Home Page Norton Parts For Sale Replica Honda Drum Brakes Works Benelli Replica The Bennett Collection
Big End Bearings Restorations Racing Achievements Links Contact information Engine Development & Current Project
Cam Technical Information
Inlet / Exhaust |
Cam Number |
Duration @ .004" Lift |
Duration @ .050" Lift |
Max Lift |
Max Opening Velocity (Thou Per Degree) |
Max Deceleration (Thou Per Degree Per Degree) |
Additional Comments |
Orginal Norton Cams (Norton Numbers) |
|||||||
Inlet |
6212 |
304° |
250° |
.398" |
9.1 |
-0.22 |
500 Inter |
Inlet |
11587 |
307° |
254° |
.426" |
10.2 |
-0.27 |
500 Manx |
Inlet |
6466 |
298° |
246° |
.409" |
9.6 |
-0.21 |
350 |
Exhaust |
6213 |
305° |
251° |
.394" |
8.8 |
-0.22 |
500 Inter |
Exhaust |
11588 |
315° |
262° |
.405" |
9.1 |
-0.22 |
500 Manx |
Exhaust |
6389 |
318° |
259° |
.380" |
8.2 |
-0.20 |
350 |
Ian Bennett Engineering Special Cams (My Numbers) |
|||||||
Inlet |
11587 * 20° |
327° |
274° |
.426" |
10.2 |
-0.27 |
Norton + 20° |
Inlet |
1471 |
323° |
277° |
.482" |
11.3 |
-0.23 |
Roller Rockers Only Reduced Base Circle |
Exhaust |
1503 |
304° |
258° |
.433" |
11.1 |
-0.24 |
Roller Rockers Only |
Inlet |
1339 |
300° |
258° |
.475" |
9.6 |
-0.23 |
Roller Rockers Only Reduced Base Circle |
Exhaust |
1340 |
324° |
278° |
.430" |
9.4 |
-0.23 |
Roller Rockers Only |
Exhaust |
1563 |
280° |
238.5° |
.400" |
11.1 |
-0.27 |
Roller Rockers Only |
Inlet |
1564 |
280° |
234° |
.450" |
11.3 |
-0.28 |
Roller Rockers Only Reduced Base Circle |
Inlet |
1565 |
280° |
238.5° |
.422" |
11.3 |
-0.28 |
Roller Rockers Only |
Key - = Cams Currently used in our Bike (500 Inter)
Interesting Points (Relating to Original Norton Cams)
1. All Norton cams are not the same duration which is why Norton tell you to time up Inlet opening & Exhaust closing.
2. Racing Cams (11587 & 11588) have higher acceleration rates - resulting in higher wear rates than 6212 & 6213 road cams.
3. As you would expect the 350 Cams have a lower max deceleration resulting in higher rev's before valve control is lost (Valve bounce).