Author Topic: RGS Dellorto PHF32 jetting  (Read 1142 times)

Offline Piranha Brother 2

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Re: RGS Dellorto PHF32 jetting
« Reply #15 on: September 12, 2018, 00:04 »
I thought anything from 1 1/4 to 1 3/4 turns out was within range? Could be wrong ...

My experience has been to find sweetest idle and if fluffy picking off off the stops then richen slightly by about 1/8 turn.
What ... leave it standard??!!

Offline Paul Marx

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Re: RGS Dellorto PHF32 jetting
« Reply #16 on: September 12, 2018, 07:56 »
I thought anything from 1 1/4 to 1 3/4 turns out was within range? Could be wrong ...

My experience has been to find sweetest idle and if fluffy picking off off the stops then richen slightly by about 1/8 turn.

Me too.

Paul

Offline murphus

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Re: RGS Dellorto PHF32 jetting
« Reply #17 on: September 14, 2018, 15:05 »
I think I'm getting close. Pulled the slow speed/idle jets, right jet was plugged, center not but who knows what might have fallen out during removal. Flushed the circuit and swapped the no. 58 slow speed jets for no. 55. Back together and appears to be running well. Idle is stable and the engine much crisper when pulling the throttle off idle. Ended up with the fuel/air screws at about 1-3/4 turns out. So, with luck it's set to go. Only question still on my mind is, fuel/air mixture adjustments seem very nuanced. As in, the engine response to changes in the mixture seems slow. Turn a mixture screw in say 1/2 turn and it's a few moments before a real change is heard/felt. Same on all three carbs. Is that normal? Indicative of anything else like improper float levels? Which I did confirm at approximately 18mm.

Offline Laverda SF

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Re: RGS Dellorto PHF32 jetting
« Reply #18 on: September 15, 2018, 02:54 »
What exhaust pipes, mufflers and cam are you running and give us a hint about your ignition system ?

Appears you guys got it straightened out ;o)

Just curious did you have to leave PHF 32's open mount or did they work with filters?

I played with VHB 32's onna SFO  for like 45 years ;o)
« Last Edit: September 16, 2018, 05:07 by Laverda SF »

Offline Brett

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Re: RGS Dellorto PHF32 jetting
« Reply #19 on: September 15, 2018, 10:49 »
I think I'm getting close. Pulled the slow speed/idle jets, right jet was plugged, center not but who knows what might have fallen out during removal. Flushed the circuit and swapped the no. 58 slow speed jets for no. 55. Back together and appears to be running well. Idle is stable and the engine much crisper when pulling the throttle off idle. Ended up with the fuel/air screws at about 1-3/4 turns out. So, with luck it's set to go. Only question still on my mind is, fuel/air mixture adjustments seem very nuanced. As in, the engine response to changes in the mixture seems slow. Turn a mixture screw in say 1/2 turn and it's a few moments before a real change is heard/felt. Same on all three carbs. Is that normal? Indicative of anything else like improper float levels? Which I did confirm at approximately 18mm.
 

Take it for a ride and get it to operating temp then redo the mixtures... if you have been playing about without a good run you can get false readings.. . Also what you need to remember is that the balance hose will tend to mask the mixture screws a bit as there is a little bleed from the other carbs. esp if you not experienced/used to these bikes.

Proper way to set it is to remove the balance hose, sync the carbs... set the individual carbs.. then refit balance hose and fine fettle.

Sitting on the fence 120 or 180 that is the question ?

Offline murphus

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Re: RGS Dellorto PHF32 jetting
« Reply #20 on: September 16, 2018, 04:27 »
Did a 50 mile run today. Running really nicely, idles well, and pickup is crisp and strong. Only thing I'm noticing now is a tendency to hunt at low throttle openings. At maybe 1/8th throttle, low rpm, steady speed it stutters just a bit. The moment you crack the throttle, even just a little, it's clean and crips, pulling strongly. It's far better than it was before rebuilding the carbs and replacing all the jets. Only thing I didn't replace was the slides. Now running 55 slow speed jets, otherwise everything to stock and new. I feel like it's 95 percent there, would love to get that last bit, but absolutely running far better than ever before. And to answer a previous question, DMC ignition, stock cams, aftermarket mufflers with, near as I can tell, no packing at all, and stock airbox and filter but previous owner cut holes in the bottom of the airbox. And running the snorkle.
Richard

Offline Laverda SF

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Re: RGS Dellorto PHF32 jetting
« Reply #21 on: September 16, 2018, 05:15 »
One thing about Dellortto's is that you gotta keep them clean - Rust Check Red works great with a lot of polishing.

Your taking a chance if you skip a year or two.

As far as ignitions, pipes Vs tire sizes and jetting it'a all up to you.
« Last Edit: September 16, 2018, 05:22 by Laverda SF »