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The Fork Swap Informational Thread!

121710 Views 398 Replies 30 Participants Last post by  AusEr6guy
Hello all!

After seeing djrussell and kojiiro's successful fork swaps on their 650's and their testimonies to how amazing it feels, I have decided to switch from the Gold Valve Emulators to the swap myself. I'm not sure how long this will take, as there is so much information out there. At first, I was planning on just PMing the people who completed the project with any questions I have (As there will be many), but I think a thread that I continuously build that includes resources, questions and answers, tips, etc would be more useful to me with more people seeing it, and more useful for others interested in the swap.

Listed below are the different sections, and these will be added to and updated as much as I can with my own research and with the help of you wonderful people. :)

If you have any suggestions for what to add or change, feel free to let me know! If anyone wants to take an active part in this, do some searching of your own and send any information you have to me with its source.

Hopefully this thread turns out useful to both me and any others. Please, post every question you have- the more the better.

Introduction:
Why do a fork swap? First: Suspension. The 650's suspension is mediocre at best, with the rear shock being cheap and the front forks being horribly oversprung and based off old technology. While improving the rear suspension is as easy as buying a rear shock that's valved and sprung for your weight and riding style, the front is not as easily overcome due to the nature of forks (Can't just buy some random Ohlin's forks and expect them to work at all). The easiest improvement to the front end is correctly sprung springs- as easy as taking the forks apart a bit and sticking new springs in.

Past springs, what's the problem? The forks are based off of old damper rod technology, in which damping(Resistance to movement) is influenced by how fast fork oil can flow through holes on a rod within the fork. That's it. As fork travel velocity increases (Harder bump), the more damping is provided, due to the fact only a limited amount of the fork oil can travel through the holes at one time. Not only is this damping not adjustable, but as the velocity doubles, the damping effect quadruples- this basically means the forks must be designed with a compromise in mind, where low-speed damping is way too soft and high-speed damping is way too harsh.

How to we solve this? In this case, we swap out the forks with another type that is much more effective: cartridge forks! These forks rely on valving to provide damping. Holes in cartridges within the fork provide low-speed damping, but as velocity increases, shims on the cartridges start to bend and allow more oil to flow through, allowing for much more tunability and the ability to create great damping for both high and low-speed fork movements. On top of this, the amount of oil flowing through the small holes and to the metal shims is adjustable, allowing a large range of adjustment. Basically, this translates into the possibility of a fork that is perfectly tuned for your needs. Sound great, right!

How do we do the swap? Good question! Basically, we take forks off of other, higher end bikes (Namely older generation 636/ZX6Rs or ZX10Rs) and put them on ours. Sadly, it is a bit more complicated: new triple trees, brakes, possible wheels and handlebars and master cylinders are needed, along with a few other things. Don't worry though, everything is explaining below, and if you're up for it, you can get an amazing new front suspension setup by doing this.

Do I get anything else? Beside cool, anodized inverted forks, you have the opportunity to get vastly improved brakes. Think your 650 brakes are good enough? Trust me, you won't once you try some sexy Nissins off a ZX14R!

Are there any other options? Sure! If you don't want to partake in this fun, you can buy these nifty things called "Gold Valve Emulators" or "Intimidators". Look them up, they basically provide cartridge-like qualities for your fork, albeit at the expense of some performance (Compared to true cartridge-based forks) and adjustability. You could also buy cartridge internals that basically convert your forks into adjustable cartridge forks, which is much easier than a swap, however those are very expensive ($1000-$1500). Either that, or just buying a bike with some good forks already installed is an option.

After all this, are you still interested? If so, continue on...

Options/Parts:
This is where any parts needed for the swap will be listed. On top of this, average prices, locations to buy along with different options (Such as different triples to use) will be listed

Triple Clamps:
These are the things that connect the fork/wheel assembly to the rest of the bike through the frame. There is an upper triple clamp that you connect your handlebars/clip-ons to, along with a lower triple clamp that has a rod attached to it that fits in the frame- both of these have bearings installed that allow them to be rotated for steering. Because the forks you will be using will be a different size/type of fork, new triples must be used to accommodate the different sized tubes.

All combinations of the triples listed should work together in terms of fork offset/location

Upper Triples
Z1000
Average Price: $100
Usable Years: All
Upper Clamp Diameter: 50mm
Handlebars: Allows stock use for 12-15 650s
Recommended Fork: 636 or ZX10R
Difficulty to Find: Medium-High
-Small cutting required for 12-15 650s to allow full rotation between steering stops(Refer to Kojiiro's build guide, post 3)

Versys 650
Average Price: $100
Usable Years: All
Upper Clamp Diameter: 50mm
Handlebars: Must use clip-ons (12-15 650s: Must use clip-on risers)
Recommended Fork: 636 or ZX10R
Difficulty to Find: High

636
Average Price: $75
Usable Years: 03-08
Upper Clamp Diameter: 50mm
Handlebars: Must use clip-ons (12-15 650s: Must use clip-on risers)
Recommended Fork: 636 or ZX10R
Difficulty to Find: Low

ZX10R
Average Price: $75
Usable Years: 04-10
Upper Clamp Diameter: 50mm
Handlebars: Must use clip-ons (12-15 650s: Must use clip-on risers)
Recommended Fork: 636 or ZX10R
Difficulty to Find: Medium-Low


Lower Triples
Z1000
Average Price: $200
Usable Years: 03-06 (Other years possible, but not confirmed)
Lower Clamp Diameter: 52mm
Steering Stops: Match stock, no welding required
Recommended Fork: 636
Difficulty to Find: Medium-High

Versys 650
Average Price: $100
Usable Years: All
Lower Clamp Diameter: 52mm
Steering Stops: Match stock, no welding required
Recommended Fork: 636 or ZX10R
Difficulty to Find: High
-Can be milled out to 54mm (2mm larger) clamp diameter to be used with ZX10R forks

636
Average Price: $50
Usable Years: 03-04
Lower Clamp Diameter: 52mm
Steering Stops: Does not match stock, welding required if wanted
Recommended Fork: 636
Difficulty to Find: Low
-Cannot use 05+ as the steering stem is .5" too short (7" vs. the 7.5" required)

ZX10R
Average Price: $40
Usable Years: 04-10
Lower Clamp Diameter: 54mm
Steering Stops: Does not match stock, welding required if wanted
Recommended Fork: ZX10R
Difficulty to Find: Medium-Low
-Steering stem must be pressed out and a 650's stem pressed in to fit

Forks:
These are one of the two main points in doing a fork swap: much better suspension performance can be achieved with newer forks. For the upside-down forks you will be switching two, there are two main parts of the forks- an upper main housing that contains a spring and damping components, along with a bottom tube that moves up and down the main housing, and also has brake caliper mounts and holes to attach to the wheel axle. There are two forks needed- one that fits into the left triple clamp holes, and one for the right.

636
Average Price: $175
Usable Years: 03-08
Upper Clamp Area Diameter: 50mm
Lower Clamp Area Diameter: 52mm
Wheel: Requires new wheel- accepts a 25mm axle vs. the 20mm axle the 650's stock wheel uses
Recommended Upper Triple Clamps: All
Recommended Upper Triple Clamps: Z1000, Versys 650, 636
-(03-04)Requires 20mm spacers for calipers to reuse the stock 650 rotor (Forks designed for 280mm rotors vs. 300mm rotor on stock Ninja 650)
-(04-08)No spacers for calipers required

ZX10R
Average Price: $200
Usable Years: 04-10
Upper Clamp Area Diameter: 50mm
Lower Clamp Area Diameter: 54mm
Wheel: (04-05) Does not require new wheel- accepts a 20mm axle
Wheel: (06-10) Requires new wheel- accepts a 25mm axle vs. the 20mm axle the 650's stock wheel uses
Recommended Upper Triple Clamps: All
Recommended Upper Triple Clamps: Versys 650, ZX10R
-Only useful if the 04-05 years are used so you don't need to buy a new wheel


Brake Calipers and Brake Pads:
These are the second main reason to do the fork swap: much better braking performance can be achieved with the right calipers. These are the things that connect to the bottom fork tube brake caliper brackets that contain pads which make contact with the brake rotor attached to the wheel when you pull the brake lever in, creating resistance and slowing the bike down. You will need a pair of brake calipers, one for each rotor.

Concourse, 636, ZX14R
Average Price: $75
Usable Years: 03-06
Brand Name: Tociko
Effectiveness: These are a good, cheap option for brakes on a budget

Concourse, 636, ZX14R
Average Price: $150
Usable Years: 07+
Brand Name: Nissin
Effectiveness: These seem to be the better option, offering much better braking performance over the Tocikos


Wheel, Wheel Axle and Spacers:
The wheel is attached in between the two forks via the wheel axle, a long metal rod. Spaces are used on either side of the wheel to transfer load to the correct part of the wheel bearings. Replacements to the stock wheel/wheel axle are usually needed due to different wheel bearing/axle sizes with the new forks, depending on the path you wish to take.

For 636 Forks
636
Average Price: $175
Usable Years: 03+
Required Axle: 636
Axle Diameter: 25mm
Required Spacers: 636
Required Wheel Bearings: 636
Bearing Size: 47mm OD x 25mm ID x 10mm Wide

Stock 650
Average Price: N/A
Usable Years: All
Required Axle: 636
Axle Diameter: 25mm
Required Spacers: 636
Required Wheel Bearings: 636
Bearing Size: 42mm OD x 20mm ID x 10mm Wide
-Wheel bearing seating area must be milled out to fit the larger 636 bearings


For 04-05 ZX10R Forks
Stock 650
Average Price: N/A
Usable Years: All
Required Axle: ZX10R
Axle Diameter: 20mm
Required Spacers: ZX10R
Required Wheel Bearings: 650
Bearing Size: 42mm OD x 20mm ID x 10mm Wide

Front Fender:
This is the piece of plastic that hovers over the wheel that keeps road debris from hitting the bike. Because you will be swapping forks, the things with the mounting points for the fender, you must get a new front fender that matches the forks you are swapping with.

For 636 Forks
636
Average Price: $50
Usable Years: Must use 03-04 fender with 03-04 forks
Usable Years: Must use 05-08 fender with 05-08 forks

For 03-04 ZX10R Forks
636
Average Price: $50
Usable Years: 05-08

ZX10R
Average Price: $50
Usable Years: 04-10

Master Cylinder:
This is the thing that translates your pull of the brake lever to increasing pressure within the brake lines that causes the brake pads to press against the brake rotor. It is mounted to the handlebar and brake lever, and contains a piston that gets pushed with the lever and a reservoir that holds extra brake fluid. Because you will be using higher performing brake calipers, it is a good idea to use a new master cylinder that can force more pressure into the brake lines faster.

Stock
The stock master cylinder can be used effectively, however a performance decrease most likely occurs

Non-Stock
To get optimal braking performance, a radial-type master cylinder is required
Examples: CBR1000RR, R1
Average Price: $75-$100
-Make sure you have the master cylinder, reservoir and mounting bracket, and lever

Handlebars/Clip-Ons:
These are the things that mount to the upper triple clamp than you put your hands on. In some instances and swap cases, the new upper triple clamp will require a different setup than the stock handlebar, as the attachment method differs from the 650.

Stock
-If you have the Z1000 upper triple clamp and a 12-15 650, the stock handlebars and risers can be swapped over to the new uppers.
-This lets you keep the rubber mounted handlebars
-This also means that any aftermarket bars that use the 650 risers can be used (E.X. Sportbars)

Non-Stock Handlebars
Example: Protaper Trials Mid Rise
-If stock handlebars will not work, buying handlebars that match the upper triple will work if mounts are available
-This options means your handlebars will not be rubber mounted (Unlike 12-15 650s)
-636 and ZX10R upper triples will only work with clip-ons and do not have handlebar mounts

Clip-Ons
Example: Woodcraft
Example: Danmoto
Example: Apex
-This options means your handlebars will not be rubber mounted (Unlike 12-15 650s)
-For 12-15 650s, a clip-on riser must be used (Danmoto and Apex risers both work)

Brake Rotors:
These are the metal rings that bolt onto the wheel that the brake pads make contact with to slow the bike down. Some swap cases may or may not require to use new rotors, as the rotor diameter/mounting holes may be different than the other component allow.

Stock 650
There is never really a practical reason to use other rotors

Other Parts/Hardware:

-Caliper Mounting Bolts
-Steering Stem Bearings
-Banjo Bolts/Banjo Bolt Washers
-Brake Lines
-Rotor Mounting Bolts

Questions and Answers:
This is where I will link any questions asked regarding the swap from this thread, this forum, and even other forums. I will also link the corresponding answer(s)

Tips/Other Information
***This is where any other information is added, such as things to look out for, torque specs, techniques and DIY tools used, etc

-Kojiiro's DIY Fork Compressor::: RiderForums: "Starting the Fork Swap" --- Post 7

-You will need to hang your bike from the ceiling, or use a stand like the Abba superbike stand. Because you will be removing the triples, a standard front stand will not work.
----A front triple tree stand is helpful, however, as taking off the upper triple clamp can be difficult if the rope holding the bike from the ceiling is putting pressure on it.

-If you will be replacing the wheel, try to do this when you are needing to replace the tire anyway. Less work down the road. :)

-Since you are replacing the brakes, you must drain all brake fluid from the old system, then fill up the new system with new fluid. The calipers may take a while to fill up, so once the fluid slows down a bit, walk away for a few minutes and see is the level has changed.

-With a radial master cylinder, if you choose to go that route, you may have some trouble mounting it and having it interfere with the throttle cables. Refer to this post: MC Issues


Swap Guides:
This is where I will link any guides made for the swap, which may end up extending to other bikes as well

-Kojiiro's Fork Swap Guide::: RiderForums: "Starting the Fork Swap" --- Posts 1-3
-----Post 1-2 is precursor stuff, post 3 is the guide. Good for a step-by-step process of what he did for the swap.

-DJRussell's Fork Swap Guide::: RiderForums: "636 Fork Swap Completed" --- Post 1
-----He lists the main components he bought and a reasoning behind it

Resources:
This is where I will post links to threads and sites that I or others believe contains useful information regarding the swap

Fork Swap Threads
KawiForums: "636 Fork Swap"
-----Great, long thread detailing out a lot of different setups and opinions
BRP 650 Forum: "636 Front End Swap"
-----Decent thread that has some basic information and questions- very short
Adventure Rider Forums: "Kawi 650 on a Budget: Roadie-Adventurer"
ZX10R Fork Swap Blog Series
WebDC: "Part 1: Fork Selection"
WebDC: "Part 2: Caliper Selection"
WebDC: "Part 3: Which Triple Tree?"
WebDC: "Part 4: Putting it all Together"
WebDC: "Part 5: Selecting the Headlight"

Informational/Servicing
YouTube: "Steering Head Bearings: How to Replace and Adjust"
-----Good video detailing steering bearing replacement, if you plan on doing so with your used triples
KZRider: "Upside Down Fork Rebuild: 2.0"
-----Good thread detailing replacing fork seals on your new inverted forks, as it is highly recommended when buying used forks
KawiForums: "How-To: Dismantle Inverted Forks"
-----Good thread detailing replacing fork seals on your new inverted forks, as it is highly recommended when buying used forks
YouTube: "How To: Replace Fork Seals - 03-04 Kawasaki Ninja ZX-6R"
-----Good video detailing replacing fork seals on your new inverted forks, as it is highly recommended when buying used forks
-----This video is even detailing the same forks as you will be buying if you choose the 636 fork route!

Parts
EBay
-----Good site for finding motorcycle parts
WERA Classifieds
-----Good site for finding motorcycle parts
Craigslist
-----Good site for finding local motorcycle parts

I think the fork swap is a really cool project that can suit many levels of technical abilities, and my efforts here are to bring all the knowledge regarding the project to more people to make it easier to dive into.http://www.kawiforums.com/how-tos-faqs/184673-how-dismantle-inverted-forks-pic-heavy.html
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Hi. Welcome onboard.

In 2012 Kawa did cosmetic and frame changes, but I believe the front end has stayed the same through all generations - so there is a good chance that it would fit. I read on another forum that a guy fitted 2004 ZX6R front forks to his 2012 model - which is basically the same as your '15.

Although, if you don't want to use clip-ons with that front end, you are going to have to fit up a different top triple tree, and from what I understand, it's not just a simple swap, there's a fair bit of work involved.
Thanks for the info! I'll try to get some measurements to confirm.

Just to share an update with you guys, I built the 15 I picked up a year and a half ago into a road race bike. I swapped in a 2005 ZX10R front end using the info from this thread which worked, but the issue I ran into was pressing the 650 steering stem into the ZX10 lower. The lower got bent in the process and is giving me problems (probably also aggravated by a recent crash 😂) so I'm looking into other options. I know a guy selling a ZX6R front end from his 08, hence my original question.




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Thanks for the info! I'll try to get some measurements to confirm.

Just to share an update with you guys, I built the 15 I picked up a year and a half ago into a road race bike. I swapped in a 2005 ZX10R front end using the info from this thread which worked, but the issue I ran into was pressing the 650 steering stem into the ZX10 lower. The lower got bent in the process and is giving me problems (probably also aggravated by a recent crash 😂) so I'm looking into other options. I know a guy selling a ZX6R front end from his 08, hence my original question.
Since you have the ZX10 front end, why not just buy another lower and get a good machine shop to press the stem into it like before. Might be a hell of a lot cheaper than a complete new front end swap.
Since you have the ZX10 front end, why not just buy another lower and get a good machine shop to press the stem into it like before. Might be a hell of a lot cheaper than a complete new front end swap.
Yeah I will probably do this eventually and keep the ZX10 front end as a backup. I have a fork issue that needs repair also, and besides I'm getting a really good deal on the ZX6 one. Never hurts to have spares when you're racing :ROFLMAO:
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2008/10 zx10 triple trees are the right size for the 04 zx10 forks and also bolt right up to a 650. thats how i got mine on -

If you have a zx6 front end though...
2007/08 zx10 triple trees are the right size for the 04 zx10 forks and also bolt right up to a 650. thats how i got mine on -

If you have a zx6 front end though...
Does the 07/08 zx10 steering stem fit as well? Or do you still have to press in the 650 stem?

The 650 stem in a 05 zx10 lower is a half inch too short, I had to get it pressed out to fit which means the bottom of the stem isn't flush with the bottom of the hole in the lower. I think that might have created a weak point and could be another reason why it got tweaked.

But yeah I know one of the MotoAmerica Twins Cup riders who has a complete zx6 front end he's getting rid of at a good price so I'm going to go with that and keep the zx10 front end as a backup.
Yes the 2008-10 zx10 triple tree is a bolt on fit for a er650
It holds 50/54 forks
No mess, no fuss
03/04 zx10 forks use a similar axle to the er650 and you can use the same front wheel
All other zx10 forks use a different wheel. You can check the bearing numbers to verify

The zx6 front end is typically 50/52 mm and uses a different axle size so uses a different wheel to the er650

*** This post has been updated ***
I had originally said that the 07/08 ZX10r triple tree is a stright fit for a 650; This is incorrect you need an 2008-10 ZX10r triple
Yes the 07/08 zx10 triple tree is a bolt on fit for a er650
It holds 50/54 forks
No mess, no fuss
03/04 zx10 forks use a similar axle to the er650 and you can use the same front wheel
All other zx10 forks use a different wheel. You can check the bearing numbers to verify

The zx6 front end is typically 50/52 mm and uses a different axle size so uses a different wheel to the er650
Gotcha, good to know on the 07-08 zx10 triple. I'll keep an eye out for one.

Still going to get the zx6 front end though. It's a complete 05 front end with upgraded forks (springs and valve kit) and includes a wheel.
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Yeah the zx6 kit sounds like what you need, especially with a valve kit and wheel
Gotcha, good to know on the 07-08 zx10 triple. I'll keep an eye out for one.

Still going to get the zx6 front end though. It's a complete 05 front end with upgraded forks (springs and valve kit) and includes a wheel.
Correction you need the 2008-10 zx10r triple
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Got the ZX6R front end on the bike. It's actually an 05-06 front end with 03-04 lower triple, so it bolted right on with no modification. Only catch was that I found one of the brake rotors was bent. Thankfully I was able to swap in the 650 rotors, which bolted right onto the ZX6R wheel. Excited to let it rip at the track this weekend 😁
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Great to hear it worked out. Note that you have a hydraulic clutch ?? Would you share any details you might have of that ? Did you do the conversion yourself ?
Great to hear it worked out. Note that you have a hydraulic clutch ?? Would you share any details you might have of that ? Did you do the conversion yourself ?
That's actually a hand lever for the rear brake I got from a stunt bike shop (tacticalmindz). I can't use my feet so I need hand controls for the rear brake and shifter. The normal clutch lever is below the rear brake lever (see 1st pic).
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That's actually a hand lever for the rear brake I got from a stunt bike shop (tacticalmindz). I can't use my feet so I need hand controls for the rear brake and shifter. The normal clutch lever is below the rear brake lever (see 1st pic).
i see… I don’t know how Id go with that. My levels of coordination aren’t that great.How do you manage mid corner upshifts? I reckon your a bit better rider than I am …
i see… I don’t know how Id go with that. My levels of coordination aren’t that great.How do you manage mid corner upshifts? I reckon your a bit better rider than I am …
I try to avoid them but a quick chop of the throttle will allow me to upshift quickly without the clutch. Hoping to find a suitable quick shifter to make the process even easier.
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I try to avoid them but a quick chop of the throttle will allow me to upshift quickly without the clutch. Hoping to find a suitable quick shifter to make the process even easier.
Only ones ive seen are with Power commanders or similar. Our bikes have only very basic ECUs and never had it from factory.
Having some promblems here. Any advice that what is wrong?

I have:
  • 11 ER6n.
  • Stock Er6n wheel.
  • 04 ZX10R fork.
  • Milled Versys lower triple.
  • Z1000 upper triple.
  • 09 ZX6R Nissin calipers.

I though that these would be direct bolt on with these parts, but however brake calipers won't fit the rotors. Using Er6n spacers and ZX10R axle. With ZX10r spacers there is almost 10mm gap on axle. Could these be wrong brake calipers and not the 09 ZX6R ones which they were sold for me?
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04 zx10 forks you need o4 zx10 spacers
I’m surprised there’s a 10mm gap.
when you milled the triples what’s the distance between the two staunchen centres. That’s what seems to be out for some reason.
All of the callipers are all the same offset. Radial offset can be set with spacers
Lateral offset you’ll need to space the disc

somethings not right here but I can’t see what
Zx10 spacers are about 13mm from memory
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