Adjusting brozz carb

[Taylor250]

Hi all,
Just installed a new exhaust and deleted the restrictive snorkel on the air box on my 18’ brozz 250....I live in nj, should I adjust my carb and/or change the jetting with those changes? After warming the bike up and going for a ride I notice on heavy throttle is bogs down a bit then catches up. Guessing I need to adjust my fuel and rejet. Any advise will do, Thanks


Update: Added a small washer under the needle and she runs much better now. Still has some low end power loss but I think rejetting it correctly will fix that.

[PeaceSportsAtlanta]

MotoCheez has a great carb tutorial.



If under 1000 ft, probably best to go up a size. He used a 115. I had Tennessee customer (unsure elevation) say 115 was about right as well.

[Megadan]

The exhaust will almost always require at least jetting up on the main. A 110, 112, or 115 main with intake and exhaust is usually the ticket on most of these bikes, depending on elevation. I would say start with a 115, because it's always better to be a bit rich than a bit lean.

[Taylor250]

Originally Posted by Megadan

The exhaust will almost always require at least jetting up on the main. A 110, 112, or 115 main with intake and exhaust is usually the ticket on most of these bikes, depending on elevation. I would say start with a 115, because it's always better to be a bit rich than a bit lean.

Awesome thanks for the reply. I watched the motocheez vid but he doesn’t say where he got his jets from. Are there a certain kind I need to get for these bikes? The motocheez website has the pilot jets that you can buy on amazon but not the main jets. Any idea what ones I need? Thanks

P.s. I added the washer on needle and the bike runs great other then some power loss down low. I think proper jetting will fix that tho.

[Taylor250]

Originally Posted by PeaceSportsAtlanta

MotoCheez has a great carb tutorial.



If under 1000 ft, probably best to go up a size. He used a 115. I had Tennessee customer (unsure elevation) say 115 was about right as well.

Thanks!

[mattygritt]

Also curious about this. What types of exhaust systems are usually used on this bike? Is the stock fine with some jetting at the carb? And like Taylor asked, where do people usually pick up their jets from?

[Megadan]

Originally Posted by Taylor250

Awesome thanks for the reply. I watched the motocheez vid but he doesn’t say where he got his jets from. Are there a certain kind I need to get for these bikes? The motocheez website has the pilot jets that you can buy on amazon but not the main jets. Any idea what ones I need? Thanks

P.s. I added the washer on needle and the bike runs great other then some power loss down low. I think proper jetting will fix that tho.

Almost all of these bikes come from the factory with a PZ30 clone, and thus use a Keihin 99101-393 style main jets.

I personally recommend OEM jets if at all possible, but you can get these bikes running decent enough on the cheap jet kits that cost almost the same as one OEM jet. https://www.amazon.com/10pcs-Carbure...%2C226&sr=8-26


If you find that you can't get the bike to ever run right with the cheap jets, that is when the OEM or OEM Equivalent aftermarket jets will become more necessary. The biggest issue with the cheap jets is that they are not always sized correctly, or consistently.