View Full Version : Odd and fluctuating idle

05-16-2009, 09:19 AM
my 09 has been having some weird idle issues since day one.

sometimes it will idle just fine.......then you pull up to a stop and it will want to idle at like 5000 rpm......then it may decide to idle very very low where it seems it may stall......then again back to normal.

this happens in no particular pattern and seems totally random

Any ideas as to what the issue is?

05-16-2009, 09:34 AM
take to your aprilia garage and get them to sort if its under warranty. If not though, sounds like its running rich on the ideal screw, the air/fuel screw should be at 2 1/2 turns and the ideal should be set when the engine is warm

05-16-2009, 10:21 PM
I turned the idle down a bit
fixed the problem on mine
it's on the right side black plastic screw
turn counterclockwise with hand
might be hidden in the cowl
try it out

06-01-2009, 12:09 PM
Not sure if you figured your issue out, but it actually sounds like the problem a lot of us have had: IE the idle jet is too small. Here is a thread (http://www.apriliaforum.com/forums/showthread.php?t=175427) for going from the stock S35 size to the S45. Seems like a lot of people (me included) have gotten good results with this.

the brit
06-02-2009, 03:28 PM
I have the exact same issue with the 'pulling up to a red light and idling at 5k'. I spoke to my dealer before the warranty was up and will get it looked at during it's first service.

Mine's never low though, just gets stuck at 5k until I let the clutch out slightly to bring it back down.

06-02-2009, 04:48 PM
thats sucking fare too much fuel in "the brit". Ether that or its running lean

the brit
06-03-2009, 11:04 AM
thats sucking fare too much fuel in "the brit". Ether that or its running lean

Yup, I can guarantee that it's either rich, lean (or indeed Stoich.) :rolleyes:


06-03-2009, 07:21 PM
it sounds weird, but when it runs lean, it revs up on its own. But it can suck in too much fuel which acts like its revving.

06-04-2009, 10:31 AM
Not returning to idle straight away once revved is a sign of a lean setup