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Discussion Starter #1 (Edited)
Bike was running perfectly for last 11k. No issues smooth and relatively quiet 馃檪
Then I decided to change oil little different way. The one I use is Rotella 5-40. This time however I did not warm the engine before oil drain. I just open the drain thing (as you know it is not exactly a bolt) and just left it drain for a week. After adding a gallon of oil and new k&m filter I started the bike. It is running very nice up to about 3000rpm, then starts to knock like it will have broken pushrod, or half engaged gear. I am afraid to get it to that level. But as far as riding under 3000 is perfect as it was before. I do not believe this is chain tensioners. It is way too sudden. Any ideas?
 

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I'm definitely not the guy you're looking for on this forum. I'm a newb. But why would it matter about running the engine? I just changed my oil 2 days ago and I followed an oil change procedure described on this site. It said nothing about running the engine first. It started with "place the pan under the drain plug". Did I follow the wrong procedure? I'd imagine someone would have said, "Hey, don't forget to run the engine first" if there was a danger of damaging the engine.

So my question is, why would not running the engine first cause engine damage?

Also, is there another thread describing the oil change procedure that explains all of that? Do I need to change my oil again?
 

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Running the engine a smidge before draining is to warm the oil up so it will flow easier, that's all.
 
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Ditto on what Roadpouring said. Overfilling can cause issues. Double-check your sight glass. There should be an air bubble at the top after you've given the oil time to all settle back into the pan.
 

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Over filled or maybe go up to midgrade or premium gas and see if the knocking stops.
 

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I'm wondering if maybe the hydraulic tensioners might "drain down" if the bike sits long enough? I do know the engines in these bikes make enough noises to drive you crazy if you let them.

I had some very serious concerns after I did the tuxedo mod last year. I started the bike up and there seemed to be a loud knock. I let it idle for a while, and it seemed to get only marginally better. I was worried that I'd messed up the mod and maybe the stator was causing the noises. I pulled it back apart and looked it over, and it didn't look like anything was going on that would be making the noise that I was hearing.

I ran it that way, and it got noticeably better. Ended up going to MCCTs anyway. . . .

It's a noisy engine.

GDI
 

FREEBIRDS MC CENTRAL NY
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WAYYYYYYYYYYYYYYYYYYYYY to much oil. Drain it down to the point where others said to, and then try to see if the knock goes away

Sent from my A502DL using Tapatalk
 

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First things first. Unless you live at the north pole, you should be using 20w50 oil. 5w40 is to thin to provide protection for the bearings under load. It has a very low film strength compared to a heavier oil. I can't remember exactly how much oil I put in my Vulcan 750, but it seems it was very close to 4 qts. On the centerstand, you should fill it up VERY SLOWLY until it just touches the top of the sight glass (not the line cast into the case next to the sight glass) If you think you have too much oil in it, siphon out some until you see a tiny little bubble at the top of the sight glass, and leave it there. You will notice that when the engine is running there is no oil visible in the sight glass. That's because the sump is mostly empty, the oil is circulating throughout the engine. What happens when you put too much oil in an engine is the crankshaft will hit the oil in the sump. The engine will feel sluggish and very low on power. And it will blow oil out the breather. The first thing I would do is drain that 5w40 out of it, and fill it to the proper level with 20w50 oil and see what happens. If there is still a problem, it is not likely oil related. Also I always use Emgo oil filters on the VN750. I won't use anything that says K&N or Fram on it, though I don't know if there is a problem with K&N oil filters or not. Fram oil filters are junk.
 

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I have to ask why you run such a heavy weight oil? I do think 5w40 is too light. Book states 10w40. I've always kept with the suggested weight and never have had issues. I do see you're in Arizona so maybe it's the hotter temps there. As for K&N, I've not had issues with their filters.
 

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It gets super hot in AZ. 118 degrees is not uncommon during the summer. And it never gets below freezing where I live. The oil fill cap says 10w40. But if you look in the owners manual (I don't know where mine is at the moment) there is a temperature chart in there that shows which oils can be used in what temperature ranges, and it shows 20w50 covers the widest range of temperatures, far below anything I would think anyone would be riding in. I use it because it provides better protection for the engine. It has a higher film strength than lighter oils so it is less likely to break down and allow metal to metal contact. Also, because it is thicker, it stays on vertical surfaces longer than a thinner oil. I have put 190,000 miles on two Vulcan 750s, and never had a problem with it. I have owned more than 50 bikes total, and used it in every one of them. Again no problems. It's the only weight oil Harley Davidson recommends. You also need to be careful using lightweight oils because some of them are Energy Conserving, and can damage a wet clutch. While it does not specifically say so, the main reason all manufacturers recommend the lightest oil they think they can get away with is to save a mile or two per gallon in gas mileage, rather than make the engine last longer. You can thank the EPA for that.

As for the filters, K&N OIL filters may be fine. K&N air filters are crap. They are marketed as a "high flow" filter, and because they flow more air, they also flow more dirt. They also lean out the air/fuel mixture, which is already too lean on a stock engine from the factory. You can rejet to compensate for that, but if you are looking for more power, you won't get any noticeable power increase out of it. I prefer a reliable long lived engine. You can also blame the EPA for the too lean jetting.

As for Fram oil filters, I personally know of two car engines that were destroyed by them. The element came unglued from the can and plugged up the oil passages. Watch this video about oil filters. You'll see what I mean
There are plenty more videos like it.
 

FREEBIRDS MC CENTRAL NY
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Most people have found that their Vulcans DO NOT LIKE 20/50. Shifting and clutch issues,rough running, etc.etc.etc.A lot of us run Rotella 15/w40. What we really need is another oil discussion.lol

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I figured maybe 5w40 was a typo for 15w40. Rotella, of course.

Had a father-in-law that insisted you had to wait five minutes to read a dipstick, to allow the oil to collect on the stick. :doh:

He also placed a level on the engine before checking oil. He knew which car needed plywood under a tire.

He would probably let one drain for week, if you let him.

He bought a brand new car, a 5spd. 2nd and 4th gears were never used. 1-3-5 every time. And if you drove it, you damn well better not screw up his gas mileage by using 2nd and 4th!
 

FREEBIRDS MC CENTRAL NY
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What's that? We need another oil thread? I'll go start one right away!
How about two?

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On page 62 of the owners manual, it says the following oils can be used:
10w40
10w50
20w40
20w50

Oil capacity is 4.2 qts. when changing the filter.
 

FREEBIRDS MC CENTRAL NY
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On page 62 of the owners manual, it says the following oils can be used:

10w40

10w50

20w40

20w50



Oil capacity is 4.2 qts. when changing the filter.
Yes and every motor is different. Some have had good luck with 20w50, yourself included. But the majority seem to like 10w40, as I've seen from posts on here. It all depends on break in, usage over time, and what oil is consistently used. If the bike has been ridden for 40,000 miles on 10w40, most likely it won't like 20w50, and vice versa.

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Discussion Starter #18
Well... that was not a typo. I guess for last 13 years I was riding on this $20 per gallon oil: Rotella T6 5W40. Why did I ever do that? Read somewhere that this will be excellent. Anyhow, whats done is done. What am I up to now? I like the bike was great to me for all those years. Never found a spec of metal on the filter. Changed oil once per year regularly. Used K&M filters. Guys, what shall I do now?
 

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Yeah, I'm running 5W40 Shell Rotella Synthetic, too. Seems to be OK. . . .

The only thing that I notice is that the clutch *really* grabs when the motor is cold? I'm thinking that maybe I should try another oil on the next change to see if that makes any difference.

You all think the 5W40 might be causing the clutch to be grabby like that? Maybe the oil doesn't really matter?

GDI
 

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15w40 would be ok unless it is really hot. The older an engine gets, the more wear it has, and the looser the clearances are, such as the crank bearings and the con rod big end bearings. You need a thicker oil for a high mileage engine to help fill in those looser clearances. But weight of the oil did not cause this problem. Neither did overfilling, especially if you changed the filter. I've always just poured a gallon in mine, and it comes out perfect, with just a tiny bubble at the top of the sight glass. All VN750 engines are built exactly the same. Some (probably most) have been modified to some extent, but nothing that would change oil capacity. This is something else.

I remember when I had a Kawasaki EX500, and belonged to the EX500 forum. There were a couple of cases where the bike was dropped, then picked up, started, and ridden away. Shortly thereafter the engines seized up from lack of oil pressure. Apparently while the bike was on it's side, the oil pump lost prime, and did not start pumping again right away. You didn't say anything about dropping your bike, but you did leave the drain plug out for a week. Did the OIL light go out as soon as you started it after changing the oil? Also, the Vulcan 750 has hydraulic lifters. Maybe yours are leaking. But I've let mine sit for as much as 2 weeks (with oil in it) and never had a problem. That sounds more like a clanging sound rather that a bearing knock or a cam chain rattle. You also said it did not make a noise at low RPM. Cam chains and bad bearings will both make noise at idle.
 
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