Pulled the trigger on R6 forks - a few questions

[zixaq]

So I saw a set of forks from an '03 R6 come up locally and nabbed them. $280 for the forks, calipers and axle, so I'm feeling pretty good about that. I have a couple questions for people who have done this:

1) Brake lines: Did you go with stock length, or get them a bit longer? I'll be replacing with SS lines as long as I'm changing things. (also not sure what color to get with a silver FZ6 , brake accents are blue)
2) Spring: The .85 kg/mm stock spring seems a lot closer to where it should be, but at my weight, it seems like the recommendation is closer to 1 kg/mm. Has anyone over 200 lbs done this mod, and did you swap springs?
3) Shims: Anyone still selling these or have an extra kit laying around?
4) Brakes: Worth rebuilding the calipers since they're off and apart already?
5) Anything I should check or watch out for before I start working? I'm planning on replacing the fork oil first at least, probably with 10 wt.

 

[KHarper4289]

So I saw a set of forks from an '03 R6 come up locally and nabbed them. $280 for the forks, calipers and axle, so I'm feeling pretty good about that. I have a couple questions for people who have done this:

1) Brake lines: Did you go with stock length, or get them a bit longer? I'll be replacing with SS lines as long as I'm changing things. (also not sure what color to get with a silver FZ6 , brake accents are blue)
2) Spring: The .85 kg/mm stock spring seems a lot closer to where it should be, but at my weight, it seems like the recommendation is closer to 1 kg/mm. Has anyone over 200 lbs done this mod, and did you swap springs?
3) Shims: Anyone still selling these or have an extra kit laying around?
4) Brakes: Worth rebuilding the calipers since they're off and apart already?
5) Anything I should check or watch out for before I start working? I'm planning on replacing the fork oil first at least, probably with 10 wt.

What year FZ do you have?

Over 200lbs BEFORE gear - you might want some stiffer springs. This mod is going to be a game-changer without them, but if you want to maximize your investment, you might want some slightly heavier springs (or oil)

Dako81 sells the shim kits for around $80

Wouldn't mess with the brakes, unless you have a good reason to believe they need rebuilding.

 

[zixaq]

What year FZ do you have?

Over 200lbs BEFORE gear - you might want some stiffer springs. This mod is going to be a game-changer without them, but if you want to maximize your investment, you might want some slightly heavier springs (or oil)

Dako81 sells the shim kits for around $80

Wouldn't mess with the brakes, unless you have a good reason to believe they need rebuilding.

2004 FZ6. I'm about 235 without gear. Sadly, the racetech springs in my current forks won't transfer over.

 

[KHarper4289]

2004 FZ6. I'm about 235 without gear. Sadly, the racetech springs in my current forks won't transfer over.

You'll definitely want something stiffer in there. Heavier oil might be enough, your call on the finances though.

 

[FinalImpact]

I've been up to 200 and thats a bit much on .85 kg/mm springs from the past.

Oil wt does not replace spring rate. All I can say is rough roads are ok w 7.5wt. 10 is useless on adjustable forks it will beat you death defeating the need to adjust correctly. 5 is good and very reactive for good roads.

JM2C but S2 FZ calipers are better than 03 R6. The reason being the leading piston is smaller on the FZ and this promotes even pad wear from leading to trailing edge of the pad.

Equal sized pistons (old r6) tend to tip the leading edge of the pad in more and wear the pads at an angle.
So, rather than roll the dice on 03 calipers, maybe invest in S2 FZ parts from a low mileage take off???

Also, you can cheat with the oil fill level to compensate for spring rates until you can afford them. Equally over filling each leg decreases the air volume which can reduce some nose dive. Still, not a substitute for the proper rate spring.

 

[zixaq]

I've been up to 200 and thats a bit much on .85 kg/mm springs from the past.

Oil wt does not replace spring rate. All I can say is rough roads are ok w 7.5wt. 10 is useless on adjustable forks it will beat you death defeating the need to adjust correctly. 5 is good and very reactive for good roads.

JM2C but S2 FZ calipers are better than 03 R6. The reason being the leading piston is smaller on the FZ and this promotes even pad wear from leading to trailing edge of the pad.

Equal sized pistons (old r6) tend to tip the leading edge of the pad in more and wear the pads at an angle.
So, rather than roll the dice on 03 calipers, maybe invest in S2 FZ parts from a low mileage take off???

Also, you can cheat with the oil fill level to compensate for spring rates until you can afford them. Equally over filling each leg decreases the air volume which can reduce some nose dive. Still, not a substitute for the proper rate spring.

Interesting. All the mod descriptions I've read said to get the R6 brake calipers if doing the swap on an S1. They didn't cost me much extra, so no heartbreak if I end up not using them.

It actually looks to me like the pistons are different sizes on these calipers.

 

[FinalImpact]

True - S1 calipers will not fit S2 fork or R6 fork. But S2 caliper do fit R6 forks!

As for brake lines, stock S2 brake lines are the perfect length.

 

[zixaq]

True - S1 calipers will not fit S2 fork or R6 fork. But S2 caliper do fit R6 forks!

As for brake lines, stock S2 brake lines are the perfect length.

Good to know. Stock length will also work with FZ1 or FZ6R handlebars? I might swap out eventually, and would rather not have to buy new brake lines.

 

[FinalImpact]

Yes. Unless you add bar risers...
Also, turn in is improved by sliding the stanchion up the triple 6-10mm.

With the Dako kit you're set. The S2 group had to slot the fender 0.75". Im not sure on the S1.

Throw some veener calipers at the pistons. The difference is only a few mm.

Get it together and measure the bike and bike plus rider sag. Over 10+ years on those forks, who knows what springs are in them.. .. ..

Bike should get: 5 - 10mm
Bike & rider: adjust to 25 - 35mm sag

If you can hit that range w the springs it has, try it!

 

[motojoe122]

I've been up to 200 and thats a bit much on .85 kg/mm springs from the past.

Oil wt does not replace spring rate. All I can say is rough roads are ok w 7.5wt. 10 is useless on adjustable forks it will beat you death defeating the need to adjust correctly. 5 is good and very reactive for good roads.

JM2C but S2 FZ calipers are better than 03 R6. The reason being the leading piston is smaller on the FZ and this promotes even pad wear from leading to trailing edge of the pad.

Equal sized pistons (old r6) tend to tip the leading edge of the pad in more and wear the pads at an angle.
So, rather than roll the dice on 03 calipers, maybe invest in S2 FZ parts from a low mileage take off???

Also, you can cheat with the oil fill level to compensate for spring rates until you can afford them. Equally over filling each leg decreases the air volume which can reduce some nose dive. Still, not a substitute for the proper rate spring.

Jumping in on this....
I have a set of R6S calipers for sale, just have not posted it yet. Pm me if interested.


Sent from my iPhone using Tapatalk

 

[zixaq]

Haven't heard back from dako on the fittings. Seems like I can make do with some shim/washers from McMaster Carr for the axle and brake spacers, even if the axle solution is less elegant. Where I'm still stuck is the (admittedly less important) fender spacer.

Anyone found a solution for this without having something machined? I'm checking with an old friend to see if he can make them, but if not . . .

From what I can find, the S2 brake calipers and all the R6 calipers look identical to me, but I'll try to run them by the shop tomorrow and check the piston diameter. I'll probably just stick with these since I already have them. (Only problem is the blue accents)

 

[zixaq]

w00t! dako is still selling the fittings, so that's solved.

Now the most important choice: What color brake lines and fittings for a silver FZ6? I'm leaning towards the translucent blue, since there's some blue accents on the R6 brakes and forks anyway.

I'll get on the horn with RaceTech sometime today and see what they recommend for springs. I'll post up if it's anything surprising, but I expect using their spring rate calculator for an R6 using the FZ6 bike weight should get pretty darn close.

Edit: After chatting with Lou at RT, he said the best solution was to just match the recommended spring RATE for the FZ6, and ignore the R6 calculator. So I'd be looking at a .95 kg/mm over the stock (assuming it's stock) .85. That's close enough that I think it's worth a try with what's in there first. Does anyone have a picture/measurements of a confirmed stock R6 spring?

 

[FinalImpact]

I think mine are stock but honestly don't know. I recorded free length, coil count, coil diameter.

The thread is Something Black
I think.... search for JJD952 spring

Paste...
.Post#32 of Something Black - Links and info:
To be edited often adding links, data, Problems, Solutions, and well - what ever comes to mind. . .

FORKS & SUSPENSION:
First thanks in advance all of you folks that did the R6 fork mod!!! Here are some helpful links in one place for reference (mainly me :/). . .

R6 Spork
R6 Fork Install Another One
Help Need Correct PN for 2004 R6 Axle
R6 Forks Arrived, Couple of questions
Hyperpro lowering springs
HyperPro Springs installed
Front fork mods pita factor vs payoff
Bolt-r6-fork-upgrade
Ricor Intiminator fork mod
R6 Fork Mod Spacers


2012-02-11 My fleebay R6 Forks:
**********************************
Oil is pretty clean for 3000 mile forks. It has a gray haze to it and blackness at the beakers bottom. Some metalic bits. . .
Spec says 490mL should have come out. I got 470mL.
Another observation is that the coil spring winding is supposed to be wound tighter at the top. Nada - equal throughout the entire coil.
As found:
Coil Dia= 4.72mm 0.186"
Coil spacing = 9.26mm .366" between coils
Free length = 252mm spec: >244 <249 (9.81" - 9.62")
Coil count: 7coils/10cm or 17 coils not counting ground ends.
REFILL: hahaha magically the 1 pint bottle is 473mL
Without the spring and spacers and washers in the way and with the tube collapsed it should measure from the top 106 mm (4.17 in).

View attachment 40352 View attachment 40353 View attachment 40354

My hi-tech tool to keep the dampening rod from disappearing. Also notice how thin the washer is that bucks the load of the spring (right under the cap).
View attachment 40359 View attachment 40360


So i have to ask; have the springs been replaced? The cap has been wrenched on (before I got them) and there is lint balls in the caps threads. Would Yamaha leave lint balls? I'm glad I looked and at least we kinda have a starting point if I do end up swapping springs later.

Oh - going back in is 7.5wt oil cause that's what I have! Book calls for 05wt.
As for cleaning; I grabbed an extra pint of oil to cycle through and rinse, shake and loosen the sediment. It seems to be working. Also, leaving the fork upright allows oil to drain from the valving and pool so it can be dumped out. Leaving it inverted traps it and nothing really drains once a bulk of the oil has been dumped. So let them sit and then dump out what pools in the bottom a couple times and then invert them to let the debris seep out.

You really want to pay attention to the measurement of the jamb nut to the dampening rod (11 mm (0.43 in)). The distance is critical so the rebound adjustment is the same between the two forks and centered for full range of use. I didn't take a picture of it, but there is an aluminum rod inside of the dampening rod that moves up and down controlling the rebound when the adjuster in the cap is turned. Once the nut is at 11mm, tighten the BLUE collar onto the jamb nut so it doesn't move in relation to the rods end.

Last little note on this topic; you must apply mild pressure on the cap to engage the caps threads when mating the two together.

EDIT: 2012-02-19, installed R6 forks WORK IN PROGRESS GOTTA GO!
**********************************
Finally checked the sag on the front and rear suspension right before removing the stock forks and replacing them. Sag is a simple measurement of suspension fully extended vs the suspension at its average height after being settled from both an extended position and a compression return. You average the 2 numbers it settled at to remove stiction which is the drag of all of the components. Sag = "difference from fully extended" - "average settled height".

Anyway my 08 with 8k miles on it came in like this with me at 188lbs w/out gear:
Front sag = 43mm (compresses 1.7" from me sitting on it)
Rear sag = 29mm (compresses 1.1" from me sitting on it)

R6 forks installed:
Front sag = 31mm and adjustable +/-20mm
Rear sag 29mm

Several articles say that 25 to 35mm is good for the street while racing applications head closer to 20 to 25mm. So this is my starting point for this season and to be adjusted as needed. . .

As you can see the stock front springs are dropping a good deal just from me sitting on it and its soft progressive rates compress easily hence the higher numeric stag# in the front. Having it closer to matching (31) should make it take bumps and surface imperfections in the corners much better if both ends of the bike have closer to the same sag and spring rates.


A 2004 R6 was the doner bike with 3400 miles on it. The rates for the front are:
Spring rate K1: ___________8.3 N/mm (0.83 kg/mm, 46.49 lb/in)

vrs stock FZ6 dual rate of:
Spring rate K1: __________7.40 N/mm (42.25 lb/in) (0.75 kgf/mm)
Spring rate K2: __________11.80 N/mm (67.38 lb/in) (1.20 kgf/mm)

What does all this mean: The FZ has 5.1" of travel. The second rate comes into play near the end of those 5" when the nose is diving hard under braking (1.20 kgf/mm). Granted many are buying Race Tech Springs to firm things up and most are opting for 0.95kg/mm. But as most of you know the stock FZ springs use up a good 3.5" of travel over minor bumps and braking.
I know I may end up swapping springs but these forks make it easy to dial in the sag as well as adjust both compression dampening and rebound dampening. Time will tell where we land with the springs. . . How will this impact cornering; with less initial rake from the nose being higher it will change how it feels. However, these forks are a 1/2" shorter 12.5mm. SOoooooooo, if you were to look at the sag vrs ride height -the numbers really come back to the same numbers in terms of rake or angle on the nose because the relationship of the steering head to the axle is very near the same as it was with the softer springs (@43mm) vs 31mm (& shorter forks 12.5mm). Make sense?

Edit: hey if you don't want to swap parts but want to help the bikes nose, at least add some new spacers to the front springs to fix the sag so you can ride safer. . .

**********************************
2012-10-17
Rear R1 shock came. The prices on fleebay are so low its like how could you not play around a little???
I need to swap springs and grind on the upper shock mount and plastic. In the mean time here are some things to think about.

=====================================

2008 FZ6 Rear Shock:
Eye to eye: 300 mm (11.82")
Travel: 50mm (1.97")
Setting #1 light: 175.2mm (6.90")
Setting #7 firm: 165.8mm (6.53")
Installed length MANUAL: 172.0 mm (6.77 in), doesn't say what setting tho.

Range of preload: 9.4mm (0.37")
Coil OD: 77.6mm (3.055")
Coil Dia: 11.76mm (0.463")
Spring free length 185.0 mm (7.28")
Spring rate K1: 12.99 kgf/mm (727.45 lb/in), 127.40 N/mm

=====================================

2003 R1 Rear Shock:
Eye to eye: 300 mm (11.82")
Travel: 65 mm (2.56")
Setting #1 light: 175.2mm (6.90")
Setting #9 firm: 165.8mm (6.53")
Installed length MANUAL: 162.5 mm (6.4 in), doesn't say what setting tho.

Range of preload: 9.4mm (0.37") /Min = 1, Ship @ 4, max = 9
Coil OD: 77.6mm (3.055")
Coil Dia: 11.76mm (0.463")
Free length 176.5 mm (6.95 in)
Spring rate K1: 8.83 kg/mm, (504 lb/in), 88.3 N/mm

SHOCK dampening from fully turned in:
Rebound damp min: 32
Reb Standard: 15
Rebound damp max: 1

Compression damp min: 20
Compression damp stand: 15
Compression damp max: 1

=====================================

So my FZ is set on #5. From this I will measure the installed height at the #5 position and adjust the R1 body to this distance. Looking at the info I gathered this will be a bit of a challenge and may require some adjustments to the spring seat/retainer as the area for the spring is not the same between the two bodies/adjusters. Hopefully this is obtainable.
The other issue is the R1 Shock assembly has more travel. The Shock needs to be fitted to the bike WITHOUT the spring and then exercise the entire range of travel so I know how the chain will be affected and where and what is going to hit if anything. It may be worth while to add a solid spacer under the biscuit to limit the travel so its equal to the FZ shock.

Simple math indicates the this shock would allow 6.6" of travel vs 5.1". is that a problem? IDK!
If the shock allows me to set the installed height equal to my current setting #5, I think we'll be off to a good start once the springs are swapped. Also the bushings will need some help too!

FZ #1 light: 175.2mm // R1 #1 light: 167mm
FZ #7 firm: 165.8mm // R1 #9 firm: 159mm
--------------------------------------------
- - - - - - - 9.4mm - - - - - - - 8mm

Although the range is near the same, the actual distance between the spring lands is where the issue lies. Well unless you opt for the custom wound spring! Mind you I'm using someone elses measurements for the Fiz shock as mine is still on the bike and difficult to measure. All I'm saying is be prepared to switch up the spring retainer to get the proper pre-load so the setup has a reasonable sag and stands a chance of working right.

=====================================

 

[zixaq]

Halp! mod no werk.

So I attempted to put the R6 forks on today. TL;DR: My brake calipers aren't spaced right.

To make them fit centered, I'd need an ~8 mm spacer for each bolt, and the spacer that typically comes with the "kit" to do this is only ~2.5 mm. The inside pad is pressed hard against the rotors when I bolt them on.

My first guess is that maybe the calipers are wrong? But they *look* like the calipers in the 2003 R6 service manual, and the brake pads I bought for that model fit perfectly. Is there any way to be sure?

Another possibility is that the forks are wrong, but again, they *look* exactly like what's described in everyone's posts here. It's possible it's a slightly different year with different caliper brackets? Calipers fit just fine on the fork legs, they're just still too wide. If both calipers and forks are the wrong year, they're pretty damn close and I just might try to find a few more washers to make it fit.

I checked the thickness of the spacers for both the brake caliper and the axle, and they match the spec sheets posted online. I tried switching the spacers around (contrary to dako's labeling) just to make sure, but it made no difference. The axle is much shorter than the space it extends through, so it can't be holding things apart. The wheel is a very snug fit with the spacers in, and it could be pushing the forks apart a little bit, but nowhere near 16 mm.

Basically, I'm stumped. Any ideas where I went wrong? Is it okay to find some more spacers for the calipers? Anyone else run into a similar issue?

---

There is some good news aside from the fitment problems:
The forks have been resprung with an aftermarket spring from RaceTech, so there's some hope that it'll work. I'm sending the measurements to RT to see if they can tell me what the spring rate is.
The brake calipers look fantastic, which is good, because the company I ordered the rebuild kits from sent me one instead of two. . .
The fork oil is changed and the brake calipers are cleaned, so when I try this again it will be much faster.
I had the forethought to save the brake line swap until LAST, so when they told me I had 30 minutes to get my bike together and get out, I actually managed to get the old forks back on and working.
Also, I moved the triples down 5mm on the regular forks and that feels better all by itself.

---

For the cognoscenti, the spring details:
Free spring length: 275 mm
Spacer length: 75 mm
Spring dia: 38.5 mm
19 coils
Coil dia: 4.9 mm
coil spacing: 10 mm (between surfaces, 15 mm total)

 

[FinalImpact]

Re: Halp! mod no werk.

Post up some pictures of the calipers and forks.
0.100" spacers should do the trick. I would not want a lot of spacers all hanging on those bolts.

I have some caliper and fork pictures. I'll post once yours aee up to compare...

 

[zixaq]

Re: Halp! mod no werk.

Post up some pictures of the calipers and forks.
0.100" spacers should do the trick. I would not want a lot of spacers all hanging on those bolts.

I have some caliper and fork pictures. I'll post once yours aee up to compare...

The forks are at the garage, so no dice there. I'll try to get some of the calipers up. The standard spacers weren't even close.

 

[FinalImpact]

Re: Halp! mod no werk.

The forks are at the garage, so no dice there. I'll try to get some of the calipers up. The standard spacers weren't even close.

Did you try both sides?
The reason I ask is perhaps the axle spacers were placed on the wrong side?? This could the account for the distance you speak of. I ask about both sides as checking both could show one needing a postive offset while the other needs a negative offset. Maybe?

The spacer with the recess should be on the left or stator side of the engine vs the clutch side.

This post has a few pictures at post 7...
Brake bleeding - how too!

 

[zixaq]

Re: Halp! mod no werk.

Yes, I tried swapping the axle spacers, although it didn't actually matter for this. The difference is that the way they're designed, the axle head is slightly recessed and flipped it's flush with the fork. The original try was with the spacer with the groove (that fits the axle head) on the clutch lever side of the bike. Forks both had the raised numbers on the fork leg toward the inside, so I'm pretty sure they were on the correct sides? I honestly would have tried swapping the forks around, but the garage closed at six and I had to leave.

I have a day off on Wednesday. Hopefully I can get this figured out by then.

 

[FinalImpact]

Re: Halp! mod no werk.

FWIW: R6 fork; the axle enters from the other side than the FZ. So the R6 bolt is on the right (brake side).
Also the forks are marked left and right.

 

[zixaq]

Re: Halp! mod no werk.

FWIW: R6 fork; the axle enters from the other side than the FZ. So the R6 nut is on the right (brake side).
Also the forks are marked left and right.

That is consistent with the way I had them on, which is nice to have confirmed. I did not see the left/right markers.

So, confirmed I had the forks on the right way, axle in the right way (it doesn't fit backwards), and which side the axle spacers were on was irrelevant. Still have a problem with the brake caliper spacing though.

Hopefully someone has had a similar experience and can tell me where I'm messing up.

Edit: Starting to second/third guess myself. When I got the calipers on the front tire wouldn't spin, and the rotors looked way out of center in the calipers. Maybe that's normal, but if I screw up my bike I don't have any way to get to work, so I stopped. Something seemed wrong, and I've learned to listen to that little voice the hard way.