Bike won't start due to carbon build-up

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jam'n

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Prospect, KY
I have a '07 FJR with 15,889 miles. I ride the bike year round when possible and met all service requirements. I drive it at least 1-2 per month during the winter months (2-3 times a week during the other months) and the longest I have had fuel in a tank is 2 months. The other day, I pull it out the garage and it wouldn't start.... Starter works but won't fire. I drag it down to the dealership where, after 2 weeks a breakdown, they tell me that the reason is I have excessive carbon build up on my valves. They also told me that they doubt that Yamaha will cover this under the extended warrantee since this is caused by bad gas. I explained my situation and asked them what else I should have done to prevent this. They mentioned adding stabilizer but other than that they couldn't think of anything else. I said; "when? Between each fueling?" They just shrugged their shoulders. Are there any recommendations out there regarding this issue of carbon build up after 3 years and 16,000 miles. How about the issue with the extended warrantee or am I just out $1,000 plus?

 
Sounds like you need to ride it much more, if you can get it started do a few IronButt rides, that will clear her right up.

 
I think that if you can get a second opinion, you should!

That sounds like a tall tale!

Did they show you the buildup? it would really have to be pretty bad to stop the engine form starting.

It just sounds wrong!

 
Wont's start due to carbon build up? Sounds like BS to me.

Yeah, and the starter doesn't work well becuase you don't use it very often. :angry2:

God help me.

Find a new dealer.

 
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jam,

This is HARD to Believe. Do you ride your bike easy all the time.... or always keep it below 5k RPM?

Here are my old valves @ 37k miles: https://www.fjrforum.com/forum//index.php?showtopic=23034&st=0&p=271113entry271113

Do you see any Carbon Buildup?

If anything, more possibly Clogged Injectors, Tank, and/or Lines. Have you seen your Open Head & Valves?

Something does not seem correct with this diagnosis and someone out there is trolling for fish.

 
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While possible, it is extremely unlikely that this is the problem with the bike. I'd get my bike the heck out of there right now. If not, you're most likely going to spend a lot of money and still end up with a bike that doesn't run.

Joe

 
...They mentioned adding stabilizer but other than that they couldn't think of anything else. I said; "when? Between each fueling?" They just shrugged their shoulders. Are there any recommendations out there regarding this issue of carbon build up after 3 years and 16,000 miles...
Yamaha Ring Free™ is an excellent de-carbonizer. A compression test or a leak-down test will confirm or condemn the dealers diagnosis. I also feel that a 16k mile bike, no matter how it is ridden, should not be carbon bound.

since this is caused by bad gas
That is a scary statement. Where were you purchasing this alleged rouge gas? Did you dealer taste or test your gas to determine it is bad? Exactly how was the gas bad?
 
I felt the same way. I did go down there and look and although I am no expert, it did look like quite a bit of carbon build up. I have some photos but I am not sure how to upload them to post by hiting a URL. The mechanic did shine a light though the exhaust port and I did see light through the valve seats. The valve that he did show me had spots of carbon that he said was causing the valves not to seat correctly. The repair is to just clean everything up and build up. He did perform a leak down test and the problem was through the exhaust. Other than that, I don't know what else he checked. I just never heard of bike not to start because of carbon. At least a bike only 4 years old with 16K. I do ride easy since most of my riding is commuting. However there are times that I do open it up out on the back roads (1-2 times a week during the summer). In fact the last time I road it, I tried to blow it out since it was the end of winter and I just wanted it to breath in the fresh spring air. I called a couple of other dealers and they are having a hard time imagining a bike with 16K getting to that point. I just don't know what I could had done differently. I appreciate everyones input.

jam,

This is HARD to Believe. Do you ride your bike easy all the time.... or always keep it below 5k RPM?

Here are my old valves @ 37k miles: https://www.fjrforum.com/forum//index.php?showtopic=23034&st=0&p=271113entry271113

Do you see any Carbon Buildup?

If anything, more possibly Clogged Injectors, Tank, and/or Lines. Have you seen your Open Head & Valves?

Something does not seem correct with this diagnosis and someone out there is trolling for fish.
 
+1 on the BS. Carbon build-up will not prevent the engine from starting. Gunk in the fuel system will, but it won't be carbon; it will be gum and varnish from old, un-stabilized gas, or some really bad gas. (Or diesel fuel) Today's ethanol-added gasoline starts to go bad in a month. Either use it up sooner, or add gas stabilizer (Sta-Bil Marine formula is my choice)

But the first thing you need, in my opinion, is another dealer. Good luck!

pete

 
"I do ride easy since most of my riding is commuting." (probably a short commute?)

Jam,

Sorry you had to go through this rare process.

A few things to help you to keep this from happening again:

1- Get your bike warmed up to proper operating temps.

2- Keep your bike's rpms above 4k RPM - if your commute is short, above 5k RPM (this will keep your engine hot enough early to burn off any excess carbons.

3- Use "Top Tier" Gas.

4- As Ionbeam said above, periodically use RingFree or SeaFoam gas treatment as preventative maintenance.

If you do #1-#3 above, #4 won't be so critical except for usage during the Storage Months.

Hope this helps....

 
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Entirely possible.

<Clicky>

"Bad news my way today. ~23k 2006A, tech at Powerhouse reports back cylinders 3 & 4 at 60 & 80 psi respectively. Cylinders 1 &2 at 180, 190. Leaking past intake valves. Covered by warranty but still.. mad.gif No wonder it was running rough at Death Valley.

I noticed about 4 months or so ago that my mpg went from 40's to low 30's. "

 
Something isn't right here. If a carbon buildup is indeed the issue, it didn't just jump on the valve seat or on the valve stem after you shut the bike off the last time you rode it. If a valve was not seating the bikes performance should have suffered. This should have been apparent on your last ride. Leakage on one jug shouldn't keep the bike from starting, it would just keep it from running at 100% power. I've torn down many engines with bad valves and exhaust noise during a leak down. I've never seen *carbon* hold a valve open. At 3600 rpm that's 60 crank revolutions per second and 30 open/close cycles per valve per second with ~100 pounds of spring tension. I've always figured that the jack hammer effect would keep the seat reasonably clean. Any leakage I've seen was caused by damage, usually to the valve with some damage to the seat, not by a foreign body holding the valve open. Valves and valves seats are tuff stuff, but they are not indestructible, defects occur. Sometimes damage occurs for no good reason. Though you truly may have leakage issues I think your wrench is either dumbing down his techno speak in an effort to make you see his perspective or is not really 100% accurate in his assessment of your problem. Either way, I'd press the issue a bit. If the head is off a little gas in the combustion chamber will tell the tale better than a light. Pour it full, if it doesn't hold a valve job is indicated.

 
I've been suckered like this before, by some kid that doesn't know his ass from a hole in the ground, getting minimum wage.

Get your bike out of there!

 
Ethanol fuels can cause a slow build-up on the back side of intake valves, which could lead to gumming up the stems and causing them to sometimes stick in the guides. This is most likely to occur if you ride short trips so the true operating temperature isn't reached, riding at low revs, and having fuel that has gone "bad". Fuel with ethanol goes through "phase separation" in as little as two weeks, which means the ethanol has dissolved the water and has settled to the bottom. That is more likely to cause no start than anything.

Your dealer may not be totally full of BS, but using the term "carbon build-up" isn't likely accurate. It is more likely you have a crud build-up and/or phase separated fuel. The only real way you are going to know for sure is to pull the throttle bodies off and inspect the intake chambers, big job. I have read about a couple of guys who had stuck valves and an amazing crud build-up, but a bit higher mileage than yours.

First, drain out the fuel and put fresh in and see if it will start. Next, change your riding habits if you are doing short grocery hops and babying the bike. Go for a multi-hour ride once a month and don't be shy about revving it up. After that, use a stabilizer designed for ethanol fuels, but be aware it's a confusing marketplace out there. Also, once in a while use a product like Techron which will dissolve and clean up these deposits.

I have done a lot of reading up on ethanol fuels and what to do about it, and one day I'll put it all together and post up what I've learned. But, so far, most of the "cleaners" seem to use naptha (and/or Stoddard solvent very similar), perhaps kerosene with it. These slow evaporating solvents are best at gummy deposits. I'm not sure Seafoam is best as it also has alcohol, and you don't really want more alcohol in alcohol fuel (it will just absorb more water). There's a lot of snake oil and magic dust and opinions..... just read the labels and try to see through the marketing hype. Research MSDS sheets if they are available.

 
I have a '07 FJR with 15,889 miles. I ride the bike year round when possible and met all service requirements. I drive it at least 1-2 per month during the winter months (2-3 times a week during the other months) and the longest I have had fuel in a tank is 2 months. The other day, I pull it out the garage and it wouldn't start.... Starter works but won't fire. I drag it down to the dealership where, after 2 weeks a breakdown, they tell me that the reason is I have excessive carbon build up on my valves. They also told me that they doubt that Yamaha will cover this under the extended warrantee since this is caused by bad gas. I explained my situation and asked them what else I should have done to prevent this. They mentioned adding stabilizer but other than that they couldn't think of anything else. I said; "when? Between each fueling?" They just shrugged their shoulders. Are there any recommendations out there regarding this issue of carbon build up after 3 years and 16,000 miles. How about the issue with the extended warrantee or am I just out $1,000 plus?
Sounds like total BS. I would ride it like I stole it once a month and always use Ethanol fuel as it keeps the tank and injectors clean without adding anything else.

 
Not sure why someone would recommend always using Ethanol fuel. From what I undersatnd it adds zero benefits and a number of problems. We've just got Ethanol added to our gas here in Eastern Canada and all of the bike riders burn premium as it has no ethanol.

Agree that you need to ring that puppu out every now and then and geth the RPMs higher.

Whether they call it carbon or crud really doesn't matter, both are blank and not suppose to be there. So outside of something being totally out of whack, you're either driving it too easy or you really did get a batch of bad gas.

You haven't been adding that NOS Energy Drink to the gas have you?

 
"Bad Gas" has been a 'catch-all' for-ever for those who don't have an answer...

Why..? only you -- who got infected...? IF, there was such a thing as "Bad Gas", there'd be vehicles stranded all-over...

One thing that could've helped -- would've been the communication (from the tech to you) of the results of a compression test ("Your engine has no compression"). Then you could've decided to disassemble or not.

Compression, fuel, and spark -- the 3 things needed for combustion. Combustion is of carbon-based fuels -- incomplete combustion leaves carbon. There may have been some, on-going, issues with your FJR's fuel management that are now, finally (hopefully?), being rectified...? :unsure:

 
"Bad Gas" has been a 'catch-all' for-ever for those who don't have an answer...

Why..? only you -- who got infected...? IF, there was such a thing as "Bad Gas", there'd be vehicles stranded all-over...

One thing that could've helped -- would've been the communication (from the tech to you) of the results of a compression test ("Your engine has no compression"). Then you could've decided to disassemble or not.

Compression, fuel, and spark -- the 3 things needed for combustion. Combustion is of carbon-based fuels -- incomplete combustion leaves carbon. There may have been some, on-going, issues with your FJR's fuel management that are now, finally (hopefully?), being rectified...? :unsure:
Therein lays the dilemma. I am not a “hard” rider by any means. I do cruise and that is why I bought a sport cruiser and not a sport bike (at least I thought so). I live in northern Kentucky where the winters are bit chilly for my blood to ride however; I still get it out on those clear days of 10-20 degrees and take it into work (40 miles roundtrip). On the way home, there is a stretch of road that I like to open it up and I try to do so which is at the tail end of my commute. During the summer, I ride this ride 2-3 times a week (weather permitting – do not prefer to ride in thunder showers although I have been there a time or two). Each Sunday a group of us run to breakfast at a little place that is 60 miles away, grab my pancakes and head home. That riding time is from about now until October. My longest ride has only been 400 miles one way. From what I am gathering, I will need to spend more time in 4th gear and run it past 5K rpm, use an additive here and there, use premium fuel (without ethanol) and find another mechanic… All of which are not mentioned in the owner’s manual. I will see tomorrow where my fate lies with Yamaha to see if their Yamaha Extended Service (YES) plan really means that YES they will stand by their product. I have owned 5 Yamahas and ridded 45 years and never had this issue prior. Granted, my motocross days are over but it never dawned on me to run this bike up in the 6-7K rpm range to avoid a costly repair. The mechanic did call me and tell me that my compression was down in the 60 range and should be at 200. The week prior I was near redline in 4th and doing XXX mph (you guys can do the math)… The next week… nothing. I appreciate all of your input and all of it has helped me though this time… ride on!

 
Jam'n,

Sorry you have to go through all this and hope this is your last event.

Do keep your RPM's up along with good quality fuel and sure this won't happen again.

May the Force Be With You on Monday or Tuesday!

P.S. If you think you are not being told the Whole Truth, Call your Regional Yamaha Service Manager and see if they will monitor your situation with the dealer. You can call 800-962-7926 Yamaha Customer Service-Cypress/CA

find out who it is.

 
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