Swap S2R 800 with 2003/04 GSX-R 1000 Forks
I switched my forks out for a pair of 2003 GSX-R 1000 Forks, which are adjustable, and a direct fit for the stock triples. This thread started on TOB by
b.h. GSXR Forks project, as well as the folks posting, were instrumental in the completion of this project, and to them I owe a big THANK YOU. This was my original thread on TOB,
Fork Swap with Radial brakes on an S2R...w/pic! , and
terrapete supplied the drawings for the spacers, which were fabricated.
While I was at it I also upgraded to 320mm rotors. The forks were freshly rebuilt, and came with calipers as well as spacers for 320mm rotors.
What you will need:
1. A bit of mechanical wit…smarts…courage…patience!
2. Torque wrench
3. Torx/Star Bit set
4. Lock-Tite
5. 24mm allen key, or M16 grade 8 bolt and 2 nuts (24mm allen substitute & cheaper)
6. Metric Sockets, Allen Keys and Wrenches (of course)
7. Smallish flathead screwdriver (for adjusting forks)
8. Spacers and fender adapter. (current Machinist making spacers:
Qfactor)
9. A set of GSXR forks, I don’t have specifics on years that were the same, I used ‘03/’04 1000s.
10. S2R 5 Spoke stock wheel (I am sure other years have the same dimensions, but I can’t verify this)
11. A device to support the bike, while you take off the forks. (I used a bike Jack)
12. Brake fluid
13. Extra Banjo bolt for caliper, single line(GSX-R uses a single and a stacked line configuration instead of two separate lines)
And what you will need to know:
1. GSXR forks are 6.35mm (1/4”) longer then the stockers
2. Torque Specifications:
a. Rotor Bolts = 24Nm
b. Top and Bottom Triples bolts for fork legs = 24Nm tighten 1-2-1 sequence
c. Caliper mounting bolts = 39Nm
d. Brake Lines = 23Nm
e. Brake Pad Guide = 16Nm
f. Axle bolt = 63Nm
g. Fork Axle Pinch Bolts = 23Nm 1-2-1 sequence
3. Suspension Settings:
a. Spring Pre-Load = 4.5 lines exposed (5 lines max, 0 line is top)
b. Rebound Damping = 6 counter clockwise clicks from stiffest position (stiffest is clockwise till stop)
c. Compression Damping = 11 counter clockwise clicks from stiffest position (stiffest is clockwise till stop)
4. How to bleed brakes
5. Apply lock-Tite
Here is how I did it;
The ’03 GSXR 1000 weighs in at 380lbs. dry, claims Suzuki, and the S2R weighs in at 381lbs. dry also, however weight distribution is different in that the monster is heavier in the rear then the GSXR.
These forks are about 6.35mm (1/4”) longer then the stockers.
Spacers.
First, jack the bike up off the front wheel and disassemble…disconnect brake lines, remove fork legs from triples, and wheel. After they are apart, remove the rotors from the wheel.
Now, clean that filthy wheel, and rotors!!
Add rotor spacers, then rotors, Lock-Tite and torque Star bolts to 24Nm.
Now insert the fork legs about 6.35mm(1/4”) above the top triple (be precise), and just snug the top and bottom triple clamp bolts to ‘hold’ the fork legs while you fit the pieces…axle should help straighten up the legs. Insert the axle nut (side with the big flange) into the left fork leg and Lock-Tite then torque pinch bolts to 23Nm….1-2-1 sequence. Now slide in the axle in thru the right fork leg it should align easily with the nut, if not readjust the fork leg at the triple. Do Not tighten the axle, just snug it and tighten the pinch bolts on that fork leg temporarily. At this point, I actually loosened the triple bolts to make sure everything was relaxed, as to avoid any fork binding.
Once you are sure of the fitment, tighten the triple clamps to 24Nm, if you removed the bolts apply some grease to them before tightening, bottom clamp to be tightened in a 1-2-1 sequence. Install the calipers, torque mount bolts to 39Nm. I was able to reuse my stock brake lines, however, I purchased a separate banjo bolt for the left side, and since I did not have a stacked brake line configuration on that caliper as the GSX-R does. I was also able to reuse my brake lines. Torque banjo bolts to 23Nm. Before you insert the wheel and rotor assembly, remove the brake pads from the calipers, as to not scare their surface when installing the wheel.
Next, loosen the pinch bolts on the right fork leg and remove the axle, we are ready to install the Wheel. Two sets of hands will help here as you insert the new washer on the right side of the hub and the milled spacer on the left side. Lift wheel into position and slide axle thru fork leg, before you contact the hub, insert the thin spacer (beveled side toward fork) then slide axle thru the hub. As the axle reaches the left side of the hub, insert the milled spacer replacing your OEM spacer, make contact with axle nut and tighten to 63Nm. Tighten pinch bolts on right fork leg to 23nNm.
Add brake pads to calipers, and tighten brake pad guide to 16Nm, snap in springs to guide. Now add brake fluid and bleed your brakes.
Install your fender adapter and fender…Lock-Tite all nuts and bolts.
You could skip the adapter if you have the Gixxer fender instead. I liked the look of the stock fender, so i removed the extra tab on the back of the fork to clean it up.
Time to reset the forks to the original factory settings, and then you can tinker with it until they feel right to you.
Here are some links I found that helped me:
http://en.wikipedia.org/wiki/Suspension_(motorcycle)#Damping_adjustment http://www.sportrider.com/tech/146_0402_susp/ http://www.gostar-racing.com/information/motorcycle_suspension_set-up.htm http://www.dynobike.com/motorcycle_suspension.htm
After some commuting to work, and a few back road romps, these forks are a well recommended improvement. I haven’t dialed them in yet, but I figure it will take some trial and error to complete the project. This process was very easy, especially with the help of my fellow DMLrs.
I should have taken more photos of each step, but didn’t realize it until I started this write up...too late. This seems to be a popular topic, so if you find some information in here that is unclear, or plain wrong, please let me know so I can update this post.
Fender adapter is finished.
spacer drawing, and fender bracket.
S2R GSX-R FORK SWAP Drawing File Current Machinist making spacers:
Qfactorbe sure to take multiple measurements. Double and triple check before you have spacers made. It is recommended to mock up the front end before having spacers made.
DISCLAIMER:
this drawing is for reference only, use them at your own risk.
GSX-R Forks That Fit:
'03-'06 1000cc
Spring Rate: Some members have complained that the NEWER fork spring rates are too stiff at:
.85 on GSXR 600
.10 on GSXR 750
.95 on GSXR 1000
However, the 2003 GSXR 1000 forks are .85, so check your fork spring rates before you buy a set of forks. Do a little research to see what should fit your weight and riding style first. You can always replace the springs and oil later if necessary.
Thanks,
RB
P.S. This is my thread it belongs to me, i started it and i keep it updated with all the info you great folks provide. So it lives where i live.
where did u get 320 mm caliper bolts . anyone give me specs of it?
