VM26 (clone) vs PZ30 help

[Wancsta]

Has anyone that has done the swap actually measured the inner bore diameter on both carbs? Both are supposed to be 30mm. I'm just wondering if there's even a minute performance gain to be had by removing a perfectly good running PZ30. Tuning and butterfly chokes being the same the only difference could be inner bore diameter. So if anyone is in the middle of doing a swap or has both on hand could you please take a quick measurement?

[Megadan]

Originally Posted by Wancsta

Has anyone that has done the swap actually measured the inner bore diameter on both carbs? Both are supposed to be 30mm. I'm just wondering if there's even a minute performance gain to be had by removing a perfectly good running PZ30. Tuning and butterfly chokes being the same the only difference could be inner bore diameter. So if anyone is in the middle of doing a swap or has both on hand could you please take a quick measurement?

Its not done for performance. Its because mikuni jets are easier to come by.

[Wancsta]

I had tried searching and with all these swaps I was surprised to see no one ever did a side by side shot or at least a quick measurement.

[enforcer89]

Heres my finds my vm26 and jets I ordered came fast the jets I ordered off amazon fit both my stock carb off hawk and the vm26 . I put a 115 main jet in both and swapped back and forth the only gain I had was the vm26 idled a bit better off a cold start than stock carb .

[Megadan]

Originally Posted by enforcer89

Heres my finds my vm26 and jets I ordered came fast the jets I ordered off amazon fit both my stock carb off hawk and the vm26 . I put a 115 main jet in both and swapped back and forth the only gain I had was the vm26 idled a bit better off a cold start than stock carb .

The problem isn't the main jets with the PZ30, it's the pilot jet/slow jet that is the problem. Also, the needle has no adjustability to it, so washers have to be stacked.

Just to sate your curiosity, I measured both carbs with my calipers. Stock PZ30 at manifold - 29.92mm. Mikuni VM26 "30mm" 29.87, with a small margin of error granted because there is no clean edge for my calipers to grasp. So, in short, they are both 30mm. I will note that the stock carb throat is actually not centered in the body on mine, and it sits lower than the inlet manifold port a little, the VM26 I ordered centers up perfectly.

[Wancsta]

Originally Posted by Megadan

The problem isn't the main jets with the PZ30, it's the pilot jet/slow jet that is the problem. Also, the needle has no adjustability to it, so washers have to be stacked.

Just to sate your curiosity, I measured both carbs with my calipers. Stock PZ30 at manifold - 29.92mm. Mikuni VM26 "30mm" 29.87, with a small margin of error granted because there is no clean edge for my calipers to grasp. So, in short, they are both 30mm. I will note that the stock carb throat is actually not centered in the body on mine, and it sits lower than the inlet manifold port a little, the VM26 I ordered centers up perfectly.

Thank you for the confirmation. I am completely happy with my pz30 at least for now. I have an eBay exhaust waiting to go on once I get a minute. Even so I am no stranger to drilling jets and have a micro hand drill set exactly for that already.

I did notice in the tech info thread about the carb throat and wasn't sure if maybe that was specifically matched to our manifolds? Or is it just the design? If that were the case I would suspect the mikuni would actually be a slight downgrade (performance wise) if it was not smoothed out in that area.

[Megadan]

Originally Posted by Wancsta

I did notice in the tech info thread about the carb throat and wasn't sure if maybe that was specifically matched to our manifolds? Or is it just the design? If that were the case I would suspect the mikuni would actually be a slight downgrade (performance wise) if it was not smoothed out in that area.

I checked both. I had the intake manifold off too, and decided to see the alignment because of this very same thought. Mikuni lined up perfectly, PZ30 did not.

[Shaliza]

Originally Posted by enforcer89

Heres my finds my vm26 and jets I ordered came fast the jets I ordered off amazon fit both my stock carb off hawk and the vm26 . I put a 115 main jet in both and swapped back and forth the only gain I had was the vm26 idled a bit better off a cold start than stock carb .

I bought a VM26 mikuni clone and jets for it off of Amazon for my Magician 250, and for some reason, the mikuni jets would not fit the VM26 carb but they would fit the stock Sheng Wey PZ30 carb. See pic below: the jet on the right came in the VM26 carb. The one on the left is the 110 jet that would not fit in the mikuni carb.

Did anyone have this problem or did I receive a wrong product?

Edit: By "not fit" I mean, it would get tight after a few turns and not fully seat.

[Rangerscott]

For the knock off keihen carbs, just have to search ebay "gy6 jets."

[Ariel Red Hunter]

Originally Posted by Wancsta

Has anyone that has done the swap actually measured the inner bore diameter on both carbs? Both are supposed to be 30mm. I'm just wondering if there's even a minute performance gain to be had by removing a perfectly good running PZ30. Tuning and butterfly chokes being the same the only difference could be inner bore diameter. So if anyone is in the middle of doing a swap or has both on hand could you please take a quick measurement?

If you have a perfectly good running PZ30, you are very lucky and there is no point in changing to a Mikuni. If you go to an after market exhaust system and/or open up the air box, you might want to change...ARH

[hertz9753]

I bought the same set of jets and had the same problem. I wrote something about not buying the buying the Wings jets if you will be using the Mikuni clone.

[Shaliza]

Originally Posted by hertz9753

I bought the same set of jets and had the same problem. I wrote something about not buying the buying the Wings jets if you will be using the Mikuni clone.

So which jets do you recommend if I want to upgrade the jet in my Mikuni clone?

Also I wonder why many people (Megadan and many other people who reviewed on the Wings jet on amazon) were able to install it in their Mikuni clone

[Megadan]

The funny thing is, just out of curiosity, I went and tried to screw one of the jets I got from Wingsmoto into my stock PZ30 and it gets tight after a couple of turns. Yet on my VM26 clone, they screw right in with no trouble. My 110 main is a Wingsmoto main jet.

I then dug into my Bag-O-Jets and fished out the 100 main that came in the VM26 and compared it to the rest of my Wings jets... same threads. My PZ30's 98 main jet on the other hand is every so slightly different.

So I can only assume that Wingsmoto is packaging and selling both types of jet as the same thing, or there was a mix up somewhere along the distribution chain. It wouldn't be surprising.

[hertz9753]

Originally Posted by Shaliza

So which jets do you recommend if I want to upgrade the jet in my Mikuni clone?

Also I wonder why many people (Megadan and many other people who reviewed on the Wings jet on amazon) were able to install it in their Mikuni clone

I ordered Mikuni VM28 pilot and main jets. I will give the numbers later after a long shift of sleeping.

[humanbeing]

The pic showed it won't works from day 1. It don't matches ANY pics from Jetsrus/ others that sold cheap copies
[Typical chinese]
PZ30 (aka Keihin clone)

Mikuni