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Chuck78 wrote: 10:01 pm Apr 09 2026The aluminum steering stems are definitely a bit lighter, and every little bit counts if you're trying to save weight everywhere, but one should take note there very thick, so taking 2 mm off of the diameter, 1 mm wall thickness, is not any significant amount to be worried about structurally.

Yes, I agreed they are lighter but by how much is the question? Is it actually significant enough to warrant dubious machining of an aluminum stem down? I don't think so. I strongly disagree with you that taking 1mm of wall thickness off an aluminum stem is not a significant amount. 1mm of wall thickness on a hollow aluminum (hell, even steel!) tube is very significant in a highly stressed part that is already made to be the lightest the engineers felt was safe. No offense but I'm going to trust the guys with the engineering degrees over that random guy who "made it work" on his bike. He's not going to be around if and when it fails on someone and gets them hurt or killed. That's just my .02 on that particular mod.

If the aluminum stem is really worth having, the only current, and safe, option is the cheap Chinese conversion bearing. At least if the bearings fail the front end will at least stay on the bike.

Chuck78 wrote: 10:01 pm Apr 09 2026The bigger issue beyond that is the labor involved to press out two stems, knurl and press it back in, and then machine a bushing to mate to the top triple. Why take out a perfectly good aluminum stem that's usable with the bearings available nowadays, to do all that labor to get something slightly heavier that requires some makeshift modifications to make it a press fit? I know no one's ever had a failure reported from the knurling, but still, it's less than my standards to do so when better alternatives exist.

Labor...that's kind of ironic when talking about turning down a stem don't ya think? It's the same process as making a spacer. That takes a lathe and, for the most part, only a machine shop will have that particular piece of equipment and I highly doubt they would do it if they knew what it was for (liability).

Yes, doing a stem swap takes a few more steps but, if you have ever done one, you know it's very easy to do. Any small press that can physically hold the stems length+lower triple thickness can do it and hand knurling tools are available on Amazon. This allows you to continue to use stock sized bearings that are easy to find and can be found in different quality levels.

The KDX steel stem knurling has been proven to be safe and reliable on lots of KDX's over the years. I've had two done that way, one with over 800 hours since the swap, and nothing has moved in any way.

IMO, there are really only the two options, KDX stem swap or the conversion bearing used with aluminum stem. Both will work and not risk the safety of the rider. The conversion bearing is the cheapest option by far.

What's the opinion on the e series upside down forks? Good or bad?

E-series USD forks are better than the conventionals but parts are not the easiest to find and still lack rebound control. I would rather have the later KLX USD forks because at least parts are easier found.

ss109 wrote: 02:37 am Apr 18 2026 E-series USD forks are better than the conventionals but parts are not the easiest to find and still lack rebound control. I would rather have the later KLX USD forks because at least parts are easier found.

Okay ill cross that off my list of forks to look for. I have found a set of 96 rm forks for sale, but they are quite a drive away, so my hunt continues.

Nighthawk016 wrote: 08:47 am Apr 18 2026

ss109 wrote: 02:37 am Apr 18 2026 E-series USD forks are better than the conventionals but parts are not the easiest to find and still lack rebound control. I would rather have the later KLX USD forks because at least parts are easier found.

Okay ill cross that off my list of forks to look for. I have found a set of 96 rm forks for sale, but they are quite a drive away, so my hunt continues.

The '98 RM forks are the best of the 3 years of Twin Chamber conventionals, & have more readily available bushings shared with the DRZ400SM forks. The 02-24 DRZ400/400E/400S forks are also fantastic after a revalving, and while lacking a mid-valve, someone I believe on ThumperTalk.com or ADV Rider had actually figured out what parts were needed to convert them to a mid-valve setup. You'll want the 96-98 RM triples though if using the DRZ400 49mm open chamber conventionals (better offset, otherwise identical), & will need to swap a CRF250 or later CR250 1997+ steering stem after milling the Suzuki lower triple raised step lower bearing seat area to look like any other triple clamp (prior to pressing in the CR250R stem).

The 41mm E-Series forks are also really only good for very lightweight riders due to the 41mm tubes, or else very casual 175-190lbs riders as that's the only spring rate available for the aftermarket if I recall correctly.

99-08 KX 125 250 2-stroke and 04-05 KawaZuki KX250F / 04-06 KawaZuki RM-Z 250 forks also, as well as 04 YZ125/250 forks in YZ250 2-stroke triples, those are my top picks for KYB 46/48mm open chamber inverted forks.

I've got some 97-04 KX500 forks and triples that are a direct bolt on as well which I'd most likely sell with a bunch of rebuild and upgrade parts and 2 specialty KYB tools except for the fork seal driver I'm keeping. Race Tech Gold Valves also. Direct bolt on, same steering stem as the KDX/KLX. I've got a lot of cash wrapped up in them but probably won't be running them now that I have so many Showa Twin Chamber '98 RM forks and '19-'25+ KX450 Showa Twin Chamber inverted forks and KLX300 forks...

The 1993 - 1994 KDX200 (USA) forks have 41 mm inner tubes. The 1991 - 1994 KDX250 and 1994 - 2007 KLX250R / KLX300R / KLX650R and such forks have 43 mm inner tubes. They are about the same inside, so go with the bigger tubes if you are just "out shopping". Also, the stock spring rate on the 93/94 KDX200 forks are a whopping 0.30 !!

I do love my sweet looking stock forks on the 94 though. :-) Correct rate springs and Race Tech Gold Valves helped a lot.

Chuck78 wrote: 02:41 pm Apr 18 2026

Nighthawk016 wrote: 08:47 am Apr 18 2026

ss109 wrote: 02:37 am Apr 18 2026 E-series USD forks are better than the conventionals but parts are not the easiest to find and still lack rebound control. I would rather have the later KLX USD forks because at least parts are easier found.

Okay ill cross that off my list of forks to look for. I have found a set of 96 rm forks for sale, but they are quite a drive away, so my hunt continues.

The '98 RM forks are the best of the 3 years of Twin Chamber conventionals, & have more readily available bushings shared with the DRZ400SM forks. The 02-24 DRZ400/400E/400S forks are also fantastic after a revalving, and while lacking a mid-valve, someone I believe on ThumperTalk.com or ADV Rider had actually figured out what parts were needed to convert them to a mid-valve setup. You'll want the 96-98 RM triples though if using the DRZ400 49mm open chamber conventionals (better offset, otherwise identical), & will need to swap a CRF250 or later CR250 1997+ steering stem after milling the Suzuki lower triple raised step lower bearing seat area to look like any other triple clamp (prior to pressing in the CR250R stem).

The 41mm E-Series forks are also really only good for very lightweight riders due to the 41mm tubes, or else very casual 175-190lbs riders as that's the only spring rate available for the aftermarket if I recall correctly.

99-08 KX 125 250 2-stroke and 04-05 KawaZuki KX250F / 04-06 KawaZuki RM-Z 250 forks also, as well as 04 YZ125/250 forks in YZ250 2-stroke triples, those are my top picks for KYB 46/48mm open chamber inverted forks.

I've got some 97-04 KX500 forks and triples that are a direct bolt on as well which I'd most likely sell with a bunch of rebuild and upgrade parts and 2 specialty KYB tools except for the fork seal driver I'm keeping. Race Tech Gold Valves also. Direct bolt on, same steering stem as the KDX/KLX. I've got a lot of cash wrapped up in them but probably won't be running them now that I have so many Showa Twin Chamber '98 RM forks and '19-'25+ KX450 Showa Twin Chamber inverted forks and KLX300 forks...

I can tell you have a lot of time invested in suspension mods. Finding 98 specific forks will be a hassle, but ill keep my eyes open, I have a stock set of 96 triple clamps in my shed, so if I do that swap I wont need to hunt. So I'd need forks, front wheel and brakes. Then the mods to make them fit properly.

KDXGarage wrote: 12:16 pm Apr 20 2026 The 1993 - 1994 KDX200 (USA) forks have 41 mm inner tubes. The 1991 - 1994 KDX250 and 1994 - 2007 KLX250R / KLX300R / KLX650R and such forks have 43 mm inner tubes. They are about the same inside, so go with the bigger tubes if you are just "out shopping". Also, the stock spring rate on the 93/94 KDX200 forks are a whopping 0.30 !!

I do love my sweet looking stock forks on the 94 though. :-) Correct rate springs and Race Tech Gold Valves helped a lot.

Based on this info alone, ill avoid the 41mm forks.

1996 KX clamps will have a large stem hole.

KDXGarage wrote: 12:44 am Apr 23 2026 1996 KX clamps will have a large stem hole.

I meant 96 rm250, sorry if that wasn't clear!