NEW (for me) 86 VF500

Since you use a screwdriver to remove and install the pilot jet, I understood that as what he mean. The idle mixture adjustment screw does not come to mind when referring to the slow speed jet. Sorry for the confusion.

Do not do this. It will make that carb run fully lean even while cruising. You would damage the engine doing so - a burn valve at least or possibly worse!

 

Tink, you once agian have shown that you clearly do not understand the operation of these bikes! The needles adjust the fuel flow, not air like a dirtbike carb. The engine uses only this flow to feed that cylinder during cruising throttle openings. Will it damage the engine? I'm not 100% sure about that, but I certainly will never run any of my engines under those conditions.

Please do not assume what I would say about something - it's better to ask my opinion than the state a false accusation as you have here.

 

I talked to the Service Manager at the shop where I work and told him my tragic tale of the stuck air screw. He said that they get stuck jets from time to time and that the fix is expensive (sometimes) and like the original comment it is best to just by pass that one, clean it as best I can and hope for the best. I will post and let you all know how it goes. I am probably making too much of this.

My understanding of the low speed circuit is that it only comes into play when the throttle is closed and the slide is shut. It’s sole jet is a tiny hole in the carburetor throat. Once the throttle is open, even a small amount, the secondary midrange jet takes over. This is sometimes referred to as the needle jet. In any case proper fuel/air mixing will take place and no lean condition will occur. If you could lean out a carb by messing with the low speed idle screw, the nation’s roads would be strewn with bikes with holed pistons. People just can’t seem to resist jacking with that screw whenever their bikes starts running poorly for whatever reason.

 

Actually, the slow circuit is also used during cruising speeds. Up to 10-15% throttle the mixture is controlled primarily by this circuit. Considering that the vast majority of the time you are at small throttle openings/cruising speeds this means the idle mixture is possibly the most important part of street carb jetting.

The main jet can cause the most damage in a short amount of time, but you have to run WFO for this to happen. The slow speed mixture will cause a slow death to the engine is it off too far - that's my concern in this case.

 

I wanted to update my story and let everyone know that I got it all back together today and took it up the road about three miles round trip. There were some trials and tribulations along the way. You know from my previous posts that I had a stuck idle mixture screw. I discussed this with the service manager at the Honda store I work for and he said “it happens.” You have to weigh the benefit of removing that stuck screw with the cost of possibly buggering up the carb body. I opted for wait and see and I am glad I did. The second tale of woe happened when I got the cooling system back together. Once the system was filled with coolant every seal and pore began to bleed water. Not a lot mind you but enough to make the motor wet in the cylinder crotch and to leave a spreading wet spot on the ground. I panic very easily. I talked via email to tinkerinWstuff and he talked me down, telling me that many times these old seals tighten up once you get the motor hot.

That’s what happened this afternoon on the initial run up. The water leaks, for the most part have vanished. The carbs, while installed dry, never leaked a drop. The petcock weeped a little but seems to have stopped. I reworked the petcock to bypass the vacuum valve. The bike fired instantly and with none of the cold natured starting that was exhibited at purchase. This is my first time out on a real road with the little VF500F and my impressions are really good. I like this bike a lot. You have to understand that I am really used to riding my old Norton so the power characteristic are really different but not bad. It makes power in the higher rev ranges but there is no flat spot or surge like some high revving motors. Years ago I have a couple of 350 Moto Morini’s They were small, light weight bikes that were ever so much fun to ride. The FV500F reminds me a lot of them. I was really concerned that because the bike shows signs of having been thrown down the road that it might have been seriously bent (There is a ding in the frame.) No evidence of poor handling showed itself today. I think we are going to get along just fine.

Now for the bad. The shifter placement, in conjunction with the side stand gave me nothing but grief. I could only shift with the edge of my boot and in reality it started to hurt my foot to shift. In all fairness the shifter is bent but you have to admit that the side stand placement is pretty poor for a Honda. This shifter issue will need looking into. The stock mirrors are worthless. It might be that I am a big, broad shouldered lad but all I can see in the mirrors is my arm pits. It could use bar end mirrors if the bar ends weren’t welded up solid. Other than this it ran like a happy little camper. I ran it up to around 60 mph with no issues at all.

Things I have done:
Cleaned carbs
Reworked petcock
Installed Ebay supplied left clip-on
Installed new spark plugs
Had radiator cleaned and a leak fixed
Bought and installed an Ebay chair guard
Fixed the foot peg mounts by using the proper bolts
Fixed the rear wheel axle and chain setup
Did the paper work, title, insurance and tags

Things left to do:
Change oil and filter
Get state inspection
Replace upper and lower farings
Ride the piss out of it.

 

WHEN the question is why you chose to buy THAT old heap rather than spend a bit more to purchase a gen2 or 3, far more useful and reliable machines, then the question is WHY??

If you thought you'd get a good, rideable bike cheap you were wrong on both counts .

Baby that motor or have it on your bench awaiting parts.

 

I am under no delusions as to the reliability or longevity of my chosen ride. Due to my past fascination of British and Italian iron I seem to always have something on my workbench awaiting parts. The whole choice of bikes comes down to one of simple math. I purchased this bike for $500. I have less than $800 in it ready to roll. A nice Gen 2 or 3 puts me in the $2300 range at least. If I could find a later model VFR for $500, even one that was cosmetically challenged, I would jump on it in a heartbeat. For now, I am going to do the regular maintenance, do some minimalistic repairs and ride my little Interceptor for as long as it lasts.

 

To me the joys of riding are enhanced by riding something that I had a hand in making right. I guess it is like riding a custom bike in that you have the knowledge to ride a bike that not many people can. I know, without my skills, this bike would be rotting in someone's shed or laying forgotten in the back of someone's garage. I hate it when a perfectly good bike, with lots of miles left in it, is relegated to the trash or breaker. There is also the added bonus of pulling up in a parking spot and having someone wander over and say “I had one of those a long time ago!” I love meeting people and these older bikes are a great conversation starter.

 

That's really common. I removed the rubber piece from the stand and cut the metal holder off completely. That made a huge difference. Still not perfect but better. Also make sure your stand pivot bolt is tight.

Once you have that fixed maybe you can help us out with the rodent problem we have on this forum. In typical rodent fashion, it went away for a while but now it's back.

 

I did pull the side stand and it is easier to shift but I am afraid the squirrelman just might have been right about the reliable ride thing. It turns out that my second ride down the road has turned out less than perfect. I may have jinxed the whole deal by singing the bikes praises too early or by putting the faring on, in any event, I cranked it up and rode it about a half mile down the road and it quit. It acted like it ran out of gas and that was it. I had to push it back to the house. I used to do this a lot with my 250 Triumph back in high school but pushing bikes really sucks when your fat and over 50. I have fire on the front and back cylinders. There is gas sloshing around in the tank but that means nothing. I pulled the tap screw on two carbs and gas comes out but that doesn't necessarily mean it is full of gas. I will have to pull the tank and check the fuel flow next. So much for smooth sailing and riding off into the sunset. (for now).

 

I am almost 87.6% sure that my petcock mod is not the problem but stranger things have happened. In my modification I carefully cut the two diaphragms apart so as not to damage either one. I removed the spring, plastic washer and metal spacer and reassembled everything. In theory, without the spring to force the seal closed there is nothing to keep the valve from not passing fuel. It sounds great in theory but I could be wrong. Who knows what kind of dynamics are now acting on those parts that I have summarily ruined. I may have to take it to bits and gut the thing like a fish!

 

As the bard says "The best laid schemes o' mice an' men Gang aft agley" and so it was with my petcock modification. It seems that either a vacuum or pressure somewhere caused the old rubber to seat, even without the spring behind it. My fix was to install the spring but this time in front of the rubber to keep it from seating. I would have cut the rubber diaphragms as was suggested elsewhere in this site except I was unsure if I could get the two open vacuum pipes to seal.

The suggestion about the side stand was right on the money. After banging the end closed where it had spread and cutting off the rubber retaining cage the side stand now fits neatly out of the way of the shifter.

Now I noticed that the right hand muffler interferes with the axle nut when the swing arm is depressed. I will look into this tomorrow.

 

Just a quick update: I took the FV500F out today and tried to break it. I put about seventy miles on it in town, open roads and back country lanes. I tacked it up to around ten grand quite a bit but spent most of my time cruising around 8000 to 9000 rpm. My impressions are all favorable except the wind is a little gusty today and it blew me around pretty good. It feels like it is running a little rich since It farts and burbles when you turn the gas off. I know I need the balance the carbs. I guess the purchase of carb sticks is in my future.

Oh. . .I also replaced the stock radiator fan thermostat switch with a Four Seasons Part Number 35934 fan switch. I had never heard of a Four Seasons brand anything but that is what my local parts guy had. It is a little bigger around than the stock item and I had to replace the stock spade connectors with round barrel connectors but it fits just fine. The bike runs at 1/3 setting on the temperature gauge and sits right in the middle when the fan kicks in.

The bike is still tatty looking but it runs pretty good.

 

I finally broke down and took my 86, 500 Interceptor to the Honda store to have the carbs balanced. I could tell by the way they were pulling up, just off of idle, that one or more were out of sync. Since I do not have any vacuum gauges I just thought I would let the shop have a crack at it. It cost $97 (same price as a set of gauges) but I think it was worth it. They balanced all the carburetors and now the bike runs wonderfully. It is still noting to look at but it is such a blast to ride. I am a pretty big guy, standing 6’-2” and weighing 260 but this little Interceptor never lacks for zip and it cruises effortlessly at 75 miles an hour. I have not gone any faster(yet) but I am sure it has plenty more on tap. No it is not a torque monster or a house a fire when it comes to power but it is light and the power is just fine. I find the transmission to be an interesting exercise in gear selection. I have been getting off the line and screaming my way through the gears just to do it. I don’t think I have yet made a normal sedate start from a stop sign or red light. I do worry about what I am doing to the clutch since I seem to be dancing on the shifter with a certain regularity. I plan on riding this bike a lot more this summer.

 

Thanks for the updates jim.

 

i have the same exact bike but mine is a 1985 vf500f interceptor payed 500 dollars for it di some work and now i wouldnt trade it for the world found most my parts at partsnmore.com it a great web site and its cheap new parts delivered fast i hope you get it on the road if you haven't already just ask if you need any tips