Engine Mechanical Topics Discussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.

Polygon Crankpin technology for Twin Cam Flywheels

Thread Tools
 
Search this Thread
 
  #21  
Old 02-07-2017, 09:18 AM
Jackie Paper's Avatar
Jackie Paper
Jackie Paper is offline
Seasoned HDF Member
Join Date: Mar 2010
Location: Honah Lee
Posts: 35,430
Received 5,000 Likes on 4,191 Posts
Default

Originally Posted by prodrag1320
wrist pin??? how about crank pin
Long a go in the 60s in shop 101, the wrist pin of a crank was the pin that goes thru the big end of the connecting rod. If you google wrist pin now since you made me, it still does. Realize Harleys crank lobes are usually called wheels by me since they look more fly wheel like them lobes. My interest came anout this simply on a designer and machinest point locking and indexing the crank to prevent sissoring. Terry and I sent emails back and forth and he like you say is one cool dude to take his time in going into detail.
 
  #22  
Old 02-08-2017, 03:54 AM
Tat2u's Avatar
Tat2u
Tat2u is offline
Road Warrior
Join Date: Aug 2007
Location: South Australia
Posts: 1,392
Received 42 Likes on 38 Posts
Default

Originally Posted by Hillsidecycle.com
2, .250" hardened dowel pins pressed on the seam, 180 degrees apart from each other, on both sides of the crank, does work very well.
Scott
we call this style of locking "scotch keying" in Australia.
not used so much in Auto industry but in heavy fixed plant.
often drill and tap a thread and use a grub screw, loctited in..
 
  #23  
Old 02-08-2017, 06:42 AM
multihdrdr's Avatar
multihdrdr
multihdrdr is offline
Club Member
Join Date: Oct 2011
Location: Nor Cal
Posts: 11,011
Likes: 0
Received 2,313 Likes on 1,861 Posts
Default

Originally Posted by Tat2u
we call this style of locking "scotch keying" in Australia.
not used so much in Auto industry but in heavy fixed plant.
often drill and tap a thread and use a grub screw, loctited in..
And we call those Set screws here
 
  #24  
Old 02-08-2017, 01:30 PM
Tat2u's Avatar
Tat2u
Tat2u is offline
Road Warrior
Join Date: Aug 2007
Location: South Australia
Posts: 1,392
Received 42 Likes on 38 Posts
Default

Set screw here is a normal Allen key socket head bolt just with no shank, the thread gies all the way to the head, grub screw has no head, all thread with the female in hex for an Allen key...
 
  #25  
Old 02-08-2017, 03:35 PM
Jackie Paper's Avatar
Jackie Paper
Jackie Paper is offline
Seasoned HDF Member
Join Date: Mar 2010
Location: Honah Lee
Posts: 35,430
Received 5,000 Likes on 4,191 Posts
Default

Allen Socket head cap screw.. (usually grade 8 here in the US)
Allen set screw = (grub screw in UK) Quite often in the US on a fan in a heating system, the grub screw will have a square on it for those who do not have a set of Allen wrenches or maybe since that stuff gets all rusty and you can get it out if you are lucky with Vicegrip pliers.
 

Last edited by Jackie Paper; 02-08-2017 at 03:42 PM.
  #26  
Old 02-10-2017, 03:15 AM
Big J1's Avatar
Big J1
Big J1 is offline
6th Gear
Join Date: Jul 2014
Location: NOWHERE
Posts: 10
Received 0 Likes on 0 Posts
Default

Originally Posted by RIPSAW
The polygon shape you see in the wheel is the wrist pin. It is totally ground and basically is a press fit into the crank wheel of the crankshaft shouldered on the inside. Being so huge, it is only about .001 press. That smaller plug with company logo is a press fit plug of about .001 press interference fit into a blind hole in the wrist pin on the front face of the wheel. It tends to increase the overall press and retains the wrist pin while the polygon which is already pressed in, does the driving.
The original test bed was proven out in the owners 120 Harley.
Having talked to Terry Stewart The press fit on this is actually .009 Not .001.
 
  #27  
Old 02-10-2017, 08:07 AM
Jackie Paper's Avatar
Jackie Paper
Jackie Paper is offline
Seasoned HDF Member
Join Date: Mar 2010
Location: Honah Lee
Posts: 35,430
Received 5,000 Likes on 4,191 Posts
Default

Originally Posted by Big J1
Having talked to Terry Stewart The press fit on this is actually .009 Not .001.

What's a few thousands of an inch among friends?? HA.....

Actually, what I posted was from an email from him but sure it could have been updated since he is the racer and the technology is coming from the actual company that produces the the part. What I posted was from that email.
Don't have his email on my laptop and out of the country but how it was explained to me in email was too much press could result in a loss of dimensional accuracy do to shear rather then compression and could index the crank. The shape does the drive and of course the press holds it together somewhat. However, the finial squash is that oversize round pin that is pressed in the end that you see their signature engraved in. So, maybe what you are quoting is the total.
I was in the machine shop world for 46 years and .009 is a lot of press.
 
The following users liked this post:
Big J1 (02-19-2017)
  #28  
Old 02-11-2017, 02:59 PM
PWMORRIS's Avatar
PWMORRIS
PWMORRIS is offline
Road Captain
Join Date: Jan 2009
Posts: 714
Received 120 Likes on 93 Posts
Default

Crank looks good-only a handful actually out there running them at this time.
Wanna pay big bucks to be one of the first, with no results history of R&D/T&T/current/former users? Not me.

Run S&S and be done with it-move on to other areas of the motor and use the extra cash to make HP. I've run 200 HP on their standard crank/rods and over 225 N/A on S&S prostock crank/rods. NO ISSUES. Should be enough for most anyone posting here.
 
The following users liked this post:
msocko3 (02-11-2017)
  #29  
Old 02-19-2017, 03:30 AM
Big J1's Avatar
Big J1
Big J1 is offline
6th Gear
Join Date: Jul 2014
Location: NOWHERE
Posts: 10
Received 0 Likes on 0 Posts
Default

Originally Posted by RIPSAW
What's a few thousands of an inch among friends?? HA.....

Actually, what I posted was from an email from him but sure it could have been updated since he is the racer and the technology is coming from the actual company that produces the the part. What I posted was from that email.
Don't have his email on my laptop and out of the country but how it was explained to me in email was too much press could result in a loss of dimensional accuracy do to shear rather then compression and could index the crank. The shape does the drive and of course the press holds it together somewhat. However, the finial squash is that oversize round pin that is pressed in the end that you see their signature engraved in. So, I was in the machine shop world for 46 years and .009 is a lot of press.maybe what you are quoting is the total.
I am in the machine shop world for 35 years and you are right .009 is a lot of press.Below is the message I received from terry.

Hi Jerry.

I thought I would send you a private message to let you know that if you'd like to call me feel free. But I did want to let you know that the polygon is pressed in with a .009" interference fit !
 
  #30  
Old 11-22-2021, 08:07 PM
Cougr68's Avatar
Cougr68
Cougr68 is offline
Stage II
Join Date: Nov 2021
Location: Westchester
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default Polygon crankpin

Originally Posted by RIPSAW
The polygon shape you see in the wheel is the wrist pin. It is totally ground and basically is a press fit into the crank wheel of the crankshaft shouldered on the inside. Being so huge, it is only about .001 press. That smaller plug with company logo is a press fit plug of about .001 press interference fit into a blind hole in the wrist pin on the front face of the wheel. It tends to increase the overall press and retains the wrist pin while the polygon which is already pressed in, does the driving.
The original test bed was proven out in the owners 120 Harley.
The person that is trying to sell this pin, stole it from my friend and patented it behind my friends back. He is a thief. My friend Has the bike and test engine.
 


Quick Reply: Polygon Crankpin technology for Twin Cam Flywheels



All times are GMT -5. The time now is 06:16 PM.