Mikuni HSR42 jetting
#1
Mikuni HSR42 jetting
I am just installing 95 inch with KB 9.8:1, Dewy's heads, Andrews TW38G, ProPipe and HSR42. I live at 700 feet elevation. Does anyone have any good suggestions for beginning jetting with stock ignition? HSR is currently jetted stock. I have been planning on going to a 165 main, moving needle 1 clip richer and dropping pilot to 22.5 unless anyone has any experience or suggestions. 2005 FLHRS
Thanks for the help.
George
Thanks for the help.
George
#2
I am just installing 95 inch with KB 9.8:1, Dewy's heads, Andrews TW38G, ProPipe and HSR42. I live at 700 feet elevation. Does anyone have any good suggestions for beginning jetting with stock ignition? HSR is currently jetted stock. I have been planning on going to a 165 main, moving needle 1 clip richer and dropping pilot to 22.5 unless anyone has any experience or suggestions. 2005 FLHRS
Thanks for the help.
George
Thanks for the help.
George
#3
Thanks,
I have been running the carb for a couple of weeks with the cams, propipe, and big sucker. Not as "crisp" as I would like but too lazy to spend time jetting when I am going to change bore, compression and head flow in just a week or two. Jetting not enough to cause issues but not "crisp". Just wondering if someone had a similar build to get closer from start. Have read of several folks who go to a 22.5 pilot and 165 main right off the bat with the 50 nozzle. When I finish build I will really get serious about the dialing. I have memorized the Mikuni tuning manual.
George
I have been running the carb for a couple of weeks with the cams, propipe, and big sucker. Not as "crisp" as I would like but too lazy to spend time jetting when I am going to change bore, compression and head flow in just a week or two. Jetting not enough to cause issues but not "crisp". Just wondering if someone had a similar build to get closer from start. Have read of several folks who go to a 22.5 pilot and 165 main right off the bat with the 50 nozzle. When I finish build I will really get serious about the dialing. I have memorized the Mikuni tuning manual.
George
#4
Get the bike warmed up and turn the air/fuel screw in untilt he bike starts to stumble then back it out until the idle returns then use the idle adjustment to help with the crispness. Lack of crispness can be due to having the idle too low and/or having the wrong cam or pipes in the bike. I would NOT change any jets until I did the motor work is done. In short, do the work then fine tune the carb.
Maybe consider doing the work then taking to a good dyno guy and having him fine tune it for you...
We did a 45mm Mikuni on a 107 evo S&S with a .600 cam yesterday and got the bike warm and had it running well in 20 minutes but are still gonna put it on the dyno next week as we are changing the cams to .631's. Once the work is done we will turn it over to a good dyno guy and have him get it perfect...
Maybe consider doing the work then taking to a good dyno guy and having him fine tune it for you...
We did a 45mm Mikuni on a 107 evo S&S with a .600 cam yesterday and got the bike warm and had it running well in 20 minutes but are still gonna put it on the dyno next week as we are changing the cams to .631's. Once the work is done we will turn it over to a good dyno guy and have him get it perfect...
Last edited by cowboy1; 06-11-2009 at 03:08 PM.
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