Hightower, what are you currently running for a jet/needle/pilot?

Just wanted to see how close we were.

I will be starting a new thread. Called TM45 going to the Dyno. I have my stock numbers, partial stage one and now I'll have them with the addition of the TM 45. I'll know what the final result will be this Saturday. I'll share the numbers as soon as I get them. Obviously, the actual numbers are not important rather the increase and/or differential is what is important.

 

I'm 800' elevation
45 pilot, 2.5 turns out on screw
#95 needle, 5th groove
155 main
carb mount K&N

When I go to sea level (silver lake dunes, MI) I install 157.5

 

Hrm. so you guys are saying the HSR42 would be the best choice if I don't plan to mod any more than it is right now?

I have no intentions of putting any more money in the engine...only like tires and stuff.

Also the HSR42 would give better mileage I suppose...Same as stock or close to that of the 45??

Anyway...not sure if I want to take out the carb and send it out to the states...Don't really know if it's worth the effort for what it will give ?? (and the down-time).

bleh..I have to work in an hour, so I'll check my carb settings and elevation stuff tomorrow and let you guys know.

 

I don't necessarily agree with Hightower on the activation and or use of the Accelorator Pump (A/P) on the HSR-45. When I first set-up my 03 Baja up with the RWR Stage 1 Kit I was frustrated with the OFF-IDLE performance first 1/4 turn of throttle. I went through the gammit on jetting. Too lean, reduced of the hesitation and the top-end suffered. Too rich- even more bottom end hesitation, Blubbery Top-End. In short I have been able to install and tune the carb for use with the AC Pump. It is a rather simple process.

Replace the stock "60" A/P Jet with a "50" remember to point the spray (Nozzle) opening at the needle. Reinstall the spring and plunger in the bowl, Insert the Rod from the bottom of the open carb remember slide the rubber boot onto the Rod from the top as it inserted. Next inspect your work and reinstall the bowl assembly. ( don't forget to install the drain plug)

Start by Turning the A/P screw out so that it A/P lever begins to push the Rod down this activates the pump. It is best to start the next process with the Carb lightly mounted in a vise or other fixed position (so that not to block the openings). Attach a fuel source to the fuel inlet. Active the throttle a few time until fuel is sprayed from the nozzle throught he middle of the carb. (Do not suggest looking down the barrel of the carb while doing this). Next, once you have a good spray (and yes it will probably spay 20+ feet) it's time to set the pump. Screw the small A/P stop screw in until it is flush with the top of the carb. Then contininue to loosen the A/P set screw (the one with the spring) a half a turn at a time and activate the throttle, this will begin to depress the pump rod. Repeat this process untill you can obtain a spray pattern of about 18 to 20 inches out of the carb.

It will probably take some time to dial this in. You will have to make the adjustments (Between the Set screw and Stop screw) several time to to get this right. While performing the adjustments pay close attention to the A/P lever. You will want to see that when you barely roll the throttle the pump rod will activate and very quickly stop. "It only takes a very short Squirt"

You can download an HSR 45 Tuning Manual at the following site Good INFO!

HSR Tuning Manual
http://www.mikunioz.com/download.htm...uning%20manual

 

There is also a hard-copy of the tuning manual available directly from Mikuni. Covers the 42/45/48. Call 818-885-1242. Beware, the people on that side of the company don't like to talk about OEM carbs....they seem offended.