Buying a 2018 sx250 with 4cs Forks vs aer 48?? Help

moto_marcus
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moto_marcus
So I’m looking at purchasing a 2018 sx 250 with 8 hrs on it but the guy selling it swapped out the aer 48 that came on the bike with the 4cs fork. He then sold his other bike with the aer 48 and is just left with this bike as is.

Is this a big deal? Being that I mainly ride single track I think (once re valved) that I wouldn’t mind the 4cs. Maybe I’m wrong here and the 4cs is as bad as everyone makes it sound, or the aer is as great as everyone says.

I’m also concerned about the re sale value of the bike. Will people quickly glance over this when I try to re sell it once they see this fork on the bike?
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yz133rider
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yz133rider 8/21/2019 7:46am
8/21/2019 7:46am
Is it discounted? If so consider getting del sagio inserts or ohlins inserts as opposed to revalve.
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theycallmeebryan 8/21/2019 7:46am
8/21/2019 7:46am
I call 4CS forks the "4 crap shitty" forks. That said, there are many aftermarket options out there that can turn the fork into something good. N2Dirt and Kreft are two good companies that do work with that fork.

In terms of resale, any potential buyer that knows about dirtbike components would probably shy away from your bike if it has 4CS forks on it. The AER48 are much better forks and are more versatile in my opinion.
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Lineman25
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Lineman25 8/21/2019 7:48am
8/21/2019 7:48am
Not a big moto rider but I don't care for the aer on my 2019 300 xc. No comparison to the kybs on the Yamaha I had prior. Although I have never ridden a bike with 4cs forks so can't give input there.
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RCMXracing
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RCMXracing 8/21/2019 7:48am
8/21/2019 7:48am
They might be ok for single track. Death for moto.

A very inexpensive mod, Base Compression Valves, so compression is now adjusted on the bottom and the top is rebound. Go from sad to happy and no death.

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Kennyfreemoney 8/21/2019 7:52am
8/21/2019 7:52am
Don't buy it. Not because of the forks, but because its a 250sx. Get an XC or XC-w if you ride single track. An XC will still be a great bike on the track, but it will be a WAY better bike in the woods
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Hammer 663s
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Hammer 663s 8/21/2019 7:53am
8/21/2019 7:53am
Lucky System. YW.
JWACK
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JWACK 8/21/2019 8:03am
8/21/2019 8:03am
4cs forks were the worst forks I have had in my 30 years of riding.
I would pass unless it’s cheap enough deal to do a Kyb conversion right away.
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moto_marcus
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moto_marcus 8/21/2019 8:45am
8/21/2019 8:45am
Kennyfreemoney wrote:
Don't buy it. Not because of the forks, but because its a 250sx. Get an XC or XC-w if you ride single track. An XC will...
Don't buy it. Not because of the forks, but because its a 250sx. Get an XC or XC-w if you ride single track. An XC will still be a great bike on the track, but it will be a WAY better bike in the woods
Well I also ride a bit of track, dune, free ride, etc. but I do agree with you. It was a good deal so that did not really bother me. Just wondering if the deal was good enough to put up with 4cs forks as I have not ever owned a bike with them. From everything I’ve heard, and read I will probably pull out of the deal.
RCMXracing
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RCMXracing 8/21/2019 11:27am
8/21/2019 11:27am
I think an inexpensive BCV modded 4CS spring fork is solid and good for an all around dirt bike guy and maybe better than AER because no fiddling. It’s good! I went from “I’m gonna die” to a big F’ng smile after the mod.

If you are moto specific the AER is better but takes checking the PSI every time you ride, sometimes mid-day.
Motofinne
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Motofinne 8/21/2019 1:44pm
8/21/2019 1:44pm Edited Date/Time 8/21/2019 1:48pm
AER is a way, way better fork than the 4CS. It is actually better than multiple spring forks.

The 4CS is horrible, just like the Showa SFF spring fork (ie, not all spring forks are good). But you could always swap the internals for a set of Öhlins TTX cartridge kit for a relatively small investment. Try to push the price down as much as possible because of the forks and get the TTX cartridge kit (springs on both sides, not only one is the important factor in fork conversions in my opinion).
PTshox
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PTshox 8/21/2019 2:09pm
8/21/2019 2:09pm
If you can get it cheep enough you can put a MXTech lucky system in those for about a 1,000 dollars. It's a bolt on mod.

I myself modded my 4cs with some parts from DaveJ at Smart Performance. Work fine after some tuning. But stock... they were scary!
m21racing
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m21racing 8/21/2019 2:22pm
8/21/2019 2:22pm
Aer are longer than 4cs. I'd be worried about the effect on the chassis, as KTMs are very sensitive to any changes. Pass on it. Find another bike with aer, put dal saggio in it. When you sell, take dal saggio cartridges out, aer back. Selling dal saggio used will have a better return than a kyb conversion.
Motohead279
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Motohead279 8/21/2019 2:31pm
8/21/2019 2:31pm
Like others have said the 4CS forks were the worst forks ever, I have no idea how they ever made it into production. They have almost killed me several times before I switched to cone valves.

You can do the conversion on them and make them pretty decent.
stone881
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stone881 8/22/2019 6:39am
8/22/2019 6:39am
I love mine with KYB internals, the catch is that you need to find the KYB's.
AJ565
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AJ565 8/22/2019 6:52am
8/22/2019 6:52am
If you can get it cheap enough because of the forks there is always cone valves for sale on here and they are amazing on that chassis.
sam hain
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sam hain 8/22/2019 7:33am
8/22/2019 7:33am Edited Date/Time 8/22/2019 7:34am
AJ565 wrote:
If you can get it cheap enough because of the forks there is always cone valves for sale on here and they are amazing on that...
If you can get it cheap enough because of the forks there is always cone valves for sale on here and they are amazing on that chassis.
I've got a set of cone valves I'd sell. Getting them back from powerband tomorrow after a revalve and oil change.
They were bought new last year from powerband, have about 20hrs on them.
racerhansen
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racerhansen 8/25/2019 8:17am
8/25/2019 8:17am
THe 4CS is probably the worst fork to hit the market in the last 10-15 years
GeorgiePorgie 8/25/2019 8:33am
8/25/2019 8:33am
Just puked In my mouth. why would anyone bastardize a motorcycle like thatby putting 4cs on it? Prolly cuz he couldn’t sell his prior bike with that garbage.
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