SOME PROVEN TIPS and TRICKS for T135
- Thread starter haen
- Start date
Gagarinz
New Member
Hello guys,
Its long time not in contention in this forum..hehe its quite busy rite now.
So, a had a lot of modification on my ride compare to previous reply on page 8.
Rite now, my ride spec (additional) are as follows:
Cdi: BRT Smart Click = BTDC 31 degree, 12.5k rpm
Valve spring = Convert to racing
Bore = 58.5mm
CAM = Ride-it (low-CAM)
Valve clearance = 0.15 in, 0.15 out
Carb = Mikuni Flatslide 24mm (open air w/o filter) :?
So, need suggestion from the Expertice here.. for current condition;
1. Is it BTDC setting is correct if I turn to 31deg instead of bigger deg?
2. Is the valve clearance good enough or in-correct if I tend to have a top better speed? My machine also is quite noisy with this setting.
3. My pipe (ABM) sometimes create unstable sound and sometime it suddently gave "pom" like small explosion.
Does anybody could help me since I'm so naive in this modification field?
Its long time not in contention in this forum..hehe its quite busy rite now.
So, a had a lot of modification on my ride compare to previous reply on page 8.
Rite now, my ride spec (additional) are as follows:
Cdi: BRT Smart Click = BTDC 31 degree, 12.5k rpm
Valve spring = Convert to racing
Bore = 58.5mm
CAM = Ride-it (low-CAM)
Valve clearance = 0.15 in, 0.15 out
Carb = Mikuni Flatslide 24mm (open air w/o filter) :?
So, need suggestion from the Expertice here.. for current condition;
1. Is it BTDC setting is correct if I turn to 31deg instead of bigger deg?
2. Is the valve clearance good enough or in-correct if I tend to have a top better speed? My machine also is quite noisy with this setting.
3. My pipe (ABM) sometimes create unstable sound and sometime it suddently gave "pom" like small explosion.
Does anybody could help me since I'm so naive in this modification field?
The "Porting and Polishing" Myth
It is popularly held that enlarging the ports to the maximum possible size and applying a mirror finish is what porting is. However that is not so. Some ports may be enlarged to their maximum possible size (in keeping with the highest level of aerodynamic efficiency) but those engines are highly developed very high speed units where the actual size of the ports has become a restriction. Often the size of the port is reduced to increase power. A mirror finish of the port does not provide the increase that intuition would suggest. In fact, within intake systems, the surface is usually deliberately textured to a degree of uniform roughness to encourage fuel deposited on the port walls to evaporate quickly. A rough surface on selected areas of the port may also alter flow by energizing the boundary layer, which can alter the flow path noticeably, possibly increasing flow. This is similar to what the dimples on a golf ball do. Flow bench testing shows that the difference between a mirror finished intake port and a rough textured port is typically less than 1%. The difference between a smooth to the touch port and an optically mirrored surface is not measurable by ordinary means. Exhaust ports may be smooth finished because of the dry gas flow and in the interest of minimizing exhaust by-product build-up. A 300 - 400 Grit finish followed by a light buff is generally accepted to be representative of a near optimal finish for exhaust gas ports.
The reason that polished ports are not advantageous from a flow standpoint is that at the interface between the metal wall and the air, the air speed is ZERO (see boundary layer and laminar flow). This is due to the wetting action of the air and indeed all fluids. The first layer of molecules adheres to the wall and does not move significantly. The rest of the flow field must shear past which develops a velocity profile (or gradient) across the duct. In order for surface roughness to impact flow appreciably, the high spots must be high enough to protrude into the faster moving air toward the center. Only a very rough surface does this.
SOURCE : WIKIPEDIA
It is popularly held that enlarging the ports to the maximum possible size and applying a mirror finish is what porting is. However that is not so. Some ports may be enlarged to their maximum possible size (in keeping with the highest level of aerodynamic efficiency) but those engines are highly developed very high speed units where the actual size of the ports has become a restriction. Often the size of the port is reduced to increase power. A mirror finish of the port does not provide the increase that intuition would suggest. In fact, within intake systems, the surface is usually deliberately textured to a degree of uniform roughness to encourage fuel deposited on the port walls to evaporate quickly. A rough surface on selected areas of the port may also alter flow by energizing the boundary layer, which can alter the flow path noticeably, possibly increasing flow. This is similar to what the dimples on a golf ball do. Flow bench testing shows that the difference between a mirror finished intake port and a rough textured port is typically less than 1%. The difference between a smooth to the touch port and an optically mirrored surface is not measurable by ordinary means. Exhaust ports may be smooth finished because of the dry gas flow and in the interest of minimizing exhaust by-product build-up. A 300 - 400 Grit finish followed by a light buff is generally accepted to be representative of a near optimal finish for exhaust gas ports.
The reason that polished ports are not advantageous from a flow standpoint is that at the interface between the metal wall and the air, the air speed is ZERO (see boundary layer and laminar flow). This is due to the wetting action of the air and indeed all fluids. The first layer of molecules adheres to the wall and does not move significantly. The rest of the flow field must shear past which develops a velocity profile (or gradient) across the duct. In order for surface roughness to impact flow appreciably, the high spots must be high enough to protrude into the faster moving air toward the center. Only a very rough surface does this.
SOURCE : WIKIPEDIA
unlimited express
Super Veteran
hey haen, any new tricks for us?
wow another good tip bro haen.
sell it bro!
i guess thats much better than K&N oil filter for our bike
k&n oil filter is way expensive
sell it bro!
i guess thats much better than K&N oil filter for our bike
k&n oil filter is way expensive