I had an oil leak from the oil tank in my mc21, also had a problem where the bike doesnt accelerate smoothly, instead at higher revs it 'stutters' and loses power.

I took it to a bike mechanic in Melbourne to look at it, he said it was running too rich, he fixed the oil leak, replaced the spark plug and gave it a 'tune' to make it run leaner. Cost me close to $200au.

Now i notice a problem that when i start riding it, i hear 'pops' now and then from the engine and it loses power for a second. After 5 minutes of riding this issue disapears. However i still have the problem where it wont accelerate smoothly if i gun it, just accelerates smoothly for a bit and then stutters, and sometimes stutters at low revs also.

Anyone know what the issues could be, so when i take it back to the mechanic i can have some idea what im talking about.

Thanks.

did your mechanic clean the air filter ?

I do not know.

Is the bike still restricted? Have you done a plug chop since the bike came back? My bike is in good tune buti also get what maybe could be popping noise around 7 - 8 k just before she comes on!!!!

Have a look at the Tunning section to find out if you bike is restricted first, Then look at the plugs!! if all is well take it for another run and do a plug chop!!! then come back here and let us know what you find...

Bike is derestricted. Sorry you will have to tell me what a plug chop is . Although the mechanic did put a new spark plug in.

A good way to tell if the bike is fueling well is to do a plug chop, Before you do this check the plugs while cold before you start, if they are golden brown, (not black or grey) then take it for a run, Take the tools you need to take a plug out, get the bike warm, find a nice open SAFE road and wind her up, near the top end of the rev range hold it for a few seconds, then at the same time pull the clutch in, and hit the kill switch......... Bring the bike to a stand still and check the plugs, this will give you an idea of how the bike is running at the upper end of the rev range..... Again if its grey/white = lean, black and sticky = rich, Golden brown is okay... BUT i stress look at the plugs before you go out as they may already indicate how its running!!!!

So its derestricted, dose it have ANY other non standard parts?

Oh and make sure you have the correct plugs in!! again look on this site (spec's page) for the correct type of plug!