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Let's Ride!!
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Discussion Starter #1
So back on March 12th I was out on a group ride. We were riding VERY spiritedly: I had it pegged at about 105. All of a sudden I had a loss of power. Pulled to the side of the road, and as I slowed the engine died. Started it back up and there was a terrible sound in the front cylinder. Tried to limp it back to civilization, but didn't make it very far before there was a loud thud/crunch and the engine seized.

Since then, I hadn't gotten around to finding out what the problem was, simply because I just didn't want to know/see how bad the damage is.

Well, I finally started taking it apart this week. And it's just as bad as I feared.

Drained the oil and found a lot of metal flakes in the oil screen. That's a bad sign:


Got the engine out (God it's such a pain in the ass to remove the engine!) and took off the valve cover. Immediately saw that two rocker arms were not on their valves. Not sure if that happened before or after I removed the engine.



Pulled off the cylinder head, and the badness is immediately obvious:


Get the cylinder off, and it's even worse:





Plenty of metal pieces down in the bowels of the engine too:


Looks like I've got my work cut out for myself to get it going again. But I know I can get it done. Just a matter of time, money, and effort. Worst part is that I'm off the road during the prime riding season. Sucks.

I'll update with more photos as I keep going.
 

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Senior Member
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OUCH, sorry for your bad luck, good pics though. :doh:
 

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Concert connoisseur
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so sorry to see that, good luck with the rebuild!
 

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Registered
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That sure left a mark! Hey can I use your VN900 seat while you re-build? (Figured that you needed some humor cause you got to be crying deep down inside.)
 

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Registered
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120 Posts
New head, piston, sleeve rod, bearings, and that just what we can see. Might be time to part it out and buy a new bike.
Do you know what happened? Did you throw a cam chain or something?
 

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Linkmeister Supreme
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7,960 Posts
Wow Dave, that`s a kind of bad luck, good luck story.
Bad luck that the engine broke, but good that it didn`t seize solid while you were traveling at a buck five.
That would have made the ride so much more...mmmmm...interesting....than you needed.

I will be watching to see what else you discover here, as to why it broke in the first place.
Good luck with a speedy and solid fix.
 

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The Reanimater
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Linkmeister Supreme
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Let's Ride!!
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Discussion Starter #12
OK, finished getting it torn apart. Got all the large pieces out. You can see there are a whole bunch of little fragments that were floating around (or maybe not) in the oil. I'll have to take great care to make sure I get every last little one out.




Now, there is some further damage to the insides of the crank case. Here you can see that something damaged an internal oil line. Not sure if I can un-flatten it, or if I will need to get a fresh one. I'm figuring new one.


Then there was also some damage to the crank case itself. Something flying around (most likely the damaged connecting rod) impacted what I can only describe as a shelf and broke a chunk off. In looking at the case, I can't see how that would negatively impact the operation of the bike if I were to just leave it and put it back together. Any opinions?


All in all, I think more than ever that I can rebuild it by just replacing the damaged parts and be good to go. I've already got a replacement connecting rod, and the used cylinder and piston should arrive in the next couple days. In the meantime, I'll clean it out real good and start putting it back together so that all that's left is to put on the new piston and cylinder and then reinstall the engine.

I'll let you know when I get it finished how it all goes.

Also, so far I can't yet figure out what caused all this in the first place. Someone at the time said it sounded like I'd thrown a bearing, but there is no loose bearing anywhere. My guess at this point is that the cylinder cracked from the stress, causing the loss of compression in that cylinder. Maybe even a chunk came out. That unsettled the piston, which accounted for the noise at the time. As I was trying to limp it back, the cylinder disintegrated further, causing the piston to impact an edge, causing it to explode and damaging the connecting rod at the same time. That's about the best I can come up with so far.
 

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Let's Ride!!
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Discussion Starter #14
Yeah, I've seen that engine as well. It says that the engine is seized. MY engine was seized. So I'd be concerned that similar or worse damage would be awaiting me in that engine. Hell, what if it had the same damage as mine? Then I'd have wasted 300 bucks on a useless "spare" engine.

I'm not opposed to doing the work. Hell, if I had the extra money, I'd consider buying that one, rebuilding it, and then reselling it. But for an engine that doesn't function and may take as much or even more work to get it going? I'm not going to take that chance.
 

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Let's Ride!!
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Discussion Starter #16
So two things:

-There is a lot of carbon build-up on the "good" piston, as well as on the valves. What's the best way to clean that off? In some videos I was watching, someone (from this site?) used oven cleaner and elbow grease to clean his valves. Can the same be used on the piston head?

-I've posted this same stuff on another site I frequent (bayarearidersforum.com) and one person is saying that based on what he's seeing I should just stop now and find a running used engine instead. Anyone concur with that assessment? Or can/should I go ahead with the rebuild?
 

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Senior Member
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With the internal damage, I would try to find a used engine. Never know what else might be stressed in there because of this.
 

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Let's Ride!!
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Discussion Starter #18

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Let's Ride!!
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Discussion Starter #20
I sent that person a message a while back asking what was wrong with the engine. He basically responded "it's there in the ad". Not real helpful. Seems he hasn't explored why it has seized, and doubt he will.
 
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