fried valve at 56,000 miles

[johnmark101]

9 hours ago, rustyshackles said:

  Valves were checked at 26k and I think in spec but I need to find the paperwork.  

From what I have read, on this particular engine, just about everyone had tight valves at the first valve inspection.  Would be unusual to find them all in specification at 26,000 miles.  Like others here, I suspect that the issue lies with the work done by the dealership.  

Like many here, I am extremely cautious about letting someone else work on my bike.  I have a 2013 Ninja 1000 in addition to the Tracer.  I skipped the first valve inspect because the bike runs so damn well and most on the forum found nothing out of spec at 16,000 miles.  I let a local shop do the first inspection at 33,000 miles.  Five valves needed new shims.  Bike still runs perfectly but now I have an intermittent electrical gremlin that never existed before the shop worked on the bike.  The shop insists they have nothing to do with this.  🤬   

[koth442]

Sorry for you loss Rusty. 

[chitown]

That's disappointing. 

Would definitely be curious to see the measurements from the first valve check. Like many have reported my '15's intake were fine but several tight exhaust valves at first check performed well ahead of schedule. 

 

 

[peteinpa]

Maybe that's the magic question: Has anyone had burnt exhaust valves that did their own work?

With dealers unable to correctly assemble brand new bikes (and charge you for it) can they do a complex valve adjustment?

Untill now I had a long line of Hondas. They never changed clearances as long as I owned them. I checked them myself.

The only ones that would need adjustment were the screw and locknut type.

The V4 Hondas got a rep. of galling cams. I never had that problem. I wonder if the ones that had problems were "checked" by dealers. 

I've heard too many stories of a piece of hidden tape on the valve cover being undisturbed by a dealer valve check.

$600 to set your bike in the corner for a week. "valves are in spec."

[gv550]

After reading about many owners finding tight valves at the first check, I went in early to measure mine. At 30,000 kms all the exhaust valves were below the minimum and one was close to no clearance. That valve required the thinnest shim available so any future adjustments would require removal of the head and replacing the valve and/or seat. I traded the bike off a month later.

[peteinpa]

31 minutes ago, gv550 said:

After reading about many owners finding tight valves at the first check, I went in early to measure mine. At 30,000 kms all the exhaust valves were below the minimum and one was close to no clearance. That valve required the thinnest shim available so any future adjustments would require removal of the head and replacing the valve and/or seat. I traded the bike off a month later.

That's encouraging. ☹😭

[micah2074]

2015 with almost 100K miles. Clearances checked at 26K , 52K, and 78K miles. She runs as good as the day i got her with 6 miles on the clock. 

[betoney]

17 minutes ago, micah2074 said:

2015 with almost 100K miles. Clearances checked at 26K , 52K, and 78K miles. She runs as good as the day i got her with 6 miles on the clock. 

Nice!  Here's to another 100k trouble free miles...  🍻

[nhchris]

6 hours ago, mikerbiker said:

Who did the ECU flash?

I know this might sound like heresy to many here,  but IMHO ....

An ECU flash and free flow exhaust radically alter engine dynamics and operating parameters.  The long term effects of which are untested and unknown.  Removed O2 sensors, block off plates, boosters, etc. add to the unknowns.

Like all engine manufacturers,  Yamaha R&D and QA have run the CP3 in stock configuration through thousands of hours and probably millions of miles of torture testing. Certainly more than 50k miles worth.

Maybe some of the stock fuel mapping was designed to cool exhaust valves with a pulse of fuel at certain RPM.  Maybe timing and advance setting were specified not for ultimate HP but for valve train longevity.  We just don't know how the designers and engineers tweaked the motor to be fast but still reliable.  It's always a bit of a trade off.

There's a lot more to engine operation than a maxed out dyno chart.  And I am sure any of the aftermarket ECU flashers will tell you you're own your own if problems occur 50k miles down the road.  Caveat emptor.

(No flames please! 

[rustyshackles]

For those (like me) who lack the tools, time and know-how to DIY paying someone is the only option.  I live near a big city yet independent mechanics are scarce, which leaves dealerships.  

What's the answer?  Maybe keep selling or trading bikes just before they hit serious maintenance milestones like valve adjustments.    

[pilninggas]

24 minutes ago, nhchris said:

I know this might sound like heresy to many here,  but IMHO ....

An ECU flash and free flow exhaust radically alter engine dynamics and operating parameters.  The long term effects of which are untested and unknown.  Removed O2 sensors, block off plates, boosters, etc. add to the unknowns.

Like all engine manufacturers,  Yamaha R&D and QA have run the CP3 in stock configuration through thousands of hours and probably millions of miles of torture testing. Certainly more than 50k miles worth.

Maybe some of the stock fuel mapping was designed to cool exhaust valves with a pulse of fuel at certain RPM.  Maybe timing and advance setting were specified not for ultimate HP but for valve train longevity.  We just don't know how the designers and engineers tweaked the motor to be fast but still reliable.  It's always a bit of a trade off.

There's a lot more to engine operation than a maxed out dyno chart.  And I am sure any of the aftermarket ECU flashers will tell you you're own your own if problems occur 50k miles down the road.  Caveat emptor.

(No flames please! 

While the effects of a reflash, and an altered fuel/spark map, can never be ruled out, it has to be said that most make the engine run richer (because emissions regs set fuelling towards 14.7:1) which gives smoothness and more power. Broadly speaking exhaust gases are significantly hotter with a leaner burn (it's why exhaust gas temperature can be monitored using an EGT probe and used to tune fuelling) and this is much more likely to burn an exhaust valve out.

I'd still be inclined to think that someone hasn't got the maths right and has put the wrong shim in and not done the double check. The valve has then not been seated during combustion events and got burned to buggery.

[Salish900]

49 minutes ago, rustyshackles said:

For those (like me) who lack the tools, time and know-how to DIY paying someone is the only option.  I live near a big city yet independent mechanics are scarce, which leaves dealerships.  

What's the answer?  Maybe keep selling or trading bikes just before they hit serious maintenance milestones like valve adjustments.    

Maybe so, and let me urge you then, never purchase an Aprilia! Don't ask how I know this. 

[peteinpa]

2 hours ago, pilninggas said:

While the effects of a reflash, and an altered fuel/spark map, can never be ruled out, it has to be said that most make the engine run richer (because emissions regs set fuelling towards 14.7:1) which gives smoothness and more power. Broadly speaking exhaust gases are significantly hotter with a leaner burn (it's why exhaust gas temperature can be monitored using an EGT probe and used to tune fuelling) and this is much more likely to burn an exhaust valve out.

I'd still be inclined to think that someone hasn't got the maths right and has put the wrong shim in and not done the double check. The valve has then not been seated during combustion events and got burned to buggery.

I also look at a reflash as a good thing. To meet emissions the MFGs must run the engines doomsday lean. Then the new owner puts on a pipe without a reflash and it's even leaner. THIS makes it run stupid lean which kills engines.

I'm never going near a 2021 bike. New regs are way crazy.  I don't get it, out on the road a truck, bus, etc. pukes out a black cloud but my little bike can't pollute. 

[peteinpa]

18 hours ago, rustyshackles said:

 

Now planning my next move.  I shouldn't write off Yamaha but I feel betrayed. 

Vinnies new head is still in the parts for sale section. Just need new valves, the rest transfers over.

Cheapest way to go.

[Ride On]

It's well known in the aviation world, where the pilot controls the fuel/air mixture, that lean of peak operation (lean of peak exhaust gas temperature (EGT)) results in a cooler and a more efficient running engine. 

The maximum cylinder pressure and cylinder head temperatures occurs at peak EGT (14.7:1), but we're prohibited from running aviation engines there, (5,000 foot elevations and below) even though that's where the most horsepower is made.  Instead, and at a slight horsepower penalty, these engines are required to run at a minimum of 50 degrees lean of peak, or 50 degrees rich of peak, but never at peak EGT.   Many aviation engines don't have a balanced fuel delivery system though, and can't run smoothly lean of peak, so those engines are limited to operating at the more inefficient rich of peak operations. 

For years I flew behind a turbocharged, 520 cubic inch Continential.  Once reaching crusing altitude, I'd push the throttle wide open while simultaneously pulling the mixture control through peak EGT and immediately leaner by another 75 degrees or so, just before the engine ran rough.  This saved about 3 gallons per hour compared to running 50 degrees rich of peak, all while making the same horsepower and at cooler cylinder head and exhaust gas temperatures.  You would literally see the immediate temperature drop on your instruments as you go lean of peak, and also relative to operating at 50 degrees rich of peak.  Operating lean of peak was actually learned in WWII, when bombers were trying to extract every last drop of fuel efficiency to make it back to their airfield. 

Back to present day...  On takeoff and climb through 5,000 feet (as opposed to crusing altitude outlined above) a different strategy is used, and we are required to run the mixture full rich at full throttle.  Though maximum power is available at peak EGT, operating there is prohibited by all aviation engine manufactures due to the risk of preignition and excessive cylinder head temperatures.  Running full rich is for engine cooling purposes and insurance against preignition even though there's a horsepower penalty.  Efficiency here is terrible.  In my case I'd burn 34 gallons per hour at takeoff.  That compares to 15.3 gallons per hour at cruise, set lean of peak (approximately 70% horsepower).

That's the aviation world.  I suspect the engines in our Yamahas are set up similarly.  If so, then under wide open throttle Yamaha mapped the engine to run rich, at a small horsepower penalty, for reliability purposes.  An ECU tune can get that performance penalty back but, the question is, at what cost to long term reliability?