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Leaf springs on your MX bike??

Looks like KTM is revamping the idea with a new pattens on an old Yami trick/

What say you all?
Rock on! The old timers talked of a canvas bag encapsulating the leafs in grease. No bobody thinks of siezed leafs. About as bad as siezed shackles. Kinda common in early bikes but is mainstream rv/trailer use unless torflex. A couple vtwin builders used torflex bushings in the front. Ahh full circle engineering.
 
Looks like KTM is revamping the idea with a new pattens on an old Yami trick/

What say you all?
Saw this the other day. With s swingarm, I don't see why not. Coupled with fiberglass or some other composite material it could be really cool.
 
I see it as Potentially good in that it would put probably less weight and above all weight low down on the frame. Less weight in upper frame structure and Leaver arm damping again low and with bigger oil capacity for cooling.
Simple is the part i like, and ok i acept the clamping area of the frame will need to be substantial, but any mass will be low in frame. The String/ springs will need to be quality to give good rates of progression but its a well known technology what with parabolic s or composite springs etc , its been used Hundreds of years and it works well. Why not i say whats not to like, i am surprised its been absent from bikes for so long.
 
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I'm honestly a bit surprised it hasn't been a thing for longer already, especially for racing. a little curious why they went that route versus a torsion spring, my general understand is torsion spring is better and kind of the next step up but it may be more practical on 4 wheels than two (for racing)
 
I'm honestly a bit surprised it hasn't been a thing for longer already, especially for racing. a little curious why they went that route versus a torsion spring, my general understand is torsion spring is better and kind of the next step up but it may be more practical on 4 wheels than two (for racing)
Tortion bars (springs) bars in the UK are good but AFAIK need to be a bit longer than the width of the typical bike frame , even in small car rear suspension they dont travel as well as the longer longitudinal mounted set up on the front of some older cars and even relatively new 4x4s .
Another thing about tortion bars is the anchor/ spline pivot points and arm anchor flanges need to be substantial and possibly weigh more than a 14 epiliptic leaf spring layout with only the clamping area needing to be a bit over engineered perhaps. The Mercedes sprinter vans had a transverse front leaf layoyot that is kind of half of what i see a good rear swing arm set up being in design anyway.
 
If this makes it to production, I hope the OEM(s) have a wide range of springs available for different weights.
One aspect of leaf springs is a fairly wide range of progression, this should make a multi leaf layout cover a bare bike and a heavily loaded bike a real option with no adjustment.
About the only area i can see issues here is the actual suspension travel.
Travel typical of coil spring will need to be a parabolic spring and not sure how a load leaf multi leaf set up will behave with such spring i imagine it will impair the progression and the movement too, kind of defeating both aims.
On bikes i imagine a simple parabolic will be best, but then we are back to your point of needing options re spring rates. There are potential pit falls but the simplicity and low weight of leaf springs imo outweigh the possible shortfalls in my opinion.
 
If this makes it to production, I hope the OEM(s) have a wide range of springs available for different weights.
I'm wondering if add-a-leaf type components will come in to play here. Retain the stock spring and just add wafers here and there as needed.


Would be pretty slick to have a properly sprung bike that you can clip an extra leaf on to when it comes time to toss on the luggage or a passenger.
 
Its a solution to a problem that doesn't exist.

Just like the front ends on a Bimota Tesi and Yamaha GTS.
I dunno. There's definitely a line somewhere between looking for a solution that nobody asked for, and a new idea that nobody has thought of/ implemented yet. I thought cellphones were the dumbest thing ever when they came out and begrudgingly carried one for work purposes. We see how that turned out 😁

Anything to make a bike lighter gets a nod from me. I mentioned this to a couple friends and both of them scrunched up their faces. "Antiquated leaf spring?!" It's not like coil springs are a modern invention 😁

Not that you said this, but the whole "antiquated" bellyaching I see in bike reviews lately gets old after a while. Yeah, yeah...only the newest and bestest could possibly keep up with your riding prowess. We get it. I'm happy with stuff that works. That that holds up. If they can fit it, it works better and weighs less then I see no drawbacks.
 
IDK. If the leafs are easy to change it might be a good set up for those of us that like to use the same bike for track and trail
 
I’m interested in seeing how they manage damping of the leaf oscillation
 
Leaf springs could be a good solution for certain applications. All a spring of any type does is store energy. Most types have some specific drawbacks that the other types don't have.
Coil spring does have advantage of length packed in a small space. Made from readily available inexpensive material. With well known characteristics.
KTM seem to be still using standard damper, so I don't see much packaging improvement.
A fiberglass swing arm, coupled to an AL body damper would reduce unsprung weight. That could work if the swinger could be predictable and tuned.
 
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