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Discussion Starter #21
It was suggested to me to do a compression test!
 

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1983 Honda vt750 Shadow
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You are over complicating the compression testing procedure. Think of it as a normal cylinder with only 1 spark plug. Just like on your lawn mower. You only take out 1 spark plug and you test that plug hole with the tester. Then go on to the other 1 cylinder and test only 1 spark plug hole. Only one test on each. If it is low then put in about a tablespoon of ATF or engine oil to seal the rings for another test. Make sure the battery is strong or it will effect the readings. Open throttle, - 8 puffs or more.
 

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Discussion Starter #23
I'm sorry for the misunderstanding. Practically everything I've read, or video I've watched always made reference to "all" of the cylinders; they're never spoken of as "the other" cylinder, or both cylinders. So I assumed, wrongly as it turns out, that all meant all four. It is a learning experience, and one that I am extremely grateful for. I will see how high the oil brings it up in the morning.
 

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I'm sorry for the misunderstanding. Practically everything I've read, or video I've watched always made reference to "all" of the cylinders; they're never spoken of as "the other" cylinder, or both cylinders. So I assumed, wrongly as it turns out, that all meant all four. It is a learning experience, and one that I am extremely grateful for. I will see how high the oil brings it up in the morning.
You do understand that you only have two cylinders and each cylinder has 2 sparkplugs.
 

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Discussion Starter #25
Yes I understand! I hope that you understand that there are some things that I don't. Because that explains the reason that I am here (on this site).
 

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Discussion Starter #26
I have 115 psi's on the rear cylinder (135 w/oil) and 115 on the front (130 w/oil.) All I know is that this is not good...
 

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1996 Honda VT 1100C2 ACE
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Big discrepancy! I changed the valve core on the compression tester and it is now showing 110 psi's on the front cyclinder(s) and 115 on the rear two.
It has been my experience that if you replace the core with a standard tire core the compression tester will not work properly. Did you use a core designed for a compression tester?

Sent from my LGL34C using Tapatalk
 

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I didn't notice that you said you replaced the valve core. It will drastically change the reading with a tire valve.

You can go to O Reilly auto parts and "rent" a compression tester, for free most of the times, and check the readings with another tester to compare.
Don't give up till you get the correct reading.


But will the engine run at all? What is the reason for the compression diagnosis? Have you ever had it running?
 

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Discussion Starter #29
When I first got the news about the difference in valve cores I was depressed at yet another set back, and then I began to think, "what is he going to think," but maybe there's a silver lining because when I performed the test with the proper core I got much higher compression (161 psi's) unfortunately it only worked once. I live in a rural area but I've called O'Reily, advance auto, auto zone in reference to purchasing a core but they don't sell them. I may have to go online or check back with them about the chance of renting a tester. Yes, the engine runs but it doesn't sound 'right' as a matter of fact it sounds bad and lacking power. The last few times I rode, it would kill whenever I stopped, like at a red light, and I could only restart with choke. As for the reason behind the compression diagnosis: I had an oil over-fill and have been told that an over-fill can result in anything from a mess to premature engine damage. I've put in 69k miles on the bike and never had a moment's problem until then. So I wondered whether engine damage could be the source of my problems.
 

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2000 Honda Sabre VT1100C2
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Hello 750 Genie. I realize I have come late to the conversation, but, I have gone back and read every post on this bike all the way back to the "Oil overfilling". If the bike now runs, albeit poorly, you are making progress. I had a very similar problem with a Suzuki Savage. Same exact symptoms. So let me ask a few questions.
1. when you did the oil change that started all your problems, was this just a regular oil change? No other maintenance at the same time?
2. Did you eventually get around to replacing the needle and seat?
3. Are you positive you overfilled the crank at oil change time? This is important.
I believe all of your initial problems were related to the needle and seat. Please answer all 3 questions.
 

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Discussion Starter #31
Yes it was just a regular oil change and no I never did replace the needle and seat (I posed the question to the guy that was advising me and he didn't respond so I took it as if he felt it to be unnecessary) I am positive that I over-filled because at the time of the oil change I remember thinking that I required 3.5 qts but it should have been 2.5, I was fixated on 3.5 because that is how much gas I get. I've also had ppl to tell me that my problems have nothing to do with the over-fill. MY BIGGEST PROBLEM IS I DON'T KNOW WHAT THE PROBLEM IS. Meaning: I am open to suggestions and/or a course of action.
 

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Discussion Starter #32
What eventually happened with your Suzuki?
 

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On the Savage had the same exact issue you had. Oily gas leaking out of the exhaust and air filter/box. Crankcase was full of gasy oil. Did it twice before I realized the gas was just seeping by the float needle, overflowing the float bowl and running into the crank and air box. I drained the crank and put fresh oil and filter in. Pulled and cleaned my air filter and let the air box dry out. REPLACED the needle and seat and cleaned the carb while I had it out. Problem solved. I cant stress enough how important it is that the needle and seat be replaced if as you say you smelled gas coming out of your exhaust and air box and gas got into your crank. You did say you went through a tank of gas this way right. There is only one way a tank full of gas gets in the crank...worn needle and seat. If rebuilding a carb is not something you are comfortable doing have it professionally done. I really feel that will take care of most if not all of your issues.
 

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Discussion Starter #34
I have done all that you suggest except replacing the needle & seat. I've cleaned the carb twice. The issue is no longer gas coming out of the exhaust etc. now when I ride the bike tends to kill when ever I release throttle or stop. Are you saying that it is the same issue?
 

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Check the plugs and see if they keep getting black. If not the carbs are probably better now. You may have a poor fit at the carb boots and a vacuum leak may be causing your dying problem. Also have you adjusted the mixture screws out to about 2 turns?
 

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In all this confusion after the oil overfill and subsequent overflow did you replace the air filter ? and check/drain the collection tube ?
You could have done everything else right and still have a problem if the filter is saturated. I read thru a bunch of your posts , but didn't notice if you had changed or tried to clean the filter. Your symptoms could be that simple.

Just my 2 bananas .

I personally don't think you have a compression problem but yes a true reading would be a good thing at this point.

I can't help but feel like in the confusion and newness of the bike maint/repair to your world that you are somewhat over thinking the problem.

So conquer the easy stuff first. In this case it may well be something as simple as the filter. An overfill by 50+%
and then a 50 mile ride probably didn't wreck your bike , but sure pressures oil into all kinds of places it shouldn't be.

I think the idea that your problem is likely fuel related is a good start. That includes air filter and carb boots. The easiest things to check right now are (as @swifty2014 said ), make sure carb. boots are not leaking and air filter is new and clean.

If this doesn't get it running well , next go to rich/lean screw again as @swifty2014 said.

If that doesn't get it , then go back tru the carbs , floats , etc. As @09Spirit is suggesting. But each step , starting with filters and boots has to be right or the float , needle , etc won't fix anything. A boot leak is a lot of air that the carbs can't control. A plugged filter shuts you down at idle and fouls your plugs

Good luck buddy , I'm convinced it is simple but as long as you have gone this far with compression testing keep going til you have a true reading........ after that , the next time getting that reading will be a piece of cake.


You're learning and game to get it right yourself that is a good thing , only two plugs need to come out for the test --- one from each cylinder ----- You are getting there. Remember only a short time ago none of this meant anything to you.

These bike's are pretty tough. I don't think you have killed it with an oil overfill.
 

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OK when you say that you cleaned the carb twice, how did you clean it? Did you actually disassemble the carb and use carb cleaner and compressed air to clear jets and passages? If so why did you not replace the needle and seat then? The reason I feel that is so important is because if it leaked by before it will likely happen again. Look at it this way: Trouble shooting is a matter of elimination. As the other guys are saying don't over complicate it. You basically need 3 things for you bike to run: 1. Air/fuel mixture in the correct ratio hence the suggestions of a clean air filter, clean passages and jets and properly set float. 2. Good compression to pull the air/fuel mixture in and push the exhaust out hence the compression test and 3. A means to ignite the air/fuel mixture at the proper time. So what do you do with this info? As instructed, do a compression test and don't move on from that task until you are SURE you have accurate readings. If they are good readings the you can eliminate that as the problem. Then move on to air/fuel. Clean air filter, properly cleaned carb with correct float setting (if adjustable) new needle and seat and float bowl gasket if needed, carb correctly mounted to boot with no leaks making sure all hoses are tight. 3. Sounds like your ignition is ok. Lastly, while you have the carb off the bike, check to make sure the petcock is operating properly. I know it is alot of info and time to take the steps but process of elimination is the key.
 

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Discussion Starter #38
I appreciate your thread and needless to say I hope you are correct and that I am complicating matters. Nothing would please me more than to learn that it is far less serious than I am imagining. However, I have changed the filter several times. I am on my third since the initial breakdown.


There is no longer any question in my mind whatsoever in regards to the proper method of testing for compression. But the idea that all 4 spark plug holes are to be tested did not originate with me, I got it from you tube. Here's an example: youtu.be/bwYkz5S4QCI How to test a motorcycle engine for compression.


In any event, thanks again for your uplifting thoughts!
 

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I appreciate your thread and needless to say I hope you are correct and that I am complicating matters. Nothing would please me more than to learn that it is far less serious than I am imagining. However, I have changed the filter several times. I am on my third since the initial breakdown.


There is no longer any question in my mind whatsoever in regards to the proper method of testing for compression. But the idea that all 4 spark plug holes are to be tested did not originate with me, I got it from you tube. Here's an example: youtu.be/bwYkz5S4QCI How to test a motorcycle engine for compression.


In any event, thanks again for your uplifting thoughts!
That's a four cylinder bike he testing, not a V-twin.
 

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Discussion Starter #40
Someone such as yourself recognizes that immediately, but I began my search without the knowledge, experience and expertise you obviously possess, therefore I took it literally as the caption said "how to test a motorcycle engine..." Thanks to my association with this site I've learned to narrow my search; with a better understanding of what I am looking for, and regardless of what happens in terms of my bike this has been a rewarding experience for me.
 
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