New Beta RX

New 125 or 350 2-stroke.  Or maybe a 250 RX 4-stroke.

https://www.facebook.com/reel/729390239434583?fs=e&mibextid=wwXIfr&fs=e

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cbarber
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6/5/2025 5:41am

i can't tell if that says 250 or 350

AMetts
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6/5/2025 6:16am

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

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The Shop

soggy
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6/5/2025 6:19am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

15!? That sounds crazy…

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ktmracer726
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6/5/2025 6:22am Edited Date/Time 6/5/2025 6:25am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX. 

2023 KTM 300 SX's Horsepower and Torque | Dirt Rider

How Much Power Does the 2023 Beta 300 RX Make? | Dirt Rider

 

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AMetts
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6/5/2025 6:26am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

soggy wrote:

15!? That sounds crazy…

Your right I was comparing dyno numbers to claimed numbers looks like Dirt Rider dynoed both with the Beta at 41 and the KTM at 49.

Not that I think they need more power but I don't see them selling a ton of these 350s, granted with them being carbureted it is pretty easy to put a bigger jug and do some jetting and have a whole new model. 

It appears to be a moto bike which is probably the best use for a 350 2t. 

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AMetts
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6/5/2025 6:28am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX.   

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX. 

2023 KTM 300 SX's Horsepower and Torque | Dirt Rider

How Much Power Does the 2023 Beta 300 RX Make? | Dirt Rider

 

Yeah I did a quick google and was comparing KTMs claimed 57hp to the dyno tested beta at 40. I only brought it up because I have ridden both and that was the first thing that came to mind is one felt a lot more timid, its also more fair to compare the beta to the XCW which has probably even less HP than the Beta in stock form. 

wrc777
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6/5/2025 11:10am

I can definitely read the 2t on the shroud. It looks like it says 350 in the bigger numbers. 

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Broseph
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6/5/2025 11:13am

Dirt Rider’s dyno is a little special. It reads roughly 10% lower than the rest of the magazines. 

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burn1986
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6/5/2025 11:20am Edited Date/Time 6/5/2025 11:20am

I would imagine the 350 will be a 250 bored out (similar to the 200, which is a 125 bored out).

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6ully
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6/5/2025 11:49am

That is most definitely a '3'. 350 2t sounds amazing.

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mx1234
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6/5/2025 12:42pm

250 four stroke

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Press516
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6/5/2025 8:41pm
mx1234 wrote:

250 four stroke

That’s what they need…. That’s not what the photo is.  😉

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cappelmans
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6/5/2025 8:59pm
cbarber wrote:

i can't tell if that says 250 or 350

380?!? 🤓

Bearuno
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6/5/2025 11:06pm Edited Date/Time 6/7/2025 12:01am
burn1986 wrote:

I would imagine the 350 will be a 250 bored out (similar to the 200, which is a 125 bored out).

As I've put up a few times - the specs shown at EICMA last year:Beta 350 2t %2Bat EICMA 2024 -  SpecificationsWhy  A 350?

Why the hell not?

Something different, and as those Big Bad 300s are deemed too 'Scary' for 450s to compete with, in the highest series there are,  well, they are an 'orphan' already - so, why not a bigger, different one?

It can compete in the E3 class in EWC - it is being used this year.

Should be a good thing, and give Beta a marketing 'extra', at, what I would think, Not a huge development and production expense. 

Any new 2 stroke, is a Good 2 stroke!

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bvm111
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6/5/2025 11:12pm

evidently Beta was at GH today with something for Keefer to test. 

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avidchimp
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6/6/2025 7:49am

350 RR X-Pro.

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LungButter
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6/6/2025 7:58am

I'm in the "I don't really see the point of a 350 2 stroke" club as well.

Yes, I know the point is fun obviously, but is there really enough people that want one to make it viable?

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burn1986
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6/6/2025 8:00am Edited Date/Time 6/6/2025 8:08am
Bearuno wrote:
As I've put up a few times - the specs shown at EICMA last year:Why  A 350?Why the hell not?Something different, and as those Big Bad...

As I've put up a few times - the specs shown at EICMA last year:Beta 350 2t %2Bat EICMA 2024 -  SpecificationsWhy  A 350?

Why the hell not?

Something different, and as those Big Bad 300s are deemed too 'Scary' for 450s to compete with, in the highest series there are,  well, they are an 'orphan' already - so, why not a bigger, different one?

It can compete in the E3 class in EWC - it is being used this year.

Should be a good thing, and give Beta a marketing 'extra', at, what I would think, Not a huge development and production expense. 

Any new 2 stroke, is a Good 2 stroke!

Agreed. I just hope it’s a stand alone 350 and not a 250 big bore. I’ll have to look at the bore and stroke to tell. Steve Lamson did something similar (back in 89) with a 250 bored out to a 360.

IMG 0250 1.jpeg?VersionId=s06Md1AWFF
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agn5008
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6/6/2025 8:01am

Kawasaki should take note. This is how you tease a new model. 

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6/6/2025 8:05am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX.   

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX. 

2023 KTM 300 SX's Horsepower and Torque | Dirt Rider

How Much Power Does the 2023 Beta 300 RX Make? | Dirt Rider

 

That dyno is for the 23' model.

 

The 25' is a very different motorcycle.

 

Additionally, it looks like info on the 26' RR-X Pro is on the Beta website-  All Red.

 

The teaser is for the RX line releasing Tues

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Saz
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6/6/2025 8:14am

People not seeing the point of the 350 2 stroke, but still wanting the 500 2 strokes to come back.

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KurtJ99
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6/6/2025 8:21am Edited Date/Time 6/6/2025 8:22am
wrc777 wrote:

I can definitely read the 2t on the shroud. It looks like it says 350 in the bigger numbers. 

And silencer looks like a 2T, definitely not 4T. 

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Bearuno
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6/6/2025 8:26am
burn1986 wrote:
Agreed. I just hope it’s a stand alone 350 and not a 250 big bore. I’ll have to look at the bore and stroke to tell...

Agreed. I just hope it’s a stand alone 350 and not a 250 big bore. I’ll have to look at the bore and stroke to tell. Steve Lamson did something similar (back in 89) with a 250 bored out to a 360.

IMG 0250 1.jpeg?VersionId=s06Md1AWFF

Here's some numbers for you

Beta 250 - 66.4mm Bore x 72mm stroke.

Beta 300 - 73mm bore x 69.9mm Stroke. They've stepped away from the 'square' engine which is  the near norm ( and 'easy upping') for 300s. Perhaps to combat the loss of revs some complain about with the 250 to 300 conversion - it's a delicate balance with piston speed from stroke length, and , weight of a bigger piston. And, port sizing / duration enabled by both dimensions.

The Beta 350 - as on that EICMA spec board, and, it could be different to that - 78mm Bore x 73.6mm Stroke. 

It will, one assumes, be a somewhat different animal. Without the low revs, and, 'brutishness' of a full 500. Though, even Battered Old Bastards, such as I,  can deal with that,   so long as you mainly ride the Pilot Jet circuit Hard, and the Needle / Needle Jet circuit calmly, and, the Main Jet circuit, rarely.......😁😉

 

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bultokid
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6/6/2025 9:26am
AMetts wrote:
Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to...

Who is asking for a 350 two stroke? The 300s lug plenty and have more than enough power although Betas 300 is down atleast 15hp to the KTM. 

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX.   

Those numbers don't seem right for either bike. Most bike mags claim 55 HP for the KTM 300 SX. 

2023 KTM 300 SX's Horsepower and Torque | Dirt Rider

How Much Power Does the 2023 Beta 300 RX Make? | Dirt Rider

 

AMetts wrote:
Yeah I did a quick google and was comparing KTMs claimed 57hp to the dyno tested beta at 40. I only brought it up because I...

Yeah I did a quick google and was comparing KTMs claimed 57hp to the dyno tested beta at 40. I only brought it up because I have ridden both and that was the first thing that came to mind is one felt a lot more timid, its also more fair to compare the beta to the XCW which has probably even less HP than the Beta in stock form. 

I'm on a '23 300RX and riding buddies have '23 and '24 300SXs. Both great bikes IMO, i feel the KTM is little better MX bike but the Beta sure handles good and it doesn't give up much motor wise. Can't go wrong with either.  The '25+ are definitely more MX focused.  

I'd pay to see SuperDave ripping on the new '26 350RX !!!!!

 

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burn1986
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6/6/2025 9:28am Edited Date/Time 6/6/2025 9:29am
Bearuno wrote:
Here's some numbers for youBeta 250 - 66.4mm Bore x 72mm stroke.Beta 300 - 73mm bore x 69.9mm Stroke. They've stepped away from the 'square' engine...

Here's some numbers for you

Beta 250 - 66.4mm Bore x 72mm stroke.

Beta 300 - 73mm bore x 69.9mm Stroke. They've stepped away from the 'square' engine which is  the near norm ( and 'easy upping') for 300s. Perhaps to combat the loss of revs some complain about with the 250 to 300 conversion - it's a delicate balance with piston speed from stroke length, and , weight of a bigger piston. And, port sizing / duration enabled by both dimensions.

The Beta 350 - as on that EICMA spec board, and, it could be different to that - 78mm Bore x 73.6mm Stroke. 

It will, one assumes, be a somewhat different animal. Without the low revs, and, 'brutishness' of a full 500. Though, even Battered Old Bastards, such as I,  can deal with that,   so long as you mainly ride the Pilot Jet circuit Hard, and the Needle / Needle Jet circuit calmly, and, the Main Jet circuit, rarely.......😁😉

 

So we’ll just have to wait and see if it’s based off a 250 or it’s a stand alone bike. 

(Similar to the pre-‘15 KTM 150/144. Post ‘15 was 125 based)

Broseph
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6/6/2025 10:35am Edited Date/Time 6/6/2025 10:35am
Bearuno wrote:
Here's some numbers for youBeta 250 - 66.4mm Bore x 72mm stroke.Beta 300 - 73mm bore x 69.9mm Stroke. They've stepped away from the 'square' engine...

Here's some numbers for you

Beta 250 - 66.4mm Bore x 72mm stroke.

Beta 300 - 73mm bore x 69.9mm Stroke. They've stepped away from the 'square' engine which is  the near norm ( and 'easy upping') for 300s. Perhaps to combat the loss of revs some complain about with the 250 to 300 conversion - it's a delicate balance with piston speed from stroke length, and , weight of a bigger piston. And, port sizing / duration enabled by both dimensions.

The Beta 350 - as on that EICMA spec board, and, it could be different to that - 78mm Bore x 73.6mm Stroke. 

It will, one assumes, be a somewhat different animal. Without the low revs, and, 'brutishness' of a full 500. Though, even Battered Old Bastards, such as I,  can deal with that,   so long as you mainly ride the Pilot Jet circuit Hard, and the Needle / Needle Jet circuit calmly, and, the Main Jet circuit, rarely.......😁😉

 

burn1986 wrote:
So we’ll just have to wait and see if it’s based off a 250 or it’s a stand alone bike. (Similar to the pre-‘15 KTM 150/144. Post...

So we’ll just have to wait and see if it’s based off a 250 or it’s a stand alone bike. 

(Similar to the pre-‘15 KTM 150/144. Post ‘15 was 125 based)

What I wouldn’t give for a KTM style counterbalancer in this new 350. A truly smooth big bore would be a dream come true. 

Tokyo_Tiddler
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6/6/2025 3:32pm

If a 350cc 2T, and if they are using the same size cranks as the 300/250, I would be worried about more vibration from swinging a bigger piston around. Vibration and a lot of 2T power, unless it is a very soft hit with linear power just screams arm pump Smile

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