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Thread: Big Bore Conversion Manual

  1. #1
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    Big Bore Conversion Manual

    Removing the gas tank and bodywork
    In a clean and well-lit area of your garage, clear a workspace. Allot of body work has to come off to do a full kit, and you should lay the parts out as they are removed. If possible, lay the bodywork on carpet or some other non-abrasive surface to prevent as much damage as possible to the finish of your plastic. Start by removing the front seat which comes off with the key.
    VERY IMPORTANT
    Turn the fuel tap (fuel petcock) to the OFF position.
    Only proceed with a cold engine and a well-ventilated area

    Next, using a 5mm Allen key wrench, remove the bolt and conical spacer located in the top front of the fuel tank near the steering stem. Next, raise the tank on its back hinge and remove the fuel line from the fuel tap (fuel petcock). Next, lower the tank back to its original position. Next, using a 10mm wrench and 10mm socket, remove the bolt at the rear of the fuel tank which secures the tank at the back side (see picture 2). Now carefully remove the fuel tank and rest it in a position which will not damage it. An old tire on its side works very well for this.
    Now you only have twenty five fasteners left before all of the necessary bodywork will be off. Using a 4mm Allen key wrench, carefully remove all of the bolts which secure the fairings. Do this one side at a time. Start with the left side, first removing the three bolts which secure the mini panel behind the side stand (kickstand). Next, remove the two bolts at the bottom of the side fairing followed by the one in the middle of the fairing. Next, the four bolts around the point where the upper meets the side fairing. Now, look behind the front wheel and remove the 4 bolts holding the chin fairing and the bottom of the upper fairing to the side fairing. Caution at or near this point, the fairing may want to fall off, hold it securely. The turn signal does not need to be removed, just disconnect the wires. As you pull the side panel away from the bike, you just pull the connectors apart that power the turn signals. The chin fairing will now come out with the removal of four more bolts. Now the right side panel, remember to take out the screws that hold in the fresh air duct and the rear of the panel. This panel comes off in the same fashion as the other, just remember to unplug the turn signal.
    At this point, you should have a pile of twenty-five fairing screws, one long tank hinge bolt, and the bolt & washer combo that secures the front of the tank.
    Removing the upper front fairing and tail section is not required for any part of a RS50 hop-up
    Reassembly is the reverse of the process.
    Reassembly tips:
    Do the job one step at a time in the reverse order of the disassembly process

    Before tightening any of the bolts completely, make sure all of the bolts are installed and the bodywork is all lined up properly.
    Do not forget to re-install the fresh air duct on the right side.


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    Administrator Ted / AF1 Racing's Avatar
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    Intro:
    Both the cooling system and the gearbox oil will need to be drained to complete the install of the big bore kit. If you are not replacing the clutch, then you will not have to drain the gearbox oil. Warning, you must replace the clutch with a Barnett clutch kit, if you are actually going to ride your big bore bike aggressively at all. The stock clutch can be smoked in one afternoon and a Barnett can last a very long time. We like to drain the coolant first and the gearbox oil second.
    Draining the coolant:
    To drain the coolant, you first remove the filler cap on the left side dash panel, and then remove the drain bolt on the water pump (see picture 1). This is the only bolt on the water pump that has a sealing gasket on it. Blue coolant will now start running all over the place if you don’t have a good sized catch pan in place. Let the coolant drain for a minute or two to ensure that most of the coolant is gone from the system.
    Draining the gearbox:
    Now remove the gearbox oil drain bolt from underneath the motor and let it drain for at least 5 minutes to get it all out. This is a 13mm gold colored bolt (see picture 2). Now that the fluids are out of the motor, the fun part can get underway.
    Refilling the coolant:
    After the big-bore conversion is done, you need to refill the coolant system. First, ensure all hose clamps are secure, and then replace the coolant drain screw. Fill through the reservoir cap located on the left side top fairing. Now grab different coolant hoses and squeeze them by hand. This will help get rid of any air trapped in the bends and on the walls of the rubber coolant hoses. The level will go down again. Repeat process until level stays constant. If you are starting the motor immediately after these steps, make sure to check the level again after it has run for a couple of minutes and again after the first ride. For racers only, use straight distilled water and a Water Wetter-type product. For street use, we recommend a 50/ 50 mix of distilled water and phosphate-free coolant. For extremely hot climates, a 75% water and 25% coolant mix will carry away more heat. Warning: For those running straight water, remember to drain it before the winter. Freezing water can and will crack crankcases (think $$$$).
    Refilling the gearbox:
    Once the Barnett clutch conversion is done, you must refill the gearbox with 75W90 full synthetic gearbox oil. First, remove the oil level screw in the middle of the side cover. It is a Phillips headed screw (see picture 3). Also, remove the fill plug. Replace the oil drain plug. Begin filling the gearbox. Stop when you see oil drip out of the level screw. With the bike completely level and upright, let all the excess oil drain out. Replace level screw and fill plug. DO NOT OVERFILL THE GEARBOX


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  3. #3
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    Removing the airbox:
    Now that the tank is off the next step is to remove the stock airbox and carburetor. First locate the clamp that holds the airbox to the carburetor itself. Using a flat blade screwdriver (a long one) loosen this clamp a few turns (see picture 1). Now locate the bolt at the rear top of the airbox. This M6 bolt has an 8mm hex head. Remove this bolt and that is all of the fasteners that hold the airbox to the carburetor and to the chassis. Firmly grab the airbox and pull straight up on it. This should allow it to separate from the rest of the assembly.
    Removing the carburetor:
    The first step in removing the carburetor itself is to remove the two bolts that hold the slide in place with a flat blade screwdriver (see picture 2). This is the point where the throttle cable goes into the carburetor. Once the two screws are removed, the slide assembly will come straight up and out of the stock carburetor. You can now remove the cable from the slide assembly. Next, loosen the clamp bolt that holds the carburetor onto the manifold. Once this is loose, the carburetor and all associated vent lines can be pulled out of the chassis. Next, remove the fuel line from the stock carburetor. This will be used on your aftermarket carburetor, or you can get a new fuel line that incorporates a filter.
    Removing the throttle cable:
    Now is the time to remove the throttle cable from the splitter junction. This is a simple process, but many people get confused at this point. First remove the two M4 Allen bolts that hold the oil injection pump cover onto the motor (see picture 3). Now you will see where the second cable from the splitter junction terminates. This is the oil injection pump cable. It moves with the throttle cable to allow more oil into the case when the throttle is opened. Carefully rotate the arm that the cable terminates in to the rear of its travel (see picture 4). You will now be able to remove the cable end from the arm. The junction splitter is made in two halves so you can remove the cables from it. The top cap is pressed on pretty well so some force will be required to break it loose. Once loose, you simply push both cables and the piston upwards. They ride in a small groove inside the junction. Remove the throttle cable from the junction splitter. If you are going to premix from now on, leave the oil pump cable disconnected. If you are going to continue to run the oil injection system, then take note of how the cables were routed and how the ends fit in their respective places. When reinstalling the cables, hook up the oil pump cable only after you are finished reinstalling cables inside the splitter junction.
    Removing the manifold:
    Removing the manifold is accomplished by removing the four M6 Allen bolts with a 5mm Allen driver and taking off the two small hoses that serve to heat the stock manifold (see picture 5). These hose clamps can be easily removed with a set of wire dyke pliers, and then the hoses must be pulled free. Take note at this point that two of these bolts hold stuff in addition to the manifold. The one in the top left of the manifold also holds three grounding wires that must be reconnected in order for your bike to run. The one in the bottom right holds the clutch cable in place. Take a careful look to see how these are installed. These both will need to be reinstalled on your new manifold. Once the four bolts are removed, the manifold should be free to come off. Sometimes the gasket will cause it to stick and some tapping with a rubber mallet may be needed.
    Removing the reed cage:
    At this point, you may either be replacing the entire reed cage, the reeds themselves or just removing the restrictor. You should see the backside of the reed cage at this point. It has a small opening that matches with the exit of the manifold. To remove the cage, try first to simply pull it out of the case with finger pressure. If that fails, resort to careful tapping and prying. This small opening is the reed cage restrictor (see highlighted picture 6). It will only restrict your motor, if you are running a carburetor larger than the stock 12mm. For a stock carburetor, the restrictor is not a bad thing, since it smoothes the transition of air into the reed cage. For all the big carburetor users, it must come out.

    The easiest way to remove the restrictor is to first remove the reeds and reed stoppers (be careful), and attack the restrictor from the front side (see picture 7). Hold the cage firmly and use a sharp Phillips screwdriver bit to remove the four screws that hold the reeds down. Once these screws are out, carefully pull the reeds away from the cage, and lay them down on a clean surface in the same way they were positioned in the cage. This is important, as reeds are usually curved to a very small extent to aid in their sealing. They need to be fitted in the same way they were originally fitted. With the reeds removed, take a screwdriver of the appropriate size and push on the restrictor from the back side. It will require some force to make it come out. Be careful not to let the tool push against anything but the restrictor (see picture 7). You do not want to damage the sealing surfaces of the reed cage. Carefully reinstall the stock or carbon reeds and the reed stoppers.



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    Administrator Ted / AF1 Racing's Avatar
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    Removing the stock exhaust:
    Before we can remove the cylinder to install the big bore kit, the exhaust system must be removed.
    This is a simple process, the pipe is held in only three places. The front of the exhaust is held on by two springs which are easily removed by using a proper spring puller tool (see picture 1). These tools are available at auto parts stores for working on drum brake set ups and are usually very inexpensive.
    The middle and rear of the exhaust system are held on by M8 bolts which are removed by using a 6mm Allen key wrench. The middle bolt is underneath the bike (see picture 2). The rear is the exhaust hanger bracket. These bolts go into rubber dampeners, but do occasionally need to be held from the back side by a 13mm box end wrench. Try not to damage these dampeners, as they will keep your pipe from stress cracking as time goes on.
    Now that all the fasteners are removed, the exhaust will still be attached to the cylinder because it slips in to the cylinder. Pull the exhaust away from the cylinder and twist it at the same time, this part can seem like it will take forever, but it will eventually come loose.
    Reinstallation of your new pipe will follow the same procedure in reverse.
    Tip: When installing a new pipe, it helps to lube the header pipe with a bit of two stroke oil to allow it to easily slide through the o-ring inside the cylinder.

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    Administrator Ted / AF1 Racing's Avatar
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    Removing the cylinder head:
    With the coolant completely drained and the exhaust removed you are now ready to proceed.

    This is really the easy part. Using a set of pliers, remove the OEM hose clamps that go to the large and small hoses attached to the cylinder head (see picture 1). Now, just twist and pull on the hoses until they come off. Some water will drain at this point, which is fine. Next using a proper 13/16” spark plug socket remove the stock spark plug (circled green in picture 1). Now using a deep-well socket, remove the water spigot, which is where the small coolant hose attached to (see picture 2). If you are using a Top Performance big-bore kit, you will reuse this part, so set it aside. If you are using any other big-bore kit, this will be a leftover part.

    Next, using the proper size deep-well socket remove the temperature sending unit from the stock head (circled red in picture 1). The temperature sending unit is the only part of the head that has an electrical wire running to it. Now that the head is bare, you now need to remove the four nuts that hold down the head and cylinder to the crankcase. Note, sometimes the entire stud comes out instead of the nut alone…this is not a big deal, you just have to locate a stud installer tool or use a pair of M7 nuts to re-install the cylinder stud. With the nuts removed you simply pull up on the head and it will come off. Make sure to collect all of the four small and two large o-rings (see picture 3).


    Removing the cylinder:
    Try to soak up any remaining coolant in the water jacket of the cylinder. You really do not want a ton of water going into the crankcase. Next, pull up on the cylinder itself, it should slide off with some very light effort. Try to pull it up as even and square as possible (see picture 4). The friction you feel is the piston rings pressing on the bore, which is completely normal. Also, keep a hand underneath to catch the connecting rod, so it does not bang against the crankcase when the cylinder comes off. After the cylinder is off, place a few clean rags into opening in the crankcase. You DO NOT want anything falling into the crankcase.


    Removing the piston and wristpin:
    The piston in held onto the connecting rod by the wristpin and two small circlips (highlighted in picture 5). The circlips fit into small grooves in the piston, and keep the wristpin from falling out. Using a pair of needle nose pliers grab the tab on the circlip that retains the wristpin and gently pull on it (see picture 5). It helps to give the pliers a twisting motion too, as if you are tightening the circlip onto itself. Make sure you have clean rags stuffed in the crankcase, just in case, you drop the circlip. You DO NOT want it to fall into the motor.

    With just one circlip removed, you can then use a properly sized socket and extension to push the wristpin out from the other side (see picture 6). There is a special tool for this, but the wristpins on the RS50 come out very easy. Hold the piton very firmly with one hand while removing the wristpin. You do not want to put any lateral strain on the connecting rod and big-end bearing. The piston will now come off of the connecting rod. You will also notice at this point, the small-end bearing (see picture 7). You can either replace it at this time or simply re-use it. Finally, make sure to remove all traces of base gasket from the top of the crankcase.

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  6. #6
    Administrator Ted / AF1 Racing's Avatar
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    Removing the case cover:
    The gearbox oil and coolant must be drained before proceeding (see Step 2). The oil pump cable can also be moved out of the way (see Step 3)
    The case cover gasket can be reused several times, and only needs to be replaced, if it is torn. Remember, over-tightening the bolts is the leading cause of gasket failure.
    It is also recommended to let your new clutch friction plates and steel plates soak in clean gearbox oil for 15-20 minutes before installation. The friction plates need to absorb a little bit of oil before use. Now would be a good time to start this.
    To remove the case cover, remove the eight bolts colored red in picture 1. Remember, the bolt circled blue was the coolant drain screw (see picture 1). The main coolant hose, and the inlet / outlet hoses for the oil pump can remained attached.
    Pull the side cover off by pulling straight out on it. It can hang out of the way by the coolant hose with no problem. Notice the two case cover location pins. Do not lose these.
    You will now see four Phillips screws with clutch springs under them in the center of the clutch hub. Remove these four screws and four clutch springs (see picture 2). The clutch center hub can now be removed. You can then start to remove the old clutch friction plates and steel plates. You will remove a total of four friction plates and three steel plates. Throw the stock frictions, steels, and springs away, as they are totally worthless.
    Begin replacing the friction and steel plates with the Barnett ones that have been soaking in fresh gearbox oil. Start with a friction plate, then a steel, alternating between them until you are done. The clutch pack will look like...
    Friction--Steel--Friction--Steel--Friction--Steel--Friction
    Place the center clutch hub back onto the clutch basket. Note, the clutch hub can only go on one way. Line up the arrow on the clutch hub with the dot on the clutch basket (see picture 4). Using the new stiffer clutch springs, replace the Phillips screws that hold the clutch hub on. Torque the four Phillips screws snugly by hand to roughly 3-5Nm.
    Now would be a good time to check your overall clutch adjustment. With the cable still attached under the carburetor, squeeze the clutch lever. If it needs major adjusting, this is done by the center clutch hub nut and screw (see picture 5). Minor adjustment can be done on the handlebar. If for some reason, your clutch ever just totally fails, 99% of the time, this locknut has come loose, and simply needs re-tightening. We like to double check that this screw and locknut are secure at this point. The locknut is torqued to 26-28Nm.
    You are now ready to reinstall the case cover. Take a mental picture of all the gears on the case cover that need to line up with gears inside the motor. The case cover needs to go straight on, and should go one with no effect or force. If it is not going on, try rotating the plastic gears to better line them up. Forcing the cover on can damage the gears. One of which, drives the water pump (not a good idea to damage that). You will also have to line up the gasket with all the bolt holes. Take your time and be patient during this step. It can take a while to properly line up everything. Torque all the bolts to 10-12Nm in a criss-cross pattern (i.e., do not go in a circle). The one long bolt can only go back in one spot (the most forward bolt on the water pump is is the long one.
    Do not forget to refill the gearbox with 75W-90 full synthetic gearbox oil and the coolant before operating.
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  7. #7
    Administrator Ted / AF1 Racing's Avatar
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    Introduction:
    Steps one through five must be done prior to proceeding. Note, it does not matter if the gearbox oil is drained oil filled. Begin by laying out all the parts on a clean dry surface (see picture 1). You should have at the very least a big-bore piston, piston ring(s), a wristpin, two new piston circlips, a new base gasket, and a new head gasket.
    Preparing the cylinder head:
    Start by preparing the new cylinder head. First, put a very light coating of gasket sealer on the temperature probe and thread into the new head. Snug tightly. If you are using a Top Performance big-bore kit, you need to also install the small water spigot that you removed from the stock cylinder head (circled blue in picture 2). The next step is installing the original stock thermostat on the new cylinder head. Simply unscrew the two Phillips screws and reinstall on the new head.
    VERY IMPORTANT....Notice the bleed hole in the flange (see picture 3), locate the thermostat in a position that allows fluid passage. It will appear like it is only 50% open, and this is perfectly normal.
    Preparing the piston and cylinder:
    Start by determining which way the ring goes. Every piston ring will have a stamp mark near the ring gap. It is usually a stamped "N" or "T". This MUST be installed facing upwards (see detailed picture 4). Also, locate the "locating pin" in the piston groove. The ring gap will go here.
    To install the piston ring, slip one end of the ring into the piston groove, and work towards the other end. The ring gap will be centered over a locating pin in the piston groove. Try to open the ring as little as possible. Be very careful during this step. The ring and piston will eventually be going up and down over 11,000 times per minute.
    Now would also be a good time to learn about the arrow mark on the top of the piston. This always points towards the exhaust port. Since the exhaust exits out the front on the RS50, the arrow will be facing forward in the bike.
    Next, install one circlip into the piston. It does not really matter which one.
    The cylinder preparation consists of installing the exhaust o-ring into the exhaust port (see picture 5). It rests in a small groove in the exhaust port. Applying two-stroke oil to the o-ring will aid exhaust installation later. Lubricate it well.
    We also like to coat the cylinder walls with two-stroke oil as well. Rub some oil all around the walls with your finger. You can not really over-oil it.
    Installing the piston:
    Start by thoroughly and heavily oiling the small-end bearing. Also, thoroughly oil the wristpin. With the piston facing the correct direction (see above), slide the piston over the connecting rod. Insert the well-lubed wristpin through the piston with your fingers. Finally, install the second circlip.
    Now is a good time to double check that both circlips are fully seated in their respective grooves in the piston. You do not want them coming out!!!
    Installing the cylinder:
    Start by installing the new base gasket. Note, it can only be installed one way.
    The next few steps are probably the hardest of all. It is VERY important that they are done correctly. The job is easiest, if you place the crank and piston at top dead center (TDC). In other words, pull the piston up as high as it will go out of the crankcase. The bike must be in neutral.
    To start, you are going to have to fully compress the piston ring in order to install the cylinder over it. You are also going to have to make sure the ring gap is located on the "locating pin" in the piston groove (see close-up picture 6). Squeeze the piston ring between your thumb and first finger. With the other hand lower the cylinder over the piston. Once the piston is inside the cylinder a little way, it should lower with VERY LITTLE effort. DO NOT force it down!!! Try to lower the cylinder down evenly and squarely. If it does not go on easily, one of two things is happening. Either the ring gap is not centered on the "locating pin", or you are not fully compressing the ring during the cylinder installation process. This job maybe the easiest with two people. One person is in charge of compressing the ring and locating the ring gap, while the other person slowly lowers the cylinder onto the studs (see picture 7).
    Push the cylinder down fully onto the base gasket.
    Installing the cylinder head:
    Start by installing all of the head gaskets. On the Top Performance kit, one small o-ring is installed over each cylinder stud. The Malossi kit has these small o-rings integrated into the inner head gasket. It should be obvious how the inner and outer head gaskets are arranged. Do not forget the outer head o-ring, which seals the coolant inside the cylinder cooling jacket. Lower the new cylinder head onto the cylinder studs and ensure that all o-rings are seated properly. Install the washers and the cylinder head nuts (see picture 8). Initially torque all four nuts to 10Nm in a criss-cross pattern. Finally, torque them to 14-16Nm. It is important to torque them in stages like this to insure flat and even pressure. Install the spark plug and torque to 20-25Nm. Reinstall the big coolant hose on the top of the head. Use a new hose clamp. The small hose comes from the T-fitting on the right side coolant hose. On Malossi and other kits with no small hose connection on the cylinder head, special steps must be taken. A straight hose-to-hose connector will have to be obtained from an auto parts in order to remove the T-fitting from that radiator hose. We do not re-install the hoses for the carburetor manifold plumbing.

    Note:
    If you do not feel comfortable with these steps, please seek the advise of a professional. Anyone with 2-stroke dirt bike experience would be more than qualified to help.




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  8. #8
    Administrator Ted / AF1 Racing's Avatar
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    Introduction:
    At this point, you should have removed the airbox, the old carburetor, the manifold, the reed cage, and the old throttle cable. It is also a good idea to de-restrict the stock reed cage (see step 3 and picture 1). Do not install the new throttle cable on the carburetor at this time. The carburetor should be disassembled to the stage as seen in picture 6. The slide needs to be out of the carburetor body. There is a specific order that the carburetor install must proceed. If your manifold (Mikuni 24mm kit with 19mm manifold) has a mysterious hole in it, this is where the oil injection spigot goes. The old oil injection spigot must be removed from the old 12mm carburetor. It is just press-fit in. Use some gasket sealant on it and install it in the 19mm manifold. Lightly tap into place with a metal hammer. If you plan to run pre-mix only oiling, then you must come up with a way to block-off the oil injection spigot. It cannot leak air. Also remember, carburetor settings differ greatly between oil injection and pre-mix.


    Installing the reed cage and manifold:
    Re-install the reed cage, and bolt on the new manifold (see picture 2). Be sure to install the ground wires to the top left bolt, and the clutch cable holder to the lower right side bolt.


    Throttle Cable Installation:
    To install the new throttle cable, first the oil pump must be disconnected (see step 3 and picture 3). Then the cable splitter can be pulled apart. Install the new throttle cable into the splitter (see picture 4). Loop the cable ends into their respective slots inside the junction block (see picture 5). Close the cable splitter. You can now re-install the oil pump cable (see picture 13) back onto the oil pump. To continue installing the carburetor, first the carburetor top must be installed on the cable (see picture 7). Use all the supplied rubber boots, as this can be a source of an intake air leak.


    Throttle Cable to Carburetor Slide Installation:
    With the e-clip installed onto the needle, install the needle into the middle hole in the carburetor slide (see picture 8). Next install the carburetor slide spring over the throttle cable. Pull the cable end through the middle. With your hand or carefully with a pair of pliers, hold the spring compressed and grab the free cable end. Next, install the white needle hold down part (spring perch) over the free cable end. Put the free cable end into the slot in the slide body (see slot in picture 8). Slowly release the spring tension. Make sure the plastic part is fully seated. The finished result will look like picture 9. The order of the parts threaded onto the throttle cable are the carburetor top, gasket (small o-ring on Dell-Orto 21mm and a paper gasket on a Mikuni 24mm), slide spring, spring perch, and finally the slide.


    Finishing Up:
    Carefully install the slide into the carburetor body. It can only go in one direction. Be careful with the needle. It needs to be inserted into the emulsion tube (see picture 10). Do not force the slide down. Install the two carburetor top screws. Now is a good time to test the throttle action at the grip. Ensure that the slide goes up and down smoothly and fully. It should move very smoothly and return on its own. If not, check cable routing, and for other sources on binding. This can be very dangerous, if not fixed. It could lead to a stuck wide open throttle.
    Install the carburetor to the manifold insuring an airtight seal. Attach the oil injection line (cap off injection spigot for pre-mix running engines). Notice where the fuel line attaches (see picture 11). Finally install the inlet adaptor, and either the airbox or pod air filter. Note, carburetor settings differ greatly when running the stock airbox versus a pod-style (clamp-on) air filter. The 21mm Dell-Orto kit comes pre-jetted for the stock airbox and oil injection. Using a pod filter will require significantly richer jetting. Running pre-mix will also require richer jetting.


    Adjustments:
    Note the positions of the air/ fuel mixture screw and idle speed adjustment on the Dell-Orto 21mm as shown (see picture 12). Also, note the vent line which must simply be vented to the atmosphere (see picture 12). Note on other types of carburetors there maybe more than one vent line. The Mikuni 24mm carburetor idle speed adjuster and idle air/ fuel screw adjusters look very similar.
    To lower your idle speed, rotate the adjuster counter-clockwise (loosen). To raise your idle speed, rotate the adjuster, clockwise (tighten). A couple of small turns is all that is every really needed.
    To richen the idle and low speed mixture, rotate the adjuster counter-clockwise out with 1/4 turn increments. To lean out the mixture, rotate the adjuster clockwise in 1/4 turn at a time.
    Note that the idle mixture screw does NOT affect any RPM greater than just off-idle. It will not cure a lean or rich wide-open or part-throttle running condition. This adjustment is made with mainly with main jets, needle clip position, and to a lesser extent the pilot (slow) jet.



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  9. #9
    apriliaforum newb
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    Just had new big. Bore fitted , now no fuel going through my carb any ideas what could be wrong ( standard carb ) rs 50 am6 2007

  10. #10
    Moderator (ADSUM) Grenadiers's Avatar
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    Assuming your tank is full... Did you turn the petcock back on (if equipped)?

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    Polished Aluminum Varo W/Kick start/Pod Filter/HEL Brake Lines
    HGT Red Brake Levers/LED bulbs/BGM LED Tail Light
    Malossi Delta Clutch w/Blue springs/Red Contra spring & TC/MHR Full Circle Crank
    Malossi 15/40 Primary Gears & Multivar w/5gr Dr. Pulley Sliders/Kevlar Belt
    Michelin Pilot Sport 140/60 Rear tire w/Dyna Beads&TPMS Sensor

  11. #11
    apriliaforum newb
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    It's a vacuum fed one

  12. #12
    Moderator (ADSUM) Grenadiers's Avatar
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    Hum... Not gravity feed? If that's the case, check your vacuum lines for leaks or blockages.

    Tempus Fugit
    06 SR50 (Morini)/AIRSAL 70CC BBK/NGK BR9EIX/Top Speed-117KPH (GPS)!!
    Rear Rack & Top Case/Buzzetti Side stand/Aprilia Racing Shock W/STR8 65mmRiser/HGT Stretch Kit
    HGT PFI Kit/Malossi MHR Team II Pipe/All Polished Water Pump
    Black HGT Gen 3 Fuel Regulator/Stebel Magnum Horn/Glowshift Elite Gauge
    BING 26mm TBA/BGM Pro Reed Block & Pod Filter
    Polished Aluminum Varo W/Kick start/Pod Filter/HEL Brake Lines
    HGT Red Brake Levers/LED bulbs/BGM LED Tail Light
    Malossi Delta Clutch w/Blue springs/Red Contra spring & TC/MHR Full Circle Crank
    Malossi 15/40 Primary Gears & Multivar w/5gr Dr. Pulley Sliders/Kevlar Belt
    Michelin Pilot Sport 140/60 Rear tire w/Dyna Beads&TPMS Sensor

  13. #13
    apriliaforum newb
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    Quote Originally Posted by Grenadiers View Post
    Hum... Not gravity feed? If that's the case, check your vacuum lines for leaks or blockages.

    Will do thanks.

  14. #14
    Moderator (ADSUM) Grenadiers's Avatar
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    Quote Originally Posted by Ted / AF1 Racing View Post
    Removing the gas tank and bodywork
    In a clean and well-lit area of your garage, clear a workspace. Allot of body work has to come off to do a full kit, and you should lay the parts out as they are removed. If possible, lay the bodywork on carpet or some other non-abrasive surface to prevent as much damage as possible to the finish of your plastic. Start by removing the front seat which comes off with the key.
    VERY IMPORTANT
    Turn the fuel tap (fuel petcock) to the OFF position.
    Only proceed with a cold engine and a well-ventilated area
    BTW, If you followed the steps in this first thread, the Petcock may still be set to off...

    Double check for that too.

    Tempus Fugit
    06 SR50 (Morini)/AIRSAL 70CC BBK/NGK BR9EIX/Top Speed-117KPH (GPS)!!
    Rear Rack & Top Case/Buzzetti Side stand/Aprilia Racing Shock W/STR8 65mmRiser/HGT Stretch Kit
    HGT PFI Kit/Malossi MHR Team II Pipe/All Polished Water Pump
    Black HGT Gen 3 Fuel Regulator/Stebel Magnum Horn/Glowshift Elite Gauge
    BING 26mm TBA/BGM Pro Reed Block & Pod Filter
    Polished Aluminum Varo W/Kick start/Pod Filter/HEL Brake Lines
    HGT Red Brake Levers/LED bulbs/BGM LED Tail Light
    Malossi Delta Clutch w/Blue springs/Red Contra spring & TC/MHR Full Circle Crank
    Malossi 15/40 Primary Gears & Multivar w/5gr Dr. Pulley Sliders/Kevlar Belt
    Michelin Pilot Sport 140/60 Rear tire w/Dyna Beads&TPMS Sensor

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