03 FJR rough idle

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deepsouthfox

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Purchased an 03 about a month ago. The idle was rough when I got it, but the deal was sweet. It accelerates fine, almost need a G-suit. and cruises great also.

But the Idle and Whine bug me. I think from what I read on this forum, the Whine is normal. I have used techron in 2 tanks with no results. I will try the throttle body sync first then a TPS change. Any advice from long time FJR owners is welcome.

Long time Harley Rider:

I made the switch:

I'm glad I did.

FJR's Rock.

 
TPS isn't the problem if it's just rough idle.

Mine idles rather poorly, and I had a plug that would foul within a few days after replacement. I've gotten where I "rotate" my plugs; once in a while swap #4 with another cylinder's plug, so the fouled plug gets cleaned in another cylinder, and #4 gets a clean plug every so often. I think I have an injector that runs richer than it's supposed to. I also replaced one of my coils when I found some kind of residue on the plug wire coming out of it, which helped.

Like yours, idle is not exactly silky, seems to miss once in a while, but under power it is smooth and strong, so I haven't really been worried about it.

I also know that I'm overdue for a valve check.

Straight-cut gears will whine. All the gears in the transmission are straight-cut, as are the gears driving the balancers on each side of the crankshaft.

 
Thanks for the feed back. I have already changed the plugs as i had No 3 foul. I think it was my fault because I dumped a lot of marvel mystery oil in the tank to see if it would clean up the idle. I was wrong. Have you balanced the fuel injectors. Thats my next step. I will have it in the shop next week for a fork seal change, but I doubt they will give me any free information.

Have a good weekend.

 
I've done a throttle body sync, if that's what you mean by balancing the injectors. I hit that a couple times a year.

 
I've done a throttle body sync, if that's what you mean by balancing the injectors. I hit that a couple times a year.
Sort of piggy-backing here as I can't say that I'm totally happy with the low rpm operation on my '05. Very touchy throttle where very small movements will yield large, instantaneous jumps in rpm and that range from idle (1100 +/-) through 3000 rpm is pretty rough and poppy but it smooths as rpm increases.

What type of sync gauge are you working with wfooshee? I have an Emglo gauge which is using 4 round vacuum dials, not the tubular type like the Morgan or motion Pro. My needles are extremely jumpy and very hard to pin down a good reading, it's more like a strobe effect and it seems as the tubular liquid type gauge is more stable and easily readable.

 
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Motion Pro, and it was useless before I put the little restrictors in the vacuum hoses. I knew they belonged there, but I wanted to see what they were talking about in the directions, and sure enough, the reading fluctuates too much and too quickly to be usable.

The restrictors have a tiny orifice, less than a pinhole, even, which allows pressure to equalize but restricts pulsing of the readout. Maybe you're supposed to have something like that in your setup.

 
Affirmitive, the restrictors are there but no instruction included for their use. You just confirmed my theory, thank you.

 
Affirmitive, the restrictors are there but no instruction included for their use. You just confirmed my theory, thank you.
Make sure cold start on throttle bodies are free moving. Bike will run fine on open throttle but tick over is very lumpy. You may need to remove the throttle bodies to check though.

 
I had the rough idle issue as well.

TPS was replaced under recall,

still no fix.

Last Spring I bought a brand new GEL battery, and the problem seemed to disappear for a few weeks.

Then it came back.

@!#$^&&**(*(()())

A search here on the FJR forum found this thread:

https://www.fjrforum.com/forum//index.php?s...mp;#entry268059

Last month I finally pulled off the tank and cleaned the connectors, and

VOILA,

no more rough idle.

Thanks for the tip ....

two Yamaha shops couldn't fix it, but the FJR forum gave me the info i needed to fix it myself.

[;{)

LAZ 1

LAZ 1

 
LAZ,

Glad this procedure was able to fix your problem... it is amazing just how many intermittent conditions are solved by this.

 
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