Post by jfcpeng on Nov 21, 2015 23:19:29 GMT -5
Hi, new on this board but I felt this is worth pasting.
Up until about 37mph the rolling drag exceeds wind drag. To get to over 37mph quickly, it helps to reduce rolling drag.
1) Inflate tyres to a higher pressure and check tyre is actually round.
2) Loosen front axle nut and watch wheel spins longer.
The spacer between wheel bearings is usually a millimetre shorter than best so all bearing spacers fit all wheels on the production line. As you tighten axles, the two inner races are misaligned to outer races. Similarly loosen wheel axle and bottom fork and let return, then measure space between fork leg and axle spacer with all free play on one side of wheel. Again the axle spacers are all made a mm short so that they fit every bike. Because the fork travel is so short, bending forks inwards 1mm is significant in deforming axle and forks when axle nut is tight. If you dress off the spacer that sits in the seal a few thou, add Teflon lube, tolerance out the spacers to ensure wheel bearings are true, replace wheel bearings with C4 frictionless seal type, sand off high spots inside brake drum often (I have a Scoopy 50) and high spots on brake pads often (the glazed patches) and make sure there is no brake drag when not using brakes.
I put a 1mm washer on axle and there was a huge difference when you spin wheel and wait, instantly.
50cc and 2, 3 or 4 hp is not very much. A person can do 1hp for short spells and a rusty bike chain and a dragging brake on a bicycle makes a huge difference. Bicycles run 110psi in tyres 1/4' wide!
BTW Has anyone removed the air fan from the flywheel and fitted a switching battery powered fan to the radiator? I suspect the crank flywheel fan is to impede acceleration at the crank end so belts don't get abused from rapid accelerations at crank. I am sure putting a thermo fan on the radiator without the crank fan would provide quite a few hp at 9000rpm but on a hot day up a hill the new thermo switch computer fan on the radiator might struggle.
After 37mph wind drag goes up very quickly and rolling drag creeps up but from 0 to 37mph rolling drag is very significant to MPH and MPG.
Have fun with the thoughts above. I am 60yo!
BTW A good racing port job on a C50 Honda I had years ago gave slightly better acceleration, slightly higher top end, 40mph at half throttle not full throttle and lots better economy. Ruckus might be the same. Using thin oil also made a huge difference, change it often and sell the bike when you see metal specks in the oil pan residues (not likely on a Ruckus as gearbox is not part of motor!