Aprilia rs 125 jetting??

[gedi1305]

Hi
I have a aprilia rs 125 2008
Parts fitted:
Arrow exhaust system
Pipercross panel air filter
28mm standard carb

At the moment its running on a 140 jet but ive been told thats wayy to low.
So if anyone can help that would be great
Thanks

[Timmeh]

Kickstart has already given you the answer, you should be using a 180 main jet.
____________________
GSXR400 x2 | '94 RVF400 | '93 TZR125 4DL (again)
20:22:30 BLUEX5: i would love to be forced to undergo a**l plugging with different sizes
20:48:18 Temeluchus: comp you hunk of smouldering homos3x you

[gedi1305]

Ye
But that was just for the arrow system
I was wondering if having a pipercross airfilter you would nee even bigger than a 180

[Timmeh]

Fuck knows, there's isn't a magic formula we can apply to get your fuelling right. That's what dyno runs are for.

Buy a bunch of jets starting at 180 going up in 5s to about 220, and a colourtune.

Keep jetting up until the colourtune starts to look right.

Take out for a spin and keep doing plug chops to confirm fuelling state.

Bear in mind that you're only changing the main jet.

If you want to do it properly, book it for a day on the dyno. Which will probably work out cheaper in the long run than you keep replacing pistons.
____________________
GSXR400 x2 | '94 RVF400 | '93 TZR125 4DL (again)
20:22:30 BLUEX5: i would love to be forced to undergo a**l plugging with different sizes
20:48:18 Temeluchus: comp you hunk of smouldering homos3x you

[gedi1305]

Yeah
Got aload of jets on order and booked a dyno for the 7th august
I will let you know how it goes
Thanks

[Kickstart]

Hi

Start rich and work down. Rich is safer than lean.

Colourtune will be pretty useless for the main jet though. Not sure I would want my head close enough to a glass spark plug to see through it when using full throttle.

All the best

Keith
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