NC35 and NC30 head interchangeability?
Posted: Sun Oct 16, 2011 2:47 pm
Does someone know if a complete cylinder head for an NC35 will bolt straight onto an NC30 and vice versa without any mods
http://www.400greybike.com/forum/
Doesn't the 35 have 1mm smaller valves?skinnydog0_0 wrote:35 cams have a different lift/duration over the 30 cams. The 35 cams are better. As far as i know the heads are the same possibly lighter on the 35.
Apparently soNeosophist wrote:Doesn't the 35 have 1mm smaller valves?skinnydog0_0 wrote:35 cams have a different lift/duration over the 30 cams. The 35 cams are better. As far as i know the heads are the same possibly lighter on the 35.
A good deal of the weight saved in the engine comes from the use of hollow camshafts. This also helps to reduce inertia. The NC35 exhaust cam is a slightly steeper profile; 1mm lift is achieved at 142-degrees, as opposed to 145-degrees on the NC30 cam (measured from 0-degrees cam angle). This will help speed up venting of the cylinder, effectively giving more opportunity for the rising piston to push out the exhaust gases. Total lift and duration are identical between engines.
The NC35’s inlet cam has a slightly longer duration; the extra 3-degrees are gained before effective opening, suggesting the cam initially opens the valve less aggressively, whilst still achieving the same total lift of 7.7mm.