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Yes. Length is close to stock AER length. I have a set of lucky fork cartridges in another fork and they are about 1/4” shorter. These are perfect length. I was going to take some measurements for you but time was limited. I will get a picture up of the fork length with the kyb cartridge installed.
Just FYI. I used this tool in 43mm on my Harley Low Rider St. I needed to remove the lugs to install an Ohlins cartridge kit and Titanium Nitride fork tubes. I did have to use a lot of heat from a propane torch to get them off. The OEM Harley forks are Showa. I was worried about the tool being from China, but it was surprisingly well made.
https://www.ebay.com/itm/186218801573?hash=item2b5b8169a5:g:OFoAAOSwHBJ…
I use something different in my shop but that tool is pretty close to what I have in mind to sell.
It's best to heat up the WP / KTM lugs too. It softens the thread locker that the factory installs them with and the aluminum lug expands more than the steel tube.
I have a set of 06 YZ250 forks, would those cartridges work with the kit in my 21 GG?
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I'm not sure about the oil lock "bottoming piston" on the 2006 and 2007 Yamaha SSS forks.
I haven't had my hands on a set of those first two years of cartridges, only the 2008 and later stuff.
The photos I've seen look like they use a different cartridge seal assembly and a different oil lock.
I believe they would install in the forks since the thread on the cartridge rods is the same, but I don't know if there would be interference between the oil lock parts in my kit and your cartridge.
If you want to check the diameter, measure the outside diameter of the bottoming piston on your cartridge seal head.
My kits are designed to work with 28mm and 29mm sizes without crashing or interference.
28mm pistons will measure about 27.8mm to 28mm outside diameter.
29mm pistons will measure about 28.8mm to 29mm outside diameter.
Measure your cartridges from the bottom of the flange on the caps down to the bottom of the gold Kashima coated rebound rods when they're fully extended. A measurement of about 925mm would work with my "Short KYB Cartridge" kits and a measurement of about 935mm would work with my "Long KYB Cartridge" kit. The kits add 24mm and 14mm respectively, bringing your total length from the bottom of the cap flange to the centerline of the axle to about 950mmm.
If you have some photos or measurements, I can help you confirm if your cartridges are compatible. You can post them here, or shoot me an e-mail. sales@dialedmfg.com
Did you measure from the top of cap, or top edge of tube?
Top of cap
With that in mind, the cap is approximately 8mm tall from the top surface to the bottom of the flange.
That would give you an actual fork measurement of about 948mm relative to the OE KTM/WP 950mm.
Thanks for sharing that measurement.
Do you have a way of calculating spring rates? I assume the race tech spring chart is slightly off because of bike weight/ergonomics?
It's actually pretty good, they have added kyb setup options, you can also do a gold valve setup to suit.
I've found that the spring rates cross over pretty well between Yamaha and a KTM chassis for most guys. (2019 - 2022)
I don't have any tuning experience on the latest generation of KTMs, but I can't imagine it is very far off.
I tend to think the Race Tech spring recommendations are a bit on the softer or more comfortable side, at least for valving from Yamaha 250F / 450F in a KTM four stroke chassis. They probably make up for that with valving in their Gold Valve kits. A good tuner can do a lot with hydraulics.
Here are some specific bikes and spring rate examples I can give you from helping out my friends:
Using the selection for a WP spring fork, Race Tech suggests 4.6N/mm (0.47kg/mm) springs for me at 160lbs if I choose the "A / Expert" skill level (I am 40+ A). I do tend to ride the front end aggressively. My body position is pretty far forward sometimes.
I am running a 0.49kg/mm spring in my GasGas MC350F and my fork is as soft as I can tolerate at 345cc of oil. I like the feel of the fork in most situations. It does bottom out, but I don't feel it. I have a 45N/mm spring in the rear and the high speed is cranked way in. The bike is balanced, but the rear also bottoms a lot. I will play with some valving on both ends and try the REP linkage system soon. I'd like to keep a softer setting on my 350F to deal with choppy conditions at the Washougal Amateur days event in the summer.
A 225lbs 40+ B/Intermediate friend had been testing a 350SX-F with my valving and my conversion for the past three years. We set him up with 0.51kg/mm springs and 325cc oil volume and he was very happy.
A comparison between a 250SX (two stroke) and my YZ250 (two stroke) that I did a few years ago showed that both felt very similar on similar fork spring rates. We had 0.48kg/mm fork springs in the KTM and 0.47kg/mm in my YZ.
Another friend who is about 6'1 and 190lbs age 38 C or Novice is riding 0.47kg/mm springs with 325cc oil volume in his 2022 KTM 150SX with my valving. He loves it and honestly I think that bike is super fun. (For comparison, I run a 0.45kg/mm spring with a 350cc oil volume in my 2011 YZ125).
My friend's 16 year old is becoming pretty fast. He is running a KTM 125SX with a 0.44kg/mm fork spring. He's about 145lbs and won the schoolboy class in the local series on that bike. We firmed up his stock shock with the clickers and high speed to balance the bike out and make it feel more like his '22 YZ250F.
Hopefully that helps and hopefully some other guys can give feedback too.
I like to be very honest about the fact that I'm a machinist / engineer, not an experienced suspension tuner.
I am using the stock 09 crf450r kayaba fork springs. They are .47 kg/mm and I weigh 180lbs without gear. Valving was fairly soft for a 450 and similar to a yz250 of the same year. I added a 28x.1 crossover and clamp is a 13mm. Oil height is 325cc. These are on a 22 250sx for mx and gp races. 450 I typically run a .50 or .52kg/mm fork spring. Shock for 250sx I run a 4.6kg/mm spring.
My buddy did the same …09-12 Honda 450
09-12 kx 450 , 2006 and up yz 125 and up
I just installed 2 of your kits and loved them. Amazing work. I currently have a set of aer lugs removed from installing an exact set. Do you need any lugs to maybe test fit or sell one of the kits for that version. I Live in maple valley so not to far from you.
I just heard this over the PA system at Daytona…
”CW to the Orange Courtesy Phone, please. CW to the Orange Courtesy Phone…”
https://www.vitalmx.com/forums/moto-related/sextons-secret-suspension-s…
Nice to hear that you're enjoying those conversions.
I actually keep one set of each type of lugs (AER-48 & XACT) on the work bench in my shop as reference parts and I have had a working design for the AER-48 fork lugs for a few years. I need to finalize one or two minor CNC program changes for production and get them on the machines. It has been a busy fall/winter in my shop, but I have a slot coming up after I finish some work for a wholesale customer. I'll do another run of the kits I currently sell for XACT forks, then produce the first run of those AER-48 kits.
At some point here soon, I'll have time to get back out riding/racing on weekends. If you see me, come say hello.
I'm often on my old YZ125 or YZ250 and now on the GasGas 350. All my bikes have #31 on them.
Pit Row
That sure looks like a KYB conversion to me.
Someone tell Roger and Ian about my conversion kits... They're a little more covert!
I'm bumping this due to seeing the DYI question come up on these forks/this type of application.
While I DO NOT have the outright disdain that some have for the AER fork...I do understand taht some folks just want their damn KYBs back...on their KTM or GasGas or Husky...so, here's another DIY solution for those that want to pursue the KYB Kit Solution.
? What was the DIY solution
has anyone messuered the 2011 yz250f cartrige yet ?
That's a short KYB cartridge with the large cap diameter and 24mm mid-valve.
The large cap needs the modification to fit through your upper clamp.
If you cover the shipping of your cartridge tubes, I will modify those caps for you.
2008 - 2013 YZ250F is a short cartridge.
2014+ YZ250F is a long cartridge.
2008 - 2011 YZ250F has the large cap diameter
2012+ has the small cap diameter that fits your Austrian top clamp with no modifications.
I don't have 2011 YZ250F cartridges here on the bench to measure, but I have two pair of short cartridges I can take a measurement from if you need numbers. Those are 2008 YZ250F and 2016 YZ250 two stroke.
If you are working on a Husqvarna with the shorter height, you can combine the short cartridges with a conversion kit for long KYB cartridges to end up at approximately 940mm fork length. If you are working on a KTM, GasGas or Rockstar Edition, you need the conversion kit for short KYB cartridges.
I don't have a measurement on it, but I'm running the '12 YZ 250F cartridge with @cwtoyota 's kit in my 22 Husky 350 (second year of the 10mm lower version), which tells me the 11 YZ 250F would also be the shorter version since there were minimal changes between '11 and '12. I believe they went to the longer one (which works on KTM and GG) in '14 with the new frame?
I couldn't be more happy with this kit BTW, I have about five hours on it riding multiple tracks and conditions. Front end is predictable, planted and compliant. I've felt more flow on the bike and have run more spontaneous long motos since I've installed it than I ever did before.
These photos detail the necessary cap modification.
It takes a few minutes to perform using a manual lathe.
are you shipping world wide ?
Yes, the free shipping is USA only but I have been shipping all over the world. It seems to range from $40 to $85 to most countries for a kit through the US Postal Service. FedEx and UPS are typically a little more.
The website will give you a few different shipping options with the cost in the shopping cart.
If the shipping seems unreasonable, send me an e-mail with your address and I'll double check the cost with the shipping companies.
Post a reply to: An easier KYB Spring Conversion for WP XACT 48mm forks.