Filed Under (Triumph) by admin on 29-10-2010
Jets: These are made in various sizes ranging from.099 inches to.1875 inches, the larger sizes being used only for racing or very high performance engines. The two sizes most commonly found on production cars are the.090 inch and the.100 inch. The size of the jet will be found stamped on the jet head. The figure “nine”wilt indicate that it is the.090 inch and the figure “one”will indicate the.100 inch jet. When tuninga production car the jets size should be checked to make sure that it is of the size recommended by the manufacturers. Centering of Jet: If for any reason, the jet assembly has been removed, it will be ne cessary to recenter the jet. First, remove the clevis pin at the base of the jet which attaches the jet head to the jet operating lever. Withdraw the jet completely and remove the adjusting nut and spring, then replace the adjusting nut, without its spring, and screw it up toits highest position. Slide the Set into position until the jet head is against the base of the adjusting nut. When this has been done, find out if the piston is perfectly free by lifting it up with the finger and allowing it to drop. If the piston is not entirely free, slacken the jet screw and manipulate the lower part of the assembly, including the projecting part of the bottom half of the jet bearing, adjusting nut, and jet head. Make sure that this assembly is now slightly loose. The piston should then rise and fall quite freely as the needle is now able to move the jet into the required central position. The jet screw should now be tightened and a further check made to determine that the piston is still quite free. When complete freedom of the piston is achieved the jet adjusting nut should be removed, together with the jet, and the spring replaced. Experience has shown that a large percentage of carburetors, which have given trouble has been due to the incorrect centering of jets. Jet Needles— These are made in a great variety of sizes, probably now well over two hundred and fifty, and each type of engine hasaneedlethat has been selected, after very careful tests have been carried out, to give the best all-round performance. Most manufacturers actually give three alternative needles for each type and size of engine, these needles clearly being listed by the manufacturer “Standard”, “Rich”or”Weak”and before tuning is started the needle, which is marked on the shank should be checked against the manufacturer’srecommendation to make quite sure that the right needle is fitted; this is most important.
Filed Under (KTM) by admin on 12-11-2010
Repair manual KTM 250 / 300 / 380 Art No 3206004 -E 2-2C main jet jet needle jet needle air control screw idle adjusting screw idle jet throttle valve Idling range A Operation with closed throttle valve. This range is influenced by the position of the air control screw 1 and the idle adjusting screw 2 . Only make adjustments when the engine is hot. To this end, slightly increase the idling speed of the engine by means of the idle adjusting screw. Turning it clockwise produces a higher idling speed and turning the screw counterclockwise produces a lower idling speed. Create a round and stable engine speed using the air control screw (basic position of the air control screw = open by 1.5 turns). Then adjust to the normal idling speed by means of the idle adjusting screw. Opening up B Engine behavior when the throttle opens. The idle jet and the shape of the throttle valve influences this range. If, despite good idling-speed and part-throttle setting, the engine sputters and smokes when the throttle is fully opened and develops its full power not smoothly but suddenly at high engine speeds, the mixture to the carburetor will be too rich, the fuel level too high or the float needle is leaking. Part-throttle range C Operation with partly open throttle valve. This range is only influenced by the jet needle (shape and position). The optimum part-throttle setting is controlled by the idling setting in the lower range and by the main jet in the upper range. If the engine runs on a four-stroke cycle or with reduced power when it is accelerated with the throttle partly open, the jet needle must be lowered by one notch. If then the engine pings, especially when accelerating under full power at maximum engine revs, the jet needle should be raised. If these faults should occur at the lower end of the part throttle range at a four-stroke running, make the idling range leaner; if the engine pings, adjust the idling range richer. Full throttle range D Operation with the throttle fully open (flat out). This range is influenced by the main jet and the jet needle. If the porcelain of the new spark plug is found to have a very bright or white coating or if the engine rings, after a short distance of riding flat out, a larger main jet is required. If the porcelain is dark brown or black with soot the main jet must be replaced by a smaller one. mixture too rich: too much fuel in proportion to air mixture too lean: not enough fuel in proportion to air 1 2 OPERATING RANGES OF THE CARBURETOR 2-3C Carburetor adjustment Basic information on the original carburetor setting The original carburetor setting was adapted for an altitude of approx. 500 meters (1600 ft.) above sea level, and the ambient temperature of approx. 20°C (68°F), mainly for off-road use and central European premium-grade fuel (ROZ 95 MOZ). Mixing ratio 2-stroke motor oil : super fuel 1:40 – 1:60. Basic information on a change of the carburetor setting Always start out from the original carburetor setting. Essential requirements are a clean air filter system, air-tight exhaust system and an intact carburetor. Experience has shown that adjusting the main jet, the idling jet and the jet needle is sufficient and that changes of other parts of the carburetor will not greatly affect engine performance. RULE OF THUMB:
Filed Under (Mikuni) by admin on 31-10-2010
Intake Manifold: 1. Install MAP sensor in Mikuni manifold (Twin Cam only). 2. Attach the Mikuni manifold to the engine. Align the manifold before tightening the bolts. The flange surface of the Mikuni manifold should be parallel with the front of the engine’s cam cover. Use a level or angle meter to check this. Tighten the manifold bolts. 3. Attach the rubber flange to the Mikuni manifold with the furnished 5/16″x3/4″ bolts and washers. Choke Cables: Mikuni & Harley-Davidson Route the cable with largest radius bends possible. Check the cable for free-play after installation. If there is no free-play, the engine may run rich and deliver poor performance or low fuel mileage. Harley Cable (Twin Cam Kits: 42-19, 45-4) : 1. Remove the Harley choke cable from the stock carb. 2. Remove the spring and plunger from the cable. 3. Remove the spring and plunger from the Mikuni. 5. Install the Mikuni spring and plunger onto the Harley choke cable. Change nothing else; be sure to use the Harley plastic nut, not the Mikuni nut (See Figure 1). Total Kit Installation Instructions The HSR series carburetors are precise yet durable instruments; however, like any other piece of fine equipment, they require correct installation and reasonable care to assure optimum performance and long life. Extra time spent during installation will pay off in both short and long term performance and reliability. This Mikuni HSR carburetor kit is designed to be a bolt-on application, and as such, is set-up and jetted properly for most applications. However, since Harley-Davidson motors are often highly modified, alternate tuning settings may be required. The Mikuni Tuning Manual helps make jetting alterations and adjustments an easy matter. NOTE: Carburetor Kits not designated as C.A.R.B. exempt, are not legal for motor vehicles operated on public highways in the state of California, or in any other states and countries where similar laws apply. WARNING NOTE: NOTE: WARNING CAUTION NOTE: NOTE: TK-2 6. Install the new assembly into the Mikuni carburetor. Be careful to only gently tighten the plastic nut. 7. Loosen the knurled plastic friction nut behind the choke knob and check for free-play (see Figure 2). Figure 1: Harley nut with Mikuni spring & plunger Figure 2: Choke cable adjustments Mikuni Cable (Evo Kits: 42-8, 45-2 & 45-3) : 1. Remove nut, spring and plunger from the Mikuni. 2. Install the nut, spring and plunger onto the cable. 3. Install the assembly into the Mikuni HSR carburetor. Be careful to only gently tighten the plastic nut. 4. Check for free-play. Adjust the cable as necessary. An optional choke cable mounting bracket is included in the Evo kits for custom installations. Carburetor Installation: 1. Insert the carb fully into the rubber flange, align with engine and tighten the clamp. 2. Slip the fuel hose onto the carburetor’s fuel fitting and secure with the enclosed hose clamp. NOTE: Some Twin Cam installations may require removal of a small amount of fin material from the cylinders to clear the float bowl. Throttle Cables The HSR carburetor uses stock 1990 and later Harley- Davidson cables. However, if your Harley is fitted with some other carburetor, you may need to purchase a set of cables. See your dealer for the correct cable set. 1. Route the throttle cables with large radius curves and so they do not interfere with other components. 2. Screw the cable adjusters together to make them as short as possible. 3. Connect the “close” cable first (see Figure 3). 4. Install the “open” cable next (see Figure 3). 5. Adjust the opening cable until the slide can be opened fully. Snug the adjuster lock nut. 6. Turn the handlebar to the right and adjust the throttle free-play with the closing cable adjuster to approximately 1/8″ (see Figure 4)
Filed Under (Honda) by admin on 27-12-2011
To install this needle and jet kit: • Remove carburetors from the engine per Yamaha shop manual procedures. Note: Always perform internal carburetor work in a clean area. • Remove the vacuum slide from each carburetor. • Remove the OEM needle, spacer and washers, noting order of assembly. (Note; the washers are used as shims to raise the needle, each is equivalent to ½ clip position, use these to fine tune the needle) • Counting from the top to the bottom, install the new Baron needle clip on groove #4 of the replacement Baron adjustable needles. The top is the blunt end of the needle. • Reinstall the OEM spacer and washers as shown in the figure below. • Reinstall the vacuum slides along with the diaphragm spring and reattach the diaphragm covers Note: Verify that the slides maintain their full range of movement! • Drain the fuel from the float bowls and remove the bowl covers. • Remove the OEM main jets and replace them with Baron’s supplied Mikuni main jets. Install the “base setting” main jets as indicated above. NOTE: V-Star 1100 carburetion runs staggered jetting! Make sure the front cylinder’s carburetor gets the larger main jet (numerically), and the rear cylinder’s carburetor gets the smaller main jet . Important! Extra jets have been included in your kit. These will help you fine-tune the carburetors for changing conditions. These conditions include climate and weather patterns in your area as well as exhaust equipment on your motorcycle. Barons determines the jet and clip recommendations that best suit your average riding conditions based upon information supplied to us at the time of your order. Changes in weather, altitude or modifications to your exhaust system may require jets other than those supplied. • Thoroughly clean the inside of the float bowls prior to reinstalling them. 311 #1 Industrial Way – Fallbrook, CA 92028 – USA Phone: (760) 731-1200 Fax: (760) 731-1284 E-mail: email@example.com Website: www.baronscustom.com Included in this kit: (4)Mikuni main jets #107.5, 110, 112.5, 115, (2) titanium needles, (2) clips, (8) cap-head allen screws Tools required: 3-4-5 mm allen wrenches, 10&12 mm sockets, 10mm end wrench, phillips & flat screwdrivers, pliers, drill. Revision 4.0 • Reassemble the carburetors by reversing the order of above steps. Use the new supplied cap head Allen screws in place of the OEM Phillips head screws for the float bowls. • Locate the fuel mixture screws – they will either be a screw head or a brass plug. If it is a screw head, skip to step c . If you see a brass plug with a small hole in the center, proceed as follows: a. With a 5/32″ drill bit, carefully and slowly drill through the fuel mixture plugs
Filed Under (Yamaha) by admin on 10-11-2010
1. Remove the vacuum slide from the carburetor. 2. Remove the OEM needle, spacer and washers, noting order of assembly. 3. Counting from the top to the bottom, install the new Baron needle clip on groove #4 for 04-07 models and on groove #5 for 99-03 models of the replacement. NOTE: Baron adjustable needle – The top is the blunt end of the needle. 4. Reinstall the OEM spacer and washers as shown in this diagram. 5. Reinstall the vacuum slide along with the diaphragm spring. 6. Reattach the diaphragm cover back and tighten screws. NOTE: Verify that the slide maintains its full range of movement. 7. Drain the fuel from the float bowl and remove the bowl cover. 8. Remove the OEM main jet and replace it with a Barons genuine Mikuni main jet. Install the correct main jet as indicated in JET SELECTION area above on this page. Our install guides provide a basic outline on the proper installation of our products. Further tuning and/or fitment may be required. Page: 2 BA-2420RD NEEDLE/JET KIT – Yamaha Road Star (99-07) 9. Thoroughly clean the inside of the float bowl prior to reinstalling it. 10. Reassemble the carburetor by reversing the order of step #1 through step #10. Use the new cap head allen screws in place of the OEM phillips head screws. 11. Locate the fuel mixture screw – it will either be a screw head or a brass plug. If it is a screw head, skip to step #11c. 11c. If you see a brass plug with a small hole in the center, proceed as follows: With the drill bit, carefully and slowly drill through the fuel mixture plug. CAUTION: The fuel mixture screw is located directly beneath this plug. Be prepared to stop the drill and remove the bit the instant you break through the plug. Insert the self-tapping sheet metal screw into the drilled hole and remove the plug. With air/fuel screw now accessible, use a flat blade screwdriver to turn the screw clockwise until it seats, then carefully turn it counter-clockwise 3 1/2 turns. Refer to step #16 for assistance in fine tuning the setting of the air/fuel adjustment screw. 12. Reinstall the carburetor. We strongly suggest that you attach the throttle cables prior to mounting to intake manifold. 13. Reconnect the fuel line, ensuring the clamp is firmly in place. 14. Reinstall all vent hoses and electrical connectors that were previously removed, checking for any obstructions or blockage. 15. Reinstall the OEM air filter assembly or, if you are installing our Big Air Kit (BAK), follow the instructions that accompany that kit, then continue with next step. NOTES: When the BAK is installed, the vent hose that terminated on the rear of the OEM airbox can be relocated in any safe position that does not kink or pinch it. It is important to verify proper throttle operation before starting the engine.