Originally Posted by Kags
Apearenty the HSR 42 is too lean for my build out of the box. I was almost sure these carbs tend to be on the rich side for most 95"? I need to get the motor broke in for the main but would you change the main or the needle to make it through the brake in? To recap my build KB-10.5:1, S&S 585 cams, 2>1 exhaust, S/E race igition.
Its running hot and the plugs are now lean. I doubble check & no air leaks.
As mentioned, Mikuni has a very good tuning booklet. If you did not get one with the carb, you can download from there site.
If you are not using a one range cooler plug, I would go that route before you start to re-jet.
You can get one range cooler champion and autolite plugs at most auto parts dealers. I get mine from advance auto.
Champion - RA6HC
Autolite - 4163
If the bike is detonating try plugs first. If this does not help then your timing & advance slope will need to be adjusted. No reason to waste gas to cover up the possible real problem.
My 95TC had a compression ratio of 11:1. Carb jetting (mikuni45) was 97 needle, 165 main, 25 pilot, 60 exc pump.
Even with the cooler range plugs, I had to have a custom ign map made to control detonation. I used a Zippers ign module (DTT private label) so Zippers made me a custom map for free. Solved the detonation problem. Not sure if they do that anymore.