Delortto PHBH30 set up.
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Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Mon Feb 17, 2020 3:55 am quote
I Have read in numerous threads on jet sizing for a Malossi 210 with PHBH 30 carb but each set up is different and none seem close to mine that I can find so I have decided to try do this myself BUT need some help in determining some detail on PHBH jet and needle sizing

1. Main jets I assume are the same across the board so the bigger the number also means the bigger the orifice and therefore richer

2. same would apply for choke and pilot jet

3. Atomizer / needle jet I know that there are different options in terms of size as well as length of the end tips AV has a shorter tip to the AS and from the best of what I have found (Very limited details) the AS would be a leaner jet due to the tips length causing a lower vacuum on the fuel? Is this correct

4. the needle its self they vary on the lengths and diameters across the range but will assume that a good start for a Vespa and Malossi kit is a X2

Please check this and advise
Ossessionato
2 matching N.Z. '69 VBC Super, 177cc Racer, VespaCross Bodge, Puch SRA150, Piaggio Zip 100! & others
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Location: That bushfire place
Mon Feb 17, 2020 10:20 pm quote
"SEARCH " for the answer
Pretty sire a halp-cupcake decent attempt at using the search function will provide the answer
Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Mon Feb 17, 2020 10:48 pm quote
I have searched both google and here and was not able to get the actual answers i am loolking for.

Like why do the PHBH30 use the AS atomizer and what does the extra length on the tip actually do to make it a slightly leaner atomizer than the AV which should be used in a PHBH28.

I have been reading through Dellorto Manuals and I have been getting information from there BUT some more information would be great

most people use an AV atomizer on their PHBH30 from all the posts I have found thus far and I have also noticed that most PHBH30 seem to be shipped with an AV262 which as per both dellorto and sip webist is not correct for the carb
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
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Location: London UK
Tue Feb 18, 2020 12:23 am quote
AS are made for 2 strokes. More economy with no loss in power, as far as I know.
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PX 150
Joined: 15 Sep 2006
Posts: 504
Location: Gold Coast, Australia
Wed Feb 19, 2020 4:40 pm quote
Hey mate you havenít told us what your running other than Malossi210.
Is that an old 210,
210 sport
210 MHR.
Have you match ported the cylinder, what gaskets top bottom how many?
Whatís your squish?
Type of exhaust for example and reed or rotary. Then we can get you closer.
Itís the little details that matter
Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Wed Feb 19, 2020 10:16 pm quote
jimscoot wrote:
Hey mate you havenít told us what your running other than Malossi210.
Is that an old 210,
210 sport
210 MHR.
Have you match ported the cylinder, what gaskets top bottom how many?
Whatís your squish?
Type of exhaust for example and reed or rotary. Then we can get you closer.
Itís the little details that matter
Good Morning Jimscoot

Its a P200e case port matched
210 (to what I can confirm OLD type)
Malossi standard head
standard crank but cut away by machine shop as per Scooterhelp
18' BTDC timing
altitude 1600-1900m
current jets
Main 120
Atomizer AV262 (I have ordered a an AS260, AS262 & AS264, I have also got on hand (AV262 in the bike and a AV264)
idle 55
slide 50
Squish this I have not checked as yet and I also dont think the mechanic that set me up did port timing either so basically a plug and play

That all mentioned I wasn't asking for assistance on the set up its self as yet was more to fully understand the working of the PHBH30 carb and the characteristics of each element... the reason for this is then I can try rectify by marking throttle positions and how the bike runs and also through plug chops and piston wash

Jets I understand, they are marked as 100 jet = 1.00mm 130 jet = 1.30mm so easy the bigger the jet the more fuel the richer the mixture.

I have been told the AS is weaker than an AV of the same size... with regards to this does the longer tip create a higher friction on the mixture and therefore slow it down in turn making it leaner.

As for the needles I understand that each needle will give a different property at a different throttle position, and that the PHBH is supplied fuel mix by the needle across the throttle position... but where does each needle supply more fuel for eg: does a x2 supply richer at between idle and 1/4 throttle and leaner at 1/2 to WOT or vice versa.

I know I have seen a breakdown of needle rich and lean properties but for a keihin so if someone can supply the same for the PHBH X range needles

maybe you can assist with my set up
Addicted
PX 150
Joined: 15 Sep 2006
Posts: 504
Location: Gold Coast, Australia
Thu Feb 20, 2020 2:28 pm quote
Mm you still havenít mentioned the exhaust and that has the biggest influence.
Main jet spot on.
You would start with an AV266 atomiser and X2 needle.
Make sure your needle float Valve is at least a 225, preferably a 250.
Your 55 idle is good. But your slide is to lean go the next richer 45.

MB scooters has an excellent tutorial on phbh carbs and all the different circuits needles etc

https://www.mbscooters.co.uk/info/setting-up-
I can see this link isnít working so just google mbscooters carb setups
Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Thu Feb 20, 2020 10:04 pm quote
jimscoot wrote:
Mm you still havenít mentioned the exhaust and that has the biggest influence.
Main jet spot on.
You would start with an AV266 atomiser and X2 needle.
Make sure your needle float Valve is at least a 225, preferably a 250.
Your 55 idle is good. But your slide is to lean go the next richer 45.

MB scooters has an excellent tutorial on phbh carbs and all the different circuits needles etc

https://www.mbscooters.co.uk/info/setting-up-
I can see this link isnít working so just google mbscooters carb setups
Thank you for the reply, I will check MB scooter.

I am using a Malossi pipe the the needle float was a 200 BUT I have ordered a 300 which I should get today. not sure if in a previous thread I mentioned my altitude at about 1800m (5100ft) so will have to down jet from any low lying jet set ups so will also take that into account

as for the bigger atomizer I am at current WAY TOO rich already and 4 stroking anything over 1/2 throttle, I dont think I can go down more than a 120 main so will try an AS atomizer to see the effect on the mixture to begin with
Addicted
PX 150
Joined: 15 Sep 2006
Posts: 504
Location: Gold Coast, Australia
Fri Feb 21, 2020 8:37 pm quote
Mmm, your jetting seems good
Pull that plug and make sure itís a long reach. So for example b8es not a b8hs.
If that checks out ok make sure the wires in the junction box are all connected properly.
Make sure the stator is ok replace with a known good one if unsure.
Dodgy stator can give symptoms like 4stroking in the higher revs.
Donít keep down jetting until youíre sure that the electrics are good.
Good luck
Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Sun Feb 23, 2020 10:43 pm quote
New information
On Friday I received my atomizers from SIP

installed Saturday morning and went for a spin the BIKE pulled like a freight train, happy as hell upjet back to 130 main and assume it might be little boggy with the way it pulled BUT rather find out too rich than too lean.

Wake up Sunday going to meet friends for a scoot through JHB get on gear and ride AAAAARRRRRGGGHHH too rich and bogging

Not an issue I have the jets in the bike can try the next size down a 125 keep riding and the same issue...

down jet back to the 120 main jet I had when it pulled like stink HUH still bogging

About 3km later while I am pondering what I did differently it occurred to me when I tested I have the engine cowl off so pull over remove the cover and HOLY smokes I have to hold on decided again to upjet to to a 125 and left the cowl at a mates house

112km/h with ease and it still has plenty more BUT I was nervous.

I am running a Malossi E13 air filter I assume that the the hot air under the cowl is not free flowing enough so will try a standard P series bellow from body to carb if that doesn't work I will have to try find a scrap side cowl and cut in some slots on the leading edge to force in fresh air.
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PX 150
Joined: 15 Sep 2006
Posts: 504
Location: Gold Coast, Australia
Mon Feb 24, 2020 1:12 am quote
I forgot to ask about the bellows.
When I bought my phbh30 it was a Malossi kit including reed Valve + holder, x360 manifold, cables throttle and choke and the bellows which fitted perfectly to the frame. I did try a pod but it just wouldnít run right, the bellows improved jetting and dialing in dramatically in the early stages.
This reed kit also sits very low so no problems with fuel starvation. However the rotary valve version sits up higher and at an angle thatís introduces problems with fuel flow when the tank is below half tank

F0D3C94B-E0D1-41B9-9656-421B1B6928FE.jpeg

Hooked
Enough for the wife to tell me to slow down
Joined: 28 Jan 2008
Posts: 329
Location: Johannesburg
Tue Feb 25, 2020 2:12 am quote
Update
So yesterday afternoon I got my hands on a standard P series Bellow which i tried on the bike it is not able to run with the side cover on BUT there is a huge difference in the feeling it has 100% lost power. With filter and side panel or I was able to run the 125main jet, now it is a little flat even with a small 120

but at least it is running, I was also told to try a 50mm dust extraction hose like the one used on the MRP dumbo I got one this morning with out actual dyno figures I would say it is similar to the Standard bellow. I do have to seal the hose where it goes through the body as there might be co2 and and hot air also being sucked into the body in the gap.

I will try a 63mm dust hose maybe the bigger bore will assist with larger volume of air. I will also remove the plastic drip tray under my tank so maybe the cooler air from the horn cast and tunnel will assist with upping the power being produced.

I will be honest its still WAY faster than stock BUT after I felt it with out the side cover and the malossi air filter I would much rather prefer that ride.

87983810_2530945083784509_3035453744012591104_n.jpg

87398693_184905669407382_8579808661138833408_n.jpg

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