Talk to me about how oval fork uppers are the future.

Saw this moto2 post earlier but how is this better than the carbon? Better flex per laptiime I guess.

 

Czysz did that on his bike years ago, lowers were weird shape.

 

Yep saw them on his R1 at a OMRRA club event and they had a non traditional damping system too

 

Without knowing anything and totally winging like all of the recently minted bridge, ship and aeronautical engineers, I have to imagine it has to do with tracking via flex plane while the bike is leaned over And stiffness under brakes

 

Fox is using a similar concept with their 38 mm MTB fork steerer tube being slightly oval for longitudinal stiffness.



Curious to hear about this non-traditional damping system though, y'all got links to articles about this?

 

The MotoCysz had fork sliders that were oval shaped but did not contain any actual damping or springs- the damping was handled by a shock mounted between the forks with a linkage. There was an article about the bike in RRW some years ago.

 

I cant find the pic of the oval moto 2 fork can someone point me to it?

 

The fork was basically just a slider right? It was actually damped by a more traditional shock.

 

Funneling F.Zappa: Strictly Commercial (for most).

That is not fair of course, there is some mechanical logic to this. The marketable value is there if these can be cheaply mass produced.

Just be about as useful as wings for most buyers.

 

Kinda of but not really. Yes there was a shock but the connection to the forks and the engineering of sliders was unique. I don't recall the exact details but I believe it was a patented design and he was trying to sell the forks to the OEMs to make some bucks. And these were done well before the C1

 

If I remember sliders were moving on bearings or something like that. Axle can move forward and back for trail change.
Shock up front is nothing unusual.

 

https://twitter.com/PeterBom4/status/1771264991649280380

 

Awesone thanks Bruce!

 

So much to take in, in these pictures! Thank you Bruce.

 

I remember seeing a design years ago that someone had created for MX bikes which did away with the upper and lower triple clamps...at least the clamping portion. He postulated that clamping the fork in that fashion squeezed the tube excessively and lead to stiction when the bushings inside would move past the clamped area. He designed a fork tube that had 2 ribs flairing out from the center of the fork slider with mounting holes that would instead allow the fork to bolt onto the triple clamps. This was in the early 90s I believe. Can't find any pictures of it online and I guess it was never really adopted anywhere.

 

With the Showa BPF design, it is absolutely possible to bind up the guts during hard track use by torquing the triples to even OEM spec. It's a cost effective, bad design. The chrome slider tube is the cartridge body. When it deflects, the piston can't move (freely). They doubled down on the new models by putting all the valving in one leg and all the spring adjustment in the other leg, MX style.

 

Yup.....I always wince when I see people really lay into the wrench on the fork pinch bolts during re-assembly lol, and I always get "slider" and "tube" mixed up I really wish a could find an online version of this article from a million years ago. It was either in either MXA, Dirtbike or Dirt Rider.....can't recall which.

I want to say the guy who built these forks was using a new Husky he just bought as the test mule. I remember in the article he commented that the stock front suspension was "unrideable" off the showroom. Best I could approximate it below, the forks looks otherwise similar to stock except for these "flanges" that extended out from the front and back sides of the fork and they would simply bolt into the triples that just acted as receivers rather than clamps. This in effect fully removed all the deformation that the 2 clamps would otherwise cause, also added a good bit more rigidity against fore/aft flex.....not sure how much of a good thing that is depending on how rigid the rider wants the front end to feel. If I remember correct the designer also said he could manufacture the the fork internals to much tighter tolerances because he didn't have to cope with the clamping deformation of the fork.

 

Have you seen how 'petite' SX/MX fork clamps are these days? I see more changes coming.

 

Yes, he used linear type ball bearings for movement with less stiction, but the fork seals caused a lot of drag.

 

Is just the outer aluminum tube oval, or is the "chrome" tube oval as well? It's hard to tell from the pictures.