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Discussion Starter #1
Hi everyone! Bad buzz today. Went to ride my ‘07 VStar 650 and No-Go. Wants to start but no dice. 100% gasoline, new plugs and battery (installed today). this link to my GDrive and see what you think. Copy and paste into Google if needed.


Thank you!
 

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check for spark at the plugs, ground one against the motor and see if it sparks.i hope your only using 87 octane
 

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Did you gap the plugs before putting them in? How does the air cleaner look? Does that model Yamaha have the resistor in the spark plug wires? I don't know that's why I ask. I have heard they can cause starting problems.

Is the kill switch in the run position?
 

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the bike was designed to run on 87. 91 burns slower your getting incomplete burn. what did the old plugs look like. the new plugs should have started it.if fuel is the problem. pull a plug and see if you get spark.
 

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Discussion Starter #6
check for spark at the plugs, ground one against the motor and see if it sparks.i hope your only using 87 octane
the bike was designed to run on 87. 91 burns slower your getting incomplete burn. what did the old plugs look like. the new plugs should have started it.if fuel is the problem. pull a plug and see if you get spark.
New plugs are gapped to .031-.035 per users manual and in sync with the ones I took out. Tried plug-to-cylinder-head test on both plugs...no spark. All fuses are in tact, none blown.
62431
 

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Discussion Starter #7
Did you gap the plugs before putting them in? How does the air cleaner look? Does that model Yamaha have the resistor in the spark plug wires? I don't know that's why I ask. I have heard they can cause starting problems.

Is the kill switch in the run position?
 

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Discussion Starter #8
Thank you for the input. Will look into all these things too and report back.
 

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1985 Yamaha Virago 1000
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Keep 87 in that thing it can barely burn that cold start as it is, 91 will be ALOT more difficult to get it to start on. Also owned a vstar and never ever had to worry bout gapping the plugs... Hell I still never had to gap spark plugs. Your spark plugs are definitely shot based off the pictures, and a lot more carbon on there then you want, it should be a light brown color with minimal black at the tip. But you said you have no spark so you pretty much just found your problem, I grabbed this photo from my book of knowledge just for you, maybe it will help.
62432
 

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Discussion Starter #10
Keep 87 in that thing it can barely burn that cold start as it is, 91 will be ALOT more difficult to get it to start on.
So, is your advice to drain the tank of the 91 octane and try it with a 1/2 gal. of 87? What about the gas in the lines?
 

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So, is your advice to drain the tank of the 91 octane and try it with a 1/2 gal. of 87? What about the gas in the lines?
Yeah i'd for sure drain that, throw in 87 and some carb cleaner, should ignite with a smallest spark. You could drain the gas lines too if you really feel like it, but mostly 87 octane and carb cleaner mixing in there should ignite just about damn anything. Oh and while you're doing all this junk, i'd throw in a new air filter too. The 650's are kinda small and get clogged quite easily.
 

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2019 Kawasaki Versys 1000 SE LT+
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If you have a spark, the octane rating won't matter. The only effect of a higher octane rating is to require a higher ignition temperature in order to prevent pre-ignition (knock or ping) on higher compression engines.
 

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If you have a spark, the octane rating won't matter. The only effect of a higher octane rating is to require a higher ignition temperature in order to prevent pre-ignition (knock or ping) on higher compression engines.
Using high octane in low compression engine will drastically effect the performance, mileage, and cold startup. Alright, not DRASTICALLY, but it will definitely make it harder to start and perform efficiently with the wrong gas. I've had the exact bike as OP and i'm talking from experience here lol
 

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Sorry, but as a retired mechanical engineer with a masters degree, 35 years in the industrial engine business, 31 years as a registered professional engineer, and 31 years as a member of SAE (Society of Automotive Engineers), I have to disagree. A spark provides a temperature high enough to ignite gasoline, regardless of the octane rating.... how do you think they start an airplane on 110 octane? (Hint - it's with a spark that's no different than the one in a motorcycle)

Look at a diesel where a typical compression ratio is at least 20:1 - at TDC, the cylinder temp is high enough to ignite diesel fuel WITHOUT a spark. And diesel is a lot tougher to ignite than gasoline. A high compression spark ignited engine requires higher octane fuel so that the fuel doesn't ignite due to high cylinder temperature before the spark ignites it (that's why the proper term is pre-ignition)

Just like the old wives' tale about getting better power and mileage with High Octane fuel..... I can't tell you how many times I've heard this. You need to run a high enough octane to prevent knock - that's all there is to it. Running a higher octane than required is just paying money you don't need to.
 

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Sorry, but as a retired mechanical engineer with a masters degree, 35 years in the industrial engine business, 31 years as a registered professional engineer, and 31 years as a member of SAE (Society of Automotive Engineers), I have to disagree. A spark provides a temperature high enough to ignite gasoline, regardless of the octane rating.... how do you think they start an airplane on 110 octane? (Hint - it's with a spark that's no different than the one in a motorcycle)

Look at a diesel where a typical compression ratio is at least 20:1 - at TDC, the cylinder temp is high enough to ignite diesel fuel WITHOUT a spark. And diesel is a lot tougher to ignite than gasoline. A high compression spark ignited engine requires higher octane fuel so that the fuel doesn't ignite due to high cylinder temperature before the spark ignites it (that's why the proper term is pre-ignition)

Just like the old wives' tale about getting better power and mileage with High Octane fuel..... I can't tell you how many times I've heard this. You need to run a high enough octane to prevent knock - that's all there is to it. Running a higher octane than required is just paying money you don't need to.
A lot of that is irrelevant to me..Like 75% of what you just said. Take an 87 octane bike and give it 91 octane, then take it on a dyno; and come tell me it doesn't hurt performance.... Till then man, "sorry"....
 

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Discussion Starter #19
650 CC & D there is a test here for a no spark condition. get yourself a $30.00 volt ohm meter.might be the pickup coil. run tests before throwing parts at it.
Local bike shop owner/mechanic said it might be the clutch or side stand safety mechanism. He encouraged me to bypass them and told me how. Have not done so yet. He suggested this because I’m not getting a spark. Says it’s not a fuel issue since I can smell gas when trying to start it. Plus theres fuel on the plugs when I took them out to check the gap....
 
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