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 .

[Rangerscott]

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

[Wancsta]

Originally Posted by jeffrey

Look in the Tech Favorites at the top of the dual sport index. PZ30 VS Mikuni carb comparison with pictures.

Thank you exactly what I was looking for!

[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

[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.

[Wancsta]

Originally Posted by Megadan

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.

Nice! Was there enough material there to hog it out a little?

[Megadan]

Originally Posted by Wancsta

Nice! Was there enough material there to hog it out a little?

Maybe a tiny bit, but there is no way to know how thick the inner metal sleeve is on that intake manifold.

[Wancsta]

Originally Posted by Megadan

Maybe a tiny bit, but there is no way to know how thick the inner metal sleeve is on that intake manifold.

Ok thanks probably not worth the hassle.

[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.

[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.