The Spares Company
Club Shop/Regalia
Parent Website
Contact Officials
Machine Registrar
Club Secretary
Membership Secretaries
MPH Editor and Forum Administrator.
Section Newsletters
Technical Databases
Photos
Home
What's new
Latest activity
Forums
New posts
What's new
New posts
Latest activity
Information
Bike Modifications
Machine Data Services
Manufacturers Manuals
Spare Parts Listings
Technical Diagrams
Whitakerpedia (Vincent Wiki)
The Club
MPH Material Archive
Flogger's Corner
Obituaries
VOC Sections
Local Sections
Local Section Newsletters
Miscellaneous
Club Assets
Club History
Club Rules
Machine Data Services
Meeting Documents
Miscellaneous
Essential Reading
Magazine/Newspaper Articles/Letters
Adverts and Sales Brochures
The Mighty Garage Videos
Bikes For Sale (Spares Company)
Log in
Register
What's new
New posts
Menu
Log in
Register
Install the app
Install
Home
Forums
Forums: Public Access
Tech. Advice: Series 'B' / 'C' 500cc/1000cc Bikes
compression ratios
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="davidd" data-source="post: 97474" data-attributes="member: 1177"><p>Tim,</p><p></p><p>I am not sure where you are going. The static CR is not of much use because it only exists on the piston box, not the engine. Measuring the pressure in the engine will determined by the cam, whereas the static CR assumes that there are no valves or cam in the engine, just a pressure gauge in the spark plug hole. You could make your own chart. The Wallace DCR Calculator can be used. Just don't fill in anything for the boost.</p><p></p><p><a href="http://www.wallaceracing.com/mobile/dynamic-cr.php" target="_blank">http://www.wallaceracing.com/mobile/dynamic-cr.php</a></p><p></p><p>So, the fill-in looks like this:</p><p>[ATTACH=full]22811[/ATTACH]</p><p></p><p>When you press "Calculate" the following will display:</p><p>[ATTACH=full]22812[/ATTACH]</p><p>I think the numbers are correct for a stock Vincent, but I did not double check them. You can't use seat to seat specs for most Vincent cams as the valves are open most of the time and close only momentarily due to the irregularities on the base circle. Megacycle cams are the exception.</p><p></p><p>You can run the numbers with different static CR's and note the pressure, then work backwards from the pressure numbers. It will be different with a Mk1.</p><p></p><p>David</p></blockquote><p></p>
[QUOTE="davidd, post: 97474, member: 1177"] Tim, I am not sure where you are going. The static CR is not of much use because it only exists on the piston box, not the engine. Measuring the pressure in the engine will determined by the cam, whereas the static CR assumes that there are no valves or cam in the engine, just a pressure gauge in the spark plug hole. You could make your own chart. The Wallace DCR Calculator can be used. Just don't fill in anything for the boost. [URL]http://www.wallaceracing.com/mobile/dynamic-cr.php[/URL] So, the fill-in looks like this: [ATTACH=full]22811[/ATTACH] When you press "Calculate" the following will display: [ATTACH=full]22812[/ATTACH] I think the numbers are correct for a stock Vincent, but I did not double check them. You can't use seat to seat specs for most Vincent cams as the valves are open most of the time and close only momentarily due to the irregularities on the base circle. Megacycle cams are the exception. You can run the numbers with different static CR's and note the pressure, then work backwards from the pressure numbers. It will be different with a Mk1. David [/QUOTE]
Insert quotes…
Verification
What was Mr Vincent's Christian Name?
Post reply
Home
Forums
Forums: Public Access
Tech. Advice: Series 'B' / 'C' 500cc/1000cc Bikes
compression ratios
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
Accept
Learn more…
Top