Author Topic: V65 PHBH30 jetting  (Read 3074 times)

Offline smallblockofcheese

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V65 PHBH30 jetting
« on: June 06, 2019, 05:49:09 PM »
I set the PHBH30 (US spec) carbs on my wife's '84 V65SP to guzziology specs and now its running piggy rich across the board. The idle circuit is so rich i don't need to use the chokes to start from cold and the bike will die if i crack the throttle wide open (from idle, in neutral).

 I was just curious if anyone would care to share their jetting for me (and potentially others?) to reference and compare.

Guzziology specs:
#40 slide
#40 idle jet
X8 needle (2nd notch from top)
accelerator pump removed
needle jet oversized with #36 bit
non-EPA mixture screw

Her bike has the stock airbox. Elevation 300'

Ive tried lowering the needles, putting the EPA mixture screw and leaner #50 slides back in, but the plugs still show a heavy carbon buildup.
Im thinking I will try #35 idle jets but i was just curious where others ended up.

Thanks in advance.

Offline SED

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Re: V65 PHBH30 jetting
« Reply #1 on: June 06, 2019, 08:46:04 PM »
I did that mod and the 650 runs way better than the old 500 did with stock carbs.  And gets about 50 mpg.  I've been very happy with it.

This is what I have:

Atomizers (needle jets) drilled by #36 bit
needles = x-8, clip in top notch
main jets = 105
idle jets = 40, roughly 2 turns out on idle screws
choke jets = 60
slides = 40
floats = 11 gram #90101, 25mm float level.
needles and main jets are new.

Stock airbox - sea level, but rides up to 4,000' or so.

Perhaps your choke cables are hanging up?  If the end of the cable casing comes out of its recess it can hold the choke on.

Let us know what you find!
« Last Edit: June 06, 2019, 10:52:56 PM by SED »
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Offline Diploman

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Re: V65 PHBH30 jetting
« Reply #2 on: June 07, 2019, 01:30:35 PM »
I recently converted my V50II from US EPA to Euro spec jetting on its VHBZ24 carbs.  As per Guzziology, this change involves switching the OE E43 needles to E2, and the OE 258 needle jets to 260. The bike now runs noticeably stronger at mid-to-upper throttle, but has a stumble just off idle.  I have improved the situation somewhat by fiddling with the idbalance between idle slide and idle jet adjustments, but it is still not entirely satisfactory.  Clearly, the mixture is rich transitioning from idle to mid-throttle. 

I think the next step may be lowering the needles from Guzziology-recommended mid notch to top notch, as the OP has tried on his V65.  This is not a big problem but it affects the engine's flexibility/drivability, so if I can't correct it I may go back to the OE USA needles/jets.  That would be a shame, because I really like the way it runs at higher throttle settings.
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Offline jacksonracingcomau

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Re: V65 PHBH30 jetting
« Reply #3 on: June 07, 2019, 09:34:49 PM »
 not quite apples but my v65 lario (same carbs )was stupid rich at idle even with#35 pilots. Have #30’s in it now, smallest supplier had.
At least it now needs chokes to start but will try smaller when I get some

Offline smallblockofcheese

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Re: V65 PHBH30 jetting
« Reply #4 on: June 13, 2019, 04:59:48 PM »
Thank you for the replies. I ordered some 35 idle jets and got those in today. Doesnt seem to have made much difference. Still dont need the chokes.

Where exactly does the atomizer come into play? Im wondering if maybe using the #36 drill bit took things too far. I cant lower the needle any further so i guess the next step is to either try replacing the atomizers or try a leaner needle.

Offline Fontain25

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Re: V65 PHBH30 jetting
« Reply #5 on: June 14, 2019, 02:10:57 PM »
http://amalcarb.co.uk/downloadfiles/amal/amal_tuning_guide.pdf I realize this isn't your carb but it is a very good guide on getting started with rejetting. Also make certain that all vent hoses have been blown-out with compressed air. Notice in guide that first step is to get proper size main jet.

Offline mauricedonini

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Re: V65 PHBH30 jetting
« Reply #6 on: November 24, 2020, 10:02:20 AM »
I did that mod and the 650 runs way better than the old 500 did with stock carbs.  And gets about 50 mpg.  I've been very happy with it.

This is what I have:

Atomizers (needle jets) drilled by #36 bit
needles = x-8, clip in top notch
main jets = 105
idle jets = 40, roughly 2 turns out on idle screws
choke jets = 60
slides = 40
floats = 11 gram #90101, 25mm float level.
needles and main jets are new.

Stock airbox - sea level, but rides up to 4,000' or so.

Perhaps your choke cables are hanging up?  If the end of the cable casing comes out of its recess it can hold the choke on.

Let us know what you find!

Hi,

Sorry for resurrecting an old post.  Where does one buy the items listed above?

Thank you

Offline guzzisteve

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Re: V65 PHBH30 jetting
« Reply #7 on: November 24, 2020, 10:40:51 AM »
If you are just doing one bike try MG Cycle and if they don't have it call Hermy's in Port Clinton, PA, he's a DelOrto importer and goes by DelOrto part numbers.

https://www.mgcycle.com/

https://herdan.com/
 
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Online Antietam Classic Cycle

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Re: V65 PHBH30 jetting
« Reply #8 on: November 24, 2020, 12:24:33 PM »
If you are just doing one bike try MG Cycle and if they don't have it call Hermy's in Port Clinton, PA, he's a DelOrto importer and goes by DelOrto part numbers.

https://www.mgcycle.com/

https://herdan.com/

Or if neither of those have what you need:
https://www.dellorto.co.uk/product-category/dellorto-motorcycle-carburettors-parts/carburettor-parts/phbh-parts/
Charlie

Offline reidy

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Re: V65 PHBH30 jetting
« Reply #9 on: November 25, 2020, 03:29:33 AM »
I am not sure if this will work. It is a PDF manual

Steve




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