Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Modified Ported Work or Race saws => Topic started by: Cut4fun on February 22, 2019, 07:45:01 am

Title: Full circle
Post by: Cut4fun on February 22, 2019, 07:45:01 am
Cant find the dang thread.

Saving pics

Jerry Gingras pic of MVP 272 cranks

Pic of my MVP 5000 partner crank

Title: Re: Full circle
Post by: SquareFile on May 05, 2021, 03:09:24 pm
https://youtu.be/GWngpdMzDJY
Title: Re: Full circle
Post by: Al Smith on June 22, 2021, 08:26:17 am
It's an interesting theory with f/c crank throws .Very popular during the glory days of 2 cycle go karts .I think the idea was to reduce the crankcase volume therefore increasing the transfer pressure .
The full circle cranks on Harley v twins was just to have the crank throws act as an internal flywheel plus it was much more simple to make .The actual design of that engine is a direct take off of a radial  aircraft engine except it only has two cylinders .
I have a theory the increased weight of the rotating mass with a full circle crank would some what increase the inertia mass regarding changing potential energy into kinetic  energy under load .--goes back to Newtons laws of physics .
Title: Re: Full circle
Post by: Cut4fun . on November 20, 2023, 04:54:59 pm
One of the mods in my FB CR group does full circle cranks.  Here is 372 and 4910 501 ones

Title: Re: Full circle
Post by: 3000 FPS on November 22, 2023, 12:56:09 pm
Quote from: Cut4fun . on November 20, 2023, 04:54:59 pm
One of the mods in my FB CR group does full circle cranks.  Here is 372 and 4910 501 ones


That is some nice looking cranks.   Some nice looking work. 
Title: Re: Full circle
Post by: SquareFile on February 04, 2024, 03:17:29 pm
Quote from: Cut4fun . on November 20, 2023, 04:54:59 pm
One of the mods in my FB CR group does full circle cranks.  Here is 372 and 4910 501 ones

One on right appears to be separating. The one on the left is scalloped "turbocrank" 70s bike tech that, well.... I've seen both. JMO, searching for big gains that aren't there. Carbs and porting is where it is at. Both are a 2fold.