Bike wont start...can u take a look

[way2faded]

K its a 86 vf500f

Ran fine on sunday of last week...didnt ride all week.. went to start her up lastnight... turns over... almost started once.. then i heard almost like a backfire sound out of exhaust pipe....

Let it sit for 20.. cameback out tried to start nothing..

checked gas... upon checking oil... i noticed it was very low.. like scary low

would there be somthing that would prevent it from starting if engine oil is low.... the oil light was not on till after i try to start then it comes on...Im not real technically inclined.... but the bike was serviced 1900 miles ago... and ran like a champ started up perfect till last night..

Im hopin it might jus need oil....but can any1 verify if that would prevent it from starting?

Thanx for any help..as I have lil to no knowledge at all on motocycles, I would dread having to borrow a truck to haul it into a dealership...I only know just what ive read in the manual... and i did replace a bent brake lever with help from the repair manual off this site

[Fizz]

Oil (or lack thereof) won't prevent a bike from starting unless the oil levels been low long enough to cause the rings/piston/cylinder to wear/overheat to the point where there is no longer sufficient compression to ignite the incoming fuel/air charge and/or engine components have warped/seized and causes moving/touching components to bind. Also, oil is one of the main cooling components of the valve train (to which mid 80s VFs were notorious for failing), lack of oil can cause valve train damage by increased wear and overheating.

You said the engine is cranking over, I would more suspect something electrical, it is the weakest link on engines.

You'll want to inspect/test your Regulator/Rectifier, Battery, fuel pump, petcock, spark plugs, fuses, etc. Investment in an engine compression guage wouldn't be a bad idea either.

Though it is unlikely that your engine has seized (making the starter have a VERY hard time cranking), it is possible.

If you don't have a service manual, now's the time!

[way2faded]

tnx for the reply...

like i said it turns over fine when the bike starts I generally have to turn the choke halfway on..let it warmup for a few mins then turn the choke off and its ready to go... it wont even start with the choke on(which i know your not really spose to do) .. the bike only has 18.5k on it.

Heres a ? tho, if i left the petcock turned to ON for several days.. could that have caused this.... i religiously turn it off everytime i shut the bike down... but when i got home last Sun.. i left it turned to the ON position and it was left on all week.....

Ima stop on the way home from work pickup some oil... fill it up... and give it a try....man i hope i dont have to haul the thing into the dealer....have to wait like 2 weeks just to drop it off.

[way2faded]

ok so i got home went out tried to start it... nothing

waited 10 min... tried... roll on the throttle a bit when i pushed the starter...and it started...when i let off the throttle it died...

started it again the same way.. this time i held on the throttle.. in N at like 5k RPMs for like 30 seconds... then released throttle and it idled.

So i killed it....and tried to start it up normal... and she did.

Is this common with the older bikes? Is it okay to give it throttle when starting.,.. I never have b4.. but it seems to be okay now and starting right up.

[GreyVF750F]

Sounds like you semi fowled a plug or two. Only time you should need choke is starting with a cold/cool engine. Put some oil in it then take it out where you can redline it in the first 3 or 4 gears a few times. That will clean the plugs if they are not that bad. With todays gasoline it may be leaking by the needles of one of the carbs and flooding that cylinder. It's becoming a common problem with some engines that use carbs. Shut your gas off over night or longer and see what happens.

[eddievalleytrailer]

Yeah, Sounds like you fouled a couple of plugs. Might be time for a new set. My old Sabre does that every once in a while.

[loopsandlogic]

I always need to blimp my exhaust when starting her in choke in the morning.
But i don't have to hold it for more than 2 seconds.

Then i can control her with just the choke. Also, cause I was doing a ton of adjustements on her recently, I fouled all 4 plugs from using too much choke always.

I put new plugs in her, and she purr's like a swiss watch.....if they could purr:)

Good luck

[slippy]

The petcock is vacuum operated, so even if you left it on, no gas will flow since there's no vacuum being provided. Unless of course the diaphragm is ripped or torn inside the petcock.

[thomas lloyd]

on the left side of your bike theres a 30 amp fuse check that if it blows it will turn thestarter but wontfire up