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
Camshaft
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="Deleted member 3831" data-source="post: 105245"><p>Roy,</p><p>The Americans found this out some years back when they devised the Spintron equipment and discovered there could be a big variation between static and dynamic valve actuation. Originally designed to observe the flex of pushrods, it was quickly expanded to cover all components of the valve train, and the variations that were found to occur between the static and the dynamic valve actuation were a big eye opener.</p><p></p><p>TT</p><p> I attach a graphic to show overlaid traces of measured cam data, the MK 2 profiles and those of the 105.</p><p>The intake lobes are both aligned exactly one on top of the other, and in addition to the cam lift, the graphic also includes the velocity traces. You just cannot get this kind of graphic from rough data. The traces show where discrepancies occur between the two cams, even though the 105 was said to be a copy of the MK 2 but with the lobe separation increased. If required a section from anywhere on the graph may be enlarged (zoomed), by four times if needed. All the top cam grinding companies now have CNC grinders although the older Churchill and Berco machines still handle a lot of the run of the mill grinds The CNC machines run from data files which contain data to 8 decimal places.</p><p></p><p>Greg</p><p> I agree with your 'stone age' comment, but it doesn't need to stay that way. I guarantee the Horner brothers didn't operate that way when deloping their Vincent racers.</p><p></p><p>Anyone sufficiently interested in this subject would do well to obtain a copy of Jeff Williams book "Introduction to the Analytical Methods for Internal Combustion Engine Cam Mechanisms".</p><p>Jeff designed the cams for the ILMOR 265E engine (V8 pushrod) that won the INDY 500 in 1994</p></blockquote><p></p>
[QUOTE="Deleted member 3831, post: 105245"] Roy, The Americans found this out some years back when they devised the Spintron equipment and discovered there could be a big variation between static and dynamic valve actuation. Originally designed to observe the flex of pushrods, it was quickly expanded to cover all components of the valve train, and the variations that were found to occur between the static and the dynamic valve actuation were a big eye opener. TT I attach a graphic to show overlaid traces of measured cam data, the MK 2 profiles and those of the 105. The intake lobes are both aligned exactly one on top of the other, and in addition to the cam lift, the graphic also includes the velocity traces. You just cannot get this kind of graphic from rough data. The traces show where discrepancies occur between the two cams, even though the 105 was said to be a copy of the MK 2 but with the lobe separation increased. If required a section from anywhere on the graph may be enlarged (zoomed), by four times if needed. All the top cam grinding companies now have CNC grinders although the older Churchill and Berco machines still handle a lot of the run of the mill grinds The CNC machines run from data files which contain data to 8 decimal places. Greg I agree with your 'stone age' comment, but it doesn't need to stay that way. I guarantee the Horner brothers didn't operate that way when deloping their Vincent racers. Anyone sufficiently interested in this subject would do well to obtain a copy of Jeff Williams book "Introduction to the Analytical Methods for Internal Combustion Engine Cam Mechanisms". Jeff designed the cams for the ILMOR 265E engine (V8 pushrod) that won the INDY 500 in 1994 [/QUOTE]
Insert quotes…
Verification
The Series 'A' Rapide was known as the '********' Nightmare?
Post reply
Home
Forums
Forums: Public Access
Tech. Advice: Series 'B' / 'C' 500cc/1000cc Bikes
Camshaft
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