? For Cb160 gents and gals
- Thread starter Texasstar
- Start date
Not really but the exhaust port is a huge blockage waiting to be ported. That ridge is usually on the floor where it does tend to act as an anti reversion dam. Don't remove that, but focus on the roof of the port where there is a lot of meat before you breakthrough into the spring pocket. You can also widen the port as it goes around the corner.
BTW a stock CB200 head flows more gas on both sides than a ported CB160. Just sayin'
BTW a stock CB200 head flows more gas on both sides than a ported CB160. Just sayin'
Texasstar
Can't is a four letter dirty word
I found this pix of a 160 head on the honda twin site and was wondering what that blockage was? Thanks Teazer!teazer said:Not really but the exhaust port is a huge blockage waiting to be ported. That ridge is usually on the floor where it does tend to act as an anti reversion dam. Don't remove that, but focus on the roof of the port where there is a lot of meat before you breakthrough into the spring pocket. You can also widen the port as it goes around the corner.
BTW a stock CB200 head flows more gas on both sides than a ported CB160. Just sayin'
I am reading Michael Moores 20 page 160/175 racer in it he says, "Weld should be added to raise the floor of the exhaust port as the stock port has too tight of a radius after the valve seat. It is interesting to note how an exhaust port being tested on a flow bench improves in flow as the bottom of the port is filled in with clay - making the port smaller! In stock configuration the lower half of the port doesn't do anything except promote unwanted turbulence."
Is this the sideways D shape that you have suggested?