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Discussion Starter #21
what rocker weight do you work to and how do you distribute it calculation wise for balance?
That's a good question !!!!

Very difficult to have good information
Some say to go on 108% of the piston before, other 70% ....
 

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Discussion Starter #23
Off course, I design the rocker according to that
 

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Discussion Starter #25
This engine is just for fun and it's more fun to make a rocker (from my point of view) :giggle:

The last rocket Design :
975523


Weight : 360gr
Weight at mid stroke on the rod axle withe pin : between 350.5gr (solid pin) and 270gr (drilled pin), not so bad

And I can still lighten the rocker if needed
 

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Discussion Starter #26
Work in progress :
Rocker case at home !

 

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Wow! So much time and money to make a slower bike ! A Ducati version of a Buell Blast.
 

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Looking good, Sam:)
This guy, Chris Cosentino, is designing something similar, though at a much higher level.
US Moto2 Bike

Very knowledgeable and communicative, you could ask him about the balancing problem.
[email protected] , search for " Digest #4602 ".
 

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Discussion Starter #29
Thanks @highflyer

Impossible to see the yahoogroups discution, I'm a member of the group however

I will start a discussion by email
 

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Discussion Starter #30
Some news :







And a video :

 
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Looks good, Samuel.(y)

Managed to find some time to debug my code.
Below are some graphs from testing it with 1m long rocker, and moment of inertia equivalent to (piston + upper rod) mass, at the 1m radius.
The forces are what the main bearings experience.
If you want to see how your set-up behaves, send me the measurements of your upper con-rod and complete piston masses along with the moment of inertia of the rocker from the CAD drawing.

Regards

Angelo
979621
979622
 

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Discussion Starter #32
Work in progress :

 
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Discussion Starter #33
Engine in the 848 frame !
749 Dark fork OK
But not the 748 tank with the 1198 airbox :cry:



Rocker oil circuit OK






For the moment 999 rear swingarm



I search a water radiator smaller than that of 748 (which is twisted ...), Do you have any ideas?
 

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If you keep the rear piston for balancing, I assume you run it with no rings ? That would seem like a lot of friction from the piston. Has anyone tried Teflon buttons in the skirt to reduce friction ? Has anyone tried a reed valve in the “head” to release pressure ? Those holes in the piston affect balance weight but don’t appear to be enough to eliminate all pressure. The rod big end could be made heavier to keep the engine balanced.
 

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Discussion Starter #35
You shouldn't have read everything I wrote ...
 

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Discussion Starter #36
One ring on the rear piston for good guidance
But I never did this montage
 

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Discussion Starter #37
Some news from my Project :


Work on wiring harness, I hâte it.....
Based on S2R 1000 wiring because I was offre a NEMESIS from S2R
993422



993423

993424
 
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Looking bloody good! Nice fairing too, do you mind if I ask what it is, who supplied it? (749/999 owner here, I need all the aesthetic assistance I can get....)

I always wonder about the weight distribution of Supermono's and this sort of project: wouldn't lopping the horizontal cylinder instead of the vertical give a more centralised mass and better weight transfer under braking/accelration? Does a lower CoG (losing vertical cylinder/head) give a tendency to push the front end as per the ill-fated upside down NSR500:

993507


Another interesting CoG article here: the craziest bike we’ve ever seen - Fastbikes

Our old tarted up Pantah engines also result in a short swingarm and not quite enough forward weight distribution, losing the front cylinder would allow all sorts of options to move the engine forward and lengthen the swingarm. Not easy with our trellis frames, but hey, if you can dream up this sort of beautiful rocker arrangement cutting and shutting a few frame tubes is a 5 minute job!

Thanks for sharing your (very cool) project.
 
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