Hi guys!
I have been using a manual clutch 70cc ht engine for a few years now and it just keeps on going, so just for fun i decided that it would be fun to buy a 70c centrifugal clutch engine with pull-start to use on days when i feel to lazy to use a clutch lever and pedel-start .
got it mounted on a new bike and it runs but i'm not happy with it's performance. could it be that these engines with centrifugal clutch have a much lower top speed/rpm then a manual clutch engine???
the old engine on a much heavier bike does easy 50kph (31mph) but the new one struggles to get upp to 35kph (21mph). it also drinks alot more fuel, old one(manual) does 0.18-0.20 liters per 10km (0.047-0.055mpg) whilst the new one(centrifugal) does 0.25-0.30 liters per 10km(0.065-0.080mpg).
I have the needle lowered as much as i can in the carb and it still gets abit to much fuel so i thought bad carb. switched it out for an other one with same result. ok checked electric if it gets bad spark, and yes a little weak.
changed spark, same result, so switched cdi no better spark.
now i have changed to whole electrical system with no improvement.
I've checked for air-leaks in the intake ans sealed the carb/intake manifold good with flench sealant and o-rings so no air-leaks there.
i have even tried an other exhaust system to see if it was a back pressure issue nothing seams to help.
Anyone having any thoughts???
I have been using a manual clutch 70cc ht engine for a few years now and it just keeps on going, so just for fun i decided that it would be fun to buy a 70c centrifugal clutch engine with pull-start to use on days when i feel to lazy to use a clutch lever and pedel-start .
got it mounted on a new bike and it runs but i'm not happy with it's performance. could it be that these engines with centrifugal clutch have a much lower top speed/rpm then a manual clutch engine???
the old engine on a much heavier bike does easy 50kph (31mph) but the new one struggles to get upp to 35kph (21mph). it also drinks alot more fuel, old one(manual) does 0.18-0.20 liters per 10km (0.047-0.055mpg) whilst the new one(centrifugal) does 0.25-0.30 liters per 10km(0.065-0.080mpg).
I have the needle lowered as much as i can in the carb and it still gets abit to much fuel so i thought bad carb. switched it out for an other one with same result. ok checked electric if it gets bad spark, and yes a little weak.
changed spark, same result, so switched cdi no better spark.
now i have changed to whole electrical system with no improvement.
I've checked for air-leaks in the intake ans sealed the carb/intake manifold good with flench sealant and o-rings so no air-leaks there.
i have even tried an other exhaust system to see if it was a back pressure issue nothing seams to help.
Anyone having any thoughts???
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