Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

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jadenvon
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Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by jadenvon » Fri Oct 08, 2021 1:10 am

Hello,
This is my last ditch effort at this site so hopefully I can get some much needed assistance with my motorcycle.
I'll compress the story and details as best I can so here we go with all the info that should be needed.

I bought my 1982 Virago 920 about a year ago now and just started digging into it 2 months ago. This was a barn find and was sitting for 30 years, most likely. The owner had no idea why since he found it in there after buying the property. It wasn't locked so that was good.
As of right now, I have been trying so much to get it going I've been digging seeds and animal fur out of this for awhile. everything is clear except the exhaust. When trying to start, it just keeps on shooting out rust and puffs of fur.
Anyways, Here is everything I have done for it:
- New spark plugs and gaped
- Air filter
- oil and filter
- Cleaned the gas tank of rust and put fresh gas in
- Cleaned gas filter
- Opened timing plate and cleaned up as much as I could with stator and all
- Replaced starter
- Replaced starter solenoid
- New battery
- Checked all fuses and relays, all good
- Kickstand switch is good
- Rebuilt the carbs
- Turned over the engine by hand and it moves and squeaks a little inside (don't know why)
- Coil packs are good and tested for spark as I have it
- I have spark, air, fuel, and fire.
- TCI computer is good too
As of right now, I try to start it up and it sounds like it really wants to run but just doesn't. A few things I have experienced while attempting are puffs from the exhaust - mostly dark grey, fur balls shooting out, rust does too, with exhaust off flames do shoot out (testing purposes), starting fluid doesn't do much when sprayed in cylinders, and most recently I got a backfire out of the air intake hole on the side with a flame coming out of it.

Look, I love working on cars and that's my specialty. This is a whole different game it feels to me, People say it's easier but doesn't seem like it. I fear this is going to turn into taking the engine out and rebuilding it because timing is off or something similar. I don't want to do that. If I do, bye-bye bike. This is my first motorcycle and it would be amazing to have it actually work but that's just not how it goes sometimes.

Any help is appreciated.
If you want photos or videos for extra details, just say so!

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ViragoJoe
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Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by ViragoJoe » Fri Oct 08, 2021 1:35 am

jadenvon,

Yeah, lets start with these:
If you want photos or videos for extra details, just say so!
My friend you've got some major issues going on here that need to be addressed to get this ole gal up and running again.

Be aware, it can turn out to be a money pit along the way! Maybe not. We'll see.
ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


NOTE TO ALL:
:arrow: Please edit your profile to include your location & Bike Information.
It will aid us in assisting you!

jadenvon
Posts: 7
Joined: Fri Oct 08, 2021 12:47 am
Location: Pennsylvania
What Virago you Own:

Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by jadenvon » Fri Oct 08, 2021 1:46 am

You got it! Incoming shortly!

Yeah...Probably why it was put away for so long...

jadenvon
Posts: 7
Joined: Fri Oct 08, 2021 12:47 am
Location: Pennsylvania
What Virago you Own:

Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by jadenvon » Fri Oct 08, 2021 1:58 am

Let me know if there are any specific things you want to see from pictures but here are two video clips that give good ideas into sounds:
https://youtu.be/SUQU-DOLhL0
https://youtu.be/e8wO8YQxklw

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ViragoJoe
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Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by ViragoJoe » Fri Oct 08, 2021 10:01 am

jadenvon wrote:
Fri Oct 08, 2021 1:10 am
Hello,
This is my last ditch effort at this site so hopefully I can get some much needed assistance with my motorcycle.
I'll compress the story and details as best I can so here we go with all the info that should be needed.

I bought my 1982 Virago 920 about a year ago now and just started digging into it 2 months ago. This was a barn find and was sitting for 30 years, most likely. The owner had no idea why since he found it in there after buying the property. It wasn't locked so that was good.
As of right now, I have been trying so much to get it going I've been digging seeds and animal fur out of this for awhile. everything is clear except the exhaust. When trying to start, it just keeps on shooting out rust and puffs of fur.
Anyways, Here is everything I have done for it:
- New spark plugs and gaped (What Brand of Plugs I.D. # and air gap?)
- Air filter (Good)
- oil and filter (Good)
- Cleaned the gas tank of rust and put fresh gas in (Good)
- Cleaned gas filter (Wasn't aware 1982 XV920's had one)
- Opened timing plate and cleaned up as much as I could with stator and all (I'm assuming you mean left side engine cover that houses the stator)
- Replaced starter (Good)
- Replaced starter solenoid (Good)
- New battery (Good)
- Checked all fuses and relays, all good (How do you know all the Relays are good?)
- Kickstand switch is good (How do you know it's good?)
- Rebuilt the carbs (With reference to rebuilding the Carburetors we'll need to discuss this)
- Turned over the engine by hand and it moves and squeaks a little inside (don't know why) (Could be connecting Rod Bearings being Dry from sitting so long. Starter can not spin fast enough to get oil pump to pump oil to them)
- Coil packs are good and tested for spark as I have it (Did you do a Ohms reading to specs on the primary and secondary windings, there can be shorts internally)
- I have spark, air, fuel, and fire. (Pull spark plugs and see if they are getting wet with fuel. Provide pictures of the electrodes and label which is front and which is rear)
- TCI computer is good too (How do you know? How did you test it?)

As of right now, I try to start it up and it sounds like it really wants to run but just doesn't. A few things I have experienced while attempting are puffs from the exhaust - mostly dark grey, fur balls shooting out, rust does too, with exhaust off flames do shoot out (testing purposes), starting fluid doesn't do much when sprayed in cylinders, and most recently I got a backfire out of the air intake hole on the side with a flame coming out of it.

(Do you have a manual for this XV920. Your most important tool!

Okay, you being an auto tech. You probably know that it I were to slam a potato into the exhaust pipe. The car will start and run then die after a short while, due to back pressures stopping the additional spent charges from coming out of the cylinders. Your bikes exhaust is much shorter and exhaust gases will build up faster. You have to clean out the exhaust pipes from any debris that small critters used when they lived in them over time.

We don't know if anyone other than you has worked on this bikes engine. You will need to manually check the timing first. Then we'll look at other things.)


Look, I love working on cars and that's my specialty. This is a whole different game it feels to me, People say it's easier but doesn't seem like it. I fear this is going to turn into taking the engine out and rebuilding it because timing is off or something similar. I don't want to do that. If I do, bye-bye bike. This is my first motorcycle and it would be amazing to have it actually work but that's just not how it goes sometimes.

Any help is appreciated.
If you want photos or videos for extra details, just say so!
=============================================


"Timing The Engine

In order to time the engine correctly you need to have access to the
timing window in the left side cover. This window has a pointer in it,
and by rotationg the crankshaft you can see the timing marks on the
flywheel. There are three marks on the flywheel:

The line with the “T” indicates TDC for the #1, or rear cylinder. The “F”
marks are used to check ignition advance and can be ignored. The single
line indicates TDC for the #2 or front cylinder.

Note: The Virago engine is always rotated clockwise.

Since we are starting from scratch the covers over the upper timing chain
sprockets must also come off.

The upper time chain sprockets have an arrow on them. This arrow is used
to align the sprocket with a timing mark on the head, which is a small pointer at
the top of the cover mounting surface.

When the arrow on the sprocket is alligned with the timing mark on the
head, both valves are closed. The arrow on the sprocket will be pointing
straight up along the axis of the cylinder (not straight up to the sky).

Therefore, for cylinder #1 we need:

a) the timing mark on the flywheel (the “T” mark) alligned with the
pointer in the timing window, and
b) the timing arrow on the rear cylinder upper timing chain sprocket
aligned with the timing marker on the head.

When these two conditions are met, #1 cylinder is at TDC at the point of
igntion and is properly timed.

Note that the piston reaches TDC twice during every 720 degree cycle, once at the
point of igntion with both valves closed, and once at the point between
the exhaust/intake strokes, at which point the the exhast valve is just
closing, and the intake valve is just opening.

As an aside here, if you try to adjust your valves at the exhaust/intake
TDC, you will get a major incorrect adjustment since there is still some
pressure from the cam on one or both of these valves at this TDC.

Note also that the camshaft (upper can chain sprocket) turns at half the
speed of the crankshaft/flywheel. So when the #1 cylinder is at the TDC at
the point between the exhaust and instake strokes, the arrow on the
sprocket will be pointing directly away from the timing mark on the head,
or straight down along the axis of the cylinder.

Cylinder #2
Now we need to time the #2 (front) cylinder in proper relation to the #1
(rear) cylinder. Note that the cylinders do not fire directly opposite
one another, that is 360 degrees apart.

To time the #2 clinder:

Starting at TDC at the point of firing on Cylinderr #1, rotate the
flywheel clockwise until the #2 cylinder timing mark (plain line) comes
into view. This rotation is 288 degrees, slightly less than a full 360
degree revolution.

At this point, set your front upper timing chain sprocket (and thus
camshaft) the same way you did for the rear cylinder, arrow pointing up to
the timing mark on the head.

Congratulations! Your engine is now properly timed.

And now we see that the firing strokes are uneven. Staring with firing
the #1 Cylinder, the #2 cylinder fires 288 degrees later, and the #1
cylinder fires 432 degrees after that (720 total). So the sequence goes
288, 432, 288, 432, etc.

See your manual for details on removal of covers, pictures of timing
marks, etc.
"

Timing Marks
TIMING MARKS XV700 THRU XV1100.png
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ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


NOTE TO ALL:
:arrow: Please edit your profile to include your location & Bike Information.
It will aid us in assisting you!

jadenvon
Posts: 7
Joined: Fri Oct 08, 2021 12:47 am
Location: Pennsylvania
What Virago you Own:

Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by jadenvon » Fri Oct 08, 2021 11:02 am

This is great info, thank you! I will have to dig into this in a few days since I'll have proper time then. I do have a manual but doesn't explain this as well as this.

I'll inform you on the results soon!

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ViragoJoe
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What Virago you Own: 1996 Virago Special XV1100SH

Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by ViragoJoe » Fri Oct 08, 2021 12:54 pm

jadenvon wrote:
Fri Oct 08, 2021 11:02 am
This is great info, thank you! I will have to dig into this in a few days since I'll have proper time then. I do have a manual but doesn't explain this as well as this.

I'll inform you on the results soon!
Okay jaden,

Oh yeah, don't forget to do a compression test on the cylinders. Make sure you do it with a (WOT) Wide Open Throttle.

She needs to gulp as much of the Fuel and Air Mixture as possible to compress. Other wise your readings will be way off.

Timing


The Virago engine is a four stroke engine. Starting at the point where the fuel ignites (the cylinder fires), here are the strokes:

The first stroke is the power stroke where the piston starts at the top
and is pushed down by the burning fuel. This is the stroke that puts
power to the crank shaft and turns it. Both valves are closed.

The second stroke is the exhaust stroke. Here, the exhaust valve opens
and, as the crank shaft turns, the piston rises to the top again, pushing
the gasses from the burnt fuel out the exhaust port.

The third stroke is the intake stroke. As the crank continues to turn,
the intake valve opens, and the piston goes back down, sucking fresh fuel
mixture into the cylinder.

The fourth stroke is the compression stroke, where both valves are closed
and the piston rises to compress the fuel mixture to prepare it for
ignition, or firing.

So for each ignition the crankshaft and attached flywheel turn two times or
720 degrees. The piston reaches its top position (known as "top dead
center", or TDC) twice for each ignition, once when the plug fires, and once
between the exhaust and the intake strokes. This is known as Wasted Spark.

In Summary:


Your Virago has Electronic Ignition. The (TCI) on your Virago is Transistorized Controlled Ignition.

It is the mechanical movement of the flywheel that passes the pickup coil twice that triggers the TCI to fire the spark plugs twice. Once for each revolution it makes during the 4 cycle combustion event. One bang, however, two spark events. Both when the piston reaches TDC on the compression stroke and again when it reaches TDC when it has pushed the exhaust gases out of the cylinder. 2 sparks, but only one bang after the compression stroke. The next time the piston gets to TDC Top Dead Center is right when it pushed out all the exhaust gases. Then the plug sparks again. Since it is void of any compressed air and fuel. Nothing there to ignite it just sparks and nothing happens (Wasted Spark).


More info tips:

Go easy on the starter, when trying to start the bike. Do not prolong the starting process. Allow the starter to cool down between the starting attempts. Just picture yourself trying to kick start 920cc's. You wouldn't last a minute. So, give your starter a break. They are easy to wipe out, for we forget how hard it is to start 920 cc's (56 cu in's). 460 cc's (28 cu. in's) per cylinder.

Back in the day 650 cc's kick-start Triumph's and BSA's were a real challenge when they didn't want to start. I'm still out of breath.

1981 to 83 Yamaha Ignition Test Procedure (Below):

Click Image to Enlarge:
1981 to 83 Yamaha Ignition Test Procedure.png
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ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


NOTE TO ALL:
:arrow: Please edit your profile to include your location & Bike Information.
It will aid us in assisting you!

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audiopro2001
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Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by audiopro2001 » Sat Oct 09, 2021 10:49 am

Our beautiful Viragos can be and at times are VERY finicky gals. They are incredible pieces of engineering technology but with everything that is as beautiful as they are, it can be frustrating.
CARBS CARBS CARBS.
One of the very first things i do with my rebuilds is pull off the carbs. Dont detach them from each other though. They NEED to be cleaned and cleaned very thoroughly. I dont trust a bike shop to do this anymore. The shop may make attempts to do a good job but they never seem to pay close enough attention to our gals needs. The idle circuit in our carbs regardless of whether they are Hitachis or Mikunis is incredibly important to the starting, idling and 1/3 throttle turn of our bikes. I use a .08 high E guitar string to gently probe and clean ALL the passages in the carbs. It is IMPERATIVE that the very small passages of the idle circuit be clean and free of any obstruction. If you don't pay attention to this detail you will have hard starts, rough idling, inconsistent throttle response and potentially she may only run on one cylinder or the other. I have yet to find a shop that pays this kind of detail to a carb clean. Now that you have your carbs cleaned properly it is very important to check and if necessary adjust the float levels. Check the manual for exact float adjustment. I always do mine using the clear tube method. The level should be for the most part about 1 mm below the seam between the float bowl and the carb body. Do not set this too high as the excess fuel coming into the carb will flow into the intake, flood the cylinder and find its way into your engine crankcase and severely contaminate your motor oil. Watch closely how the float levels are set because it is a quite precarious setting to get adjusted to spec. Once you have these things done.... Dont rush to put her carbs back on stop and take the time to "bench synch" the carbs. This is fairly easy to do and will give you a specific point to work from. Adjust all idle screw settings so the slides are sitting down and resting at the bottom of their movement. Using the carb with the throttle cable attachment (should be#2 the carb on the right when installed for the front cylinder) Turn it until you see the slide move. Using two matched diameter small round pins put each pin under a slide of each carb let the slide settle on the pin. Now gently adjust the carb synch screw until the number one (left carb) just starts to raise off the pin. Now adjust the synch screw so that that slide just settles back on the pin. Turn the throttle cable fitting slowly and watch to see that when released both slides just sit down on the pin and that as you raise the slides with the throttle fitting watch closely and be sure that both slides raise off the pins at the same time. Once you are satisfied with the synch screw adjustment and that the slides are moving at the same time remove the pins and turn the idle speed adjust screw under the throttle cable fitting to a place where it just begins to raise the slides. This is what is called a bench synch. Once you have the engine running carefully adjust the idle speed screws so the engine idles at between 950 and 1050 rpm. When you have that idle speed screw adjusted to the proper idle then go to the left side carb (number 1 or rear) and adjust that idle screw until it just touches the throttle shaft stop but dont increase the idle with this screw. Once its just touching the stop screw the lock nut up into place and carefully tighten it down being aware to not change the idle speed that you have already set with the idle speed adjust screw on the right side carb. If you can do all of these things getting the cleaning done right, float levels set to spec and bench sync the carbs as long as you have good fuel flow into the carbs the engine should start and once she does try to get that idle speed set right away. Resist the temptation to rev the engine via the throttle until you have the idle speed set. Then a little mild revving is fine. Listen to her as you do a little revving she will tell you all kinds of things like if you have a vacuum leak or an intake air leak.
Carb cleaning and proper initial adjustments will give you a very stable and predictable starting point to attempt any further adjustments or changes to the engine. Unless you have some major cam timing issues the engine timing is managed by the TCI, it can not be altered with the stock TCI.
Good luck and let us know how things shape up. We learn from each others experiences when the whole story gets told!
Brian "audiopro" Houle
Living in the beautiful northern part of Minnesota.
I love it here!

1982 Virago XV920J
C5 Optically encoded ignition system
Mikuni VM34 round slides
Riding on Kenda Rubber
Complete LED Lighting for the entire bike
Desperatly working on EFI Design :lol: :lol:

Space hopper
Posts: 42
Joined: Sat Jan 23, 2021 12:28 pm
Location: UK Yorkshire
What Virago you Own: 1983 XV500K

Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by Space hopper » Tue Oct 12, 2021 11:35 am

Hi, excellent advice above, my xv500 (imported from Minnesota) was an absolute devil to start after recommission ( stood for 30 years) , I couldn't find anything wrong with it, just refusing to start, I can't tell you how many times I stripped carbs, eventually it started to fire (and backfire) and just got better and better, it did take a long time to get to that stage. I never found the reason for not starting but now starts with full choke, first touch, If I have not started it for 2-3 weeks it becomes reluctant to start, when you get to a running state keep starting it and run up to working temp once a week, I know there is no practical advice in my post, there are other posters on this forum with far superior knowledge than me, this is only my opinion and it worked for me. Good luck and keep going

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ViragoJoe
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Re: Not Starting 1982 XV920 Virago Chain Drive - At Whits End (Pennsylvania)

Post by ViragoJoe » Thu Oct 14, 2021 1:43 pm

audiopro2001 wrote:
Sat Oct 09, 2021 10:49 am
Our beautiful Viragos can be and at times are VERY finicky gals. They are incredible pieces of engineering technology but with everything that is as beautiful as they are, it can be frustrating.
CARBS CARBS CARBS.
One of the very first things i do with my rebuilds is pull off the carbs. Dont detach them from each other though. They NEED to be cleaned and cleaned very thoroughly. I dont trust a bike shop to do this anymore. The shop may make attempts to do a good job but they never seem to pay close enough attention to our gals needs. The idle circuit in our carbs regardless of whether they are Hitachis or Mikunis is incredibly important to the starting, idling and 1/3 throttle turn of our bikes. I use a .08 high E guitar string to gently probe and clean ALL the passages in the carbs. It is IMPERATIVE that the very small passages of the idle circuit be clean and free of any obstruction. If you don't pay attention to this detail you will have hard starts, rough idling, inconsistent throttle response and potentially she may only run on one cylinder or the other. I have yet to find a shop that pays this kind of detail to a carb clean. Now that you have your carbs cleaned properly it is very important to check and if necessary adjust the float levels. Check the manual for exact float adjustment. I always do mine using the clear tube method. The level should be for the most part about 1 mm below the seam between the float bowl and the carb body. Do not set this too high as the excess fuel coming into the carb will flow into the intake, flood the cylinder and find its way into your engine crankcase and severely contaminate your motor oil. Watch closely how the float levels are set because it is a quite precarious setting to get adjusted to spec. Once you have these things done.... Dont rush to put her carbs back on stop and take the time to "bench synch" the carbs. This is fairly easy to do and will give you a specific point to work from. Adjust all idle screw settings so the slides are sitting down and resting at the bottom of their movement. Using the carb with the throttle cable attachment (should be#2 the carb on the right when installed for the front cylinder) Turn it until you see the slide move. Using two matched diameter small round pins put each pin under a slide of each carb let the slide settle on the pin. Now gently adjust the carb synch screw until the number one (left carb) just starts to raise off the pin. Now adjust the synch screw so that that slide just settles back on the pin. Turn the throttle cable fitting slowly and watch to see that when released both slides just sit down on the pin and that as you raise the slides with the throttle fitting watch closely and be sure that both slides raise off the pins at the same time. Once you are satisfied with the synch screw adjustment and that the slides are moving at the same time remove the pins and turn the idle speed adjust screw under the throttle cable fitting to a place where it just begins to raise the slides. This is what is called a bench synch. Once you have the engine running carefully adjust the idle speed screws so the engine idles at between 950 and 1050 rpm. When you have that idle speed screw adjusted to the proper idle then go to the left side carb (number 1 or rear) and adjust that idle screw until it just touches the throttle shaft stop but dont increase the idle with this screw. Once its just touching the stop screw the lock nut up into place and carefully tighten it down being aware to not change the idle speed that you have already set with the idle speed adjust screw on the right side carb. If you can do all of these things getting the cleaning done right, float levels set to spec and bench sync the carbs as long as you have good fuel flow into the carbs the engine should start and once she does try to get that idle speed set right away. Resist the temptation to rev the engine via the throttle until you have the idle speed set. Then a little mild revving is fine. Listen to her as you do a little revving she will tell you all kinds of things like if you have a vacuum leak or an intake air leak.
Carb cleaning and proper initial adjustments will give you a very stable and predictable starting point to attempt any further adjustments or changes to the engine. Unless you have some major cam timing issues the engine timing is managed by the TCI, it can not be altered with the stock TCI.
Good luck and let us know how things shape up. We learn from each others experiences when the whole story gets told!
Hello Brian (audiopro2001),

In your superb write-up above shouldn't the words Slide or Slides be Butterfly or Butterflies?

The Butterfly (flies) are controlled by throttle linkage and the slides are controlled by the Diaphragm in each Constant Velocity Carburetor and not by the throttle linkage.

If you concur, we can change them for you.
Please advise.


1982-yamaha-virago-xv920-y473-1-carburetors-carbs.jpg
Joe
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ViragoJoe 🇺🇸
1996 XV1100SH Virago Special
"Never ride faster than your Guardian Angel can fly!!"
;)


NOTE TO ALL:
:arrow: Please edit your profile to include your location & Bike Information.
It will aid us in assisting you!

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