Where to start with 86' VFR700F that hasnt been touched in over 5 years?

Woody, you are the Man. The front brakes work great now. I assume this method is the reason why they put bleeder valves near the master cylinders on newer bikes?

I'll work on the idle drop procedure over the next few days, and I also hear your advice Crusty. I'm sure I'll be replacing those at some point. I read about those going bad I believe on one of Toe Cutters' carb posts.

I notice also now, and this may or may not have to do with me adjusting the pilot screws or linkages, but at the 2-5k rpm range, if I just hold the throttle in the same spot, it will waver a bit. Would this problem be specific to one of the jets? I havent tested it yet at higher engine speeds.

 

And the brakes feel spongy again today...

Edit: I take it back... temporarily. I remembered that late last night, before I rode today, I needed to adjust the banjo bolt so that the line wasn't bent over the instrument panel and I think that when I did it, I may have opened up the line. So I bled them again tonight and they felt tight again. I'll do a road test tomorrow though to see.

Woody, which DID chain/sprocket set did you get?

 

Definitely double check that you didn't let air in, and sometimes the vibration of riding will help move bubbles up and out, and a bubble in the master may have moved to a more inconvenient place.

For the chain, it was a good, but not top of the line chain (stock 530 size, stock number of links), and IIRC, JTC rear and sun star front sprocket. Or some such. It's been a long while. But they're definitely steel, and seem like good quality. No visible wear at over 5k miles on them.

Using chain wax and trying to keep them clean (I clean the gunk off the rear sprocket when I clean the chain. Front sprocket is a bit hard to get to.

 

Front brakes feel good again so I think that's that.

I did the idle drop and the low end pull is back as well.

 

Bike still leaks a tiny bit of gas a bit on start up. Is this just a sign of dried out carb insulators?

When should I engage the reserve fuel supply? I was happy to see the fuel light works since that popped up tonight.

Another thing of interest was that I noticed there was vapor in the gas tank. Is this uncommon?

My fuel tank petcock also doest close completely in the off position. The last time I removed the tank and set it to off, fuel still dribbled out a little. This was just annoying and maybe its just expected after all these years?

Also, for a valve adjustment, do I need these specific honda Tappet tools? (Adjuster, lock nut wrench, wrench holder)?

 

More likely, that's leaking o-rings on the plastic fuel pipes between the carbs.

That's when I always do it, and then fuel up at the next convenient station.

As in the tank is under pressure, or vapors just waft up and out? It's very likely that the vapor recovery emissions system has been removed in the past. But it could also be a pinched breather/overflow line to the tank.

One dribble, or continues to dribble? One is probably the fuel in the line, continual is a problem, and neither of my '86s have a problem with that.

I don't think you need the specific tools, but it's probably a lot easier with them, given the arrangement. You certainly don't need them to check the valves, and the don't wear quickly, do adjustments are rare. But checking is just good piece of mind.

 

O-rings on the fuel pipes? I don't understand...

I just peaked inside the tank and saw some vapor settling in there. It wasnt pouring out of the fuel cap or anything.

The last time I raised the tank it seemed like it kept slowly pouring out in the off position. I think it was coming from the tank and not just in the line.

I saw another post by Squirrel and he was saying that the parts are unnecessary and that I dont need Honda specific stuff. Just the typical metric tools and feeler gauge.


Some other things...

I just ordered some carb insulators per crusty's recommendation.

The bike still seems to backfire on deceleration (vacuum leak according to one of my motorcycle maintenance books) and it slightly misfires as well.

I noticed the engine wont maintain speed at around the 1800 rpm range and will waver up and down a bit. The misfire is very noticable at this point.

It's getting there!!!

 

So the fuel leak is coming from where the header hooks up to the head. You can see that the bolt holding the header isnt fully attached but should fuel really accumulate in there?

1. Shouldnt the exhaust valve be closed and thus nothing should leak out (sign of bad exhaust seal?)?

2. Wouldn't this also mean that fuel is accumulating in the combustion chamber?

The fuel only leaks from cylinder 2, and I've only tested this from starting the bike on its side stand. Still, its easy to see that the number 2 header bolt is attached all the way.



The second pic is of the fuel vapor I mentioned in my previous post.


Went for a nice long ride tonight since I just got my insurance coverage Is it possible the bike will intermittently NOT shift into 6th, or am I probably just not counting, lol?

 

I'm not sure what's going on there, but my guess is it's leaking, and misfiring while cold, which is why you're seeing fuel there. Once it warms, I assume this all goes away (header seals up and the cylinder starts firing correctly?). Also, is it possible that it's just water vapor and a bit of unburnt fuel mixed in? Mine steams pretty good with condensation out the tailpipes as it first starts up in the mornings.

exhaust valve position is a function of where the camshaft is at with the bike at rest. Without double-checking the timing diagrams, I'd say at any given time at least one exhaust valve will be open because of this.

depends on how much fuel is there. If you have a bad float on that carb, it could be overflowing the float bowl, and running into the cylinder, but I don't know on these if an overflow is external or down the needle tube and the other jets.

no idea on that one. Gasoline vapor *is* heavier than air, so it may just be gas vapors pooling in the tank. OTOH, I've never seen that. What kind of fuel are you using?

I'm always looking for another gear when I get on the freeway. 6000rpm just seems too high for cruising.

By fuel pipes, I meant these plastic T-shaped tubes that fit between the carbs. Extremely brittle, extremely non-replaceable, but prone to leak when the o-rings dry out. My bike does it every time it sits for more than a few months (like after the rainy season, the first start in March or so has it dripping fuel). When I does that, I shut it down, clean up the fuel, and come back the next day. Usually it won't leak after that.

 

Ya, it only leaks for a few seconds initially then stops but I feel like its mostly fuel because of the smell. It doesn't smell diluted, its very rich smelling.

I will tighten the nut and see if that helps. I wonder if that is whats causing the backfire on decelleration? A slight vacuum leak perhaps, since it comes out pretty quick initially.

Was using 87 but went for 91 tonight since I was low and thought, "why not?"

Ya, this makes me think I was already in 6th. It just felt like I was pushing the shifter up against a wall and I read here VFR700F Specs that 60mph top gear is mid 4k rpms so in hindsight, that sounds about where I was at.

After checking the FSM, thats what I thought you meant but I wanted to be sure.

Overall, the bike feels reasonably good. I rode around for 25 miles and that was my longest ever, just cruising around town and on expressway's. At one point I think I smelled the brakes but that went away. Maybe it was someone else's vehicle. I still get some front end shake under hard braking, but luckily, the bike still brakes. There will be lots of kinks to continue to iron out.

Also, uh, how does one shop for new sprockets/chain?

 

What about repairing/replacing hoses? My Radiator-To-Reserve Tank Tube has a crack in it, right near the radiator cap.

 

Just buy new hose, and cut to length.

 

OEM honda hoses or is there a better place to get them?

 

I got the carbs off. It looks a little dirty so far in the float chamber, but nothing seems to be clogging the jets. Im curious about the slow jet though. When looking through the hole from top to bottom, I realize that the cavity is smaller than the outlet hole. Is that how its supposed to be?

Also, when I reinstall them, I just seat them until it resists right?

Also, the float valve seat filter did not come out and is still sitting in the cavity and its not screwed in correct? I just need to figure out some clever way to get it out without damaging it.

And one other thing I noticed was that there was no washer for the float valve seat in the FSM, but there was one in mine as you can see in the pictures.

 

The orifice inside the pilot jet is much smaller than the opening and you will want to take a strand of wire and run through them and verify that they are equally open and clean. The screens will come oot with a little love and a seal pick but they are very fragile, and the sealing washer is normal and required.

 

Got it out Thanks. How do I know if my O-rings are bad?

Also, heres a pic inside intake tubes leading to combustion chamber. Are the walls supposed to be all textured like that?

 

Just more pics and a few questions...



Grime in between the air filter casing and carb #1. Maybe from a leak a while back? Not exactly sure...



The parts on the left have been cleaned... I need smaller wire to get down the middle of the the slow jets but I can still see through all of them..



Whats the tube sticking out from #4, in between 2 and 4? It leaked at some point if you looked closely to the grime at the end.



Another shot at the grime above/underneath #1



Actual carbs, nothing has been cleaned in here as of yet.


So should I just douse everything with carburetor cleaner? I've just been spraying a little on the parts and drying them with paper tools.

The float valve seats have been the dirtiest so far of everythingbut I feel like I haven't seen too much in there that seems to be in the way of any of the holes...

Haven't inspected the vacuum chambers yet...

 

How aboot a pic or two of the slide needles?

 

Springs in the diaphram each seem to be working fine as well as the larger springs in the vacuum areas. Here is some pics. Everything looks pretty good to me. No scoring on the needles, no holes in the diaphrams, springs work, etc.



On the carbs, I did like 2 clean sessions where I sprayed the float bowls with carb cleaner, then air hosed them, wiped out with paper towel, then repeated that process. They look good. Im going to wire clean the jets tonight and then that should do it, I guess? I really feel like I haven't accomplished anything except clean but hopefully this takes care of the fuel leak.

Next up is valve inspection along with inspecting spark plugs since when before I replaced the plugs, the old #2 plug (same cylinder with the gas leak) looked like it came out of a swamp...

I'm also going to toss out some idea, that I dont think really makes sense but for the sake of covering all bases, I'm going to mention it: Is it possible that the #2 plug isn't burning all the fuel? I dont think so because the bike only leaks after it sits for a long period of time. If it didnt burn all of the fuel, it would just leak consistently, which it does not... Argh.

 

From left to right, spark plugs 2 and 1 respectively. Do they look typical? These have atleast 100 miles on them and #2 is the one thats been having the fuel leak.



Again 2 and 1 respectively