Dellorto sha 14.12 vs 12.12

Hello there!

I have a bit of a conundrum. I have just finished restoring a 1989 Tempo Avanti with the Minarelli C2 pedal engine. The moped came with a sha 12.12 that shat itself (floater dead, seals dry, the whole lot).

Now the thing is that the manual says that it should come with a sha 14.12 and I suspect that someone put the 12.12 on there at some point in the mopeds colorful past. Put it on there for shits and giggles I assume.

Since Im in Norway and the whole quarantine thing is fucking with international shipping something fierce I have a choice:

1) Get a new sha 12.12 for cheap like tomorrow from the store and be done with it.

2) Source a 14.12 from germany and sit on a chair rocking back and fourth until it arrives.

(Seal kit and new floats are difficult to come by here, so I might as well go for a whole carb while im at it).

So my question is this: How different is the 14.12 from the 12.12? Will the difference have any long term effects? The 12.12 thats on there seems to have been there for a while but it was also parked for 10 years so the gods only know if it ever ran properly in the first place.

Thank you kindly in advance.

Re: Dellorto sha 14.12 vs 12.12

So most Vespas came stock with 12.12s. If you replace it with a 13.13 you gain noticeable speed. Replacing with a 14.12 should see a similar gain

Re: Dellorto sha 14.12 vs 12.12

Ľ̷̝̽͒i̶̛̼͑͠ȁ̸̧̛̽m̵̻̟̯̀̅ ̷͎̙̽̊F̶̲̺͑̓ F /

I have a new 14.12 and I have some jets and could send you the carb and about the right jet for the bike for fairly cheap

Re: Dellorto sha 14.12 vs 12.12

Dirty30 Dillon /

The Vespa series SHA and Standard SHA do not simply interchange, so post a photo of what you have on the bike.

If someone has modified a Vespa SHA to fit, I'd say replace with a standard SHA 15.15 just to future-proof any other upgrades you may make as well.

Re: Dellorto sha 14.12 vs 12.12

roy jongejan /

Why a 15.15? Spend some time and find yourself a 16.16 if you're gonna make it future proof.

As for SHA spare parts, i found that the cheap replica's are great donors to rebuild an original.

Re: Dellorto sha 14.12 vs 12.12

> roy jongejan Wrote:

> -------------------------------------------------------

> Why a 15.15? Spend some time and find yourself a 16.16 if you're gonna

> make it future proof.

>

> As for SHA spare parts, i found that the cheap replica's are great

> donors to rebuild an original.

Cause 16.16s suck. There is no performance gain for a moped over a 15.15 and you get worse gas mileage.

Re: Dellorto sha 14.12 vs 12.12

Dirty30 Dillon /

> roy jongejan Wrote:

> -------------------------------------------------------

> Why a 15.15? Spend some time and find yourself a 16.16 if you're gonna

> make it future proof.

>

> As for SHA spare parts, i found that the cheap replica's are great

> donors to rebuild an original.

16.16's are notoriously more finnicky with tuning because the Venturi diameter is at the limits of the usable slide width, aka less sealing surface is between the slide and body.

There's a reason why people don't drill their SHAs out to 16mm, and the max is around the 15.4~mm offered by a 1/2" bit

Re: Dellorto sha 14.12 vs 12.12

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> The Vespa series SHA and Standard SHA do not simply interchange, so post

> a photo of what you have on the bike.

>

> If someone has modified a Vespa SHA to fit, I'd say replace with a

> standard SHA 15.15 just to future-proof any other upgrades you may make

> as well.

Im a bit far away from the moped currently but here is a picture of the engine when it was out. The "clamp" says 12 12 on it. (edited)

INGIN.png

Re: Dellorto sha 14.12 vs 12.12

Dave Thacker /

So, I understand a 15.15 is 15mm throat, a 12.12 is 12mm throat. What is a 14.12? I've been wondering what first second number mean?

Re: Dellorto sha 14.12 vs 12.12

The 14/12 and 12/12 are both 12mm at the venturi. I can't imagine there is a noticeable performance difference between the two.

Re: Dellorto sha 14.12 vs 12.12

Dirty30 Dillon /

That's a Vespa SHA, which is different from a standard SHA, which is what a 14.12 would be. Different body size.

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