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Hey guys I need some guidance on what jetting to put in my Mikuni HSR 45 for my 96" stroker shovelhead. I had an Ultima R1 (S&S G copy) on it when I built it and I was having a hard time getting the bike to run right. One day it would run ok and then the next it would be so far out of tune it would take 1/2 a day to get it so I could ride it and even then it never ran right. After checking everything out it came down to being the knockoff carb giving me all of the trouble. So last week I ordered a new Mikuni HSR 45 for it. Now the tuning begins again. It already runs way better, but needs to be dialed in. The jets in the carb now are a 25 pilot jet, 160 main jet, 97 needle on #3 groove, and a #70 accelerator pump nozzle. These are the factory jets. Now a little bit about the engine: 96" shovelhead, S&S heads, 10.25:1 compression, Comp V-thunder 4050 cam, solid lifters, magneto ignition, kickstart only. Starts and runs fairly decent with the new carb, it is getting too much fuel, so from the guys on the shovelhead forum they told me to get a #50 accelerator pump nozzle. Which I am still waiting on. I also ordered a few different pilot jets: 20, 22.5, & 27.5. I was told the main jet should be fine. Does anyone have a similar combo or can recommend some jetting combinations to help get me close to perfect so I can ride the bike? The only dyno I have access to is the butt dyno. Any help is appreciated. Here are some pics of my chop and engine that I built and completed last November:
