Rough Idle

[sco907]

I am a new member. I purchased my 2005 FJR last year from its second owner. It has 30,xxx miles. I have noticed to my annoyance that it does not idle very smoothly though, with the effect getting worse with the engine getting hotter.

I had a throttle body sync done a little over 1,000 miles ago with new spark plugs (NKG Iridium CR8EIX) and cleaned the air filter at same time (and all the recalls have been done, checked with Yamaha).

I made a quick video of it and I would appreciate if some of the more knowledgeable member of the forum could take a look and tell me if I am being paranoid or what my next best action would be. I started from a cold start, the bike warms up at around 2:18, I also put the camera down on the right side at the end of video where you can more clearly hear what I call the more tractor like element to engines sound (not sure if that is typical):



I have been looking at the forum and found this thread (https://www.fjrforum.com/forum//index.php?showtopic=22734&st=0&p=268059entry268059) on corrosion and thought it could be a possible cause. The other possible cause I am worried about is the CCT.

I am not very mechanically inclined or knowledgeable but I am slowly learning. Any advice would be appreciated.

 

[kamal]

I'm sure you will get a ton of feedback on this and figure it out.

My '04 was doing a similar thing + it was jerky at low throttle openings (around town), but fine on the highway. In my case, a throttle body sync and new plugs fixed it completely.

Was your bike doing this before you had the TBC done?

Al

 

[03HiYoSilver]

Do Check your Main Harness Connector and see if it needs Cleaned.

Also, you may want to do a SeaFoam Treatment of about 1 OZ per gallon with a Tank and see what happens.

https://www.seafoamsales.com/gasoline-engine-faqs.html

 

[sco907]

Do Check your Main Harness Connector and see if it needs Cleaned.

Also, you may want to do a SeaFoam Treatment of about 1 OZ per gallon with a Tank and see what happens.

https://www.seafoamsales.com/gasoline-engine-faqs.html

I didn't use seafoam but I did run fuel injector cleaner through it (can't remember brand).

 

[03HiYoSilver]

Make sure your idle is set (when warm) at 1100-1200 RPM... this helps alot and keeps the Slack off the Chain too.

 

[sco907]

I'm sure you will get a ton of feedback on this and figure it out.

My '04 was doing a similar thing + it was jerky at low throttle openings (around town), but fine on the highway. In my case, a throttle body sync and new plugs fixed it completely.

Was your bike doing this before you had the TBC done?

Al

Thanks, it runs well for the most part, esp. on the highway. Its definitely a little jerky around town, but coming off an R6 its still pretty smooth.

Embarrassingly I am not certain when it started, though I think after I got the bike. I have moved three times since I got it so its been a while since I had time to mess with it, or even ride it a lot to be reminded. There were more vibes than I liked at high rpms before the TBC, got a bunch better and is still smooth. I was reminded because we have had a number of very hot days here in Maryland and it seems to get worse, does not sound pretty at stoplights.

 

[sco907]

Make sure your idle is set (when warm) at 1100-1200 RPM... this helps alot and keeps the Slack off the Chain too.

Yeah I was messing with the idle the other day to see if it was bouncing off a lower limit. I set it high, 1,500-1,400 and it still did it. I think me messing with it is why it started out low in the video and I had to adjust it.

Edit: if no one else recommends anything else by this weekend I will take a look at the harness connector and see if cleaning it makes a difference. Thanks for the advice, and sorry for the back and forth, forgot to include some details.

 

[kamal]

Let us know what you find.

My connector was 'like new', but this area is semi-desert - the air is pretty dry.

As I understand it, the TBS shouldn't affect high rpm vibes.

Good luck.

Al

 

[RossKean]

Does the noise or roughness seem to come from the right side of the engine? If so, you may have an issue with your cam chain tensioner. Although total failure is fairly rare, there have been a number of catistrophic failures documented on this forum. The results are not pretty. Parts are not terribly expensive although replacement is a bit of a pain. Check it out ASAP.

Ross

 

[Bounce]

Rough idle is, most often, the running-temp idle set below 1100 or a case of seriously needing a throttle body synch. Those also just happen to be a couple of the easiest things to DIY on the bike (other than change the oil/filter, check the tire pressure, and fill the gas tank).

The details on the throttle body synch are here for the searching.

 

[rbentnail]

One tooth off on the crank sprocket gives exactly the same symptoms.

 

[sco907]

One tooth off on the crank sprocket gives exactly the same symptoms.

I am feeling more and more that this is what it will end up being. I will look at the harness but if that does not fix it the cam is next. Is there a good instructional with lots of pics? All I could find was this: https://www.fjrforum.com/forum/index.php?showtopic=130394&hl (and a bunch of threads with brief descriptions of successful fixes). Can I have a regular MC shop do this, or do I have to find a Yamaha shop? Reading other users testimonials without clear instructions are making me nervous, I definitely do not want to mess up my engine as others have. And I have only have rudimentary understanding of how the cam works and what it does.

 

[RossKean]

One tooth off on the crank sprocket gives exactly the same symptoms.

I am feeling more and more that this is what it will end up being. I will look at the harness but if that does not fix it the cam is next. Is there a good instructional with lots of pics? All I could find was this: https://www.fjrforum....topic=130394 (and a bunch of threads with brief descriptions of successful fixes). Can I have a regular MC shop do this, or do I have to find a Yamaha shop? Reading other users testimonials without clear instructions are making me nervous, I definitely do not want to mess up my engine as others have. And I have only have rudimentary understanding of how the cam works and what it does.

Does the problem date from the last valve check? If so, a skipped tooth might be the culprit. If it was good after a valve check (or if a valve check hasn't been done), the only way you could have a skipped tooth is if the CCT is BAD - be very, very careful running it under these circumstances.

 

[sco907]

One tooth off on the crank sprocket gives exactly the same symptoms.

I am feeling more and more that this is what it will end up being. I will look at the harness but if that does not fix it the cam is next. Is there a good instructional with lots of pics? All I could find was this: https://www.fjrforum....topic=130394 (and a bunch of threads with brief descriptions of successful fixes). Can I have a regular MC shop do this, or do I have to find a Yamaha shop? Reading other users testimonials without clear instructions are making me nervous, I definitely do not want to mess up my engine as others have. And I have only have rudimentary understanding of how the cam works and what it does.

Does the problem date from the last valve check? If so, a skipped tooth might be the culprit. If it was good after a valve check (or if a valve check hasn't been done), the only way you could have a skipped tooth is if the CCT is BAD - be very, very careful running it under these circumstances.

The last valve check was performed before I bought the bike so I am unsure. I just went out and listened to the bike some more and the Cam chain area seems to be quite loud and rattly sounding. Anyone have the new part number for the improved tensioner? Thanks everyone for your help!

 

[sco907]

Thanks all for your help. I have managed to reduce the issue significantly by cleaning the wiring harness connectors, there was a very minor amount of corrosion, and running several tanks of fule with seafoam through it. The issue still exists to a lesser extent but given that these methods worked I doubt anything bigger is going on. I also talked to a local mechanic, and he basically told me that he doesn't think it would be worth me paying him to investigate given the number of miles on the bike.

Once again thanks all.

 

[Bounce]

"number of miles"?

30k isn't even a quarter of what it has in it. What's this mechanic used to working on? Harleys and dirt bikes?

 

[sco907]

"number of miles"?

30k isn't even a quarter of what it has in it. What's this mechanic used to working on? Harleys and dirt bikes?

Yeah seemed a little pessimistic to me as well (most of the shops seem to focus on harely/cruisers around here). I came to provide an update in case anyone else runs into this issue and comes across this. I got a valve sync done and it seems to have further improved things. I have not gotten to test it much as the riding season is pretty much over, so we shall see next time I get it in some truly hot and humid weather (when the symptoms were the worst).

A note, the shop I went to broke my top panel plastic on the right hand side back piece. It had a hairline crack but they cracked a section out of it and put some of the other plastics together wrong. If anyone has a spare of that piece that is in good condition that they would be willing to sell cheap PM me.

Also the shop discovered that some bolt for the cam chain tension-er housing has a built in crush washer that needs to be replaced. This was found out by me when my bike started spraying out oil out its right side just past the panel. Not a pleasant surprise.