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Discussion Starter #21 (Edited)
Bike was definitely hot. I wasn't aware of this being an issue with these bikes, but I had tried both of those methods and neither worked - bit of throttle as well as full choke and half choke.

I have an AGM in there, and no worries since it wasn't mentioned. But if neither of those methods worked, would those mods keep this from happening again?

I think that's what the guy was yelling to me across the parking lot, but since I had my helmet on I only got a little bit of what he was saying until I took it off. Is the vacuum one of the lines that comes off of the petcock?

And would this additional issue have any tie in to the noise I'd been hearing? And I just thought of something else. I feel like I went through this last tank of gas very quickly, so would issues with the petcock cause these problems?
 

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Petcock vacuum is the center port of the petcock, the hose runs to the side of the carb, it's the easiest hose to reach on that side. If it leaks through that hose, it can drain gas into cylinder even if parked with petcock turned off.

Maybe it is flooding then. Flooding wouldn't make that noise, except, did you use the scope on the petcock? Somebody here did say their petcock was making a racket, really loud if that's what it is.
 

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Discussion Starter #24
Ok I finally got a better day to scope this out again. My findings:

Ear on the gas tank without the scope yields no noises. When I use the scope I get a muted knocking noise that sounds like its coming from elsewhere in the actual engine.

The petcock with the scope is kind of a knocking noise, but doesn't sound like it is the source of the noise.

The upper jug is a metallic clanking noise, which I guess would be the chain clanking around. I hear the same noise at the very top of the jug, the lower jug, and the very bottom of the engine, but I don't hear the ticking noise anywhere with the stethoscope.

I can hear the ticking noise with my ears towards the tops of the jugs.

In terms of tightening the MCCTs, there is no zone where the noise stops and the engine doesn't bog down. As in the noise - both the mystery ticking and the (I believe) cam chain clanking - keep going up until I tighten them too much.

Does this mean I need to mess around with the idle? If I can't figure out what this noise is then I will probably just sell this bike and get something else because I'm not looking to have something I need to tinker with constantly, and this noise completely kills any enjoyment I would have gotten by being out on the motorcycle in the first place because it's all I can focus on. Especially if I'm making a mountain out of a molehill and this is what the bike is supposed to sound like.
 

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Ok I finally got a better day to scope this out again. My findings:

Ear on the gas tank without the scope yields no noises. When I use the scope I get a muted knocking noise that sounds like its coming from elsewhere in the actual engine.

The petcock with the scope is kind of a knocking noise, but doesn't sound like it is the source of the noise.

The upper jug is a metallic clanking noise, which I guess would be the chain clanking around. I hear the same noise at the very top of the jug, the lower jug, and the very bottom of the engine, but I don't hear the ticking noise anywhere with the stethoscope.

I can hear the ticking noise with my ears towards the tops of the jugs.

In terms of tightening the MCCTs, there is no zone where the noise stops and the engine doesn't bog down. As in the noise - both the mystery ticking and the (I believe) cam chain clanking - keep going up until I tighten them too much.

Does this mean I need to mess around with the idle? If I can't figure out what this noise is then I will probably just sell this bike and get something else because I'm not looking to have something I need to tinker with constantly, and this noise completely kills any enjoyment I would have gotten by being out on the motorcycle in the first place because it's all I can focus on. Especially if I'm making a mountain out of a molehill and this is what the bike is supposed to sound like.
Backing it off from where the idle drops is probably right for the MCCTs, I’ve watched your clips a few times over and can’t really pinpoint what I’m hearing. But I’m not a seasoned pro like some on here. But I do know that these engines are noisy. Just taking a stab, do you know what kind of oil is in the bike? I’ve read a few times that could be the cause of a noisy engine.
 

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Discussion Starter #26
I have Yamalube 10W-40 in there right now. https://drive.google.com/file/d/1NUR-qejn3hv1t3dGc6zKEIeoEtB3XndW/view?usp=sharing

I'd actually heard something about the oil being an issue for an unrelated thing last year, where my oil pressure light kept going on. Someone on reddit had said that their bike seemed to have an issue with semi synthetic oil, but I believe I ended up just changing to Yamalube and that problem mostly cleared up. I say mostly because the oil pressure light comes on for a few seconds when I start the bike then goes back off.

I'm willing to change the oil for sure if people think it will help, but I'd also be looking for recommendations. I don't care if it's conventional or synthetic - I just want these janky engine noises to stop!
 

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I’ve had this bike since September 2018, it’s an 05. I’ve had the oil changed 3 times. First by the local guy when I had some tire work done. Bike was fine, Second time was when I had the dealership replace my dead stator. After the dealer touched it my oil light popped on when I started the bike and sometimes when I’d hit the throttle hard. I also had bouts with the coffee grinder syndrome. If you’re unfamiliar that’s when the clutch makes a terrible grinding noise. So , third and last oil change was early this year when I caught a big screw in my rear tire. Again by the local guy, oil light never came on again and the clutch is silent. I looked at my receipt and he’s got 10w 40 on there, but there’s no brand name. But I’m pretty sure they did not use the same stuff.
 

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Have you touched the 'scope onto the valve covers? Thinking maybe a lifter/lash adjuster isn't pumping up.
 

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Discussion Starter #29
Mine is also an 05. I change the oil on my motorcycles at the beginning and end of each season since I don't put enough miles on them to worry about mid season changes. I don't think I've had the coffee grinder noise since I wouldn't say this sounds like a coffee grinder but I also wasn't able to find a video of the noise either on here, just lots of references from people that know what the noise is. What exactly does that noise sound like? Grinder full of whole beans, full of grounds, empty grinder whirring?

From brief googling, I'm thinking the valve covers are the tops of the two halves of the engine? If so, yes it's just the same noise that permeates the engine, about as loud as it is on the sides and the bottom. I don't know what you mean by lift adjusters not pumping up, but how would I go about testing it to see if that's the issue?
 

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To me, coffee grinder sounds like a bad bearing on a fan motor, sort of. A cross or mix of howl, squeal, and a bit of screech. But the biggest thing is the sudden and harsh grabbing of the clutch if you're not quick to pull the lever back in.

Yes, valve covers are the two pans on top of the cylinders.

You'd have to get the valve covers off to look at the lash adjusters. Can download the free manual to get a better idea of what all this looks like.

I'll go back through this thread later when I have.more time, need a refresher on this.
 

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The coffee grinder noise happens when the oil doesn’t circulate through the clutch basket to properly “wet” the clutch plates. It usually clears up as the oil loosens and begins to flow. To me it sounds more like when the brake pads on a car are completely shot and you get that metal on metal screech sound. I think it’s safe to say if your bike did it you’d know. The friction plates are still dry and they grab right away as opposed to just feathering in like normal. Plus it’ll jolt the bike a little when dropping into 1st. First time it happened it was a “WTF was that?!” moment. Safe to say it’s not an issue you’re having from what you’ve been posting, but I can clearly tie it back to oil type in my situation.
 

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Discussion Starter #32
That sounds more intensive than what I'm willing to do myself for purely exploratory purposes, because I don't trust myself with engine innards/I don't think I have the time to learn enough about innards to do it correctly/I don't want the bike to be unrideable for the reason that it's in pieces because I haven't put it back together/I also don't have the space to be doing this as I live in an apartment and don't have the space to be doing this type of work. Is opening up the top of the engine the only way to tell if the issue you described is actually the issue?

I do think the bike grabs first in a weird way, or at least a different way than my SV650 did, but I'd chalked that up to just being a different motorcycle, but yeah it doesn't make any weird noises like what you're both describing so I guess it's good to write that off of the list of potential causes.
 

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Trust me I understand. I live in the city and only will take on what I can do outside in front of my house. Hence the reason I had to pay the dealer to do my stator replacement.

But back to your bike, if you say it grabs a little weird then try pumping the clutch lever a few times before you drop it into gear. That is the “work around” for the clutch grinding. If that makes it feel smoother I’d stand by the idea that it could simply just be the type of oil in the bike.

I’m not a mechanic, I’m inclined enough to be dangerous but I’m always going to look at the easy stuff first.
 

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Unfortunately, taking the valve covers off is the only way to look at the lash adjusters. Unless we can find something else that's making the noise.

You've taken care of the number one cause of ticking for this engine, the ACCTs. Lash adjusters or rocker arms are number two, plenty of cases where the LAs were bad or rocker arms have slipped out of place.

It's smart to understand you may not be able to complete a repair. You can weigh the cost of having it done.

I just can't think of anything else it can be. We've just about ruled out the balancer.
 

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Discussion Starter #35
What does that job entail? I assume emptying the gas tank and taking it off the frame then taking the covers off? Are there going to be fluids that will be coming out? Small pieces to go shooting all over the driveway, never to be seen again? My Clymer doesn't say anything about anything coming out, although I do get a kick out of the fact that it specifically says NOT to lose the washer and rubber grommets for the bolt holes.

Is a tear down of any sort needed to inspect those pieces?
 
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