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Super Moderator "Loose Nut"
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Sounds valve area. The sound is a solid hit, like valve slapping close. I would double check valve adjustment. Then a compression test. Sounds one tap per engine revolution is why I think it's valve related. Could be stuck valve. Good luck and keep us informed.
 

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Discussion Starter #4 (Edited)
Sounds valve area. The sound is a solid hit, like valve slapping close. I would double check valve adjustment. Then a compression test. Sounds one tap per engine revolution is why I think it's valve related. Could be stuck valve. Good luck and keep us informed.


I agree... it is one tap per revolution.
I double checked valves ... it’s not there
When you are close to it it sounds exactly as if the sound coming from where the cylinder is attached to the bottom end...
It makes me think it’s part 12 or 16 in this picture
 

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was it making the sound when you got the bike?

I went to see a 650 with only a few thousand miles on it this summer, the owner said it had a 'clicking' noise in the front cylinder.

Long story short, he drove it home about 30 miles on the highway with no oil in the crankcase. It had an oil leak and he wasnt keeping up with it - it started tapping 30 miles away, and he just drove it. The next day he drained the oil and only a half a quart came out.

If the bike has been oil starved then all the bearings are questionable, including the transmission.

I told the guy not to bother starting the bike, I heard all I needed to know from what he told me.

Do you have any info on the bike?

It could also be a bent valve. When you check the clearance did they need adjusting at all? I would expect a bent valve would not close all the way, therefor the clearance would be well out of spec (sloppy loose).

If the bike was being run near red line, in 4th gear for example, and was then shifted down to 3rd it would mechanically red line the engine, and the first thing to fail is usually the valves cannot get retracted by the springs fast enough, and the piston hits the valves. Since they are at an angle to the piston, they get bent.

Like Les said, a compression test will tell you if you have a bent valve. It wont seat correctly and the compression will be low.

A bent valve is easier to fix than a bike that was oil starved and spun one or more bearings.
 

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Discussion Starter #6
was it making the sound when you got the bike?



Do you have any info on the bike?
You are hitting it right in the head !
I picked up the bike last night .
Similar history as yours
Guy said he was riding and a nick clunk came up and engine died.
Started it again a drove it 2 miles and sound was bad so he called a tow truck.
Towed to same mechanic he used for oil changes etc.
Bike has 12k miles.. flawless looking bike.
Mechanic told him it was a Rod nock and quoted $2K plus parts to fix.

Today I adjusted the valves and check compression... 165psi in both cylinders.
Checked the oil and had only 22oz in there that’s like 1/4 of what it should have. So, it was definitely oil starved.

I’m planning to order an engine from eBay and swap it. Have done it many times before.
- - - - - - - - - -
I just heard back from previews owner - he is livid because he paid that mechanic for an oil change 40 miles before the big clunk.
He can’t believe it there was no oil ...
He even has receipts
 

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I agree... it is one tap per revolution.
I double checked valves ... it’s not there
When you are close to it it sounds exactly as if the sound coming from where the cylinder is attached to the bottom end...
It makes me think it’s part 12 or 16 in this picture
A rod bearing knock is normally a deeper sound, like tapping a hammer on a solid metal. Take a stethoscope and determine exactly where the noise it coming from. Another area to check would be timing chain tensioner area. I've heard simular sounds from timing chain master link with loose side plate hitting engine case.
 

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That does not sound like a rod bearing, they make a definate knock sound . That is more of a tick tick, which would indicate valve, rocker arm, cam bearing ,cam chain sort of thing from the top end.
No stethoscope handy,, then use a screwdriver handle pressed to your ear.
 

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the 22 ounces of oil is a possible cause of engine failure. Its suppose to have 4 quarts, and that is just 0.68 quarts.

The only other question: is the bike leaking oil now, did something go thru the crankcase and leak out almost 3 quarts of oil, then it stopped when it reached the bottom of the damage to the case?

If you have already decided to replace the engine its a mute point for you, but the previous owner: yes I would be upset if the guy got distracted while changing the oil and only put 1 quart in the engine.

Its also possible the previous owner dropped the bike and damaged the crankcase, hit something and cracked it open, or he red-lined the engine by down shifting at hi rpms, someone else borrowed the bike and messed it up...

but it all comes back to the oil level - if you cant find any reason why the oil leaked out down to one quart, then that was the cause of the engine failure.

I see Vstar 650 bikes for sale with less than 10k miles on them for less than $1500, sometimes less than $1k. People park them for a couple years, the carbs are full of goo, the tires are dry rotted, the battery is dead and the tank is full of rust, but as long as the engine was in good shape when the bike was parked you can put your carbs on the engine and it should run perfectly.

The only thing you have to watch for: in the early 2000's the bike got a cat converter added to the exhaust, and I think a throttle position sensor added to the carbs - so the carbs, ECU and the exhaust are different across one model year boundary. I dont remember which year exactly. Other than that all the 650 engines are the same. I think if you just change the block and heads out, and keep the carbs and intake and exhaust and ECU from your bike you should be good.
 

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BTW, this is one reason why I do as much mechanical work on all my vehicles as I can. All it takes is for a mechanic to make a simple mistake, and your engine is destroyed. Whether or not you can get someone else to replace your engine because they screwed up an oil change is questionable.

And if they did own-up to the mistake, do you want that guy replacing your engine?

I sleep better at night doing my own wrenching on my bikes and cars.
 

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Discussion Starter #11
I sleep better at night doing my own wrenching on my bikes and cars.

Isn’t that the truth !
I never ever let anyone touch my bikes ... and when I get a bike even if everything is good and has service records... I reset everything do valve,oil, brakes etc etc so I know what I have going on at all times



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A motorcycle is different from a car - a motorbike has to be 100% all the time, or you stand a good chance a serious accident.

If your engine bogs while you are pulling out into traffic, its not a dented door panel...

let us know how this works out for you, if you get a drop in engine replacement.
 

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Discussion Starter #13
A motorcycle is different from a car - a motorbike has to be 100% all the time, or you stand a good chance a serious accident.



If your engine bogs while you are pulling out into traffic, its not a dented door panel...



let us know how this works out for you, if you get a drop in engine replacement.


I’ll get to check a couple more things tomorrow as per you guys’ advice.
I also just found a guy selling a full bike for parts with a running engine about 2 hours from me ... it’s a much better deal than he ones i can get on eBay... well, same price but I’ll have loads of parts for future projects


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Driving in this morning (in 3 inches of snow) I realized: the previous owner cannot blame the mechanic for not putting the proper amount of oil in his bike, and the engine being oil starved as a result.

Because a motorcycle normally has no low oil pressure or low oil level light, you HAVE TO check your oil level every morning before you start the bike. Its 100% on the rider to TCLOCK inspect your ride before you start it up every day, for all the reasons we already discussed.

It only takes a moment to reach down with a small mirror and check the oil level in a 650 (and most Vstar bikes) with the nice little sight-glass on the side of the engine case.

So I have to say for the previous owner: mechanic made a mistake, but the owner wrecked the engine.

There are several ways a MC engine can lose all its oil, and you wont always see a 3 quart puddle under the bike when it happens.
 

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.....I’ll have loads of parts for future projects

...
Dibs on the mirrors! :^)

I just got my Royal Star in september, the original owner took off the stock mirrors an put smaller aftermarket mirrors on the bike that have a wavy & wide angle view of whats behind you.

The first rule of modding a bike is the stuff you put on it should be at least AS GOOD as the factory parts.
 

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Discussion Starter #16
I agree on your mods rule ! I hate when I see bikes modified with low quality parts.
Couldn’t pick up the parts bike before heading out of town for the holiday
Hopefully it will be there when back


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Had the exact same sound from my Vstar 650 this summer. Turns out it had an oil leak that on a long road trip eventually starved the front cylinder of oil. Took the engine out and the heads off, turns out to be the plane bearings for the front cylinder. Now in the process of splitting it. Hopefully the crank isnt scored or the rods out of spec. Theyre pretty pricy!
 

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whats a plane bearing?

sometimes you get lucky, if the oil pump starts sucking air or froth its the cam bearings in the top of the engine that get oil starved first, or if you get gas in the oil and it gets really thin, it can supply oil to the main bearings on the crank, but does not have enough pressure to reach the cams.

but usually by the time you hear something knocking, all your bearings are gone, including the transmission

with no oil pressure zero warning light on most of these bikes, you really do have to check the level every morning. Thats why they made it so easy with the sight glass - just need a little mirror on your keychain.
 

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It only takes a moment to reach down with a small mirror and check the oil level in a 650 (and most Vstar bikes) with the nice little sight-glass on the side of the engine case.
I thought that sight check for oil level on the 650 was so cool. The coolest thing on the bike. Was a little disappointed that the 950 didn't have it.

Also correct that it might be the mechanic's fault, but the owner should have double checked the oil level. Underfill, overfill, no drain plug, forgot to screw the fill plug/dipstick back in, ... there's no end of ways to screw up something simple.

Example, years ago after a well known oil change place changed oil in my truck I found a wrench lying on my battery this frickin' close to shorting hot terminal to body. That would have been interesting as it bounced around. I want to see new oil at the right level. And that I have a dipstick and a fill cap, .... I get inspections and oil changes on family cars at one place. He seems happy that I double check his people.
 

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From several bad experiences having someone else change the oil in my vehicles, the one thing I always do is change my own oil and filter.

To say if backwards, if you want to destroy an engine, mess up the oil. It only takes a few miles to completely destroy an engine with no oil.
 
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