Octania

I had one back in CA, many years ago. Decided to procure one here.

After weeks of seller hard to get ahold of and then title problems I finally have a 81 Virago 750. Evidently it has been worked on by a moron. Rubber tube hanging down by the rear tire I have not traced other end to yet. Rear License Plate bracket missing- blade from '67 Cutlass flex-fan fixed that.

Starter button broke off- fixed with chunk of vacuum line and a #4 bolt...

Backfires upon decelleration- Individual pipes, supposedly jetted correctly for them but base on what I have seen otherwise... doubt it.

I see this thing
http://www.ebay.com/itm/YAMAHA-VIRAG...92a26a&vxp=mtr


"HERE IS A VIRAGO AIR MIXTURE VALVE THIS PART COULD FIX YOUR TROUBLE IF YOUR BIKE IS COUGHING AND SPITTING USED ALOT ON THE EARLIER MODELS. "

under the cover on the left front top, vaguely recall the previous bike needing this fixed or replaced. This bike's unit has duct tape around it as if broken and taped shut. It has exactly 2 vacuum hoses, lg and small. One to inlet between front carb and jug. Other to ???

Wondering if this is something I can just plug the hoses to or does it NEEEED the $$ replacement part?

Parts or experience from others appreciated.

Most of the wiring seems to work despite several chafed spots under the seat, thru to the wire. Taped over all that sort of thing.

Professur

Never worked on one. Indeed, only rode one once. Developed a serious dislike for it. Couldn't get off it fast enough. My respect to anyone who can take one into a deep turn.

stellar

I had a virago 1000. Hated it. It backfired on decel too, but pipes weren't OE. Rubber hose by tire is probably battery overflow. Don't remove it or acid will get everywhere. Front end was squirrley. Fortunatley a head on collision with a jeep forced me to get rid of it. Ins Co. totaled it. A couple of years later, I got an 82 FXWG harley wide glide. I like it much better. Have had it for a good number of years now. I totaled a 56 Harley pan head in the early 70's a tractor trailer ran me over on I 10 near Albuquerque NM. Totaled that one too. Be careful on those things, they can be dangerous. Lucky twice, I'm hoping 3rd time isn't the charm.

Lady72nRob71

Or carb vent tube. During steeper bank angles, fuel could leak from the vent, hence the tube to allow it to drip out away from the hot engine.
My Harley has one for this purpose in same location.

Post a picture of the bike when you get a chance!

Octania

I just put a new battery in it, with a clearish vent tube, so I know that thing.

Today I had the ign switch ALL apart and I mean ALL apart to see why it would not engage the fork lock... never did find out why the lock cyl would not turn more after depressing in, so i gave up understanding, cleaned and lubed and re-assembled to find that it now works like it should. More or less. Fork lock works fine. All is smooth and suave. It had dirt in the fork lock actuator, and old sticky grease.

Test ride with Mixture Control Valve removed and both vacuum lines, which both go to the front cyl. "straight-thru" = the part between carb and cylinder- are now removed/ plugged. I ran straight-thru vacuum only to the RH petcock for fuel .

Sputters / misfires at light load like before, still backfires on dec'n, and sometimes the carbs do not come down to idle like they should upon stopping. I am thinking anything PO touched needs to be re-touched, by me. Clean carbs out, verify operation of vacuum actuators for the slides, maybe re-jet a little richer per plugs' tales.

PO says the heads were re-done by "Dowker" - a well known engine shop- but no telling who did the R&R and it looks like they broke or failed to connect many things. Final drive oil looks good though.

It runs and goes. Loud pipes. Just need to eradicate that snarly exhaust and surge at light load.

Octania

drained all the gas out today hoping it was watery fuel but no. Drained both carbs too. Founs that the mystery hose near the rear tire goes to a filter? which drains? to the ground, appears to be the air vents for the carbs' vacuum operated actuation- not unlike a Holley carb secondary opening.
If it still runs the way it did I guess I will have to remove the carbs and see what they look like inside. Clean and lube. Adjust what can be.

The front pipe is a lot bluer than it was, front cylinder seems to be runnig hotter than the rear. I have heard that Harleys can pop thru the xst if one re-uses an exhaust pipe gasket and it draws air in on deceleratrion.

here is a pic or two

Octania

Took the carbs right on off last night.
Not the dirtiest ever seen, but pretty filled with crud, and one "jet" was just totally obscured with green buildup. Evidently whoever just had them off and put new needles and seats in did a semi-rectal job on other things. Some of the items were not even removed and cleaned. I think I can do a lot better.

All the brass stuff has been in the gallon of carb chemical overnight. If the green stuff still obscures the 0.5mm? hole [stamped "50" but obviously not 0.050"] then will try vinegar/ salt which works SO WELL on electrical terminal cleaning.

As you can see I prefer metal gas cans over the plastic crap they make nowadays.

Lady72nRob71

Nice looking old bike - I like those wheels.
I am sure the carb cleaning will help. I cleaned out mower carbs that looked like that and they ran perfect afterwards.
I use metal gas cans too, even if I have to strap the handles back on! I bought one plastic one long ago and it cracked and leaked two years later. Poor engineering there...