HarleyTechTalk

Technical Forums => EVO 1340 => Topic started by: Deye76 on June 18, 2020, 06:45:15 PM

Title: Observations Ultima 113"
Post by: Deye76 on June 18, 2020, 06:45:15 PM
Some long winded observations on Ultima, only the 113". Ever since I got the motor, it was extremely hard to get it to idle good, get decent gas mileage, and if it was correct AFR in the Interm. jet then it went lean up top, and vice versa for the main jet. Whenever riding I could always smell fuel no matter how it was jetted or adjusted, even after a dyno tune. Yeah I know people don't like S&S carbs, and I'm not a tuner by any stretch, but have run them for years. I was told the R1 was the problem, so got a brand new S&S G, a little better, but not much. So after the 113" motor ate a lifter and took out the cam, I replaced the Ultima cam with a S&S .600 as I had experience with it in a 100" Evo years ago. What a difference 5 deg of Intake close, and overlap makes. Immediately I got the motor to idle smooth, low end torque waaay better, and fuel mileage jumped 10mpg to the good. That Ultima cam is probably good in the Ultima 120" motors, but I think it's too much for the 113's.
Title: Re: Observations Ultima 113"
Post by: turboprop on June 18, 2020, 06:51:11 PM
Sounds like you are getting that engine sorted out.
Title: Re: Observations Ultima 113"
Post by: ecir50 on June 18, 2020, 07:18:25 PM
now she is ready for some head work.
Title: Re: Observations Ultima 113"
Post by: JW113 on June 18, 2020, 08:52:55 PM
Excessive intake timing means intake regurgitation, meaning it's pushing air out the carb, then pulling it back in, essentially "double carburating" the intake charge. At least until the RPMs get way up. Have had the same issue, and why you smell gas, it's coming out the air cleaner...

-JW
Title: Re: Observations Ultima 113"
Post by: capn on June 19, 2020, 02:44:42 AM
I agree with Deye.That 264 ultima cam does not run well at lower rpms.Even in the 120.Happen to have a 600 S&S on hand but I never tried it.Maybe I will.
Title: Re: Observations Ultima 113"
Post by: Deye76 on June 19, 2020, 05:39:19 AM
"you smell gas, it's coming out the air cleaner..."

I know that, with the .600's smaller overlap, it reduces the unburned fuel and leads to more complete combustion of the fuel. That 264 Ultima cam sounds nasty, like a hot rod, but a street bike doesn't spend the majority of it's time at 4 grand, unless you run around in 2nd gear all day long. LOL
I'd wager the S&S .585 evo cam would work good too, especially in a heavier bike. I had my FXR weighed yesterday at a state certified scale, 672 pounds, bags, P fairing and a full tank of gas.   
Title: Re: Observations Ultima 113"
Post by: hbkeith on June 21, 2020, 07:02:53 AM
my 113 in my FXR has a stock Ultima cam and a Mikuni , it dosent like going slow either , but man be carefull twisting the throttle in first gear  :bike: , i like to wait till im in second then clutch it and smoke the tire past my buddies