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Shaking at idle

murgas1

Member
Just got my bike back from the dealer and they say my engine shaking at idle is normal. Nothing wrong!!! The truth is this bike never shook at idle and just recently the shaking has progressively gotten worse. It now shakes the bags , the bars and the rider which it never did before. My guess is O2 sensors and or plugs. Any suggestions?:
 
Completely stock. Ran some high octane fuel through it previously and since then idle has noticeably gotten worse. O2 coated?
 
I always run premium gasoline from any quality station. No discount stuff. It just seems wierd that the shaking has gotten worse and the dealer didn't even think it was wrong. The bike as new was so smooth at idle compared to my 06 FLHX that I thought they sold me a Honda.

The fuel I ran through the bike caused a Ferrari F430 Scuderia to screw up the catalytic converters and catch fire when it was run at the track. I put it in the bike to see if this was the cause of the cat failure on the Ferrari. The plugs and cats were orange in color which usually means there was some sort of a lead additive possibly. That is why I think the O2 might be compromised. Shouldn't use my bike to test these theories I guess.
 
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I think the manual says to run 91 or 93 octane, but not 100, which you can get at some stations. I was going to try a tank, but had read somewhere there's no real benefit on a stock engines.
 
Completely stock. Ran some high octane fuel through it previously and since then idle has noticeably gotten worse. O2 coated?
How many miles do you have on your bike. I think it takes a while on the new closed loop computer systems for the bike to get "regular". It has to adjust to altitude, fuel and your riding style or do what the shop calls "Learning". My 09 CVO took about a week before it adjusted itself and quit popping and stumbling and smoothed out. And yes, it also got a little rougher at idle but it got a lot better off of idle and lost the bog at take off.
 
Street pump gas is nowhere near 100 Octane. 93 is High Test at every station I have been in years.

Before I suspected the O2 sensors, I would say the injectors were dirty.
Lots of things I would check including plugs & ignition 1st.
 
The orange coating is an additive that is added to the fuel. If your plugs have that orange color on them, replace them. You can not get that orange coating off. Usually the orange coating will give you a High RPM engine miss.
I would change the plugs 1st since it is cheap and easy to do.

When I made the mistake of using race fuel like you did, it did not seem to effect the O2 sensors in any way. But it did destroy a near new set of plugs.
 
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