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Motor blew up


Oldschool

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wanted to advise...mine only had 8000 miles on it. Changed oil and filter every 2000 miles. Set shift light 500 rpm below rev limiter. I'm 68 years old and do not flog the shet out of it.  I do ride out wheelies. I got no help from Yamaha because it was 24 months past warrante. First thing I heard from the shop was they won't like that after market oil filter ( a K&N ). I'm pretty sure I dropped a valve and it broke the rod , blew a hole in the front of the case and even busted the back of the case at the starter mount all at 70 mph in traffic. I really love this bike and got another engine but it did piss me off about the comments I received from customer service. Has anyone else had any valve issues. 

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Sorry to hear your motor granadeing like that.  😢 That behavior is definitely not the norm.  I'm not aware of any known issues with the motor other than occasional side cover leaks having cropped up.

DewMan
 
Just shut up and ride.

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Every oil chance was clean. It never made any noise and it ran strong. My son has one also and mine was about a bike and a half faster with an extra 40 lbs on it too. There was no signs of any issues. I've been riding since 1967 an have never had an engine blow up including dirt racing so well. 

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Shift light?   Did you add that?  Yours the first one I have heard of blowing up, except for one that was very highly modified for racing.  He broke a rod. 

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17 hours ago, Oldschool said:

Every oil chance was clean. It never made any noise and it ran strong. My son has one also and mine was about a bike and a half faster with an extra 40 lbs on it too. There was no signs of any issues. I've been riding since 1967 an have never had an engine blow up including dirt racing so well. 

An oddly powerful motor can also be a sign of loose tolerances on the guts. It will make less friction at higher rpm when the hydrostatic forces of the oil get to work, but it can increase wear at lower rpm when the oil cannot support the parts as well. 

 

Did you keep any of the oil from previous oil changes? On the off chance you did, a lab like Blackstone may be able to find something in it, too. 

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The oil pickup screen is near the bottom of the oil pan, when the bike is on 2 wheels. But where is the pickup in relation to a new oil level when the bike is vertical up on it's back wheel? 

 

In other words, can the motor be starved of oil while doing long, straight-up wheelies.  

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With the number of units made, there is bound to be material and/or assembly mistakes/failures here and there. I don't think you did anything wrong, you just had bad luck. However, I personally would contact Yamaha USA and explain the mileage, use and what happened. If they won't listen, I'd try Yamaha Japan. In Germany, it is quite common for importers to fix things out warranty on "kulanz", that is sort of a friendly gesture where they accept responsibility to a certain degree, from 10 to 100 %. Quite often, they will supply the parts, but not warrant the work. We have the same situation in Norway, where it's called "reklamasjon". A warranty, at least hear, means they must fix the thing unless they can prove gross negligence. But if a part is expected to last let's say 5 or 10 years, you can claim compensation even if you do not have a warranty when a product fail to meet its minimum expected life.

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In Australia, the yamaha dealers are more likely to have un-kulanz. A non comercial gesture is most unlikely to happen. It's money all the way ( and reputation be dammed).

And I agree with rick, long wheelies and oil pickup are relatively mutually exclusive. Modern synth oils can usually stick long enough but it's possible the 07 has a relatively dry spot somewhere.

Go forth and modify my son...go forth and modify...

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21 hours ago, mjh937 said:

Shift light?   Did you add that?  Yours the first one I have heard of blowing up, except for one that was very highly modified for racing.  He broke a rod. 

My rod busted too even cracked the top of the casing under the starter. I had it flashed for my yoshi full exhaust, quick shifter, and shift light. The oil was super clean the last three times. I think I dropped a valve and got it all started. I got the motor out today what a job...I have pics of the hole in my case but don't know how to attach them.

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22 hours ago, mick97702 said:

Shift light? Is that a feature on the EU models or a mod? If a Mod, any other mods done?

Mod. quick shifter, full exhaust, flashed for the exhaust. And cosmetic stuff.

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3 hours ago, gregjet said:

In Australia, the yamaha dealers are more likely to have un-kulanz. A non comercial gesture is most unlikely to happen. It's money all the way ( and reputation be dammed).

And I agree with rick, long wheelies and oil pickup are relatively mutually exclusive. Modern synth oils can usually stick long enough but it's possible the 07 has a relatively dry spot somewhere.

I was told by a very reputable dealer mechanic that the new bike have a baffle or some system that allows oil support doing wheelies. I can say that I do a lot of wheelies through third gear most of the time. But this day was spent in the twisties never got past 4th gear. I just got a bad engine. I've raced and drag races high performance cars. I know what excessive sustained high RPM can do. I never abused this motor in any way. I'm doing the change myself and I give up on any thought of compensation. I love this bike though. I sold my ZX14 after I got this and I do miss the excerlation but that is all. This bike is a blast just what I've always tried to make out of my other bikes. I'd buy another one in a heart beat. That was just a bad day. I even had a big ass deer shoot out right I  front of me at 70 mph. That morning. I never touched my brake it was so fast and so close. 

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To be honest , this bike has such conservative camming and spark curve , that over-reving is not really going to do much I would think. It pretty much closes down the power well before anything nasty can happen. It's no CBR250RR! ( mind you they don't blow up either...no idea how they manage to last).

Go forth and modify my son...go forth and modify...

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Sorry to hear about your bike. An undetectable, microscopic flaw/weak spot the metal that weakened more and more over time and finally broke??? It's what brings air planes and choppers to the ground in a hurry sometimes. GL with your rebuild.

What you said about this bike is priceless (I feel the same way) and something many people should understand/consider before they go selling this bike to get another, even one with more power. "This bike is a blast just what I've always tried to make out of my other bikes. I'd buy another one in a heart beat."

Beemer

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I am curious, does the 18 MT-07 have a baffle in the pan to keep oil to the pump intake or not? 

 

And, those of you experienced with this engine, how long can you wheelie the thing before it truly starves of oil?

 

I am 64, grew up riding and though I had a 15 year hiatus, I can ride this little mofo like it is a freaking dirt bike! This thing begs to be on one wheel, rear or front for that matter. 

 

But I can reign it in if it is going to grenade my engine---?

 

I guess I will do an air cooled and dry sump Monster next time I talk my wife into allowing me to get a motorsickle, lol.

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7 hours ago, 3crows said:

I am curious, does the 18 MT-07 have a baffle in the pan to keep oil to the pump intake or not? 

 

And, those of you experienced with this engine, how long can you wheelie the thing before it truly starves of oil?

 

I am 64, grew up riding and though I had a 15 year hiatus, I can ride this little mofo like it is a freaking dirt bike! This thing begs to be on one wheel, rear or front for that matter. 

 

But I can reign it in if it is going to grenade my engine---?

 

I guess I will do an air cooled and dry sump Monster next time I talk my wife into allowing me to get a motorsickle, lol.

Don't think anyone's gonna be able to answer those questions. We're all just guessing to the cause of this failure. If it was an SV650 Suzuki, well, they have a reputation for wheelie induced motor explosions. The FZ's motor does not and has been very,  very reliable. 

 

As to baffles to prevent oil from sloshing about, well, there's only so much they can do to overcome gravity. It really more depends on where the oil pickup is in relation to the new oil level and how much oil the cam lobes continue to see when the bike is vertical.  

 

A dry sump isn't exactly fool proof either when it comes to lubrication issues when the bike is vertical. Yeah, the pump that provides the oil pressure will likely not get starved, but the scavenge pump inside the sump - the one that returns oil to the external tank - will start to suck air allowing too much oil to stay in the crankcase. When you bring the bike back down to earth, that extra oil can be hit by the crank and flung about causing problems. 

 

Another thought (it's raining too hard to go look) -  iirc, the overflow tube on the coolant reservoir is at the back of the cap. it might be possible for coolant to leak out with that bottle tipped 75 or 80 degrees every time you wheelie. You'd never see any drips and if you don't check that bottle often, you'll not see it until the bike overheats. Assuming you have the dash set to see engine temp - something it should always do, imo, you could miss the early signs. Considering just how little coolant is in the system to begin with - well, bad stuff happens fast.  

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1 minute ago, 3crows said:

I wonder if the instrument cluster oil light is an oil low pressure light or is it an oil low level light? What exactly does it indicate?

pressure. Definitely don't want to see that with the engine up in the revs. 

 

Wheelies, lol, guess that's one way to get the cluster closer to eye level,  

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OP, I wish you good luck. Hope it works better this time out. You are definitely right, this little MT-07 is like a barrel of monkeys it is so much fun. A cheap, easy date with tons of personality and good looks, what could be wrong with that!

 

I do not much believe in lemons but I guess tolerance build, an engine could get out that is not optimal. 

 

Usually there is a cause. Well, there is a cause, we just do not know what it is.

 

As far as wheelies and me, my wife allows me to have another motorcycle only if both wheels stay on the ground, at the same time, and I just ride slowly about up in the low density country side we live about. I can do that. But, the little MT-07 does a power wheelie by accident in first and second and I think it will lift in third with perhaps some gentle urging. 

 

James

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