Help me with my VF500!

Ok, the tube gets plugged tomorrow....

I took the batter over to o'reillys and had them test it, it tested good and was completely dead, so they charged it and the bike started right up with it in...

Carb boot ordered... Here is my next thing I noticed...

The power over 6K rpms was gone today. This was the first time I got it up over 5K since I started working on the carbs. It seemed almost like they weren't getting enough gas or something. It would get to 6K just fine, and from about 6K-8K it studdered some and there was some clicking noises when it would miss. (it seemd like this is what was going on, but i'm no expert as you all know very well ) The only thing I was thinking was that it could be the spark plugs. I tried to get one out, but the socket I have won't go down far enough to get it, I will have to try to find a thinner one tomorrow. Any other ideas?

Sorry if I seem like I don't want to accecpt advice, just nervous about messing this thing up bad, and want to double check things. Thanks again for help!

 

Do you have the factory tool kit? The factory spark plug tool fits in there easy enough, but for the left rear cylinder especially it's going to take some manuevering. What I do is loosen the plug with the tool a quarter turn, remove the tool then use my two point fingers to rotate the plug out.

The stock replacement plugs are DPR8EA-9s.

I wouldn't bother toying with it until you get the new boots. Have you replaced the air filter yet? Your bike probably needs a valve adjustment, full carb synchronization and pilot adjustment (Are the metal plugs described on page 150 of the clymer manual removed?).

Your ignition wires aren't stock, so who knows what could be going on in that department either.

 

MAN, you're persistant!!

AS above, get familiar with sparkplug removal/replacement since that's an essential skill. Factory tool kit socket is best to use.

no power over 6000 sounds like maybe a vacuum slide (or 2) not rising, either because of improper diaphram installation or hole in diaphram....

You'll get it sorted eventually because you don't stop trying!!

 

i'm persistant because I really want to get this thing running good enough to drive 20 miles to work and back by summer...

I don't have the factory tool kit which is causing problems...

Pilot Jets and vacuum slides are next in line I think (the vacuum slide is the black thing in the carbs that the needle runs through? right?)

Then Valve adjustment...

I have not gotten a new air filter yet...

I plugged the tube !! It hasn't ran any differently...

Help and suggestions are appreciated as always

 

Yeah, the slider is the black thing with the diaphragm on it. The should move smoothly but not too slow or not too fast. When you press them in, they should move smooth and kinda softly 'tap' when it bottoms out, but shouldn't 'smack'.

If your air filter element is dirty, all sorts of things can go wrong.

Why would plugging the tube make it run differently? The only thing that's happening now is that that "smoke" is now going into your airbox where it'll be burned off instead of just let out to pollute (and make people look at you like "Why is there exhaust shooting out of the tube on that guys bike?")

 

haha, good point on the tube thing, but wouldn't it spark worse because it has less air, and more smoke? Like smothering a fire?

I'll get a new air filter this coming week, and i'll take the carbs off and check out the sliders...

thanks again!

 

Don't take the carbs off to check the sliders!!.,.,.. just watch them move while you rev the engine after removing the air filter.......all 4 should rise and fall the same with changes in rpm.

Forget about the tube; it's not important.

 

The only problem I see with that is... It doesn't seem to have problems unless i'm actually driving, when reving the engine in the drive way it seems to rev up fine (this may make since still, if it does, just tell me the STFU and watch with the carbs on )

 

VeryFunRide has it right.

Although, you don't need the bike running to check the diaphragm sliders. Take the top off the airbox and use a long screwdriver to move the slider. Do it gently in case the rubber diaphragm is pinched or other problems are encountered. After moving it about 1 - 1/2", remove the screwdriver. If it "SMACKS" down, then the slider diaphragm is either not mounted correctly or there is a hole/tear in it.

There is no known way to reliably repair a torn diaphragm - although I've had several ideas I've yet to test. (anyone want to send me a slider with a torn diaphragm?)

Slider replacement is the only solution.

 

I've seen two different size spark plugs. If you have the bigger one you may need to grind down the outside of the socket. Mine is already gound down and it fits fine. I had to do that for a previous bike.

Chris

 

Well, the sliders seem to be all working well, the first one had a spot about half way up that it sticks, and then continues on, I will prrly take teh carbs off tomorrow and take at least that one apart to make sure everything is in order...

 

Ok, i got it out today in the sun where I could really see the sliders. They rose all at the same time, but didn't seem right. When I opened up the throttle it seemd very loud and the sliders were vibrating a lot. They wern't in a solid position, it was very fast up and down movements to keep them at close to the same level at all times.

I put the airbox and gas tank back on and took it for a ride to warm it up. When I stopped I rev'd it up and just rolled the throttle and it got to 7K and would not go any higher, I had it WOT, yet the rpm's would not rise. I let go of the throttle and reved it up again and it went to 8K this time, I let go and went again and it would get up to 9K. I don't know what could be causing this problem, i'm kind of lost.

One thing that I did notice was with the tube plugged there is thick tan grease that is comming back up into the air box. The metal screen filter had the grease in it, and when I took the airbox off last night and started it the tub pumped out several table spoons worth onto the motor (noticed it when it started smoking like crazy burning off) But this just doesn't seem normal at all...

Any help appreciated as always!!
Thanks TJ!

 

You are right, that is not good....I would bet that you breather hoses are ran like in this pic....



Now take a look at the pic, see what is wrong? The LONG tube going to the top ( intake plate ) is attached wrong. It is on the "low" attachment...Now look at the short tube facing "down" near the line on the ground. It is plugged into the "high" tube. this one is the one you plugged, this is the drain for the breather system. NOW, what do you think would happen if this was on the bike? The short tube ( going left ) is attached to your engine near the #3 cyl. Oil / air enter into this tube to the black box. Well Oil is heaver than air, so the oil will sink to the bottom of the box. Now you have pressurized air blasting out of the crankcase and coming through the short tube, and you plugged the 3rd tube. So the air coming in is forcing the oil up to the intake to puddle around the carbs.

Now if you reverse the setup and have the long tube facing "up" pluged into the "high" attachment, and the drain tube plugged into the "low" attachment, what will happen? air comes through the small tube into the black box. Oil is heavier than air so it will puddle at the bottom of the black box. The drain tube is attached to the "low" side and oil will drain out of the drain tube when the PLUG is removed from the drain tube.

Hope this helps.....

 

the tube setup is NOT responsible for your running problem, although excessive pressure through the breather vent could indicate some internal engine problem like cracked piston rings or damaged piston, and a compression test could confirm this.

 

New problem popped up today... Doesn't look good

I went and got gas for the bike, wanted to see if the problems above 7-8K may have been just lack of fuel. The bike ran great, i took it around town, getting it up to 55 on a rode to the outside of town, and it ran great. Went through gears like it was running perfect, so I think I fixed the fuel problem. I was really trying to see if the bike will be able to make the 60 mile trip home in a few weeks if I don't get around to adjusting the valves (really wouldn't have much choice, plan to take back roads and drive 55ish, with several stops along the way)

So anyways, I got home on the bike, and was happy with how it ran. Watched the heat gauge the entire time and it was barely over half way up at any time. I checked the oil before heading out and it was good. I stopped the bike in the driveway and was going to let it idle for a sec and walk around making sure everything was in order, that was when I saw this...



Oil running down my frame and dripping onto the ground. I shut the bike off right away and tried to figure out where it was coming from. I never could find a direct point that it was coming from. I checked the oil level and it was good.

Does anyone have an idea what could be the problem here? The only thing I can think of is that the bolts weren't tight enough and it was just leaking out around the gasket... What should I look for?

 

Dude you just lube the chain? Lube can sling off and look like black oil. Feel it, if it's sticky it's chain lube.

Your headcover gasket may be leaking. I forget who on this forum said it, but the VF500 headcover gaskets aren't bolted down with the bolts you see on the cover. Rather, the bolts bottom out into their respective holes, the bolt head then compresses a rubber ring which then presses the headcover into the head.

Clean it up, find out where the oil is coming from.

EDIT: Err, I didn't see the picture the first time. Just clean the area up and note where it's coming from

 

I lubed the chain about a week ago, havn't done much riding since then, just around town at 30 or so... This was the first time I got the bike over 70MPH so that would probably make since... I cleaned it off and tried to find where it came from tonight with no luck at all, I flicked the off switch and pressed the starter to drain the oil from the pump, I tilted the bike both directions, and found no oil going anywhere...

Gonna try to do the valve adjustment next week when i'm back from atlanta... Assuming that was just oil from the chain lube, i think it will make it home just fine on the county backroads

Thanks again VFR, great help as always

 

Dude, absolutely certain that has nothing to do with the chain. It's on the wrong side of the engine for one thing.

That's a significant amount of oil leakage. I would think that the source should be pretty easy to locate. Just take a clean paper towel and start wiping around the area. Start low and work your way up, oil does not tend to leak upwards. With that you'll be able to narrow your search. I'd say you are on the right track with your idea that it could be the clutch cover not being tight. I'd check all of those bolts to see if they are tight.

Figure out where it's coming from, then the solution will present itself!

 

2nd vote for the cover...if the gasket is shot, I have had great results with a fast drying black gasket maker i picked up from autozone. It's the one you have to set in 5 min, and it is ready to ride.

quick tip - when taking off that cover, roll the bike up onto 2x4's and put the bike on the kickstand, that extra lean that is given by the additional ~2" lift from the wood will keep the oil in your bike, you will have VERY little actually leak out when you take that cover off....

 

Is your oil fill cap on tight - and with an O-ring? If you have a separate dipstick - same question.

Always, ALWAYS check the simple stuff first!