I highly recommend rejetting once the RAIS Power Tube is installed. A complete set of instructions will be included with your purchase, which includes jetting recommendations.
As far as your initial attempt at rejetting, you’ll need a 3 and a 4 mm allen wrench, a 10mm wrench, needle nose pliers, a flat screwdriver, a 3/32 drill bit and drill, a 3/32 sheet metal screw and a small set of vice grips to grab on to the float bowl screws as they are typically very tight from the factory and very easy to strip. I’ll include 4 allen screws that you can use to replace the phillips screws that use the 3mm allen wrench.
Loosen the carb boots on each side of the carb and the boot attached to the air filter canister. Detach the rubber vacuum hose at the top of the carb and pivot aside. Pull the crankcase vent hose out of the slotted retainer. Lift the carb and canister boot out by pivoting at carb throat and canister boot and pivoting/lifting up. Once loose, stuff a rag in the intake and filter canister to keep debris out. Remove the 2 wires from the carb heater. Lay the carb over on its side toward the passenger side. All the fuel in the bowl will drain out unil empty. You do not have to loosen or remove the enricher cable or throttle cable. Remove the carb heater which is the fitting that the two wires attahced to. Try to loosen the phillips screws on the float bowl but be very careful as they will strip. If they don’t break loose relatively easily, use the small vice grips to assist the screwdriver in getting them loose by gripping the outside surface of the screw. Once all 4 screws are removed, remove the bowl carefully. The main jet is the jet in the middle surrounded by the brass sleeve and kind of recessed into same. Change your jet and put in back together in same order as removal.
Initially, you’ll need to remove the brass plug hiding the a/f mixture screw. Its probably 1 turn out from the factory. It needs to be out 1.5 to 2 turns. Its the brass plug closest to the front of the carb. Drill it with about a 3/32 bit just barely through the top because you don’t want to damage the screw. Take a sheet metal screw and screw it in the hole and work the plug out which will expose the a/f screw. Screw the a/f screw softly until it seats and then out 2 turns.
You will also want to enhance your mid range performance as well. You’ll need some needle nose pliers to pull the needle retaining plunger out. Remove the CV carb top by removing the 2 phillips screws on top of the carb. The slide is under spring pressure so remove slowly. Pull the slide and diaphragm out. Pull spring out and look inside. You can see the plunger holding the jet needle in place. It is also under spring pressure, albiet a small amount. It takes a pretty good tug the first time. Be sure not to lose the spring under neath. If you retain the stock jet needle, I would swap the tick and thin washers on either side of the jet needle circlip and put it back together. If you go with the Dynojet needle, I would start on the second groove from the top. Install dynojet jet needle and use their slide spring (different than the spring mentioned above). Before careful to properly place the slide and diaphragm back in place correctly and in proper position. The dynojet kit is going to afford a different mid range performance curve due to the taper of the jet needle and lighter would slide spring. It is a good kit in my opinion and experience.
Based on your situation, you will likely want to get a 147.5, 150, 152.5 and 155 mikuni mains if you choose to simply rejet. My guess is that you would end up running the 152.5 but you will want to have the option to go up or down if necessary. I would also pick up a 42.5 and a 45 pilot jet. If you go with a kit, such as a dynojet kit, simply follow the kit instructions and try it out. You’ll likely end up running the dynojet 160 main given your elevation. I’m running a 165 at 600′ with several other modifications. The main jet numbers on mikuni jets and dynojet mains are not equal. A 165 dynojet main is roughly equal to a 155 mikuni main.
After all back together, crank it up and adjust idle speed if necessary. Let it warm up and take it out and assess the way that it transistions off idle and into mid range followed by top end. Jetting is the sum of all components, so you want to get your idle right first, then transition off idle, best mid range acceleration and finally best top end.
Once all of this is done initially, it takes about 15-20 minutes to do it again if needed or to correct any specific circuit problem recognized.
With the RAIS Power Tube and air filter, you’ll noitice a healthier responding motor across the powerband with absolutely no running problems once properly jetted. There is an increased amount of intake noise but that makes sense given the change in size of the opening. You can realize the same benefit by removing the o.e.m intake and running ‘04 style but you will be drawing air from under the engine cowling which may be quite dirty. One of my original goals with the RAIS was to retain the ‘05/’06/’07 intake design. The dynojet kit will primarily provide enhancement to mid range performance as you can achieve same top end performance with mikuni mains alone.
Please feel free to give me a call if you have any questions as I want to be certain that you are totally satisfied with the Roostin’ Rhino RAIS Power Tube.
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Rhino
