I have a 2015 nsc50 with 2400 miles on it. I've had it since 300 miles. Always changed oil every 500, looked after it generally. Recently its been 3-5 mph slower on certain hills and acceleration is worse. Also pulling away its bogging down, and at idle ( when using the 110cdi idle is lower ) its a bit uneven. With the original 50 cdi the idle is always higher, and it can hold that idle ok. When I pull away it feels like its in too high a gear, the engine never spins up much even with very stiff clutch shoes. Heres what I've done so far: Put on new polini belt. Scooter is actually slower with this , guess it must be tight being new? Reset ECU. Bike is EFI so no carb to worry about. Tried lighter rollers than the set which has been fine for ages. Tried heavier rollers Tried light and heavy contra springs Used polini, malossi and standard variators. Standard variator does give a bit more revs setting off than the 2 aftermarket ones but is restricted for top speed. Took apart rear pulley cleaned and greased. Feels like it moves pretty well, needs a little bit of encouragment to move but it always has I think. Didn't see any wear point in the grooves. New spark plug Check air filter clean Checked for exhaust leak Changed rear gear oil Check valve clearances, all set to exactly factory spec of .20mm and didn't have to change them Its had a few tanks of petrol so its not that. Used both 110cdi which revs higher and gives more power ( my normal setup ) and back to original 50cdi. I'm pretty stuck where to go from here. I guess I'll do a compression test but surely it can't be down after 2400 miles. It has been revving higher than standard with the 110cdi but not that bad. Any ideas would be appreciated!!!
Brakes and tyre pressures are fine. Can a stator thats not producing enough voltage affect engine power?
Hmm youd think the ECU either works or doesnt though, its just gutless up hills. Fine on flat and downhill. I did a compression test and got only 90psi, the workshop manual says just over 200psi !! Im not 100% confident of the tester as its not mine but my neighbours and it has an airline style connector which I hear isnt that best ... but saying that I didnt hear any air escaping. I think it either has a bent valve, or damaged piston , rings, cylinder. Might have to open up my first 4t engine.
not that I’ve noticed but think the rings , cylinder or piston are worn out. Some debris must have done it as it’s only done 2500 miles. Its getting worse fast now. The exhaust smells oily and there’s strong blow by coming out the crankcase breather pipe. I’m trying to find a low mileage engine to replace. Very annoying mines gone at such low mileage.
Have a look behind your spring at your air box. There's a little rubber mud flap that protects the engine from splatter. There's a design issue where this flap rubs a hole in the air box and let's crud into the intake. It is very odd that your engine as started to fail at such low mileage. You have done the 110cdi mod just like I did and it been fine with me for around 9000 miles sofar. Am a bit of a chunky bloke so the main thing that caused me the most hassle was the verio weights I tried lots of combos even taking the dremel to a few sets to finer tune them finally I went with a polini kit and 3.2gram rollers.
