classic motorcycle forum

Hi all, I have a question about nozzles in carburetors.

i made my second bike, 2stroke 2 cylinder benelli 250 2c for race.
originally hee has 2  dellorto VHB 24, vith nozzle - 100.

The change about engine is:  no barrel vith chambers for slowmotion air, i got  dellorto NOS, 
instead of serial  exhauster  i got resonant open exhauster per cylinder,
and  expand of intake  channels in cylinders.

So: i take nozzles instead 100, 115,(compenzation for more air) and i dont have power.
i try nozzles 125, 130, 140, 145, and same problem.
my mechanic say  to i need larger carburetors, accurately dellorto VHB 30.

i understand that is bigger, moore soup, and all, but can I  combine something with small vhb 24, and large set of nozzles?

thnx,  Miljenko

If you try find original ignition, you failed. I search dansi for my benelli 2502c, about 3 year all over the internet,  and no result. If you need profi ignition, you can find it at old sell places with old bike parts, and price is about 150 to 250 EURos, I hawe a friend that hawe restauration workshop in Zagreb (Agram), and use them too models like Kreidler, Ziegler, Sever, Morbidelli, and one 250 Aermacchi. That kind of ignition have add vor Rpm.  If you fail find anithing, and must hawe only a spark, and bike to run, i can send you elektrosheme with parts to make your own ignition vor my benelli, it works like old original, and all pieces is about 5-6 Euro.

and if you make yor own ignition like in pic, clever is make cover, and post hoot plastic, for test drive I only isolate elements vith guff tape

P.S.
if you see L2 and L3 is short cyrcuit, but you must connect wires too diferent places, and  I have tvo grounds, that is vith ommether short ( grounds from generator and ground from bobina( highvoltage spoil)) it goes too L2 and L3

if i remember something, I post it

I use online dictionary for some words so if something is not understending, tell me.
before I made my ignition, i $%^&& my self 2 years at internet, motoservises and servisers for electronic and zero points. I vent to Imola in Italy and find all neew or old parts, cilinders, magneto, everiting, but elecronic ignition.
Possible is too make batery ignition vith no magneto, but it needs  lots of vork  and changes in bike, my frend have a workshop for restauration and got lots of parilla, ducati, keidler, ziegler, sever and other, and all juse one same ignition, vith no generator.
Short explenation of my benelli  wiaring diagram:
i have 2 cilinders, witch pistons are in 180 degree diference. i dont have two electronics or two pick ups, i have one pick up and one electronicks, but magneto have two indicator too pick up, and it give two sparks in same time in booth cilinders in one process. one is in upper  point, and other usseles is in down piston point, but in this moment it gives in same time spark in other cylinder where is in upper point (piston)
i can post from my manual wiaring diagram, but is complicated because lots of useless wires for other stuff like lights and other that is not important for generator-capacitor-spoil-spark process.
And i have batery 6V, and is only vor pover and stabilization of lights, you can start bike vith no batery.
Prymary function of ignition is replacement for mechanic     contact breaker which looses 1/6 sparks

Hello from Croatia!
Here is the diagram

Hi everyone! Is enybody makin a electronic ignition vith thiristor  or transistor, I making my one for my benelli 2502c (1976) and have some litle trouble. This Italian part vhose protected by factory vith plastic and unnamed electronics elements, but I still have open up it, making a  sheme, and i cant identify transystor (or thyristor), also have a 6 diods and 1 kapasity. Its simply electronic for two  stroke engine, and i have some material for making ignitions for cars. Is enibody have some electronic diagram, shematic or anything? If not, wen I solve the problem , I have to publish it. Thx for reading this :-D

my benelli 250 have a 32 HP, air cooling  engine, ( 231ccm, 2 stroke, 2cylinder 1976Year) good is i made some preparations for race, if you put vibrant exshaust, you get 10-30 % power. vith factory exshoust it goes about 160 km/h.
Bad is air cooling system, at sommer vith 40 C degree, at 8000 rpm the piston is blick the engine and piston rod is brake it off.
 From mechanical side, gear box is similar too morbidelli. spare parts, I  went too Italy every year in Imola.

sorry, but is too late to say no, I have allready scan from manuel, and I dont know anny other thing to do than publish diagram.  This is for Benelli 250 2c, 1976. Tell if is the same in yor's, and for what do you need it? Are you have a problem vith ignition, or Lights? I'm curious