Adjust Vespa carburetor

Adjust the carburetor on the Vespa - that's how it works

VESPA - CARBURETOR

The Choice of carburetor size has a significant influence on the performance and characteristics of the engine. Useful carburetor sizes range in
the range from 19 mm to 35 mm.
In addition to the empirical values ​​from other screwdrivers, there is also the possibility of a formula or a table to determine the required
Refer to the size of the carburetor. The required size of the carburetor is largely determined by the speed and the displacement. So results
the following formula:

d = carburettor diameter (mm) Vh = displacement (cylinder, liter)
n = speed max.power (1 / min.) k = factor (see text)

The factor k is an empirical factor. for Scooter motors lone lies with the factor 0.7 – 0.8 quite well.

VESPA · ADJUST THE CARBURETOR

Most engine damage is not caused by mechanical problems, but by poorly tuned engines. Above all, they are critical here
all questions relating to compression and pinch edge, as well as ignition and carburetor settings. Unfortunately, the correct carburetor setup is not the case
easy to find like the correct ignition timing. In addition, the result cannot be checked as easily as with the ignition timing and the Ignition gun the case is.

We would like to help you here that you still get your carburetor well tuned. Correct jets are essential for the engine to survive.
There is no city or motorway vote, just one: the right one. Unfortunately, this can only be experienced individually for each engine. Our Spray tips table should help you to find an initial value from which you can then proceed to the one for your individual engine suitable spraying can work towards it. At first glance, carburetors may seem complicated, but with a little theory and practice the whole procedure isn't that wild anymore.

CANDLE IMAGE

One should keep in mind that with today's modern synthetic oils the spark plug pattern only provides imprecise information about the state of the combustion
gives away. Especially with very high-quality candles (Nippon Denso), which are of course still in the middle of the fresh gas purging flow, show as good as
no more deposits. As a rough indicator, however, the candle can of course be unscrewed after driving at full throttle (directly at full throttle ignition
switch off and pull the clutch!).

A grayish / snow-white candle

This picture of the candle indicates a burning that is far too hot. The engine should not be operated like this!

A black spark plug

A black sooty or oily candle indicates one fat vote of the carburetor, too high an oil content or, in general, a not optimal combustion.

SPRAYING TIPS

So that you don't have to start completely from scratch when setting up your carburetor, we have put together a small overview of well-functioning carburetor setups. You should understand it as a guideto get the engine running. Then you should make it fatter from area to area and then jet down. No guarantee!

Cylinder carburetor main jet auxiliary jet mixing tube needle
Vespa Smallframe 75 cc SHB 16/10 55-60
Vespa Smallframe 75 cc SHB 16/16 68-75
Vespa Smallframe 75 cc SHB 19/19 75-82
Vespa Smallframe 85 cc SHB 19/19 75-82
Vespa Smallframe 110 cc SHB 19/19 82-88
Polini 130 PHBL 24/25 85-98
DR 133 SHB 19/19 85-90
Malossi 136 PHBL 24/25 98-115
DR 135 SI 20/20 102 (TÜV)
DR 135 SI 24/24 112-115
DR 177 SI 24/24 108-112
DR 177 PHBH 30 112-118
DR 177 PHBH 30 105-120 50-60 AV262 X2
Malossi 139 SI 20/20 112 (MOT)
Malossi 139 SI 24/24 100-110
Malossi 139SI 24/24 105-118 52/140 160BE3
Malossi 166 SI 24/24 125-130
Malossi 166 PHBH 30 125-135
Malossi 166 TMX 30 350 17,5 hrs. hours.
Malossi 210 Dell'Orto 28 128-138 50-56 AV266
Malossi 210 Mikuni 30 300-330 20-27,5 fixed 5EL68
Malossi 210 PHBH 30 135-148 55 AV264 X3 or X7
Malossi 210 TMX 30 280-320 std. hours. hours.
Malossi 210 TMX 30 240-350 30-22,5 622-N-9 5EL68
Polini 177 SI 24/24 120-125
Polini 177 PHBH 30 125-130
Polini 177 PHBH 30 125-150 50-55 AV262 X2
Polini 177 Dell'Orto 30 120-128 48-55 AV264-266
Polini 207 SI 24/24 120-138 55 / 160-50 / 140 BE3
Pinasco 177 SI 20/20 108-112
Pinasco 177 SI 24/24 118-122
Pinasco 177SI 24/24 125 55/100 BE3
Pinasco 177 Dell'Orto 28 118-125 48-55 AV264-266
Pinasco 177 PHBH 30 135-160 55 AV266 X2
Pinasco 177 PHBH 30 138-150 52-55 AV262 X3
Pinasco 213 SI 24/24 125-130 55/160 or 52/140 BE3 190 or 160
T5 Polini 152 SI 24/24 112-120
T5 Polini 152 SI 24/24 118 50/100 BE4
T5 Polini 152 PHBH 30 120-130
T5 Malossi 172 SI 24/24 115-120
T5 Malossi 172 SI 24/24 125-138 50/100 BE3 / BE4
T5 Malossi 172 PHBH 30 125-130
T5 Malossi 172 TMX 30 (membrane) 260-290 17,5-22,5 fixed 5EL68