlight=springs,+spacer,


On the topic of gaining control - I offer these posts....

Compression rate is controlled by the damping system not the spring. So you can't fix a "DIVE" issue with a spring alone. You will be disappointed.

In short - spring rates are set by load imposed and the damping control does not effect the springs ability to carry a given load. That is - once you sit on the bike stationary - it is the springs that keep the bike suspended at a given ride height not the oil damping components (on our bikes).

Also, the stock fork springs are not a continuous (fixed) rate as they start at one value 0.77 mm/kg and rise to something like 1.2mm/kg under full compression. The biggest issue here is they need the preload adjusted to fix the initial sag of 45mm and reduce it 30 ~ 35 mm.

I urge you not to go crazy with the spring rate trying to fix a damping issue. Lack of damping is what is hurting the nose of the Fizzer. The lighter folks could likely get away with running emulators and fresh oil of higher viscosity if they adjust the springs pre-load for proper sag (I say this only from money saving stand point).

IMO - if you just cruise and want a smooth ride, shim the front spring, add emulators, and change the oil. If you ride aggressively I'd suggested a fixed rate for increased predictability (also the rear is a fixed rate) and run a front rate 0.9 mm/kg for geared rider of 215 or less.

Best money spent: if you can swing it - upgrade the forks to R6 or better. Its worth the effort and expense as it truly transforms the bike making it a pleasure to ride. Control in the corners and over uneven terrain will be improved substantially.

JJD952

I think there is a misunderstanding of what you need and what you're doing.

Spring load capacity sets the bikes carrying ability. Measuring the SAG will help determine how your current spring is performing in regards to the load placed upon it. i.e. how far does it settle.

Setting the ride height on our bike with the STOCK OEM shock is done by changing the preload. Reducing the space between the two spring perches reduces the amount the bike drops when a load is applied.

In the ideal world, we could change the length of the shock assembly effectively making the distance between the eyelets longer. Picture adding a turnbuckle to the end of the shock so we can change the total length of the shock without changing the space where the spring is installed (installed spring height). This would change the ride height while keeping the springs preload the same.

Specifically to address your problem:
The spring is just a spring. THe question is can it carry the load at the desired ride height? If yes, now we need to know if it matches the other end of the bike. If both are OK, we need to address how much damping control we have. If it compresses to quickly the bike will feel squirelly as the nose will seem light when the back settles too fast. If after being compressed the seat shoots upward hitting you in the rear, you need more rebound control. To much rebound control and the bike packs down over repeated bumps.

IMO the the bike in stock trim had horrid spring rate matching front to rear. Adding to that, the nose compresses at too fast of rate compared to the rear. This leads to rocking horse effect when you hit a bump or sink hole in a corner. Because the spring rates differ. Meaning, with me as part of the bikes mass, the nose compresses twice as far as the rear given the same load applied. Add to this, it collapses at nearly twice the rate (Exaggerating here). These compromises the riders control during cornering and braking.

How much do you weigh?

 

[Marthy]

Well after messing around with spacers I have my rider sag set
at 28.5mm. Sounds good to me. What do you guys think?

That would be a good track sag number IMO, if you ride on a lot of bumpy road I would back that off in the 40-35mm window. If you end up too stiff on the front compare to rear it might throw the balance off. When you brake hard you want to be close to bottoming the front suspension and use the full stroke.

As far as the spring goes... I firmly believe that the spring as absolutely no clue if it gets push from the wheel or the handlebars. That part most than likely get compress by rider sag. So I personally won't worry too much about it. I would worry much more about oil level than anything.

 

[overtheede]

Well I backed it off to 35mm after riding it just feels better for everday use.

 

[Carlos840]

Well I backed it off to 35mm after riding it just feels better for everday use.

What you can do is use a zip tie on one of your fork tube, as shown on the right tube in this picture:

This will allow you to have a visual representation of how much fork travel you are using. You want to use as much as possible without bottoming out.

With 32mm of sag this is the amount of travel i use under normal riding. If i do a very hard emergency braking (hard enough that the rear wheel is barely on the ground) it goes down to a bit less than half an inch. Which still gives me enough of a safety net in case i hit a bump while under braking to not bottom out.

All this info tells me that i am using pretty much all my fork travel which is ultimately what sag controls...

Don't forget to push down the zip tie next to the fork seal once you put it on.

 

[overtheede]

I was thinking about doing what you have on your bike. So like you said it will visually show how well it is performing.

 

[FinalImpact]

What you can do is use a zip tie on one of your fork tube, as shown on the right tube in this picture:



This will allow you to have a visual representation of how much fork travel you are using. You want to use as much as possible without bottoming out.

With 32mm of sag this is the amount of travel i use under normal riding. If i do a very hard emergency braking (hard enough that the rear wheel is barely on the ground) it goes down to a bit less than half an inch. Which still gives me enough of a safety net in case i hit a bump while under braking to not bottom out.

All this info tells me that i am using pretty much all my fork travel which is ultimately what sag controls...

Don't forget to push down the zip tie next to the fork seal once you put it on.

Carlos,
For kicks you might play with sliding the tubes up the clamps 4mm at a time and see what you think of the turn in.... My forks are 13mm shorter and their up the clamps 8mm. Still very stable at xxx should one be in that kind of mood!

 

[FinalImpact]

I was thinking about doing what you have on your bike. So like you said it will visually show how well it is performing.

I use Rip Ties (i.e. velcro cable ties), easy to see and can be used for cleaning bugs off the tubes before being eaten by the seals! :thumbup:

 

[overtheede]

Good idea on the velcro ties. But either one should work great.

 

[rk8950]

Put the stock spring/spacers in with the cap on top. Don't screw it in... let it rest there with the suspension fully extended. Measure the distance between the cap and fork tube... that's your preload.

From there you might need to go a bit more or less depending of your rider sag number. Aim for 35-40mm rider sag. The kit should have come with some washers to fine tune...

Hope it help.

Are you measuring from the top of the cap or the very bottom where it sits on spacer? Looking at instructions which covers a variety of different forks I think it is saying measure from bottom. Or do you measure from the top of the cap where it would meet the fork tube?

 

[rk8950]

Ok I got it done I ended up with 31mm rider sag. I can definatly tell it sits higher in the front. I will play around with fork height when I get a chance to ride it to see how it turns. I was at 40mm rider sag with stock springs.

 

[iSteve]

Static sag is usually the amount of sag with rider. This is the important measurement. Moving the forks up and down in the the triple tree should be adjusted (but not needed) after you set the sag. If your sag is around 33mm give or take a little then fork caps even with the top clamp should work for any street riding.

 

[Carlos840]

rk8950: 31mm static sag is perfect, check your static sag, which is measured without the rider and what you have. If it's around 20mm you are perfect!
You should also setup your rear shock if you haven't done it yet. If you are around 185lbs the correct setting to get in the 30mm rider sag range is 5. I would not go higher than that as you end up with 0 static sag which is not recommended.

iSteve: Static sag is not the mount of sag with rider, it is the amount of sag under the bike's own weight, sag without a rider.

 

[rk8950]

I have my rear set at 6.

I have rode mx for nearly my whole life and set sag on a whole lot of bikes. We have always referred to it as rider/race sag and free sag(just weight of bike no rider). I think racetech may have mis printed it in their directions but maybe thats what they call it. No biggie though we all know what it is:thumbup:

Carlos I also put some of 717 grips on my bike that you had tried. I love them, big improvement over stock

 

[Carlos840]

I have my rear set at 6.

I have rode mx for nearly my whole life and set sag on a whole lot of bikes. We have always referred to it as rider/race sag and free sag(just weight of bike no rider). I think racetech may have mis printed it in their directions but maybe thats what they call it. No biggie though we all know what it is:thumbup:

Carlos I also put some of 717 grips on my bike that you had tried. I love them, big improvement over stock

yeah, the general nomenclature is usually Rider/race sag for sag with rider, and static/free sag for rider less sag.

The 717 grips are great, but they do wear very fast you can expect to have to change them every 5000 miles i think. But hey, they are cheap and the grip is so much better i don't think it's a big deal!

 

[iSteve]

rk8950:

iSteve: Static sag is not the mount of sag with rider, it is the amount of sag under the bike's own weight, sag without a rider.

I guess it really doesn't matter what it's called as long as both parties agree. I've always gone by Static sag=with rider / Free sag=without rider. I've also heard it called Race sag=with rider and even loaded and unloaded sag.

Whatever, the with rider sag is the important number unless you are calculating spring rates. Then you would try different springs until you get whatever sag ratio setting you are going after. I think it's easiest to use the spring manufacture suggested rate and then set the with rider sag and go enjoy the ride.