- Location
- Sicily, IT
Hey guys just picked up a pair of 48mm annular discharge carbs and not sure who made them. Im thinking blackjack??
What kind of carbs are these?
- Thread starter cam_lg
- Start date
- Location
- Sicily, IT
Just took them apart for cleaning, theyve got 12 discharge holes and the jetting is below.
2.3 N/S silver spring
150 low
56 high
.....
Am i just a noob or is this jetting crazy lol
2.3 N/S silver spring
150 low
56 high
.....
Am i just a noob or is this jetting crazy lol
Last edited:
- Location
- Sicily, IT
How hard would would they be to tune for freestyle?
cookn
Kamikaze
- Location
- where you live
man those are crusty, they dont look like black jacks to me but who knows. My personal opinion is that you would spend more fully rebuilding them then they are worth but again just an opinion. Most annular discharge carbs were better for wide open throttle applications because of the reduced carb signal from having no bomb sight but people have got them to work for them, it all depends on your setup. I have also seen people bang their heads against a wall trying to get weird old carbs tuned in with no support from the manufacturer
Quinc
Buy a Superjet
- Location
- California
I would fully strip those and soak them in chem dip for an hour or so to get all the crust out. Also spray some carb cleaner or pressure some gas and squirt it into the fuel inlet to make sure it flows out of the 12 holes.
- Location
- Sicily, IT
They're soaking in it now, all holes are clear. These bad boys were pumping and running before i got them.
These aren't BlackJacks. They're yet another copy of Jack Green / Green Racing carbs.
Annular discharge carbs are made solely for top end. They lag in the midrange without ridiculous amounts of signal. Depending on your engine they can go lean enough to cause seizures. They worked okay, not great, on race runabouts in the '90s but were a major pain to tune. Tuning these for freestyle will be a nightmare without question. You might need restrictive air filters and a tight intake tract just to gain good enough signal to get somewhat close.
My advice would be to clean them up and sell them for the highest offer you get -- which admittedly might not be much. Buy yourself some stock 46s instead. They'll run better, accelerate harder and be exponentially easier to tune.
(corrected typo)
Annular discharge carbs are made solely for top end. They lag in the midrange without ridiculous amounts of signal. Depending on your engine they can go lean enough to cause seizures. They worked okay, not great, on race runabouts in the '90s but were a major pain to tune. Tuning these for freestyle will be a nightmare without question. You might need restrictive air filters and a tight intake tract just to gain good enough signal to get somewhat close.
My advice would be to clean them up and sell them for the highest offer you get -- which admittedly might not be much. Buy yourself some stock 46s instead. They'll run better, accelerate harder and be exponentially easier to tune.
(corrected typo)
Last edited:
- Location
- Sicily, IT
So some regular ole 46 SBN's from Amazon would be a better choice?
Sadly, yes.
46 SBNs are underrated. Jetted correctly, bone stock 46s can perform 90~95% as well as the best carbs on the market and outperform everything else. For the money they can't be beat. You can also throw two factory square nose air boxes on top to help keep out water.
Get a good manifold and a decent set of reeds to go with them. Heck, Carbontech low-tension or OEM Kawasaki SXR petals on 62T cages work great and last forever. You'll have an inexpensive, reliable, easy-to-maintain intake setup that keeps you riding.
46 SBNs are underrated. Jetted correctly, bone stock 46s can perform 90~95% as well as the best carbs on the market and outperform everything else. For the money they can't be beat. You can also throw two factory square nose air boxes on top to help keep out water.
Get a good manifold and a decent set of reeds to go with them. Heck, Carbontech low-tension or OEM Kawasaki SXR petals on 62T cages work great and last forever. You'll have an inexpensive, reliable, easy-to-maintain intake setup that keeps you riding.
- Location
- Sicily, IT