carbon buildup @ 3000 mi

[rodger]

while stored for the winter I start my fjr every 2 weeks and warmit up till it comes up to temp.In Jan it wouldn't start seemed to have no compression, I have an extended warranty, so ,Dealer time.

It's an 2006 with 3,000mi Iam a cre giver for my mother and limited time to ride. after the teardown of the top end the combustion chambers were full of carbon which had stuck under the valves ,0 #1 ,23#2,85#3,136#4 compression.

they cleaned it ,did a valve job ,all new seals,put it back together.I am bothered by the explanation I was given.

I have worked on engines all my life and can't grasp what the dealer said the Yamaha rep has explaned to them.

I was told this was caused by an extreme lean condition , the engine was subtly misfiring and building up carbon in the engine to the exrent it filled the cyl.and flaked off causing the valves to not close and thus no compression .

I have seen lean conditions burn valves ,hole pistons,and crack heads but can't reallygrasp this explanation.

Iam wary of the machine now although it runs welland handles great, but don't want to experience the cost of this if ti happens ina year or two.

Anyone else experience this?

Rodger

 

[charismaticmegafauna]

<snip>stored for the winter I start my fjr every 2 weeks and warmit up till it comes up to temp.In Jan it wouldn't start seemed to have no compression, ...2006 with 3,000mi ...the combustion chambers were full of carbon which had stuck under the valves ,0 #1 ,23#2,85#3,136#4 compression.

they cleaned it ,did a valve job ,all new seals,put it back together.I am bothered by the explanation I was given.

Anyone else experience this?

Rodger

Sad story, Rodger. And, yes it happens (and has even been reported on this Forum).

Low compression (compession test) tells the tale. But, if you could've somehow gotten it running -- some of the carbon build-up may have been removed/blown-off by running (the harder the better)? But, maybe not -- some may have just taken-up permanent residence on the valve face or valve seat. There are after-market combustion chamber carbon-removing chemicals available. They usually require some engine running to be effective -- so, if there's not enough compression to start, it's a classic "Catch-22".

I don't really understand the 'cause -- reasoning' you were given, either. But, suffice to say: modern high-performance, high-horsepower, engines probably need more 'excersize' than -- less-than 1000 mi/year for good, reliable, long-term performance? It is sad that these types of M/Cs sometimes don't take well to limited/sporadic use.

My standard response to issues like this is: "Ride it to Minot -- and don't spare the horses."

Good luck in the future.

 

[Bungie]

Iam a cre giver for my mother and limited time to ride.

I'm in the same boat, I can't tell you how many trips I've had to cancel at the last minute because of this. I lucked out for EOM last year, and I've got my fingers crossed for both EOM and CFR this year. She has lung cancer and COPD (ephysema) and really is week to week.

That being said, you've got to see if you can make arrangements to enjoy life - for your own sanity!

Hope you get good news on the bike!

 

[SkooterG]

I ain't no expert, but are the no load winter warm-ups doing more harm than good?

BTW, did they say WHY your FJR has a subtle lean misfire condition?

And for all you fart smellers out there, what causes carbon build-up?

 

[radman]

I ain't no expert, but are the no load winter warm-ups doing more harm than good?
BTW, did they say WHY your FJR has a subtle lean misfire condition?

And for all you fart smellers out there, what causes carbon build-up?

The winter routine could very well have done it, or at least contributed. The lean condition can do it by misfires, a lean load won't fire followed by an overly rich load that fires but poorly-and a cylinder that really never gets good and hot as a result-this is different than a constant firing on the lean end of the scale and under load which can raise chamber temps beyond design and melt spendy stuff. Carbon build up is normal, high chamber pressures and heat minimize, high load and temps (fast hard running) can blow some out, but overwhelm the system and build up occurs, and carbon begat carbon (carbon attracts carbon). This is why race motors will have highly polished chambers and valve heads, to try and prevent carbons purchase. Carbon also can have a glow plug effect in that as a sharp edge of it is heated, it can glow and prematurely light off the incoming mixture, causing a pre-ignition knock.

 

[charismaticmegafauna]

And for all you fart smellers out there, what causes carbon build-up?

Incomplete combustion -- all the molecules aren't combining fully with all the other molecules....

When your header-pipes are glowing cherry-red and your tail-pipes are white inside -- you're getting there...!

 

[RadioHowie]

I ain't no expert, but are the no load winter warm-ups doing more harm than good?

I'd hazard a guess that the key to your reply is "no load". Since the bike IS starting in the fast-idle/rich run mode whenever it's cold, it's dumping a considerably larger amount of fuel into the combustion chambers. And that can certainly lead to carbon buildup. Without goosing the revs up (after complete warm-up) that carbon is gonna sit there, building up more and more with each cold start, IF it doesn't get a chance to get "cleaned out" with a good normal-load run. That seems fairly logical to me.

BTW, did they say WHY your FJR has a subtle lean misfire condition?

Just a wild ass guess, 'cause Rodger didn't specify where he stores his bike, but cold will definitely cause moisture trapped in E10 gas to precipitate out, and since the fuel pump pickup IS in the bottom of the tank, water in the fuel is gonna hit the injectors first and cause misfires.

And for all you fart smellers out there, what causes carbon build-up?

I'd say you probably nailed it in your first question. But even a winter's worth of no-load starts doesn't seem like it could create enough carbon build-up to block the valves.

Now rust....THAT'S a different story!

 

[rodger]

I ain't no expert, but are the no load winter warm-ups doing more harm than good?

I'd hazard a guess that the key to your reply is "no load". Since the bike IS starting in the fast-idle/rich run mode whenever it's cold, it's dumping a considerably larger amount of fuel into the combustion chambers. And that can certainly lead to carbon buildup. Without goosing the revs up (after complete warm-up) that carbon is gonna sit there, building up more and more with each cold start, IF it doesn't get a chance to get "cleaned out" with a good normal-load run. That seems fairly logical to me.

BTW, did they say WHY your FJR has a subtle lean misfire condition?

Just a wild ass guess, 'cause Rodger didn't specify where he stores his bike, but cold will definitely cause moisture trapped in E10 gas to precipitate out, and since the fuel pump pickup IS in the bottom of the tank, water in the fuel is gonna hit the injectors first and cause misfires.

And for all you fart smellers out there, what causes carbon build-up?

I'd say you probably nailed it in your first question. But even a winter's worth of no-load starts doesn't seem like it could create enough carbon build-up to block the valves.

Now rust....THAT'S a different story!

 

[rodger]

I ain't no expert, but are the no load winter warm-ups doing more harm than good?

I'd hazard a guess that the key to your reply is "no load". Since the bike IS starting in the fast-idle/rich run mode whenever it's cold, it's dumping a considerably larger amount of fuel into the combustion chambers. And that can certainly lead to carbon buildup. Without goosing the revs up (after complete warm-up) that carbon is gonna sit there, building up more and more with each cold start, IF it doesn't get a chance to get "cleaned out" with a good normal-load run. That seems fairly logical to me.

BTW, did they say WHY your FJR has a subtle lean misfire condition?

Just a wild ass guess, 'cause Rodger didn't specify where he stores his bike, but cold will definitely cause moisture trapped in E10 gas to precipitate out, and since the fuel pump pickup IS in the bottom of the tank, water in the fuel is gonna hit the injectors first and cause misfires.

And for all you fart smellers out there, what causes carbon build-up?

I'd say you probably nailed it in your first question. But even a winter's worth of no-load starts doesn't seem like it could create enough carbon build-up to block the valves.

Now rust....THAT'S a different story!

the fjr is stored in a heated garage , I ran it for about 15 ro 20 min being sure it was warmed up well and reved after it was warm,the trips during riding season go at least 20 miles and run 4 lanes at 65 /70 mph.The lean settings were factory, and after top overhaul the FI was set to specs. Shop Mechanic said it came from factory extremely lean and had to enrichen to spec on the exhaust emission readings.

I like the thoughts of the fuel picking up moisture,adding to the misfire. I would have thought the lean condition would have been caught @ 600 mi. I store the fuel with an additive to keep it from breaking down,but might be better to figure how to drain the tank. Thanks for the replies ,I'll run it harder and forget the winter start ups.

Thanks,

Rodger

 

[RadioHowie]

I like the thoughts of the fuel picking up moisture,adding to the misfire. I would have thought the lean condition would have been caught @ 600 mi. I store the fuel with an additive to keep it from breaking down,but might be better to figure how to drain the tank. Thanks for the replies ,I'll run it harder and forget the winter start ups.Thanks,

Rodger

BAD idea, unless you fog the tank with a healthy dose of WD-40 or something like that.

HERE'S the story of an FJR left sitting too long with an empty, UN-fogged tank.

Keeping the tank full with stabilized fuel is a MUCH bettter idea.

Maybe Yamaha's tech did hit the problem. Best of luck in the future.

 

[Bogus]

This is the proper way to clean your engine of carbon deposits!

 

[HotRodZilla]

Well, that motor got warm...No doubt about that! Sheesh.

 

[Bulldog9]

I've never been a believer in the 'start it once a month' club. During the winter months when I cant ride, If my bike will sit more than a month I will leave it with a full tank of stabilized fuel, and either hook up a battery tender or disconnect the battery completely. If I cant start it and ride, I wont start it. Fresh oil is a plus too. Been following this since 1984 or so on my XS1100, never had a carb, fuel tank or carbon problem.