What carb do I get ? Urgent help needed !

sonic883

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Joined
Apr 28, 2021
Messages
85
Guys, I have a 2 stroke 80cc engine. I have performance parts such as a mz65 clone pipe (expansion chamber), high compression head, and a “high performance” carb, runtong. You would think with all that performance parts it would go faster than a stock engine. But it’s really not that much more powerful than stock. I am almost convinced I need to tune my carb, or should I go back to nt. I really don’t know I just want to go much faster, it feels kinda restricted, could it be that I need to jet the carb ? I might go back to a speed nt carb, because it just felt better back then? I need help to get this bike to run better.
 

DAMIEN1307

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Jul 23, 2020
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For what my two cents is worth, I run a stock CG set up.

A Hyper Bike Company Beach Cruiser frame, a Zeda 80 motor, 3 spoke design mag wheels, a K&N wannabe airfilter, and just changed my carby to a JRL Bofeng carburetor which is nothing more than a "beefed up" NT type carb but better built, and using a 36 tooth sprocket.

I'm using the stock exhaust and head as well...I don't believe in using fancy exhaust or heads that deliver very little value for the money spent unless you are prepared to do more extensive modifications such as reed valve carbies, windowed pistons, porting, improved "squish". etc, just to get the bolt on so-called "improved" this or that add-on things to even work properly.

I achieved just a little bit more than 50 MPH on a flat paved road and went uphill doing 37 MPH using a 32:1 fuel/oil mix with full synthetic oil and ethanol-free petrol 87 octane.

Pics of finished product below...DAMIEN

IMG_0353.jpg
IMG_0348.jpg
IMG_0352.jpg
 

sonic883

Member
Joined
Apr 28, 2021
Messages
85
For what my two cents is worth, I run a stock CG set up.

A Hyper Bike Company Beach Cruiser frame, a Zeda 80 motor, 3 spoke design mag wheels, a K&N wannabe airfilter, and just changed my carby to a JRL Bofeng carburetor which is nothing more than a "beefed up" NT type carb but better built, and using a 36 tooth sprocket.

I'm using the stock exhaust and head as well...I don't believe in using fancy exhaust or heads that deliver very little value for the money spent unless you are prepared to do more extensive modifications such as reed valve carbies, windowed pistons, porting, improved "squish". etc, just to get the bolt on so-called "improved" this or that add-on things to even work properly.

I achieved just a little bit more than 50 MPH on a flat paved road and went uphill doing 37 MPH using a 32:1 fuel/oil mix with full synthetic oil and ethanol-free petrol 87 octane.

Pics of finished product below...DAMIEN

View attachment 161542View attachment 161543View attachment 161544
Lucky you, hit around 30mph on flat, and that’s on a good day
 

DAMIEN1307

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Staff member
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Jul 23, 2020
Messages
3,036
Lucky you, hit around 30mph on flat, and that’s on a good day
It's NOT luck...It was my way of trying to encourage you to put things back to stock and then we all might be able to help you tweak things in "Ship-shape and Bristol fashion"...DAMIEN
 

Cannonball3

Active Member
Joined
Sep 11, 2021
Messages
231
As I have said in several past threads the Bofeng is king of the stockish carbs. I bought 5 of them a while back, and all my bikes run them. All improved greatly over the NT, with minor adjusting of the needle. Even the YD. The needle profile and jetting is excellent. Look at the internals of the slide area, its polished! Our temps have dropped from the mid 70s to mid 40s. The carb still runs well once the needle was raised to the next notch to richen the low end. I was expecting a need to change to a richer jet, so far no. These run extremely well with a G4 cylinder. I no longer run the common old style cylinder. Dont waste your money on the 15/15 Delorto clones. Even the one with the adjustable idle circuit sucks
compared to the Bofeng.
 

DieselTech

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Sep 18, 2021
Messages
2,223
If you want a good carb, you have to spend some good cash. The bofeng is best overall in the nt style carbs. I would go chainsaw carb, or buy a genuine dellorto carburetor.
 

Karl Snarl

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Joined
Sep 20, 2019
Messages
3,397
Guys, I have a 2 stroke 80cc engine. I have performance parts such as a mz65 clone pipe (expansion chamber), high compression head, and a “high performance” carb, runtong. You would think with all that performance parts it would go faster than a stock engine. But it’s really not that much more powerful than stock. I am almost convinced I need to tune my carb, or should I go back to nt. I really don’t know I just want to go much faster, it feels kinda restricted, could it be that I need to jet the carb ? I might go back to a speed nt carb, because it just felt better back then? I need help to get this bike to run better.
Get a Bofeng NT carb. They are nice, work great, and built to impress. Someone here showed me them the other week, so I tried it. I'm very impressed with them. If you want to do some work, and get a lot more power, a rwj-4b or hs-254b tilson saw carb will work magic.
 
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