New 20 ounce tumblers available now! Forum donation credit with purchase. https://www.wildguzzi.com/Products/products.htm#Tumbler
PS*****Saw the trouble shooting post after I posted*****Yes I did do the google search. Read everything the search returned on carb sync and the PHF 36 A-B DD, Lean burn, shrouded- un shrouded, Euro. US, German variations. All very informative as well as entertaining.That spurred me to look at choke settings.Paul
Good idea. Make sure you have some slack in the choke cables, and the little rubber gizmos (technical term) in the plungers are in good shape.
Check float levels and needle valve. After all these years and miles, I had a needle come apart. Spent days trying to fix electrical issues.
If I remember correctly, which may be unlikely......... My phf carbs giave me trouble on a cal 111. The issue came down to a float needle. Unlike the vhb needles, the phf are two parts with a movement to them....mine was intermittent-ingly not moving, making the float........not. Isn't there a tiny spring inside the float needle?WAG....for free, so it's worth that.....good luck!
You are correct!!! The PHF needle has a spring inside. I did just put in new on both carbs. Also adjusted the floats to within spec. When done I checked the movement and it was free and easy. I will check again just in case on assembly it got sticky.ThanksPaul
I have similar carbs on the Le Mans III. Over the past few years, I have replaced about 4 needle valves in the PHF 36's. Not sure if it's from the quality of gas we have in Pa., or they just wear out.
I have Dellorto PHF 36 on my Laverda and they were stock on the 77 Le Mans I just sold. The set on the Le Mans were clean and after a long ultrasonic bath they functioned fine. The ones on my Laverda will not respond to hours of ultrasonic cleaning and the idle is intermittent and they stumble. I have given up on saving them and am ordering a new pair from Columbia Car and Cycle in Canada through Wolfgang Haerter he can beat the price of a similar set on Ebay out of the USA and jet them properly as well as supply manifolds (new Dellorto manifolds will not fit the old style). I replaced every internal brass part on the Laverda set and still they won't run correct, plus the wear between the body and slide can not be rectified without sleaving and new carbs are cheaper than fixing the old set.Wolfgang has been servicing Dellorto's for over 30 years and has had several of the PHF carbs that have blocked pilot jet passages that will not clear even with ultrasonic cleaning. He tells me he has even cut apart a PHF 36 to find the blockages and reports the tiny pilot passage ahs blocked more form oxidation than anything else and they are often irreparable. Nothing more annoying than investing a lot of money in a restoration to fight old worn out carbs.
Nothing more annoying than investing a lot of money in a restoration to fight old worn out carbs.
This. When I was putting the Aero engine together, I thought 36s would be about right. Milich said he'd sell me a set of the Goddess only knows how used ones for $400. The Kid got me a set of new ones for a little over $500. Guess which way I went? Naturally, it started right up, and I haven't had the first issue in over 11K miles now.
Remaining "exactly the same" on both sides at all throttle openings and engine speed should not be the goal. Close is acceptable. How close, there is a specification somewhere. Maybe someone can share it. 1 pound of mercury indifference is acceptable on a set of Mikuni's per their tuning guide. You did not mention how much they get out of balance.
There's no guarantee that both carb slides are identical, especially the slide cutaway which has an effect on slow speed airflow. Remove both slides and compare them side by side...I have found that sometimes the slide cutaway needs a slight re profile with a file so they both match...It's been my experience that even air flow at small throttle openings makes V twins run nicer in town... You may also want to try an airflow meter rather than trying to balance manifold pressure...I use this one on two cylinder bikes.. But it may or may not fit on a Guzzi situation? I use this one made in Germany for about 50 bucks on Ebay...Try to avoid the Chinese knockoff...
Carburetors primarily meter fuel in response to air flow.... Compare the slide cutaways by placing the slides together .Take measurements and or make a template...Slight differences do affect air flow and if you feel up to it, use a half round file to make them identical as possible...A bigger cutaway leans the low speed mixture so thread carefully and only match the small cutaway to the larger one...If they are the same, then look elsewhere...