Engine Mechanical Topics Discussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.

High idle after highway speed q

Thread Tools
 
Search this Thread
 
Old Jul 31, 2020 | 04:53 PM
  #1  
highwayman50's Avatar
highwayman50
Thread Starter
|
Stellar HDF Member
5 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Nov 2018
Posts: 2,611
Likes: 1,021
From: Michigan
Default High idle after highway speed q

Hey guys....not sure if this is engine related but, here goes. I have a 2014 SGS with a Arlen Ness big sucker air intake, D&D Fatcat exhaust, Andrews 48H cam and a TechnoReasearch tuner. I had all this installed winter before last and all has been great. The last 3 days on my way home from work...first leg about 20 miles of interstate. When I get off the interstate (about 75mph) with and without the cruise and stop at the end of the ramp the idle will not drop below 16grand unles I let the clutch out a bit like I'm going to take off. Second leg is about 4 mile of 50-55 mph and it does the same thing. The rest of the way is about 15 miles of of 45-55mph with a few lights to stop at...it runs and idles perfect. If I do a ride without any interstate...no issues. If I do a ride with just a couple 3 miles of interstate, no issues. Seems to happen with prolonged interstate travel. Bike haunted?
 
Reply
Old Jul 31, 2020 | 05:13 PM
  #2  
46knuck's Avatar
46knuck
Tourer
15 Year Member
Photogenic
Photoriffic
Liked
Joined: Nov 2007
Posts: 452
Likes: 93
From: Center of Kalifornia
Default

I am sure that the electronics on this bike are involved in some manner. Nothing happens without a sensor giving some type of signal to some module that then sends another signal to a relay. Likely need to hook her up to a tester of some kind at dealer or ?
 
Reply
Old Aug 2, 2020 | 08:54 AM
  #3  
Bloody Marvelous's Avatar
Bloody Marvelous
Road Captain
Joined: Jun 2018
Posts: 597
Likes: 285
From: Gouda
Default

High idle usually indicates additional air coming into the engine, possibly a leak between the throttle body and the manifold. Seems odd that it only occurs after interstate riding though. Could also be a throttle issue. I'm assuming it's got an electronic throttle, maybe it's injecting more fuel because the engine's running too hot.
 
Reply
Old Aug 2, 2020 | 09:39 AM
  #4  
highwayman50's Avatar
highwayman50
Thread Starter
|
Stellar HDF Member
5 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Nov 2018
Posts: 2,611
Likes: 1,021
From: Michigan
Default

Originally Posted by Bloody Marvelous
High idle usually indicates additional air coming into the engine, possibly a leak between the throttle body and the manifold. Seems odd that it only occurs after interstate riding though. Could also be a throttle issue. I'm assuming it's got an electronic throttle, maybe it's injecting more fuel because the engine's running too hot.
Thanks. Its been raining since I last parked it, been wanting to take it out one more time to see if issue persists. Not sure about it running to hot, seems like it would run hotter in the stop and go traffic, no? I'll probably have to take it to the dealer and let them hook it up 😕
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KarmaSportster
Ignition/Tuner/ECM/Fuel Injection
12
Jul 11, 2023 08:32 AM
Jed Clampett
Milwaukee Eight (M8)
4
May 4, 2020 01:02 AM
DeafDude
Touring Models
5
Apr 13, 2012 03:56 PM
SCUD
Sportster Models
14
Aug 14, 2009 02:13 PM
Spider51
Touring Models
9
Sep 13, 2007 02:41 PM




All times are GMT -5. The time now is 03:13 PM.

story-0
7 Times Harley-Davidson Chucked Tradition Out the Window

Slideshow: Harley-Davidson built its reputation on nostalgia, but every so often, the company took a hard left turn into the future.

By Verdad Gallardo | 2026-05-20 11:18:19


VIEW MORE
story-1
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-2
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-3
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-4
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-5
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-6
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-7
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-8
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-9
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE