Carb Carburetor
Carb Carburetor
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![]() 1969 1970 1971 HONDA CB175 CB 175 CARBURETORS 69 70 71 CARBS CARB CARBURETOR SET US $91.00
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How to Improve Your Motorcycle's Start and Warm Up, Idling and Acceleration
AIR CUT-OFF VALVE
The Air Cut-Off Valve is an extremely important part of the fuel / air intake system that is frequently missed even by competent mechanics, most of whom are not even aware of its existence or how it functions. Over time, air cutoff valves will harden up, perforate and/or disintegrate leaving your motorcycle in a permanently lean, low RPM range (0-2200).
Most early model Honda, Kawasaki, Suzuki and Yamaha motorcycles use air cut-off valves. Every Honda CB650, CB750, CB900 and GL1000 has one, located in the air intake tube between the air cleaner box and the manifold. The GL1100 has four, located in the top air intake passage of each carburetor, and every GL1200 has one located in the plenum box below the air cleaner box similar to the GL1000.
These valves are "air blockers", along with the carburetor o-rings, serving to restrict air flow, increasing the fuel-air mixture ratio when the carb slides are in the lower RPM range, up to closed so that the machine will start and idle smoothly with virtually no choking and accelerate rapidly, with no stumble or hesitation.
When typical starting requires heavy and prolonged choking to keep the bike running, when stalling and hesitation occurs even while "warmed up" and when backfiring pops while the throttle is shut off while cruising, most people will start fooling with the air screws to try to overcome the problem, only making it worse along with reducing their gas mileage.
Running with dysfunctional air cut-off valves can cause severe engine damage or failure. When the valves are dysfunctional, the engine pulls nearly total air into the low RPM range through the carbs and on to the combustion chamber. The fuel-air ratio is extremely poor with pre-ignition long before the normal 38 to 40 degree firing point, generating an enormous amount of heat, with no power, which is trapped a longer period of time in the cylinder before the exhaust valve opens.
This heat goes mostly up through the cylinder head, gradually incinerating the head gaskets and allowing engine coolant (antifreeze) to seep into the engine. You can easily spot when you are in trouble by a puff of bluish-white or white smoke on first starting the engine. Don't leave it alone. Change the head gaskets immediately or you could take out your bottom end bearings, ruining the engine.
For those of you installing new exhaust systems, you will discolor your head pipes, either blue (lean state) or gold (rich state) if the signs are ignored. You an destain your pipes using Blueway or Blue-Off but be careful not to rub the chrome, just dab gently. These destaining compounds are usually found at a Harley dealer or Harley-oriented aftermarket shop.
Honda genuine pipes, like many Yamaha pipes, have a double wall for a portion of the head pipe which masks discoloration - but also masks a bad state of tune. Even if your pipes are original and still in good shape, don't think you're safe if your motorcycle has any or all of the dysfunctional air cut-off valve running and performing characteristics.
If your 1975 to 1987 Gold Wing is not getting 50 to 58 miles per gallon (20-23 kilometers per liter), you have one of the most obvious signs of trouble. It is likely your air screws have been backed out to try to overcome the effects of the poor running, stumbling, starting, stalling and quitting.
INSTALLATION GUIDELINES
Refer to your Clymer, Haynes or Honda Workshop manual for location and installation procedures.
Replace your air cut-off valve/s then resynchronize all four carburetors to the #3 carburetor vacuum level using a mercury carb sync tool (carb stick) or vacuum gauge synchronizer tool. The number 3 carb is the constant fixed flow carburetor set at the factory.
DO NOT attempt to set by ear or just by guessing as the results can be anywhere from pathetic to disastrous.
DO NOT deviate from the book settings of your Honda, Clymer or Haynes manual. Wiser people than all of us designed this very effective and efficient intake and carburetion system.
To further insure against any additional vacuum loss, replace your inexpensive carburetor manifold o-rings. Vacuum loss can occur there and mimic the effect of a bad air cut-off valve. Paste a new set in with vaseline and make sure they are sealed with an ether check.
© Saber Cycle®
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About the Author
Eugene Bileski represents over 46 years in the motorcycle trade as a past importer of Bridgestone, Ducati, Marusho, Norton and Yamaha motorcycles and is founder of Saber Cycle Honda Gold Wing Parts and Accessories at http://www.saber-cycle.com
Inexpensive air cutoff valves for Honda CB650, CB750, CB900, GL1000, GL1100 and GL1200 can be found on our website, in addition to the carburetor synchronizer tools and manuals referred to in this article.
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Carburetor Synchronizer $93.99 Emgo Carburetor Synchronizer Complete 4 carb kit: Vacuum gauges Hoses Adaptors Mounting plate Instructions |
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Carburetor Float Bowl $12.89 Carburetor Float Bowl for 50cc 4-stroke QMB139 engines. Carb Float Bowl |
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HSR42 Carburetor $337.99 Mikuni HSR42 Carburetor For the high-performance engine builder who needs a carb for specific custom applications Available in standard or highly-polished finishes |
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Carburetor Repair Kit for Solex Design by Omix-Ada $37.99 Carburetor repair kit for Solex design;L-head;For carb part #923806 |
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Walbro Carburetor $54.55 HP carb from Walbro: - Metering system and fuel pump integrated in the carburetor casting. - Can be delivered with or without choke. - High and low speed needles, idle needles, and idle adjust screw. - Proper function in any altitude. Bolt Hole Spacing: 31mm Venturi Hole Diameter: 15mm |
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Carburetor Repair Kit $23.99 K&L Carburetor Repair Kit Each carburetor repair kit from K&L contains all necessary gaskets, O-rings and jets to rebuild one OE carb **Note: Polaris - use with round slide VM34 Mikuni carburetor |
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Carburetor Vent Line $8.95 Moose Racing Carburetor Vent Line This quality made fuel line will not harden or crack Available in 1/8" i.d. Carb vent line comes in 5-foot lengths Choice of clear or black |
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Upper Carburetor Half $24.79 Upper Carburetor Body Half for 50cc 4-stroke QMB139 engines. Also known as the Upper Carb Body. Shop our wide assortment of scooter parts , gas scooters , electric scooters , and motorized scooters for sale. |
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Edelbrock 4- Barrel Carburetor Spacers $24.99 Provides Superior Heat Insulation,Ideal Roar Reducing Heat Transfer To Carburetor,More Plenum Volume,More Carb-To-Plenum Floor Distance |
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Itw Global Brands Itw Global Brands 14oz Carb& Choke Cleaner 800002231 $4.24 14oz carb& choke cleaner 14OZ CARB& CHOKE CLEANER Brand #: ITW Global Brands 800002231 UPC: 071948010758 Keywords: cleaner carb & choke carburetor |
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Itw Global Brands Itw Global Brands 16oz Carb& Choke Cleaner 800002230 $4.75 16oz carb& choke cleaner 16OZ CARB& CHOKE CLEANER Brand #: ITW Global Brands 800002230 UPC: 071948010697 Keywords: cleaner carb & choke carburetor |
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Performance Carburetor by Weber for Jeep $339.99 1983-88 Jeep XJ Cherokee;2.8L w/Rochester R2 E2SE carb;Linkage factory installed;Re-use your original air cleaner JEEP CHEROKEE (XJ) CHIEF LAREDO PIONEER 1984 1985 1986 2.8L (173) GAS Performance Carburetor by Weber for Jeep |
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2-Stroke Carburetor Prep Kit $7.93 Walbro 167, 603 and 668 racing carburetor prep-kit. HP carb prep kit for Walbro 167, 603, & 668 carburetors. Includes throttle cable bracket, swivel kit, spring, and 6mm nut. Note: Requires #12 drill bit, not included. |
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Economy Carburetor Repair Kit $17.99 Economy Carburetor Repair Kit Economy Carburetor Repair Kit Each kit contains all necessary gaskets, O-rings and jets to rebuild one OE carb Kits come with needle and seat if removeable on OEM Kit does not include main jets or pilot jets **Note: Picture may vary from actual bike specific kit |
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Carburetor Mounting Flange $21.99 Mikuni Carburetor Mounting Flange Genuine Mikuni Carburetor Mounting Flange that adapts your cruiser motorcycle, ATV, dirt bike, or street bikes spigot (sleeve) mount carb to flange mount manifolds. Clamp included Made from temperature resistant, synthetic rubber **Notes: Image is for reference only; actual product may vary Use diagram and measurment table (found in Multi View)?to verify flange measurements before ordering to ensure proper fitment. |
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Carb Insulator Gasket $2.97 Carburetor Insulator Gasket for 50cc 4-stroke QMB139 engines. Center Hole Diameter: 16mm Bolt Hole Spacing: 45mm |
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Trans-Dapt Carburetor Adapter $32.99 Holley Or Rochester 2 bbl. Carb To Quadrajet Manifold; 1.250 in. Casting Height; |
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1972-1979 Buick Skylark Carburetor Edelbrock Buick Carburetor 1400 $382.37 b 49-state legal not for sale or use in california cannot be shipped to california addresses /b performer series carb 600 cfm leak free operation smooth transition from part to full throttle change jets needles and seats or adjust floats on car without draining fuel sq-flange electric choke with egr includes prim. jet-0.086 sec. jet-0.095 metering rod-0.065x0.052. auto parts warehouse has extensive edelbrock carburetor catalogs.we are now offering free shipping on all edelbrock carburetor orders over $50.00. our secure edelbrock carburetor catalog is available every hour of everyday. shop with confidence for all your edelbrock carburetor needs. edelbrock carburetor are in stock and available today. save upto 60% off dealer price on your next edelbrock carburetor purchase. our online catalog contains a wide selection of the oem and aftermarket parts you need at unbeatable prices |
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HSR42 Smoothbore Carburetor Kit $539.99 Mikuni HSR42 "Smoothbore" Carburetor Kit Kits include the redesigned 42mm smoothbore carb in a natural finish Easier, faster installation using stock CV throttle cables Excellent throttle response, more power, improved acceleration and better gas mileage Order fewer part numbers to cover more applications Installation instructions and hardware included Everything needed for a complete installation Include performance intake manifold, rubber flange, 42mm carb, high-flow K&N filter, air cleaner cover, breather kit and hardware 84-89 models require the use of 90-95 Big Twin-style cables |
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HSR45 Smoothbore Carburetor Kit $611.99 Mikuni HSR45 "Smoothbore" Carburetor Kit Kits include the redesigned 45mm smoothbore carb in a natural finish Easier, faster installation using stock CV throttle cables Excellent throttle response, more power, improved acceleration and better gas mileage Order fewer part numbers to cover more applications Installation instructions and hardware included Everything needed for a complete installation Include performance intake manifold, rubber flange, 45mm carb, high-flow K&N filter, air cleaner cover, breather kit and hardware 84-89 models require the use of 90-95 Big Twin-style cables |
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TE2809 Sh .28 Carburetor $56.38 Carburetor |
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TE1809D1 Sh .18 Carburetor $41.34 Carburetor |
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110cc to 150cc 4-Stroke Carburetor $35.7 Carburetor with cable operated choke for 110 to 150cc vehicles. Used on Vertical Cylinder, air-cooled 4-stroke engines commonly found on Chinese dirt bikes, ATVs, mini-choppers and dune buggies. Cable perated choke located on left side of carb Bolt Hole Spacing (engine): 48mm Engine Opening Diameter: 26mm Air Filter Mount: 39mm |
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Performance Carburetor by Weber $289.99 1980-83 CJ;2.5L w/Rochester R2 E2SE carb;Linkage factory installed;Includes chrome air cleaner |


US $175.00































































































