As said before, exh blockage sounds possible. Has this with the other half's car. Turned out the internals of the cat conv. came loose and blocked the exhaust.
The rattle after 15 mph before it cuts out could be pinking, week fuel mixture, all symptoms could indicate a lack of fuel problem. Steve PS you say it is not as bad when cold, the ecu will be giving it more fuel when cold.
Right a compression check is in order first to establish the health of the cylinder and piston, if no sounds are present then we can say the health of the engine is good, also given that it is a Honda then chances are it is ok. We need to see if it is valve related as the popping you say leads me to the upper cylinder first. What milage is on it Lucas and when was it serviced please?
15.5k and with maintenance schedule. At 15k I have changed oil, air filter plus now belt and rollers.
this pic reminds me of when some builders in Kingston put the parking wardens moped in the skip View attachment 21496 [/QUOTE]
I will pick it up next week. Will ask if he done all those (hope he did being a scooter shop). If not will test and see what I come up with.
Agree with final_edition - sounds like fuel starvation to me. Check filler cap, clean all breather hole/passages and then check the fuel line from fuel tank to carb Good luck
ok so is this a 2 stroke or a 4 stroke engine so as said could be incorrect mixture being delivered so ........blocked injector ? blockage in exhaust system ie carbon build up if 2 stroke also daft thought if 4 stroke valve clearances could affect running when warmed up longshot but hey.......
So picked it up today. Wanted to do compression test but cannot find my tester. Spark plug is white like snowman!! With open fuel tank I can ride 30-40mph. When I reach that it starts being rattly and looses power. I tried to ride through it and pinned throttle full. Bike was running rough but neither was it accelerating nor slow g down. From standstill i can whack full throttle and for 2s it is good then it starts bogging down. Honestly looks to me like fuel issue now.
sounds a bit like an air leak ? ok so 2 stroke white plug = lean mixture rattle from engine possible main crank seals and bearings pulling air in at crank would lean mixture hard to tell without actually looking at bike could check behind flywheel to see if oily damp from leaking seal
It is not a 2 stroke, it's a 4 stroke injected. Apparently it does not have a fly wheel just stator that acts as one plus as timing wheel. Finm forgot about that, will try tomorrow but exhaust gets blocked with unburned oil on 2 stroked only? Also that would make the mixture rich not lean.
Johnboy, I have no idea how that engine is built, I guess flywheel (stator) would be on left side behind clutch/rollers as looking at it that is the only place. Both clutch and rollers were changed and nothing abnormal was noticed.
Lucas Well worth taking Finm's advice, and disconnect the silencer temporarily to see if that makes any improvement. I would also suspect possible inadequate fuel delivery. Possible rusty tank clogging fuel tap and restricting fuel flow! Can you disconnect fuel line anywhere to check fuel flow?
ok luca not familiar with this engine difficult to diagnose over the net lol so many different moped engines so many faults give same symptoms ok so 4 stroke thinking cap on !