To all Beta RX owners - I had been complaining about the rear suspension of my 2025 Beta 300 RX, with the rising rate being way too linear. You could have either good bottoming resistance or a somewhat plusher initial stroke, but you could not have both. The oem shock also had too much compression and rebound dampening, so the compromise setting was to turn out the clickers and set the preload as light as possible, but the light preload has a small negative effect on turn-in feel. Dirt Bike magazine had made the same comment about having to lighten shock pre-load.
The oem linkage knuckle is fairly short and I felt it wasn't putting enough leverage on the shock so I called around to see if someone would make a more progressive knuckle for the Beta. No luck, but about a month ago, Beta started selling a CNC knuckle it made and developed for their factory race team. It was just what the doctor ordered.
This new knuckle is much, much more progressive than the oem knuckle and without a revalve of the compression stacks, the bike would be almost unrideable even with LSC and HSC turned all the way out. The new knuckle also likes the rebound a few clicks softer. The revalve is a must for this knuckle as the clickers with the oem valving is not enough. Not essential, but a 0.5 to 1kg softer spring rate would also help bring things back in line. In the end, the knuckle allowed me to soften the initial stroke to get the plushness I was after and still have excellent bottoming resistance. It is a very dramatic difference.
According to the Beta suspension department manager, most of the team liked the stock length pull rod with the new knuckle, and only very tall riders liked a shorter pull rod.
The Beta 250, 300, 350 RX 2Ts and 450 RX 4T all use the same knuckle. If you ride MX, this new knuckle is an absolute must have, in my opinion. In the pic below, the oem knuckle is on the left and the new CNC factory knuckle is on the right.
Did you try the knuckle before a revalve?
If you were riding with compression clickers all the way out then you likely have springs that are too heavy.
Yes, I did.. almost unrideable with the clickers turned all the way out.
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You are totally not understanding the issue.
Seems like the spring is the issue?
You had almost no preload and compression all the way out, and too much rebound...............That would all be caused by having a spring that is too heavy for the rider.
Then you installed this knuckle, it still felt like crap, then you did a revalve and everything felt great.
Your independent variable is the revalve.
Your test didn't isolate the characteristics of the knuckle from the revalve, so we'll never know.
Did you replace the spring during the revalve?
Hi 3-stroke, I know you are trying to be helpful, but you are very much confounding the issue and trying to unsolve a problem already solved. You are also assuming I do not check my free sag to confirm my spring rate is appropriate for my weight. My free sag was 35mm with the oem knuckle. I weigh almost 200 pounds w/o gear and I have the oem 5.3kg spring on it. The spring rate is not too stiff. I did not start with minimal preload .. that was a last ditch effort to a little initial plushness after trying everything else. Also, too stiff of a spring is not going to cause the rebound dampening to be too heavy. On top of that, you did not catch that I had the clickers all the way out only for the test of the new knuckle (which is much more progressive) before the expected necessary revalve. So you have a number of points conflated here.
I did an initial revalve before I even tried the new knuckle, but it didn't help much and I was suspect of the rising rate of that oem knuckle from the start. I rode it once with the new knuckle and totally expected it to ride like shit, but needed to get a feel so I could inform the suspension tuner how much we needed to soften the compression valving, although we already had a hint from the Beta suspension department. Then we re-valved it again for the new knuckle... all which is expected and now it is great.
The process absolutely did isolate the effect of the knuckle itself... by riding with the knuckle (and no other changes) before the 2nd revalve which it obviously would need, all the time expecting it would ride like shit w/o another revalve.
Beta suspension and RG3 suspension were involved during this process, so no need to try to re-solve the issue.
This post is intended to help other Beta riders improve their bikes. Expert suspension tuners from 2 shops were involved and I think no need for us to confuse the issue further.
I'm happy for you that you got your bike to your liking.
Where we disagree is that the RX's have a problem with their linkage ratio. Im not saying they are perfect and I'm open to the possibility it could be better, but there would also be a trade off (and you're implying there is no tradeoff).
If you had a specific issue you were working on I'd be more inclined to listen, but the general not plush but poor bottoming is indicative poorly matched suspension.
Your appeal to authority has no influence on me. Seems naive to assume RG3 would nail the revalve on the first try, I doubt they see many RX's, this might have been their first? But you're liking their 2nd try better, influenced by your feedback, that's a story I'd buy.
The hyperbolic "this knuckle is an absolute must have" LOL. The knuckle isnt going to fix a poorly matched shock (like you confirmed).
Maybe you could test the current shock revalve that you like with OE knuckle vs New knuckle and then you'd have some finer points to tease out?
I hope you didnt have to sell a child to buy it, how cheap was it?
It looks like you are just trying to be contrarian for contrarianism's sake. Do you realize you are not even making sense?
It was US$350 from Beta.. only slightly more than what they charge for the oem knuckle.
Does it sound like this linkage ratio will make it onto production bikes in the future? I've been considering a beta for my next bike.
Glad for the feedback on the knuckle.
As you are well aware, suspension setting is a lot of personal preference, so no one setting or part will work for everyone. But with your explanation it helps to understand what the knuckle does if that's a feel someone isn't getting and wants.
I feel the stock knuckle is still probably pretty good for a majority of 450RX buyers that are a little older/slower or more multi use such as myself (use for everything, not just MX).
The knuckle and revalving from Bryce back at Beta is probably the hot ticket for full time MXers. Take advantage of the BYOB program and the guy that works with the knuckle on a daily basis. Curious to see if the knuckle is under the pro NHHA and GNCC bikes too.
I got very similar results in a slightly more expensive option with the MX Tech National shock. Love that Huck Valve and the adjustability over a stock shock.
So, again, thanks!!
I'm so old I still call it a delta link. 3 stroke, not to be a dick, but you should read up on what a rising rate does and why everybody more or less copied the "Pro Link"
The Beta suspension dept manager said that the knuckle was developed by the US team so they certainly felt a need for a much more progressive knuckle. It was not developed by the Italian HQs so Italy will need to test it and see if they like it and want to spec it for their production bikes. He said that if they did spec it for production, it would only be on their RX (motocross) models.
Beta is currently using the same knuckle on all their models, including their woods/ trail bikes. Bryce also mentioned a lot of the motocross testing was in the sand in Europe. A very linear rising rate linkage may make sense for a woods bike or someone racing sand, but for most motocross conditions, I believe many riders would want something more progressive, and for me, a vet rider that only rides mx, it was a major improvement. If you are a woods guy, this knuckle is probably not what you would want.
The MX Tech shock is nice, and you can avoid the issue I was experiencing because with the huck valve, you can set your LSC softer and maintain good bottoming resistance with the huck valve. I probably would have went the MX Tech route if the knuckle hadn't worked out so well.
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