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Discussion Starter · #1 ·
2012, 47,000 miles. Stock except the fairings, lights, and slip-on.

I started my bike up on a cold morning and rode to work. It started a tiny bit harder than normal, but I assumed that it's because it was cold (about 40F). It seemed to ride fine; there was no unexpected noise, no apparent loss of power. When I was about to head home, I found a nail in my tire, and had to get a ride home. I brought in a pump the next day so I could get to the shop, and my bike wouldn't start. It seemed to be turning over, but not catching. I check the obvious things--neutral switch, kickstand sensor, clutch sensor--but it wouldn't start. It stayed at my workplace for about a week until I was able to get a truck to take it the mechanic.

The mechanic found that the wiring harness had been chewed through. So, new harness. When he tried to start it, he was getting spark, but it wouldn't catch. It failed a compression test--all cylinders were below 100 psi--and the only cylinder that was marginal on the leak down test was the 1st. I believe he said it was the intake valves. He said that the timing was good, and that the cam chain hadn't jumped, and that the valve clearances were good. His best guess without dropping the engine is that that the valve seats are bad.

It was overfull on oil; I'd been getting a low reading, had added oil, then been getting a high reading, and hadn't drained oil out yet. I'm assuming--perhaps falsely--that the engine didn't seize due to oil frothing and low oil pressure cause by overfilling, because it does seem to be turning over. I've been getting timing chain noise, and have an APE tensioner, but haven't installed it yet because I'm currently replacing the engine in my car. (...Which failed due to the timing chain.)

There's no evidence that the head gasket blew; there's no coolant where it doesn't belong, and engine temp has been consistent. If the head is cracked, I have no idea how, since I haven't crashed or dropped it. There are no error lights on the display.

So, several questions:

First, WHY? It seemed to run normally, and then very suddenly it didn't. If the timing chain had jumped when trying to start, I'd completely get it; the pistons would have collided with the valves, scored the cylinder walls, and I'd need a new engine. But that shouldn't be the case if it's in time. Instead, it seems like the compression went from good enough to start and run in a way that seemed normal to no compression at all overnight.

Second, are there other possibilities for the failure? If so, what?

Finally, I'm reasonably mechanically adept, but I am fairly poor, and crap at diagnosis. I'm already at about $400 in labor, and it sounds like I'll be at about $1100 by the time this is done if I have the mechanic do it. I'm k-swapping engines on a Civic, and I've done all my own mechanical work on my bike up to this point, but I've never completely disassembled a head or block. Is it a good idea or a bad idea to try and do this myself, if this is, in fact, just a valve seat regrind on the head? (I assume that I should plan on buying new intake valves as well.)
 

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As soon as the oil pressure got out of range your oil pressure light would turn on. They're fairly sensitive.

No start condition for you seemed to be the munched harness. Some rodent may have lunched it while parked.

I'd be tempted to get a second compression check somewhere else 'cause this ain't makin' sense. From fine to all low with no symptoms just ain't likely.

But if it is what you're saying I'd pony up the $1k or so and just buy a motor. You can do the swap yourself and given how high mileage yours is it's not just a repair, it's an upgrade.
 

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Discussion Starter · #3 ·
As soon as the oil pressure got out of range your oil pressure light would turn on. They're fairly sensitive.

No start condition for you seemed to be the munched harness. Some rodent may have lunched it while parked.

I'd be tempted to get a second compression check somewhere else 'cause this ain't makin' sense. From fine to all low with no symptoms just ain't likely.

But if it is what you're saying I'd pony up the $1k or so and just buy a motor. You can do the swap yourself and given how high mileage yours is it's not just a repair, it's an upgrade.
The no-start condition is unclear. A rodent definitely chewed through the harness--the bits of nesting fluff on top of the ECU along with the chewed harness prove that--but it's unclear whether that happened when my bike was sitting at work for a week, or whether it was overnight between when I rode in and when I tried to start it the next day. Given that the only thing the mechanic did to start was replace the harness, and it still wouldn't start (good spark, fuel in the cylinder), I don't think that was the actual problem.

Someone else suggested that it could have been low compression when I started it (and it did start a little hard, which I'd assumed was the cold), and that the ride to work was enough stress that there wasn't enough compression to re-start it, either the next day (if the harness was still intact by then) or after the mechanic replaced the harness. Does that sound plausible, or improbable to you? It's possible that I've been riding it with low compression since I bought it; when I got it, it had 18,000 miles, had never previously registered anywhere in the US and was a stolen-vehicle recovery--ran a VIN check as part of the bonded title process--and had evidence of being crashed at least once (rash to bar ends and levers), so it might have been a track bike that was beat to ****.

Used engines on eBay are currently running more like $1500-2500 for a '07-'12, and none of the engines listed yesterday when I checked list compression values (and at least one is in the 35,000mi range). Eventually I should buy a new (used) engine so I can be working on rebuilding one while riding the other, but with other **** going on, that's not in the cards right now.
 

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A little hard starting on a cold day isn't unusual. Heck, given a week of cold days my Daytona won't start at all (battery at end of its life).

Anything short of a major crash isn't going to affect the engine internals. I've bought dozens of crashed bikes and never had an engine issue. They're very robust and you'd see major frame or fork damage before anything affected the motor.

If the compression test was done right and all cylinders are reading low it can only be a fuel washing issue (too much fuel being sprayed into all the cylinders resulting in the oil being washed off the walls and thereby evenly wearing all the cylinder walls to the point that they lose compression evenly over time). I've never experienced that but would think you'd feel it while riding; that the bike just wouldn't be as responsive, but I don't know. I suppose if you had a fuel controller with the wrong map for your bike it could cause this.

I know people hate on track bikes but I've been around a lot of racers and they all baby their track bikes. They have a lot of money into them and give them a lot of love. Sure they may see higher revs than street bikes but it's what they are designed for and even at redline are running well within tolerances. And mileage is of course super low usually. If your bike had been mistreated badly you'd have noticed it well before your current 47k miles.

Assuming the compression test is accurate, to me the best course of action is to swap out the motor. I've had only good experiences with the salvagers on eBay. On expensive things it's best to contact them directly and see if they have a web store or are selling locally. That way they avoid the eBay fees and are more likely to deal on the price. And you avoid paying sales tax.

For around $1k this is the one I'd buy if I were buying today:

 

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Discussion Starter · #5 ·
A little hard starting on a cold day isn't unusual. Heck, given a week of cold days my Daytona won't start at all (battery at end of its life).
<snip>
If the compression test was done right and all cylinders are reading low it can only be a fuel washing issue (too much fuel being sprayed into all the cylinders resulting in the oil being washed off the walls and thereby evenly wearing all the cylinder walls to the point that they lose compression evenly over time). I've never experienced that but would think you'd feel it while riding; that the bike just wouldn't be as responsive, but I don't know. I suppose if you had a fuel controller with the wrong map for your bike it could cause this.
<snip

Assuming the compression test is accurate, to me the best course of action is to swap out the motor. I've had only good experiences with the salvagers on eBay. On expensive things it's best to contact them directly and see if they have a web store or are selling locally. That way they avoid the eBay fees and are more likely to deal on the price. And you avoid paying sales tax.
I haven't made any modifications to the fuel delivery system, I haven't replaced the exhaust manifold or air filter (except with an OEM filter), so if fuel washing was a problem, that should be a vacuum leak, or something happening at the ECU, yeah? One faulty injector seems reasonable, but one injector on each cylinder delivering too much fuel doesn't. If the ECU was flashed for a full exhaust system, and then a stock system was installed without the ECU being reflashed, that could cause issues. But that seems unlikely, unless the bike was previously set up as a race/track bike, and then all the track parts--or the exhaust, at least--stripped off and the stock parts reinstalled. ...Just before it was stolen and recovered. That seems like an unlikely chain of events. IF fuel washing caused the rings to fail, and resulted in the failed compression and leak down tests, a vacuum leak making the ECU think the bike is running lean seems most probable.

I guess I'll have to wait for a better answer until the engine has been dropped and the head removed.

Unfortunately $1100 isn't in my budget, not after the current labor charges. I have to pay the labor I've incurred to this point no matter what, so I'll at least go until there's a good answer as to why there's no compression.
 

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If you try to start the bike a bunch without it firing you can wash the cylinders down with fuel and the won’t build compression. A way you can test test is put a small squirt of oil down each cylinder and see if compression comes back; it’s not common for this to happen but not uncommon.

If your mechanic doesn’t know enough to try this, find a new mechanic immediately. To me it sounds like the mechanic is grasping at straws if he’s sure after replacing an entire wiring harness that you suddenly have no compression so I’d be suspect of their work anyway.

Your call, but I’d take it elsewhere for a second diagnosis.
 

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Discussion Starter · #8 ·
He added oil to the cylinders, and re-checked. Pressure was blowing out of the intake valves. So, at this moment, it sounds like I'm going to need a new-to-me cylinder head assembly (head, valves, camshafts), because if 3/4 cylinders have bad intake valves, then it's likely going to cost more to replace valves and regrind valve seats than it will to replace the head. That said, if the intake valves/valve seats are gone, then IDK why, and it does make me wonder if the piston heads and cylinder walls are damaged. If it's in-time, and the valve clearance is good, then the only thing that makes sense is that something got inside of the cylinders that shouldn't be there, which could also damage the cylinders.
 

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2012, 47,000 miles. Stock except the fairings, lights, and slip-on.

I started my bike up on a cold morning and rode to work. It started a tiny bit harder than normal, but I assumed that it's because it was cold (about 40F). It seemed to ride fine; there was no unexpected noise, no apparent loss of power. When I was about to head home, I found a nail in my tire, and had to get a ride home. I brought in a pump the next day so I could get to the shop, and my bike wouldn't start. It seemed to be turning over, but not catching. I check the obvious things--neutral switch, kickstand sensor, clutch sensor--but it wouldn't start. It stayed at my workplace for about a week until I was able to get a truck to take it the mechanic.

The mechanic found that the wiring harness had been chewed through. So, new harness. When he tried to start it, he was getting spark, but it wouldn't catch. It failed a compression test--all cylinders were below 100 psi--and the only cylinder that was marginal on the leak down test was the 1st. I believe he said it was the intake valves. He said that the timing was good, and that the cam chain hadn't jumped, and that the valve clearances were good. His best guess without dropping the engine is that that the valve seats are bad.

It was overfull on oil; I'd been getting a low reading, had added oil, then been getting a high reading, and hadn't drained oil out yet. I'm assuming--perhaps falsely--that the engine didn't seize due to oil frothing and low oil pressure cause by overfilling, because it does seem to be turning over. I've been getting timing chain noise, and have an APE tensioner, but haven't installed it yet because I'm currently replacing the engine in my car. (...Which failed due to the timing chain.)

There's no evidence that the head gasket blew; there's no coolant where it doesn't belong, and engine temp has been consistent. If the head is cracked, I have no idea how, since I haven't crashed or dropped it. There are no error lights on the display.

So, several questions:

First, WHY? It seemed to run normally, and then very suddenly it didn't. If the timing chain had jumped when trying to start, I'd completely get it; the pistons would have collided with the valves, scored the cylinder walls, and I'd need a new engine. But that shouldn't be the case if it's in time. Instead, it seems like the compression went from good enough to start and run in a way that seemed normal to no compression at all overnight.

Second, are there other possibilities for the failure? If so, what?

Finally, I'm reasonably mechanically adept, but I am fairly poor, and crap at diagnosis. I'm already at about $400 in labor, and it sounds like I'll be at about $1100 by the time this is done if I have the mechanic do it. I'm k-swapping engines on a Civic, and I've done all my own mechanical work on my bike up to this point, but I've never completely disassembled a head or block. Is it a good idea or a bad idea to try and do this myself, if this is, in fact, just a valve seat regrind on the head? (I assume that I should plan on buying new intake valves as well.)
Overall compression figure readings aren't that important as gauges differ.......What IS important is the variation in the readings between cylinders..As long as they're even you probably don't have a problem. You can generally hear if the motor has compression by spinning it over. I think your problem lies elsewhere judging by your description as compression doesn't just disappear unless you've had a catastrophic engine failure. Check the spark and fuel pump operation, fuses etc.....and kill that effing rat!
 

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As soon as the oil pressure got out of range your oil pressure light would turn on. They're fairly sensitive.

No start condition for you seemed to be the munched harness. Some rodent may have lunched it while parked.

I'd be tempted to get a second compression check somewhere else 'cause this ain't makin' sense. From fine to all low with no symptoms just ain't likely.

But if it is what you're saying I'd pony up the $1k or so and just buy a motor. You can do the swap yourself and given how high mileage yours is it's not just a repair, it's an upgrade.
These engines will last way more miles than what this one has done as long as they're looked after. I ride with a guy that had one that had done over 145,000km (90,000 miles) and still ran sweet. He only sold it because he bought a Fireblade 1000RR.
 

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He added oil to the cylinders, and re-checked. Pressure was blowing out of the intake valves. So, at this moment, it sounds like I'm going to need a new-to-me cylinder head assembly (head, valves, camshafts), because if 3/4 cylinders have bad intake valves, then it's likely going to cost more to replace valves and regrind valve seats than it will to replace the head. That said, if the intake valves/valve seats are gone, then IDK why, and it does make me wonder if the piston heads and cylinder walls are damaged. If it's in-time, and the valve clearance is good, then the only thing that makes sense is that something got inside of the cylinders that shouldn't be there, which could also damage the cylinders.

You said above that your mechanic has confirmed the valve timing is okay. I agree that none of this makes sense, but if your timing is okay and your clearances are okay then the next thing to do is pull the head and figure out what's going on.

I agree that none of this adds up. But if the intake valves are really leaking then you might as well pull it and figure out what's up. There is really no other course of action at this point, assuming all this is true.
 
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