Tuning Tips against OVERHEATHING?

Hi to all Vespa gurus!

i am a complete Vespa newbe and run into frequent overheathing problems :frowning:

Is there any way to improve my Vespa performance to minimise overheathing ?

How do you guys deal with that annoying problem?

any tips links highly appreciated,

thanks in advance

dimitri

Vespa 50/S 1967 with ( kit 75cc) 19mm Delā€™Horto Carburetor


anyone?

hello,

many things make the engine temperature to go higher then should.

Not correct timing, too advanced.

Carb set up too lean

Spark plug not of the correct grade.

the set up is really important. Too many people just mount the kit and don't even bother to change a plug with one of the correct grade, and don't change carb setting and don't even know that they should check the timing as well.

www.curareracing.com

Hi Curare, thanks for your reply.
i do agree with you about the proper tuning.
i am a total Vespa beginner and no one has a clear information
on howto tune the engine correct timing and a carburetor as well as the ignition.
I have an original Vespa 50S 1967 50cc engine with 4 gears
the Piston ring is broke - has a non-standard size 43mm - cannot find in any shop :frowning:
So i desided to change the whole Cylinder and going forĀ  a 115cc Polini Kit.
I have already a Polini raicing exaust and a Polini 19mm carburetor.

will my engine take this Kit without problems ?
Will it improve the torque and the driving up the heels - speed is no importance to me?

Where can i find an info on a proper tuning my smallframeĀ  Vespa 50S ?

What is the most populare - busy smallframe Vespa forum at the moment?

thanks in advance

jazzroom

P.S. checked your site - you are a real Vespa conasseur - bravo!



[quote user=ā€žcurareā€œ]

hello,

many things make the engine temperature to go higher then should.

Not correct timing, too advanced.

Carb set up too lean

Spark plug not of the correct grade.

the set up is really important. Too many people just mount the kit and don't even bother to change a plug with one of the correct grade, and don't change carb setting and don't even know that they should check the timing as well.

www.curareracing.com

[/quote]

Thanks for the links and tips Curare.
unfortunately i have already bought the 115cc pollini Kit for my 1967 50 Sā€¦
and you were right - the installation was not as easy as i thought,!!! ---------

Me and my friend forced the cylinder onto th piston maybe a bit to much ā€¦
cause the Motor didnt want to fire up.

Brought my Vespa to a pro-Vespa-mechanic finally.
He opened up my engine and told me that the oil seals were worned out and many other little things inside the engine need a replacementā€¦ :frowning:
On top of that he told me that the piston was damaged by me during the Kit installation ā€¦ :frowning:

Now he is busy with a complete engine rebuilt with a bigger transmition and a new crankshaftĀ  to support 115 -125 cc Kitsā€¦

It all started with a broken piston ring ā€¦ and nowā€¦

I am in a big troubleĀ  - financially ā€¦ :frowning:

but if i will get my engine completely redone i guess my Vespa will run smoothly for yearsā€¦

hopefully ?

P.S. just subscribed to an English speaking forum you suggested, thanks

hello,

the busiest smallframe forum at the moment is www.et3.it, but is in italian so can be a problem if you don't know the language.

You could post also to http://davedaniel.proboards91.com/Ā is fairly new but growing. It is in english.

For your question. get a polini 102 instead of the 115. The 115 is less forgiving about set up mistakes. The 102 works well with 19/19 carb. You should upgear with a 22/63 or polini 21/62. this last one is alu made so you have to mount polini alu clutch discs with.

When you have the stuff and ready to mount ask for the set up.

Ā 

www.curareracing.com

Hi to all,

Finally my Vespa 50S is back from a complete engine rebuilt !
it was a very expencive repairā€¦ :(Ā  butĀ  engine was a ruin before , so i am happy.

new bigger crankshaft bigger transmission , all new bearings and all cables and electrics, etc. with added reed-valve for 19/19 carburetor. Pollini 115 cc kit, Polini racing exaust.

The Vespa mechanic made the space inside the engine case bigger and
made the hole going to sylinder from the engine bigger as well.

Now my vespa 50S ( 115cc pollini kit) feels and sounds much different than before.
Driving it a week already , havent really pushed it to full speed yet
and havenā€™t had any overheathing yet ā€¦
fingers crossed :wink:


Vespa mechanic told me i would need a bigger carburetor - 24 maybe with a reed valve,
or to adapt my reed valve with a peace of rubber to the 24 oneā€¦

Vespa drives well, maybe accelerates a bit slow ā€¦

What are the benefits of a bigger carburetor for me and drawbacks?

Witch 24 carburetorĀ  would you suggest?

There is not enough current to support front and the back light at the same time,
mechanic put the halogeen lamp in front - niceā€¦ but the back light is almost invisible now :frowning:

How to adapt my Electrics to 12V the cheap and easy way?