A simple equation for figuring you main jet is to multiply dia of carb by 5 and then multiply buy 0.85 for stock 0.9 for bike with sports airfilter fitted 0.95 for airfilter and exhaust .
28 x 5 x any of 0.85 - 0.90 - 0.95
3. float
4. atomiser
5. idle tube / pilot jet < same thing
7. needle valve and seat
8.main jet anti surge washer
air fuel is the angled screw towards the air box and is a air screw (not the one with the spring on thats the idle screw)
out =more air to fuel
in = less air to fuel
float height set at 14mm dellorto suggest 11 mm i ran 14mm tho
Aprilia rs125 34mm carb strip down video
The purpose of the carburettor is to provide your engine with the correct ratio of fuel and air. Although the carburettor can’t provide the ideal mixture at all loads, the different parts of the carburettor work to try and create this ideal mixture for proper combustion.
see more Aprilia RS 125 posts here
Aprilia rs125 carb jetting 34mm and 28mm
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Aprilia rs125 28mm carb on Ebay UK here |
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Aprilia rs125 carb jets on Ebay Uk here |
Dellorto PHBH28BD standard
you do not need to re-jet for derestriction but its always advisable after any change to do a plug chop test to test combustion conditions , this will give a clear indication of the jetting and running condition inside the cylinder , also its recommended to increase jets size 5 points for any sports airfilter or exhaust fitted and again do the plug chop test to ensure correct running conditions this is a good habit to get into after doing any work on your bike that may after fuelling .
starter jet 70
main jet 120
pilot jet 62
slide needle valve bn266
float needle valve 250
1. choke jet
2. main jet 3. float
4. atomiser
5. idle tube / pilot jet < same thing
7. needle valve and seat
8.main jet anti surge washer
air fuel is the angled screw towards the air box and is a air screw (not the one with the spring on thats the idle screw)
out =more air to fuel
in = less air to fuel
float height set at 14mm dellorto suggest 11 mm i ran 14mm tho
155 main
36 idle jet
1.5 turns out on the air screw
60 choke jet
k57 needle top notch
app 266 needle jet / atomiser
Aprilia rs125 34mm carb strip down video
The purpose of the carburettor is to provide your engine with the correct ratio of fuel and air. Although the carburettor can’t provide the ideal mixture at all loads, the different parts of the carburettor work to try and create this ideal mixture for proper combustion.
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Aprilia rs125 28mm carb see them for sale on Ebay UK |
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| You could just dump it all in your ultrasonic cleaner , get one they are excellent  |
Great post.
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