hi there iv just turned 16 and i bought a cheap kymco zx fever brand new £500 so i got it de restricted variator and welded up the exhasut (didnt jet it up straight away cos didnt think it needed it) any way it did about 50-55 on the flat when first done for a couple of weeks started to slow down to like 50 and now about 2 months later its struggling to hold 40 i have jetted it up a couple of weeks ago which didnt really make a difference only thing i can think of is that ts because its currently running with only 5 rollers in it as one fo them smashed. im noi longer using the standard oil injection thing im now premixing any ideas ? would a worn belt cause this ? also iv heard that the exhaust is very restrictive on these is this true ?
Ever heard of a service mate? Stick a new belt, and 6 rollers in there. Is it jetted correctly or have you just stuck any old one in? Why arent you using the oil injection anymore?
how many miles have you done on the bike? it could be that you have been running too lean for too long and damaged the piston.
its currently jetted at 84 is this ok im not using the oil injection thing because v herd that the pump can give up quite easily on these chinese scoots
#1 kymco arent chineese, they are tiwaneese, the oil pump is perfectly good on them #2 not too sure about the jetting, just pull the spark plug out and check the colour. the tip should be coffee brown, white and the bike is is running lean (not big enough jet) or Black/very dark/wet and the jet is too big and giving the bike too much fuel. a 2 stroke will give slightly more power if it is run lean but it will quickly melt the piston crown as the higher the oxygen fuel ratio the hotter the engine will run. With a bigger jet the bike will have a low oxygen to fuel ratio, too much fuel will be put into the cylinder and the bang will be restricted because of the lack of oxygen (hope this makes sense) when you check the plug colour, put your thumb over the plug hole and turn the motor over, it should force your thumb away with the pressure. if not then chances are your compression is down.
well im thinking of getting a new piston and rings kit anyway as its only 20 euros will i need to remove theb arrel or will it squeeze out of the head also will i need a full gasket kit if i do this and do you think it will have damaged the barrel if it was running lean ?
you will need a top gasket set, you need to take the barrel off, its a very simple job on a kymco. it may have marked the barrel if it has got too hot.
where can i get parts for this from only place iv found is racing planet and they only do a complete gasket set whick is nearly as much as a piston and rings set :msn1:
well the jetting must be pretty good the spark plug is a real nicr browny colour bad news for me i think the compression is down i put my thumb over the spark plug hole and it didnt force my thumb off also got new rollers 7g ones new belt but its for the wrong model i thought it was the KCA model but its the zxii model os tht is some money down the drain lol oh well ill save some more money and get the write belt cos i think that is the main problem
it will only force your thumb off if you try to start the bike, and dont put your finger in the hole unless you wana get wacked by the piston, personally i woul;dnt buy a new gasket setid jus be careful removing them. jus get the right belt, fit the new rings assemble carefull and test it out, turn the bike off before the idle jet comes into play and check the colour of the plug
if you can get your finger in there then you got tiny hands as the piston is at least 15mm away from the top of the hole, yeah you do have to spin the engine over reasonably quickly.
ahh that could be why then i was just turning the engine over with my hand using the kickstart might be ok to me it seems to have alot of compression on the kickstart for a 50
as in if it runs you dont need one ? been out on it today at first i was quite supprised it was going really nippy then i was on my way to jet wash it set off home after and it was just rubbish again sat at like 35 there was a little bit of wind but its running really crappy now do you think there just some water on some of the connections or something id hope so other wise something is really broke lol ill let it cool down and dry out then try it later or tomorow this scooter is being really crap so far always breakin or just generally being slow lol
think thats got anything to do with it? there are engines that run on water but these motors just don't...
yup, drain your airbox and dry your filter (don't harm the goldfish that may be living in there though, thats cruel). clean your carb and spray your electrical connectors with WD40, see if this helps scooterd don't like jet washes.
