Mike Cyanide
Well-Known Member
Super simple carb hence a super simple tuning guide.
Intsall/start procedure.
1.When installing mount carb as level as possible.
2. Place a 3/ or 19mm o ring between Intake and carb body.
3. Place clip on middle position of needle.
4. When threading slide/cable cap make sure it's threading easily and flush secure by hand and then with slight pressure torque cap with channel locks.
5 turn i dle screw til snug and back off about 2 1/2 turns.check slide for smooth crisp operation along with choke operation.
6. Install air cleaner(if red) cut lower portion of skull off(everything bellow "eyes" screws. Aside from outer ring that goes around choke plate(if black"punisher or skull").
6. Nt/speed set choke to about 3/4 on position. To start. Bofeng choke can be fully engaged.
Tuning
Ride bike (if running smoothly enough) until at operating temperature.
note 3/4 throttle and below is controlled by
needle setting. Above 3/4 is main jet
Lean symptoms (no load)
1. Erratic idle and or surging idle.
2..bog (delayed) under abrupt amd substantial throttle input.
3. Throttle hangs/hanging revs (engine takes excessive amount of time to return to idle. When rpms are increased
4. Engine may stall cemetery under heavy throttle or at WOT when input is abrupt.
5 pinging/spark knock/overheat/smoldering. (Extreme case)
Symptoms. Of rich condition(no load)
1. Excessive smoke.
2 bogs(slow to rev+almost constant 4 stroking) under heavy and abrupt throttle input.
4. Excessive vibration(4 stroking) under light throttle.
5. Shaking stall out when abrupt WOT
6 oil discharge from exhaust exit
Symptoms of lean condition (under load)
1 erratic idle and possible run away
2. Bog(hesitation/stumble) under hard acceleration at low speeds or uphill
3. Rpms away when clutch engaged
4. Miss or occasional pop at high speed/rp
5. Revs hanging no throttle input high speed=rpm.
6. Excessive heat/smoldering/afterfires, (backfire thru exhaust), SHUT DOWN IMMEDIATELY!
Symptoms of rich condition (under load)
1. 4 STROKING!
2 Lack of power
3. Excessive smoke
4 vibration (4 Stroking)
5. MOSTLY JUST 4 STROKING. makes unrideable
6. Stalls at WOT (very lowspeed).
How to ensure a safe tune
1. Richen needle setting til 4 stroking. Then back off 1 position. Bike should 4 stroke under light load at low throttle input.
2 Jetting. Increase jet size til 4 stroking. Back or 1,2 it 4 st4oking persists at WOT at high rpm.
IMPORTANT NOTES
1. Float height plays a major role in A/F mixture. 21mm is corrected float height (measured bowl off with float resting on tang upside down. Measurement taken from bowl mating surface. Even If height is correct. If your having abnormal tuning issues intermitantly lean or starving for fuel,lean on needle position bur 4 stroking on main jer
,flooding,4 stroking on leanest needle setting . Float height may need to be adjusted to suit your situation. Even if carb is somewhat level. Float height may need to be higher or lower than recommend in.some cases. These problems may also stem from - stuck Float needle,porous Float,clogged fuel inlet, clogged or debris in jet,clogged fuel filter,fuel line collapsed,excessive fuel leak,clogged petcock/sock in tank and vapor lock.o
2. Extreme drop in temperature (-30°-40° from correct tune) WILL LEAN MIX/Extreme rise in temperature WILL RICHEN MIX (+30°-+40° from correct tune)
3. Adding or removing air cleaner will richen or lean mix
4. +Altitude Wil richen m8x
5. Increasing fuel to oil ratio will lean mix. (Example from 40:1 to 20:1= leaner
6. Loose exhaust or leaking gasket will cause leaner conditions however will not affect idle
7 LEAN=HOT RICH=COOL but dirty
8. Excessive vibration can cause fuel to foam in carb causing lean mix
CONCLUSION
For the most part a smooth ride is a safe one for your motor. 4 stroking when cold and under light load/throttle input Is not only acceptable but recommended for a healthy motor. DO NOT RIDE WITH A LEAN OR RICH CONDITION. IT cause excessive wear or immediate damage. In extreme case total failure. If this guide hasn't properly setup your new rig or corrected your issue then get that gumout/carb cleaner and find that air leak or maybe you should consider an e bike... and become the constant butt of. Ya jokes! I'll have plenty of time to tell you all of them while it charges! Lol
Intsall/start procedure.
1.When installing mount carb as level as possible.
2. Place a 3/ or 19mm o ring between Intake and carb body.
3. Place clip on middle position of needle.
4. When threading slide/cable cap make sure it's threading easily and flush secure by hand and then with slight pressure torque cap with channel locks.
5 turn i dle screw til snug and back off about 2 1/2 turns.check slide for smooth crisp operation along with choke operation.
6. Install air cleaner(if red) cut lower portion of skull off(everything bellow "eyes" screws. Aside from outer ring that goes around choke plate(if black"punisher or skull").
6. Nt/speed set choke to about 3/4 on position. To start. Bofeng choke can be fully engaged.
Tuning
Ride bike (if running smoothly enough) until at operating temperature.
note 3/4 throttle and below is controlled by
needle setting. Above 3/4 is main jet
Lean symptoms (no load)
1. Erratic idle and or surging idle.
2..bog (delayed) under abrupt amd substantial throttle input.
3. Throttle hangs/hanging revs (engine takes excessive amount of time to return to idle. When rpms are increased
4. Engine may stall cemetery under heavy throttle or at WOT when input is abrupt.
5 pinging/spark knock/overheat/smoldering. (Extreme case)
Symptoms. Of rich condition(no load)
1. Excessive smoke.
2 bogs(slow to rev+almost constant 4 stroking) under heavy and abrupt throttle input.
4. Excessive vibration(4 stroking) under light throttle.
5. Shaking stall out when abrupt WOT
6 oil discharge from exhaust exit
Symptoms of lean condition (under load)
1 erratic idle and possible run away
2. Bog(hesitation/stumble) under hard acceleration at low speeds or uphill
3. Rpms away when clutch engaged
4. Miss or occasional pop at high speed/rp
5. Revs hanging no throttle input high speed=rpm.
6. Excessive heat/smoldering/afterfires, (backfire thru exhaust), SHUT DOWN IMMEDIATELY!
Symptoms of rich condition (under load)
1. 4 STROKING!
2 Lack of power
3. Excessive smoke
4 vibration (4 Stroking)
5. MOSTLY JUST 4 STROKING. makes unrideable
6. Stalls at WOT (very lowspeed).
How to ensure a safe tune
1. Richen needle setting til 4 stroking. Then back off 1 position. Bike should 4 stroke under light load at low throttle input.
2 Jetting. Increase jet size til 4 stroking. Back or 1,2 it 4 st4oking persists at WOT at high rpm.
IMPORTANT NOTES
1. Float height plays a major role in A/F mixture. 21mm is corrected float height (measured bowl off with float resting on tang upside down. Measurement taken from bowl mating surface. Even If height is correct. If your having abnormal tuning issues intermitantly lean or starving for fuel,lean on needle position bur 4 stroking on main jer
,flooding,4 stroking on leanest needle setting . Float height may need to be adjusted to suit your situation. Even if carb is somewhat level. Float height may need to be higher or lower than recommend in.some cases. These problems may also stem from - stuck Float needle,porous Float,clogged fuel inlet, clogged or debris in jet,clogged fuel filter,fuel line collapsed,excessive fuel leak,clogged petcock/sock in tank and vapor lock.o
2. Extreme drop in temperature (-30°-40° from correct tune) WILL LEAN MIX/Extreme rise in temperature WILL RICHEN MIX (+30°-+40° from correct tune)
3. Adding or removing air cleaner will richen or lean mix
4. +Altitude Wil richen m8x
5. Increasing fuel to oil ratio will lean mix. (Example from 40:1 to 20:1= leaner
6. Loose exhaust or leaking gasket will cause leaner conditions however will not affect idle
7 LEAN=HOT RICH=COOL but dirty
8. Excessive vibration can cause fuel to foam in carb causing lean mix
CONCLUSION
For the most part a smooth ride is a safe one for your motor. 4 stroking when cold and under light load/throttle input Is not only acceptable but recommended for a healthy motor. DO NOT RIDE WITH A LEAN OR RICH CONDITION. IT cause excessive wear or immediate damage. In extreme case total failure. If this guide hasn't properly setup your new rig or corrected your issue then get that gumout/carb cleaner and find that air leak or maybe you should consider an e bike... and become the constant butt of. Ya jokes! I'll have plenty of time to tell you all of them while it charges! Lol
