Header and Torque

Steve Clark clarks at nbnet.nb.ca
Sun May 30 21:40:26 PDT 2010

I feel the need to chime in and support Steve Northrop on the system being 
passive - it is all about helping burn off more toxic stuff in the exhaust 
flow.  I would ask you to consider that the air is drawn into the exhaust 
port after the cylinder has fired and the power has been made.  OK you could 
say that it is drawn in to the exhaust port by the exhaust pulse of another 
cylinder.  How ever the air gets in it is to the exhaust port which is after 
the cylinder explosion where the power is made.

When a bike goes on the Dyno for tuning we block off the fresh air source - 
not because we hope there will be more power but to ensure we get the most 
accurate Air fuel reading when we tune.  We do peak power pulls with and 
without the fresh air systems and the bike produces the same chart give or 
take some which is the case anyway - no two pulls are the same just very 
close and with the same shape of trace for HP and Trq.

Again I second Steve in that the only way to get your bike tuned is on a 
dyno and to get a bike correct it will be at least 2 hours and if it is 
carbs rather than EFI you should give the guy that takes the carbs off and 
puts them back on, sometimes several times, a tip for not burning your bike 
out of frustration.

I will share three things I have observed at the motor shop: 1. - I have yet 
to see a Jet kit set up work out of the box per the instructions.  2. Only 
one Power Commander Map has been correct out of hundreds and 3. - 100 mile 
an hour duct tape works well to close off the holes folks cut into their air 


Retired but somehow working more hours a week than when I worked

1997 GPZ1100
2000 ZX9
2002 Goldwing
2004 CBR600RR (Race Bike)

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