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Discussion Starter · #1 ·
Today I was riding on the freeway to the dealership to get oil as I'm going 80mph the bike slowed down but my hand didn't move from the throttle. I didn't pay any mind to it , got my oil then went home and now the bike has a knock coming from the engine. I don't know what it could be but I took it back to the dealership and left it there..

The bike didn't want to start when I was trying to take it to the dealership but then after 3rd try it turned on. I got the relay fixed
2 months ago..please help. Thanks








Sorry for my run on sentence.
 

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as its at the dealership now, any hints here could be superfluous..
helps to give details,, such as what actually happens
instead of just 'doesnt want to start' etc..

also 'slowed down without moving throttle'
or 'now the bike has a knock coming from the engine'..
a 'knock' could be many things, including potentially
disastrous pre-ignition..

just basic descriptions, as if describing something
to a blindman, are generally most helpful
and may spark memories of others'
experiences, thus perhaps solutions etc..
 

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Hard to say, but it does sound a bit like either overheating and/or oil starvation. Why were you going to buy oil? Was it low?
 

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From my understanding, usually an engine would be pinging first.
Pinging results in a slight ring in the engine when revving it with or even without load.
The engine will run lots hotter, and seems to lose power.
MPG values can be as much as 20MPG lower than target.

Knocking usually only happens when the engine is seriously lugging.
Meaning, when you'd be going at 1400RPM full throttle in 5th gear or so. The engine will no longer give a smooth acceleration, start and slow down abruptly when trying to accelerate; this usually only happens when accelerating at very low RPMs.

At the RPM range you mention, it's really hard to knock the engine, or even lug it.
At 6-8k RPM these engines are rock solid, and almost can tow an elephant!
What's closer to a possibility, I think, could be that there's a problem with either the air intake (air filter), or a little grain of sand or rust in the fuel injection system clogging it.

If the 'knocking' you experience is a knocking sound instead of an engine feeling or acceleration issue, there might be something wrong with the valves.

Can't think of anything else, other than catastrophic engine failure ;)
 

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At the RPM range you mention, it's really hard to knock the engine, or even lug it.
At 6-8k RPM these engines are rock solid, and almost can tow an elephant!
What's closer to a possibility, I think, could be that there's a problem with either the air intake (air filter), or a little grain of sand or rust in the fuel injection system clogging it.
Your always good for a chuckle mate :laugh::D
 

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Well my engine piston blew up on my bike
Last we heard, you took it back to the dealer to have it checked out... what did they say, or should I say what did they do when they had your bike in the shop?
 

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Discussion Starter · #8 ·
From the start they kept saying I could have put the oil filter incorrectly but when they checked it was on right. They end up checking the valves but that was fine (doesn't need to be checked until 12kmiles). The bike didn't look like it had oil starvation. So they went ahead and took pictures of the piston to send it off to Honda




Sorry for my writing
 

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You said in your OP that you were on your way to buy oil. Why? Was the bike using noticeable amounts of oil between changes? If so, how much?

Was the cooling system operating correctly? Was it low on coolant, or the radiator clogged with dirt? A seized piston can result from overheating.

How many miles had it done, and how many oil changes has it had? What sort of oil did you use?

Did you experience any other problems in the days before, such as taking longer to start?

What kind of fuel were you putting in it? Always the same type?

In your position, I would want to know exactly what has happened here, because the damage might not be limited to just the piston. When a piston gets so hot that it seizes or breaks, that can be the last act in a whole series of bad stuff going on. For instance, lack of oil on the piston and bore might mean lack of oil everywhere - the piston was just the first thing to give up.

It could also be the result of 'pre-ignition' or 'pinging'. This can result from a mechanical issue elsewhere in the engine, or bad fuel. For this to get bad enough to cause major overheating of the piston though, it is highly likely that you would have heard and/or felt it for some time beforehand. It usually sounds like a rattle or knocking under acceleration, and a small loss of power. The power loss you mention just before the knocking started doesn't sound like pre-ignition though; more likely that was the piston starting to grab the bore.

It could also be that you simply suffered bad luck in the form of a faulty piston ring. This can happen, though it's rare. Whatever the cause though, you need to know the full extent of the damage, especially to bearings and cylinder bore.
 
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Discussion Starter · #10 ·
You said in your OP that you were on your way to buy oil. Why? Was the bike using noticeable amounts of oil between changes? If so, how much?

Was the cooling system operating correctly? Was it low on coolant, or the radiator clogged with dirt? A seized piston can result from overheating.

How many miles had it done, and how many oil changes has it had? What sort of oil did you use?

Did you experience any other problems in the days before, such as taking longer to start?

What kind of fuel were you putting in it? Always the same type?

In your position, I would want to know exactly what has happened here, because the damage might not be limited to just the piston. When a piston gets so hot that it seizes or breaks, that can be the last act in a whole series of bad stuff going on. For instance, lack of oil on the piston and bore might mean lack of oil everywhere - the piston was just the first thing to give up.

It could also be the result of 'pre-ignition' or 'pinging'. This can result from a mechanical issue elsewhere in the engine, or bad fuel. For this to get bad enough to cause major overheating of the piston though, it is highly likely that you would have heard and/or felt it for some time beforehand. It usually sounds like a rattle or knocking under acceleration, and a small loss of power. The power loss you mention just before the knocking started doesn't sound like pre-ignition though; more likely that was the piston starting to grab the bore.

It could also be that you simply suffered bad luck in the form of a faulty piston ring. This can happen, though it's rare. Whatever the cause though, you need to know the full extent of the damage, especially to bearings and cylinder bore.


The engine started knocking so I thought if I did a oil change on it then it will go away (this is my first bike so I don't know anything about bikes)

The coolant and liquids seem fine to me

The bike has 3200 miles. I used Mobil 1 and a Honda oil filter. I've done 1 oil change at 600 miles and then this 1 at 3200 miles

Just the day before the bike was knocking. I always noticed little power from the bike, I used to go 97 and not to long ago I couldn't get it past 88 mph. I've changed my sprocket to a 15t so I don't if they could be the reason why.

I put 93oct gas in there all time
 

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The engine started knocking so I thought if I did a oil change on it then it will go away (this is my first bike so I don't know anything about bikes) ....Just the day before the bike was knocking. I always noticed little power from the bike, I used to go 97 and not to long ago I couldn't get it past 88 mph. I've changed my sprocket to a 15t so I don't if they could be the reason why.....
Big mistake. You should have parked it when you first heard the knocking. Ah well, what's done is done.

The 15T sprocket would lower the rpm for a given road speed. This helps reduce engine wear, but could lead to a rider 'lugging' the engine at low speed - making the engine struggle to catch up, so to speak. If you whack the throttle open at very low speed on a regular basis, I believe this can lead to damage in various ways, including cracked piston rings or the piston itself, because it causes the pre-ignition I mentioned earlier. Basically, the fuel goes 'bang' too early, giving the piston a hefty whack while it's still on the way up. The rattle I mentioned is that shock travelling through the various moving parts in the engine.

Having said that, I'm not sure that modern engines, with their sophisticated engine management systems, suffer pre-ignition any more, even when going very slow. I shall give it a try next time I take a ride (doing it once and briefly won't do any harm).
 

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Discussion Starter · #12 ·
The engine started knocking so I thought if I did a oil change on it then it will go away (this is my first bike so I don't know anything about bikes) ....Just the day before the bike was knocking. I always noticed little power from the bike, I used to go 97 and not to long ago I couldn't get it past 88 mph. I've changed my sprocket to a 15t so I don't if they could be the reason why.....
Big mistake. You should have parked it when you first heard the knocking. Ah well, what's done is done.

The 15T sprocket would lower the rpm for a given road speed. This helps reduce engine wear, but could lead to a rider 'lugging' the engine at low speed - making the engine struggle to catch up, so to speak. If you whack the throttle open at very low speed on a regular basis, I believe this can lead to damage in various ways, including cracked piston rings or the piston itself, because it causes the pre-ignition I mentioned earlier. Basically, the fuel goes 'bang' too early, giving the piston a hefty whack while it's still on the way up. The rattle I mentioned is that shock travelling through the various moving parts in the engine.

Having said that, I'm not sure that modern engines, with their sophisticated engine management systems, suffer pre-ignition any more, even when going very slow. I shall give it a try next time I take a ride (doing it once and briefly won't do any harm).


Could the sprocket void the warranty?

I haven't told them that I changed it to aftermarket. I've only had it on the bike for 2 weeks
 

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Could the sprocket void the warranty?

I haven't told them that I changed it to aftermarket. I've only had it on the bike for 2 weeks
I don't know for sure, but my guess would be yes. It would come down to whether Honda want to play hard ball and play by the letter of the law.

I would simply wait for the dealer to diagnose the problem. If it turns out to be a faulty piston, a blocked oilway or something else, you're in the clear. Basically, I would leave it to them to figure it out. Telling them about the sprocket might lead to them just assuming that was the cause, rather than properly investigating it.

The worst-case scenario would be them saying they couldn't find anything wrong other than the busted piston. That would make me nervous.

Oh, and make sure to ask them if they checked for damage elsewhere, especially the cylinder. Also make sure that they flushed the engine lube system, changed the oil and replaced the filter. There's a good chance that the piston shed particles of metal when it failed and these might be lurking inside the engine. Any half-decent workshop would do this as a matter of course, but..........
 

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Discussion Starter · #14 ·
So don't say anything about the sprocket? Hopefully the warranty comes through, if not then I can see myself paying about $1k ????
 

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I wouldn't volunteer the information, no. If, on the other hand, they ask if you have modified the bike in any way, they you have to fess up.

They are the experts; let them tell YOU what the problem was.

I have no idea what the repair bill could be.
 

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Discussion Starter · #16 ·
I wouldn't volunteer the information, no. If, on the other hand, they ask if you have modified the bike in any way, they you have to fess up.

They are the experts; let them tell YOU what the problem was.

I have no idea what the repair bill could be.

Hopefully they can't notice the 1+Tooth on the sprocket lol
 
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