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Jun 12

Posts: 2

sgrego24585 says:

1999 aprilia rs125 engine noise

Hi there,

I have a 1999 aprilia rs125 which seems to have developed a engine noise/rattle when it is idling however it seems to go when you pull the clutch in.

 I ave recently had a problem were as i put the wrong oil in and it was smoking like a chimney but drained that out and put the right oil in and now ts stopped smoking.

The only other thing i have done recently is adjust the air/fuel mixture screws as the feul was in full and the air pretty much all the way out and someone told me that was wrong so i turned the air back in and release the fuel screw a bit and now it idles nice at about 1k revs. Since doing this i have also lost a lot of hurrible judering at around about 5/6k revs it rids so much better but now i have this noise.

I beleive the bike has the power valve activated and the rav box fitted. all in all its riding lovely just a bit concerned about the rattle. any ideas??

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  • Posted 3 years ago (25 June 2012 18:57)

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Dec 04

Posts: 116

bicster says:


I wouldnt have thought that putting the wrong 2 stroke engine oil in would have caused a rattle that goes when you pull the clutch in as I would have thought it would have been constant, clutch in or out if it was engine related.  I think you need to look in the direction of the clutch plates, clutch basket and gearbox.  I may be very wrong but thats where id be looking.  Good luck at getting it sorted

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Mar 09

Posts: 9034

jaffa90 says:


Welcome sgrego,at least you sound honest with your problem and adjustments (anything else ?),kcmc on here loves two strokes and will have more idea than me.

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Jan 08

Posts: 7745

kcmc says:

Aprilia RS 125 1999

Hi Sgrego24585 and welcome to the site:smile

Must say it just could be a bit of clutch chatter,bit of wear usually not a big problem,when did you last change the gear oil or even check how much is in there?.Think your a very lucky boy running on the wrong oil and getting away with it,in most cases running on the wrong two stroke oil will cause massive detonation resulting in a holed piston.Always try to run on a full synthetic not a mineral oil, semi-synthetic is OK but not ideal,anyway change that gearbox oil, a good light race oil like say Putoline or silkolene,these bike require the best oils,you don't need a seizure now do you:upset: .Good Luck


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Jun 12

Posts: 2

sgrego24585 says:

rs 125

Hi guys thanks for the reply.

Only had the bike about six weeks so i will check the gearbox oil and go from there. Thought it might not be such a big problems as everything works as it should ie selecting gears and stuff. Still cant beleive how much smoke came from the machine for using the wrong oil lol it was everywere even got me pulled by the police. thanks again.

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