KAWASAKI 650 VERSYS RADIAL BRAKE MOD FOR GEN 2 ABS MODELS
Also applicable to non-ABS Versys and ER6
Abstract:
The more I looked at Versys lowering kits,, the less convinced I became that simply raising the forks up the maximum 22mm in the yokes is the ideal way to maintain geometry when lowering the rear 47mm via a lowering block.
If you must have a lowering kit, it seems that the ideal solution is shorter forks. You will give up the long travel length of the Versys fork, however I am a street rider and can live with less travel. Once you decide on shorter forks, radial brakes are easy and the quick fix for the compromised stock Versys brakes.
Sort of looking through the other end of the telescope – I wanted radial brakes, and lowered the rear to make it all work.
The solution was to use a Motowerk rear lowering block with radial caliper, (ABS in my case) Showa BP-SF (Big Piston Separate Function) Kawasaki ZX6R forks.
REQUIRED PARTS:
1. Motowerk WR lowering kit
Alternatively source a quality ER6 shock of your choice and do not use the Motowerk kit.
2. 2013–14 Kawasaki ZX6R forks with ABS option. See notes for other fork choices
3. ZX6R front axle c/w spacers to match your forks.
4. 108mm radial calipers. Caliper bolts are fine thread and not easy to find so make sure you get these too.
5. Nissin or Brembo 19mm radial master cylinder.
6. 1 ea. 115mm long wheel bearing spacer #90152-0242
7. 2 ea. #6500 sealed wheel bearings
8. 2 ea. 47 x 32 x 8mm seals. 7mm thick will also work
9. #34024-0103 - ER6 side stand or modify your existing stand
MACHINE WORK:
1. Bore the wheel to accept the larger 6500 bearings.
2. Bore one side of the wheel to clear the OD of the bearing spacer. The other side of the wheel is already large enough.
3. Bore the lower yoke to accept the larger fork tube. I had to bore 1mm for the fork I used. No worries as there is lots of meat in the Versys yoke. Versys top yokes are 50mm.
COST in USD
2013 ZX6R - ABS forks used on Ebay 500.00
Wotowerk lowering kit 127.00
2013 ZX6R axle used on Ebay 25.00
Machine work (cheap in Thailand) 39.00
03-04 ZX6R calipers, rebuild kit, powdercoat, EBC pads 180.00
Nissin radial master cylinder new on Ebay 117.00
Powdercoat clutch lever black to match M/C N/C at mates rates
Z1000 wheel bearing spacer (Thai price) 18.00
ER6 Kick stand (Thai price) 15.00
Wheel bearings and seals (Thai bearing supply house) 10.00
Re and RE tire (Thai rates) 3.00
Stainless ABS brake line kit ( 350.00 )
NOTES:
A great reference for parts cross reference is
http://www.cheapcycleparts.com/oemparts/#/c/kawasaki_motorcycle/parts.
Forks:
This mod works in conjunction with the Motowerk 47mm rear lowering kit, (or ER6 shock) and a 2013-14 ZX6R fork with ABS. The stock Versys fork is 780mm from axle centre to fork tube top, with a 12mm stick up in the top yoke, therefore 768mm effective length. When the rear is lowered 47mm, the front needs to be 721mm effective length. (768 – 47 = 721mm)
The 2013 ZX6R fork is 735mm axle centre to top of the tube, so a 14mm stick up will yield the same 721mm effective length. Unfortunately 14mm is not possible as there is not enough clamping area on the fork and 8mm stick up is the maximum. With 8mm stick up on the fork tube, the front is now 727mm effective length or 6mm higher than the rear compared to the stock geometry.
Fork tube stick up is measured to the top of the fork leg and not the cap.
A front fork 6mm higher than the rear is not ideal and I would prefer an equal height or slightly higher rear but this is the limitation of the fork clamping area at the yoke. A higher front fork length will result in a slightly slower turn in. I do not feel any discernible difference with the 6mm higher front, but I do not think my butt is that sensitive. One could make up with a 6mm taller 180/55/17 rear wheel, but the wider wheel will make it turn in slower offsetting any gain from the increased height.
The local practice, and the Motorwerk instructions, lowers the rear 47mm and the front can only be lowered 22mm maximum before running out of clamping room at the yoke. This yields a rear 25mm lower than the front, and is a large effect on the geometry of the bike. The 6mm lower rear using the ZX6R fork while not ideal, is much more acceptable and a far less effect on the overall geometry.
I have a 2011 (Gen 2) Versys 650 with ABS so I had to use 2013 – 14 ZX6R forks as at the time of writing this is the only years with ABS. If you have a non ABS Versys then you can use 2010 and newer ZX6R Showa Big Piston forks. I did not look into using non ABS ZX6R forks and welding on the ABS sensor bracket. Early ZX10 forks will work as well, but no ABS. Later ZX10 and Z1000 BP (big piston) forks have a too large OD fork leg to bore the lower yoke. Other forks may well work but I can only comment on what I used or researched so do your homework.
2013 non-ABS ZX6R forks has the boss for the ABS sensor and just not machined like Kawi does with other models. This opens up the shopping choices and you may be able to do better than my 500.00 cost. The Versys and ZX6R ABS sensor is identical
I weigh 78 kg and a bonous is that the 2013 ZX6R is the latest Showa BP-SF (Big Piston, Separate Function) fork, with a spring rate of .90 kg/mm and perfect for my 78 kg weight. Pre 2013 BP forks are .5N/mm heavier
See the Sonic spring rate calculator for your weight and riding style.
http://www.sonicsprings.com/catalog/calculate_spring_rate.php
Brakes:
All the 4 piston Japanese (and Triumph??) radial calipers use 108mm mounting bolt spacing. European calipers are 100mm so be sure to get the right ones. The 03-12 ZX6R Calipers all bolt up to the stock Versys 300mm rotors. 03-06 ZX6R are Tokio calipers. 07-10 ZX6R went to Nissins which are a much better caliper.
The 2013 to date ZX6R has 310mm rotors. If using these rotors, it will require either 5mm spacers under the pre 13 calipers or the mating calipers for the fork/rotors used.
At the time of writing I am not clear on the compatibility of the 2013+ Nissin monoblock calipers on the ZX6R with our 300mm rotors. I suspect if you use these calipers you will need the matching 310mm rotors, but this is unconfirmed
There is nothing to stop you from using 108mm Brembo calipers and a 19mm Brembo MC if cost is no option or bench racing bragging rights are important.
I had to use a 1mm washer under the 04 caliper mounting surface to clear the stock Versys 300mm rotor. I bought these calipers 3 years ago and not knowing any better at the time sourced 04 Tokio calipers that I rebuilt and powdercoated. Caliper rebuild kits were 78.00 USD from the UK, plus powdercoating. The Nissin is a better caliper so best to spend more for low mileage Nissin calipers. If I did this again I would not use the Tokio caliper
EBC – HH pads provide the grip and highly recommended for street use.
The stock Versys 14mm master cylinder is too small for the extra 4 caliper pistons, and a 19mm radial master cylinder would be best. The new Z1000 has a 19mm master with an integral trapezoidal reservoir for a stock look. For the best feel and control, a Brembo MC outperforms the Nissin. Cross reference the PN to see what will work for you.
I used a new Nissin 17.5mm 07-08 ZX6R radial master cylinder with remote reservoir, simply as the price was right on Ebay. Not having done enough research, the thought was that if it was good enough for the ZX6R it would be good enough for me but in retrospect I should have bought the 19mm master.
Wheels:
The stock Versys fender on a fabricated bracket will fit but looks splayed out from the front. A 2013-14 ZX6R or 2014 Z1000 front fender will fit the fork better, but it is too short and will allow detritus to be thrown up at the engine and radiator. Even with a fender extender it may be too short, given that Riders fit extenders to the longer Versys fender due to road debris. I have bought the Z1000 fender and am still working on this.
Wheel spacers are 13mm x 25mm ID and common to a host of Kawi’s so search the Cheap Cycle parts cross reference provided– mine are 2012 ZX6R.
The axle seems unique to the 2013 ZX6R and best to buy the axle c/w spacers
The wheel bearing spacer is nothing more than a 115mm long aluminium tube. I used a #92152-0242 Z-1000 spacer as it is made in Thailand. Do not assemble the wheel without this spacer or the bearing will fail. See the parts cross reference for alternate models
Axle OD is now 25mm VS the stock Versys at 20mm, so you need new wheel bearings and machine the wheel to fit. Bearings and seals were bought at a bearing supply house as there are international standard parts. No doubt the Dealer will be more expensive
Do not worry about machining the wheel for the larger bearings as the factory uses a common casting and does the same
Motowerk lowering kit:
Local Thai suppliers have ripped off Motowerk’s design for the lowering kit. I bought the genuine one from Motorwerk as this is a critical suspension bit and I am not about to trust some 80.00 Thai copy using an unknown alloy.
I have a 2011 Versys 650 with ABS, so I bought the WR series for an ABS Gen 2 Versys. If you have a Gen 1 or non-ABS then see the Motowerk website
https://www.motowerk.com
As I already had the custom sprung Yamaha R-1 shock, I used the Motowerk lowering kit. In retrospect I should have just bought a quality shock for an ER6 and would do so if starting fresh. Make sure that the shock is valved and sprung for your weight and riding style.
Tidying it all up:
I have Acerbis hand guards and had to water jet a 60mm longer bracket to clear the radial master cylinder. While I was at it I made the other side 20mm longer to get rid of the dodgy spacer.
Now that you have lowered it, the sidestand is too long. Either cut the end off the Versys unit and weld it back on shorter, or use a #34024-0103 ER6 stand. Motowerk sells a big foot kit to shorten the stand, but here in Thailand the ER6 stand is 15.00 USD so easy and cheap for me to buy a new stand
The stock rubber brake lines will work, but you are in so deep by now, you may wish to go for a set of braided ABS 350.00 (ABS is more expensive) stainless lines.
Protect those expensive new forks and brakes with a fork slider kit. I made my own simply because a ZX6R kit is not available in Thailand.
If you have long legs you might want to look at footpeg lowering blocks as the Rider triangle is now shorter– Motowerk makes some nice ones.
Adjust the front and rear suspension. If you do not know how to do this, get some help as it is critical to optimize performance.
Be sure to burnish those new brake pads.
ER6 AND NON- ABS VERSYS:
The ZX6R or ZX10 fork swap is a common non-ABS ER6 mod and the same process as described above, but with a Z1000 top yoke, and cheaper non-ABS radial forks.
With the advent of the 2013 and newer ZX6R with ABS it makes it easy for ABS equipped ER’s. The lowering kit is not required.
The non-ABS Versys mod is also the same mod but with the cheaper non-ABS radial forks.
Check the spring rate, and oil level, in relation to your weight and riding style.
Hoghead,
Chiangmai Thailand
Feb 2014
