volroom
Race Dog
Thinking of getting a set: https://www.boxer-performance.com/products.htm
Obi-Wan (Deon) was thinking of getting a set, but is not interested anymore. i understand why; the GSA won't benefit as much as the GS because of the gearing specific to the GSA (1st and 6th gear, see below) They are $210 a set, incl. shipping. Around R2100, before VAT on this side.
The theory is that by advancing the cam timing, your opening and closing the valves a bit sooner, the trick seems to be that more fuel/air mixture gets trapped and compressed for the power stroke - as the inlet valve closes sooner as the piston starts to compress the air/fuel. This results in more torque lower down, moving the torque peak 800-1000RPM down the range. You do lose 1-2 BHP above 6500RPM. Very seldom I'm up that high on the tacho, but will need to learn to shift earlier with the sprockets fitted. The GS peak torque is around 5000RPM, so now it might be 4200RPM. With the long 6th, 4000+- RPM is where is cruise normally, so that should result in better fuel consumption (peak torque does not cost more petrol, but if your not there, you need more petrol as the efficiency is not what it can be), and roll-on acceleration. Also, fully loaded pulling away in first have seen me stall the engine before, especially up hill... Slipping the clutch often, will result in the need of a new clutch sooner. the sprockets will alleviate that. If your interested, have a look on ADVrider; search for Lennie's Rocket Sprockets. The guys that fitted them to their R1150GSs are quite happy. Some report better mileage, as much as 10% per tank. All report that the engine is smoother at lower RPM range, pulls better through the gears, and getting away in 1st is easier. It just makes sense to me, if you look at the torque curve for the R1150GS, it peaks above 5000RPM. therefore, for a GS, you need to be riding at around 160km/h in order for the engine to be producing peak torque in 6th. These bikes are way to heavy on fuel at that speed. Most cruise around 120-150km/h, I'd imagine. I normally do 140km/h, or 130km/h. You around 4000RPM then. Move the torque curve you see down 800-1000RPM, and you'll see what I mean. The guys on ADVrider also report that your able to ride one gear lower around-town speeds, so you'd have enough torque to be riding around at 2000RPM in 3rd, 4th and 5th, less shifting, less fuel. For the techno experts, do you think there's a caution to be taken before fitting these sprockets?
Obi-Wan (Deon) was thinking of getting a set, but is not interested anymore. i understand why; the GSA won't benefit as much as the GS because of the gearing specific to the GSA (1st and 6th gear, see below) They are $210 a set, incl. shipping. Around R2100, before VAT on this side.
The theory is that by advancing the cam timing, your opening and closing the valves a bit sooner, the trick seems to be that more fuel/air mixture gets trapped and compressed for the power stroke - as the inlet valve closes sooner as the piston starts to compress the air/fuel. This results in more torque lower down, moving the torque peak 800-1000RPM down the range. You do lose 1-2 BHP above 6500RPM. Very seldom I'm up that high on the tacho, but will need to learn to shift earlier with the sprockets fitted. The GS peak torque is around 5000RPM, so now it might be 4200RPM. With the long 6th, 4000+- RPM is where is cruise normally, so that should result in better fuel consumption (peak torque does not cost more petrol, but if your not there, you need more petrol as the efficiency is not what it can be), and roll-on acceleration. Also, fully loaded pulling away in first have seen me stall the engine before, especially up hill... Slipping the clutch often, will result in the need of a new clutch sooner. the sprockets will alleviate that. If your interested, have a look on ADVrider; search for Lennie's Rocket Sprockets. The guys that fitted them to their R1150GSs are quite happy. Some report better mileage, as much as 10% per tank. All report that the engine is smoother at lower RPM range, pulls better through the gears, and getting away in 1st is easier. It just makes sense to me, if you look at the torque curve for the R1150GS, it peaks above 5000RPM. therefore, for a GS, you need to be riding at around 160km/h in order for the engine to be producing peak torque in 6th. These bikes are way to heavy on fuel at that speed. Most cruise around 120-150km/h, I'd imagine. I normally do 140km/h, or 130km/h. You around 4000RPM then. Move the torque curve you see down 800-1000RPM, and you'll see what I mean. The guys on ADVrider also report that your able to ride one gear lower around-town speeds, so you'd have enough torque to be riding around at 2000RPM in 3rd, 4th and 5th, less shifting, less fuel. For the techno experts, do you think there's a caution to be taken before fitting these sprockets?
