Idle screw, hp carb dellorto Sha clone

Otto Neumann

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I understand what you are saying about extra hole, hole positions etc. I'm waiting for other jets to test them. If then is still not idling, I leave the nt type.
EDIT: What would you recommend, a Mikuni VM18 or a Dellorto PHBG 19mm?
Hey there mate, the PHBG 19 AS would be perfect; mind that the PHB type carburetors can be nasty ones to tune, but it will def yield you more power than the SHA or the NT. Refrain from buying those chinese imitations, Dell'orto's name alone is a warranty:

I can get you a genuine one straight from the factory, here in Seregno, Italy.
 

ycodryn

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Hey You are from Italy? Soon I will test the Sha first with lower jets, they sent me wrong size 4mm and now I'm waiting for 5mm jets (from 65 to 85, 10 pieces). If after my tweaks to the carb and the jets I still can't use it and is a waste, I will speak with you for a genuine piece.
Here is the bike:
 

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Otto Neumann

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Hey You are from Italy? Soon I will test the Sha first with lower jets, they sent me wrong size 4mm and now I'm waiting for 5mm jets (from 65 to 85, 10 pieces). If after my tweaks to the carb and the jets I still can't use it and is a waste, I will speak with you for a genuine piece.
Here is the bike:
Oh yeah, I am! Probably the only, Dell'Orto carbs are numero uno

Def ditch the SHA, it's used on Piaggio Ciaos and similar scooters, everybody that elaborates those machines always tells to take the SHA and swap it for a PHBG; a 19mm may be too big, I'd stick with a PHBG 15 or even better a 17.5; so that you still have some decent power at lower rpms.

Mind one thing: The SHA has one jet that must cover the whole throttle range, so in a certain sense, you'll have to settle for a compromise: You won't be able to find a perfect tuning with it.

I'm currently slapping an SHA 15.15 on a 49cc 4 stroke huasheng and I'm working on a 3D printable collector for it.
Notice the difference in quality in the original Dell'orto.

1656972750288.png
1656972849228.png
 

DAMIEN1307

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Hey You are from Italy?
Oh yeah, I am! Probably the only
We actually have 4 members in Italia,

One in Milano, One in Bologna, one in Roma, and one in Ceglia Messapica.

From Milano to Ceglia Messapica, you four cover the entire length of Italia from northern to southern Italia, from the Swiss border to the Mediterranean Sea...lol.
 

ycodryn

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If I only knew about this things when I was in Italy in holy days... Torino, Milano, Sardegna. Anyway since I changed the muffler with the one from the picture, now I have more power. If with the default muffler on a hill I would be using all the throttle, now I'm using only 20%-30%, that with the stock carb, also I took out the idle jet for about 2 turns. With the muffler change I also disassembled the engine head, cleaned the piston, grinded the in/out holes and sandpaper the head. Now is a joy to ride it and hear it. I'm waiting the jets to test the sha. On Sha I borred a little the air holes, made another hole between 2 from the emulsion tube, tuned the slide for air leak and grinded the angle. I will test it first with a 68 jet to see how is running. The lowest one will be 65 but maybe is to lean. If won`t stay to idle I will pm you :))
Edit: forgot to say that original dellorto is just sexy.
Edit 2: I'm more interested in low rpm power then speed. With that fatbike that is already heavy, me having 90kg I'm for torque 😂
 

Otto Neumann

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If I only knew about this things when I was in Italy in holy days... Torino, Milano, Sardegna. Anyway since I changed the muffler with the one from the picture, now I have more power. If with the default muffler on a hill I would be using all the throttle, now I'm using only 20%-30%, that with the stock carb, also I took out the idle jet for about 2 turns. With the muffler change I also disassembled the engine head, cleaned the piston, grinded the in/out holes and sandpaper the head. Now is a joy to ride it and hear it. I'm waiting the jets to test the sha. On Sha I borred a little the air holes, made another hole between 2 from the emulsion tube, tuned the slide for air leak and grinded the angle. I will test it first with a 68 jet to see how is running. The lowest one will be 65 but maybe is to lean. If won`t stay to idle I will pm you :))
Edit: forgot to say that original dellorto is just sexy.
Edit 2: I'm more interested in low rpm power then speed. With that fatbike that is already heavy, me having 90kg I'm for torque 😂
Mind one thing: Stick with the OG untampered airbox, because SHA carburetors doesn't require a lot of air like a PHGB, tampering with the stock airbox or adding an high flow filter may throw off your tuning, which per se on the SHA it's already a punch in the eye!

You could grind a little around the venturi intake behind the filter, to form a sort of velocity stack, but mind which it will compromise the semiautomatic choke's functionality.

Since it's a 2 stroke, PHBGs comes with an optional built in mixer circuit, you could fit cylidrical oil tank just under your seat and forget about mixing oil and gas, but that will bring a new thing in the quotidianity of your maintenance:

The carburetor should be taken off the bike and washed every 5 full tanks, to avert the clogging of the mixer circuit and engine seizure :)
 

Otto Neumann

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We actually have 4 members in Italia,

One in Milano, One in Bologna, one in Roma, and one in Ceglia Messapica.

From Milano to Ceglia Messapica, you four cover the entire length of Italia from northern to southern Italia, from the Swiss border to the Mediterranean Sea...lol.
Oh boy, are they actually active in here? o_O

Motorized bicycles are illegal in Italy, because without an insurance and homologation they aren't allowed to hit the streets; I'm surprised to see a few more idgafers like me around, gotta meet them!
 

ycodryn

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The Sha clone came with the air filter frome the picture from above but I adapted it to the stock carb. Comparing the jet that came with the clone with the wrong jets that the aliexpress sent (4mm) I think it was something to .90 and I think that was the problem with not staying at idle. Maybe another week until the 5mm jets are coming (If they sent the wrong size again I will burn the carb 😂). If I knew that the "performance" carb is a dellorto clone, I would go for a original one but I gained new information and found new things about carbs with this mistake.
 

DMoore0079

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The Sha clone came with the air filter frome the picture from above but I adapted it to the stock carb. Comparing the jet that came with the clone with the wrong jets that the aliexpress sent (4mm) I think it was something to .90 and I think that was the problem with not staying at idle. Maybe another week until the 5mm jets are coming (If they sent the wrong size again I will burn the carb 😂). If I knew that the "performance" carb is a dellorto clone, I would go for a original one but I gained new information and found new things about carbs with this mistake.

I battled that SHA clone for awhile before ultimately giving up. The biggest gripe I had was that there was no mixture adjustment aside from modifying the slide or the emulsion tube. They run very rich by nature, and almost always require a smaller main jet than you'd run in an NT.

Last time I was on Treatland, I saw that they had an Arbeo SHA clone (better quality than the Chinese Runtong) that actually had a mixture screw. Maybe something like that would work better?
 

Otto Neumann

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I battled that SHA clone for awhile before ultimately giving up. The biggest gripe I had was that there was no mixture adjustment aside from modifying the slide or the emulsion tube. They run very rich by nature, and almost always require a smaller main jet than you'd run in an NT.

Last time I was on Treatland, I saw that they had an Arbeo SHA clone (better quality than the Chinese Runtong) that actually had a mixture screw. Maybe something like that would work better?
Get an original Dell'Orto instead of these chinese clones: The dudes sitting behind the desk inside their factory, in China, instead of putting years of expertise into their work, they not only just copied the work of an illustrious company; they also applied all sort of curtailments ranging from the machining quality all the way to the materials itself, to shave every single penny from the production costs. The result is a cheap carburetor that not
only works as poorly as it has been reverse engineered and manufactured, but in order to match the quality of a genuine one, you need ten of them.

If you really want to have a decent carburetor, get a PHBG. SHAs are really useful only on contraptions like minibikes, miniquads or bikes that are built substantially to just *run* without putting out some serious juicy power on the real wheel!
 
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