P3R Crankshafts

[FSG]

What math went into deciding the rotation of the polygon in relationship to the centerline between the crank pin and the crankshaft centre?

It could easily have been different as the pix below show but the math/vectors would have come into play, any mechanical engineers want to provide some thoughts?

[No Cents]

  I'm just nothing but impressed with the looks of those flywheels every time I see them. I couldn't even stop and talk to them this year at the Expo because I know I would just want a set of them even worse if I did. 
  I hope someone will be able to answer your question...I know I certainly can't.

[Hilly13]

They do look the goods don't they.

[hulkss]

I hope someone will be able to answer your question...I know I certainly can't.

Here's my view: Peak cylinder pressure occurs just after top dead center during the power stroke. You would want a corner of the polygon pointing up the rods at that time so the flat opposite side was carrying the load into the flywheel.

[koko3052]

 

[FSG]

hulkss        that's my train of thought as well but thought I'd ask others 

[speedzter]

I'm sure there has been hours of CAD stress analysis/simulations done to arrive at the final design.
Anything else has to be speculation.

[jam65]

I like their product but S&S is still on my buy list based on $. Also, they want your current wheels in exchange. Mine are Darkhorse U.S. H beams and the only exchange that I have.

[sfmichael]

these are beautiful   

[PoorUB]

any numbers on how many they have sold? Failure rate?

[kd]

Is that a compound pinion shaft? It looks like a weld at the step behind the pinion gear flat.

[FSG]

No

[rbabos]

I seem to be looking at pics of 3 different wheels here. Alignment is different on all 3 of them so it means nothing in the big picture where the 3 points are set. It's either locked or not .What I'd like to know is how they get such a precise alignment each time. Hell of a concept here but wonder what the rebuild process is like if needed.
Ron

[koko3052]

Hey Ron, you need to re-read the second line in FSG's statement...and put your lookers on when looking at the other pics of the crankpin.
That crafty bugger has rotated the crank pin with an inserted photo.

[Ohio HD]

Hey Ron, you need to re-read the second line in FSG's statement...and put your lookers on when looking at the other pics of the crankpin.
That crafty bugger has rotated the crank pin with an inserted photo.

  Saw that too, but I also know where he got them.   

[rbabos]

Hey Ron, you need to re-read the second line in FSG's statement...and put your lookers on when looking at the other pics of the crankpin.
That crafty bugger has rotated the crank pin with an inserted photo.

1.5s to the rescue. I see that now. Never mind my stupidity.
Ron

[Hossamania]

Hey Ron, you need to re-read the second line in FSG's statement...and put your lookers on when looking at the other pics of the crankpin.
That crafty bugger has rotated the crank pin with an inserted photo.

1.5s to the rescue. I see that now. Never mind my stupidity.
Ron

Don't feel bad Ron, it took me a couple extra looks to figure out what was going on too.

[Ohio HD]

Hey Ron, you need to re-read the second line in FSG's statement...and put your lookers on when looking at the other pics of the crankpin.
That crafty bugger has rotated the crank pin with an inserted photo.

1.5s to the rescue. I see that now. Never mind my stupidity.
Ron

I use 2.0 or 2.5's   

[build it]

Rebuilds are done exclusively through p3r, standard is static balanced, you pay extra for dynamic  balancing. I don't see how this design would impede spread.

It does look like the crank pin is pressed into the polygon which is then pressed into the wheel. How would that eliminate slip? Am I seeing that pin arrangement correctly?

[PoorUB]

It does look like the crank pin is pressed into the polygon which is then pressed into the wheel. How would that eliminate slip? Am I seeing that pin arrangement correctly?

Pretty sure the round deal is a plug to seal off the hollow shaft. The ends of the pin are triangular.

[build it]

It does look like the crank pin is pressed into the polygon which is then pressed into the wheel. How would that eliminate slip? Am I seeing that pin arrangement correctly?

Pretty sure the round deal is a plug to seal off the hollow shaft. The ends of the pin are triangular.

You're probably right.

[BVHOG]

I think S&S has more than proved that a round pin can be made to hold up quite well. I don't care if you use a hex shaft for a pin, the rod  bearings will not hold up any better than any other setup

[HD/Wrench]

To me that looks like another version of a an item to stop the pin from moving. I doubt it really matters where you put it. Round pin with a triangle pressed on the end of it . could have been square or octagonal.. 3 points is less machine work .

I never spoke with them,... I tuned a bike that had that crank it from what the customer said . Do you know whos rod they use by chance FSG ? 

[No Cents]

   Steve...I asked them what rods they used a few years ago and they told me they basically offered different options for rods just like Darkhorse does. I'm pretty sure they told me the rods they had in their displayed flywheels at the Expo were Carillo...if memory serves me correct.
   The P3R guys said each set of flywheels are custom made to order from the options you choose. I got that info at the Expo a few years back when they 1st showed their product. I don't know if anything has changed since then because I just couldn't bring myself to stop at their booth this year and talk to them. I knew if I did...I would end up spending money that I don't need to right now.

Ray

[Don D]

Rods are Carillon now