"DYNO" Numbers For SOFTAILS
Intermediate
Joined: Jul 2017
Posts: 30
Likes: 1
From: Denver, Colorado
Here's a copy of my Dyno Sheet from yesterday. My bike is the 2017 Softail Slim S, and only thing I changed is the exhaust (V&H Pro Pipe) and Power Vision Tune. Made pretty good numbers being that it's essentially stock. I'm thinking about going with some S&S 585 cams. Will I need to change anything else going with the 585s?
Stellar HDF Member
Joined: Feb 2014
Posts: 2,710
Likes: 528
From: Lethbridge, Alberta Canada
Here's a copy of my Dyno Sheet from yesterday. My bike is the 2017 Softail Slim S, and only thing I changed is the exhaust (V&H Pro Pipe) and Power Vision Tune. Made pretty good numbers being that it's essentially stock. I'm thinking about going with some S&S 585 cams. Will I need to change anything else going with the 585s?
Jim G
Intermediate
Joined: Jul 2017
Posts: 30
Likes: 1
From: Denver, Colorado
Jim, I looked into the air filter/cleaner before I bought the pipe and everyone said the stock air cleaner was more them enough for the 110" engine because it's a performance cleaner from SE. I guess I need to dig deeper. Thanks for responding.
Stellar HDF Member
Joined: Feb 2014
Posts: 2,710
Likes: 528
From: Lethbridge, Alberta Canada
IF you have a SE air cleaner, there are a couple of possibilities:
- It's simply too small for the engine displacement and freer flowing exhaust (many of the SE air cleaners were designed when HD engines were 96" or smaller)
- SE makes TWO kinds of air filter elements: the kind you oil (like K&N) and the type you DON'T. If you oil the type you are not supposed to oil, you plug it up badly
- The air cleaner is simply dirty (like mine got after my HD mechanic apparently forgot to clean it or replace it at the last major service) and needs replacement (non-oil type) or cleaning (oil type). If you have the oil type and clean it, be careful to oil it only LIGHTLY! The biggest cause of low airflow and even fouled plugs is an over-oiled air filter. It can axctually cause your engine to suck oil from the crankcase ventilation system into your air intake, making things even worse.
Jim G
Intermediate
Joined: Jul 2017
Posts: 30
Likes: 1
From: Denver, Colorado
I will check the air filter for dirtiness. The bike only has 1000 miles on it and I wouldn't think it would be too dirty but I will check. It's the stock non-oil filter.
Yes, making peak power at under 5000 rpm means you have a "cork" in the airflow somewhere.
IF you have a SE air cleaner, there are a couple of possibilities:
- It's simply too small for the engine displacement and freer flowing exhaust (many of the SE air cleaners were designed when HD engines were 96" or smaller)
- SE makes TWO kinds of air filter elements: the kind you oil (like K&N) and the type you DON'T. If you oil the type you are not supposed to oil, you plug it up badly
- The air cleaner is simply dirty (like mine got after my HD mechanic apparently forgot to clean it or replace it at the last major service) and needs replacement (non-oil type) or cleaning (oil type). If you have the oil type and clean it, be careful to oil it only LIGHTLY! The biggest cause of low airflow and even fouled plugs is an over-oiled air filter. It can axctually cause your engine to suck oil from the crankcase ventilation system into your air intake, making things even worse.
Jim G
IF you have a SE air cleaner, there are a couple of possibilities:
- It's simply too small for the engine displacement and freer flowing exhaust (many of the SE air cleaners were designed when HD engines were 96" or smaller)
- SE makes TWO kinds of air filter elements: the kind you oil (like K&N) and the type you DON'T. If you oil the type you are not supposed to oil, you plug it up badly
- The air cleaner is simply dirty (like mine got after my HD mechanic apparently forgot to clean it or replace it at the last major service) and needs replacement (non-oil type) or cleaning (oil type). If you have the oil type and clean it, be careful to oil it only LIGHTLY! The biggest cause of low airflow and even fouled plugs is an over-oiled air filter. It can axctually cause your engine to suck oil from the crankcase ventilation system into your air intake, making things even worse.
Jim G
Stellar HDF Member
Joined: Feb 2014
Posts: 2,710
Likes: 528
From: Lethbridge, Alberta Canada
It would have been betetr to wait with the tune until the air cleaner was replaced because you WILL need a new tune to keep the engine from running lean once you get a good air cleaner on there.
Jim G
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Intermediate
Joined: Jul 2017
Posts: 30
Likes: 1
From: Denver, Colorado
I'm on it! Thanks Jim.
Stock HD air cleaners and exhausts are both deliberate "corks" that, along with ridiculously numerically low gearing, quieten the bikes enough to enable them to pass noise standards. Simply by replacing both the exhaust and the air cleaner with properly selected ones, it is TYPICAL to pick up 14 to 18% more power. No kidding. You have done half the job. Finish it now.
It would have been betetr to wait with the tune until the air cleaner was replaced because you WILL need a new tune to keep the engine from running lean once you get a good air cleaner on there.
Jim G
It would have been betetr to wait with the tune until the air cleaner was replaced because you WILL need a new tune to keep the engine from running lean once you get a good air cleaner on there.
Jim G
Stellar HDF Member
Joined: Feb 2014
Posts: 2,710
Likes: 528
From: Lethbridge, Alberta Canada
Jim G