Boxerworks.com

Installation Instructions
For the R50/5 to R100/7 (up to 1979) motors (intake valve 42mm, exhaust valve 38mm or
40mm), because of the greater valve lift of the 336° camshaft (10.68mm, as opposed to
8.62mm for the 284° and 9.40mm for the 308° camshaft) the valve pockets in the pistons must
be made deeper at the edge. (See the following table, as well as Figure 1, Detail “B”.)
Clearance between valve and piston at overlap – TDC
Valve crank ° clearance additional milling of the valve pocket bottom.
Exhaust 3° BTDC 2.3mm 0.4mm
Intake 3° ATDC 2.3mm 0.4mm
Camshaft with 3° retarded slot
Exhaust 3° ATDC 2.7mm -
Intake 9° ATDC 2.0mm 0.7mm

I'm up in Humboldt County on a slow connection so I'll make this brief. I'll post the full info I have on the 336 cams once I'm home - too difficult to do on this slow remote terminal to my home servers.

Others can address issues of the measuring combustion chamber volume with heads in situ - I've done it but figure its being addressed already.

Very brief not re cams:
http://falcons.dyndns.org/links/open/bm ... te_std.jpg

Picture of nose of stock cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Picture of nose of 336 factory cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Have fun, John

It may be worth mentioning that the capacity of the cylinders of a 247 series engine is cast on the flanges of said cylinders... unless they've been bored out of course.

Rob

John Falconer wrote: Picture of nose of stock cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Picture of nose of 336 factory cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Have fun, John

Aren't all those cam noses from bikes with bean can ignitions? I have points.

Rob Frankham wrote:It may be worth mentioning that the capacity of the cylinders of a 247 series engine is cast on the flanges of said cylinders... unless they've been bored out of course.

Rob

Where is the flange? I've got "7" stamped on the cylinder base and "730 1182" cast into the fin closest the head gasket.

Tim Shepherd wrote:

John Falconer wrote: Picture of nose of stock cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Picture of nose of 336 factory cam:
http://falcons.dyndns.org/links/open/bm ... ew_std.jpg

Have fun, John

Aren't all those cam noses from bikes with bean can ignitions? I have points.

Yes.