The final word on SFF spring conversions? Please advise (KTM/GG/HUS)

soggy
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soggy 10/17/2022 1:48pm
10/17/2022 1:48pm
That’s an air fork. Dampening on one side, air spring on the other.
lumpy790
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lumpy790 10/17/2022 2:52pm
10/17/2022 2:52pm
soggy wrote:
That’s an air fork. Dampening on one side, air spring on the other.
posted this in the wrong thread and moved it here where it should have been……

Correct spring in one side and air in the other. old set up sticker sticker on fork says 20+ air inflation.

Last time I had air forks was in the 1970’s lol


soggy
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soggy 10/17/2022 3:05pm
10/17/2022 3:05pm
soggy wrote:
That’s an air fork. Dampening on one side, air spring on the other.
lumpy790 wrote:
posted this in the wrong thread and moved it here where it should have been…… Correct spring in one side and air in the other. old...
posted this in the wrong thread and moved it here where it should have been……

Correct spring in one side and air in the other. old set up sticker sticker on fork says 20+ air inflation.

Last time I had air forks was in the 1970’s lol


That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s using a race tech conversion. They do sell a kit that uses the stock cap so people can get away with running a spring conversion in the stock class.
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paddyB745
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paddyB745 10/17/2022 3:22pm
10/17/2022 3:22pm
lumpy790 wrote:
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash...
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash course on it.

Anyone know what brand it may be?

Shock has a 54 and I need a 48 and fork has a .98k spring and I think its set up for a heavier rider.



There are a few kits that run a Schrader valve on their spring conversions so you can fine tune with a little air. Pr2 and pro circuit are the ones I can think of off the top of my head

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soggy
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soggy 10/17/2022 3:27pm
10/17/2022 3:27pm
lumpy790 wrote:
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash...
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash course on it.

Anyone know what brand it may be?

Shock has a 54 and I need a 48 and fork has a .98k spring and I think its set up for a heavier rider.



paddyB745 wrote:
There are a few kits that run a Schrader valve on their spring conversions so you can fine tune with a little air. Pr2 and pro...
There are a few kits that run a Schrader valve on their spring conversions so you can fine tune with a little air. Pr2 and pro circuit are the ones I can think of off the top of my head
I wonder if they use the stock fork cap still?
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R VanKamp77
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R VanKamp77 10/17/2022 4:28pm
10/17/2022 4:28pm
Being that it’s used I would totally take this opportunity to change the oil and inspect that. Show us what’s inside!
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lumpy790
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lumpy790 10/17/2022 4:42pm
10/17/2022 4:42pm
soggy wrote:
That’s an air fork. Dampening on one side, air spring on the other.
lumpy790 wrote:
posted this in the wrong thread and moved it here where it should have been…… Correct spring in one side and air in the other. old...
posted this in the wrong thread and moved it here where it should have been……

Correct spring in one side and air in the other. old set up sticker sticker on fork says 20+ air inflation.

Last time I had air forks was in the 1970’s lol


soggy wrote:
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s...
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s using a race tech conversion. They do sell a kit that uses the stock cap so people can get away with running a spring conversion in the stock class.
Previous owner said it was a single spring side that both Pro Circuit and Precision Concepts sold.

soggy
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soggy 10/17/2022 4:47pm
10/17/2022 4:47pm
lumpy790 wrote:
posted this in the wrong thread and moved it here where it should have been…… Correct spring in one side and air in the other. old...
posted this in the wrong thread and moved it here where it should have been……

Correct spring in one side and air in the other. old set up sticker sticker on fork says 20+ air inflation.

Last time I had air forks was in the 1970’s lol


soggy wrote:
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s...
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s using a race tech conversion. They do sell a kit that uses the stock cap so people can get away with running a spring conversion in the stock class.
lumpy790 wrote:
Previous owner said it was a single spring side that both Pro Circuit and Precision Concepts sold.

Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
1
Bruce372
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Bruce372 10/17/2022 5:27pm
10/17/2022 5:27pm
lumpy790 wrote:
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash...
OK guys I bought a new to me Husky this weekend and it has a spring kit on one side so I am getting a crash course on it.

Anyone know what brand it may be?

Shock has a 54 and I need a 48 and fork has a .98k spring and I think its set up for a heavier rider.



54 spring should be good for 230lbs plus rider

That fork convo is definitely not stock
lumpy790
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lumpy790 10/17/2022 6:42pm
10/17/2022 6:42pm
soggy wrote:
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s...
That doesn’t make any sense. These are separate function forks. Did the PO race it in any LL qualifiers or at the ranch? It’s possible it’s using a race tech conversion. They do sell a kit that uses the stock cap so people can get away with running a spring conversion in the stock class.
lumpy790 wrote:
Previous owner said it was a single spring side that both Pro Circuit and Precision Concepts sold.

soggy wrote:
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech...
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
Bruce372
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Bruce372 10/17/2022 7:49pm
10/17/2022 7:49pm
lumpy790 wrote:
Previous owner said it was a single spring side that both Pro Circuit and Precision Concepts sold.

soggy wrote:
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech...
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
lumpy790 wrote:
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy...
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
Measure the spring preload. You might be ok, especially once you've set the sag at 105mm with gear on.
kopfjaeger
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kopfjaeger 10/18/2022 7:21pm
10/18/2022 7:21pm
Disregard everything I have previously said in this thread!! I thought the OP had a 2023 KTM!! The GG is the same as the previous year, 22 and 21 ktm. 💀
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Gravel
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Gravel 10/18/2022 7:46pm
10/18/2022 7:46pm Edited Date/Time 10/18/2022 7:50pm
lumpy790 wrote:
Previous owner said it was a single spring side that both Pro Circuit and Precision Concepts sold.

soggy wrote:
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech...
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
lumpy790 wrote:
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy...
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try a 5.2 but I’m not sure it’d be any better. I think a 4.8 would be too soft. .52s in my fork, they’re pretty good too, I use the full stroke occasionally but normally have 10-20mm left unused after a ride.
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Bruce372
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Bruce372 10/18/2022 9:22pm
10/18/2022 9:22pm
soggy wrote:
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech...
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
lumpy790 wrote:
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy...
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
Gravel wrote:
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try...
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try a 5.2 but I’m not sure it’d be any better. I think a 4.8 would be too soft. .52s in my fork, they’re pretty good too, I use the full stroke occasionally but normally have 10-20mm left unused after a ride.
I'd stick with the 54, imo really helped my setup rounding up springs and not down.
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lumpy790
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lumpy790 10/19/2022 1:49pm
10/19/2022 1:49pm
soggy wrote:
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech...
Gotcha. Looks like it must be this kit. https://www.procircuit.com/air-to-spring-conversion-kit-wp-48-aer.html That’s a pretty stiff fork. I’m 180ish with gear running a .92 spring on my race tech sff conversion.
lumpy790 wrote:
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy...
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
Gravel wrote:
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try...
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try a 5.2 but I’m not sure it’d be any better. I think a 4.8 would be too soft. .52s in my fork, they’re pretty good too, I use the full stroke occasionally but normally have 10-20mm left unused after a ride.
2018 FC450 Rockstar so its the next platform from yours.

Race Tech does not show the 2018 Rockstar but going by the 2019 for my specs it should have a 5.0 and the 5.4 is 2 steps stiffer.
Bruce372
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Bruce372 10/19/2022 5:03pm
10/19/2022 5:03pm
lumpy790 wrote:
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy...
I’m 200 and shock has a 54 on it and going from the manual I need a 48 so guessing the forks are setup pretty heavy too.
Gravel wrote:
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try...
What year Husky? I’m 205, on a 2018 KTM 450xcf chassis, so maybe the same linkage, and a 5.4 is pretty close, I’d like to try a 5.2 but I’m not sure it’d be any better. I think a 4.8 would be too soft. .52s in my fork, they’re pretty good too, I use the full stroke occasionally but normally have 10-20mm left unused after a ride.
lumpy790 wrote:
2018 FC450 Rockstar so its the next platform from yours. Race Tech does not show the 2018 Rockstar but going by the 2019 for my specs...
2018 FC450 Rockstar so its the next platform from yours.

Race Tech does not show the 2018 Rockstar but going by the 2019 for my specs it should have a 5.0 and the 5.4 is 2 steps stiffer.
Measure your spring preload before buying a new spring
121x
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121x 10/21/2022 11:50am
10/21/2022 11:50am Edited Date/Time 4/16/2025 3:27am
@R VanKamp77 any update?
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R VanKamp77
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R VanKamp77 10/21/2022 12:01pm
10/21/2022 12:01pm
121x wrote:
@R VanKamp77 any update?
Sure do! I’m actually in the garage right now getting everything buttoned up. So I’ll have a ride report tomorrow. This thread is super long but if you’re struggling with your new 350, I think it’s worth the time to follow the evolution of issues I’ve been experiencing (perceiving?) and compare to your own experiences.

I’ll definitely post tomorrow too.
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121x
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121x 10/21/2022 12:05pm
10/21/2022 12:05pm Edited Date/Time 4/16/2025 3:27am
Awesome. Looking forward to it. I actually just finished reading through this thread a second time. So interested to hear your experiences once you have some seat time.

Hope it gets you closer to what you are shooting for!
NSP139
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NSP139 10/24/2022 8:17pm
10/24/2022 8:17pm
Any update?
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soggy
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soggy 10/24/2022 9:20pm
10/24/2022 9:20pm
NSP139 wrote:
Any update?
If you read through this whole thread you need to take everything this guy says with a large heaping of salt. Reads like someone that has no idea how to set up a bike.
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soggy
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soggy 12/1/2022 8:07pm
12/1/2022 8:07pm

Wheres the update man we are all dying to know. 😂😂😂😂

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