Dellorto Pumper Carbs


XS650 Addict
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Hi, kind of thought this link could come in handy for anyone looking into the Dellorto carbs. Ive got myself a pair teamed up with my 750 bigbore and searched around to get some more details about the carbs that I have.

Found this page wich is nice with alot of information related to the Dellorto carbs.

Dellorto Carbs

I have mine jetted and dyno tested for my engine, once I have the specs ill add the info to the thread, for others to see as a potential baseline.:bike:
What size carbs are you using? Also the inlet manifolds will alter the jetting considerably, I went from 148 to 132 mains just from changing the manifolds
Ok, so these are my settings... Remember its only suitable as a baseline.

Subject 36mm Delorto Carbs with accelerator pumps:
Application - Yamaha XS650 Vertical Twin
Casting Mark (Carb for LH Side) - PHF 36 (DS1)
Casting Mark (Carb for RH Side) - PHF 36 (DD1)
Float bowl Mark - R 4676
Slide - 60/3
Slide Spring - Lightest Tension Spring
Slide Needle - K5 (clip in middle groove)
Accelerator Pump Nozzle - # 33
Main Jet - # 142
Needle Jet - AB265
Pilot Jet - # 65
Fuel pickup AC pump - No ID # (ball bearing valve)
Choke Jet - # 70
Pfbat Valve - # 300
Plastic Float - 74501
Intake (Head side) casting mark - D3 Note:Head side OD is 44mm.
Mixture Screw Setting - 3 turns out (- 1/16)
Choke actuation - Lever (flip choke type system)
Velocity Stack - Plastic Delorto type, threaded, No screen, 48mm x 30mm Long
Carb Top Adjuster - 110 degree bendtype
Carb Top - Standard
Casting Mark (Carb for RH Side) - PHF 36 (DD1)
Float bowl Mark - R 4677

Hope it can come in handy :thumbsup: