My neighbor just acquired an OG 85 interceptor (VF700F). Bike sat for 10+ years. As a favor to him , I've been helping him get it up and running. Cleaned tank (full of rust), lines, filter. Jumped pump wires as relay is shot. Cleaned all jets (Incl. drilling out and setting 2 1/2 turns out on pilot jets) with wire/carb cleaner and blew out with air. Intake boots don't leak. Drained and cleaned/replaced all fluids. (oil + filter, radiator, brake/clutch fluids). Replaced infamous broken starter switch. (15.00 on e-bay). New battery. Bike fired right up 1st time. No accel or decel issues. I Have an issue with pilot jets as bike wont die if I turn them in all the way or remove them while it's running. I haven't adjusted valves yet as I don't have a cam holder. However the bike only has 16,500 miles on it and I don't hear any clacking. Motor Purrs. It just wont run without 1/2 a choke. PCV valve works. No vacumn leaks. I didn't bench sync carbs. Waiting on vac gauge from friend. I would appreciate any and all input from VFR members as to what my next course of action should be. I wanna get this thing out of my garage and into the real world. It rides great; got the tires/suspension dialed in and the bike is very fast.
Are the rubber o-rings on the pilot screws in good shape or new? How about the float heights are they set right? I just brought a bike back from 5+years of sitting. He claimed it ran great when he parked it. But after going over everything and double checking it still had what seemed like carb issues. The rpms would hang and the idle was erratic. Turned out the valves were so far out it was causing it. I had two that had no clearance at all and 12 others that were way out. Purrs like a kitten now. I cant see how they could go out of whack from just sitting. But he swears it ran fine before he parked it. I would check them just to rule that out if nothing else. Will be interested to hear what they are. Good luck
taylor65, Thank you for your reply to my post. I took the carbs back out. Soaked in Berrymans for 2 hours each. Blew all ports/orifices out. Re-installed all jets. Inspected choke circuits (good). Pilot jets were clogged. Hence. this is why it only ran on choke. Runs without choke now. But. I get the RPM hang. Not too bad. Bike is fast and has good power through all ranges. # 2 carb/cylinder will not slow down when closing pilot screw. Maybe I need to just replace all pilot jets and see if this helps. Bike sat for a long, long time. I inspected the screws via magnification when I cleaned the carbs. Bench synced the unit and went through the pain of re-installing the rack. I found that using a 2 x 4 under the neck of frame and a block on the plenum, exerting gentle pressure worked good with the help of my neighbor. Doing this alone is a lesson in futility. Does the lack of RPM loss in #2 due to a clogged pilot circuit? Maybe I should adjust the valves as well. I understand your bikes RPM's hanged until you adjusted valves. This bike has 16,000 miles. Bike starts 1st time, every time. Any advice would be greatly accepted/appreciated. Thanks in advance. Still crazy.......
Oh, also. The O-rings on pilot screws are not new but seem to fit tight on screws. This may be an additional problem, no?
The bike i recently worked on had only 19,000 miles and was/is a one owner bike. I had two valves so bad i couldnt get the smallest feeler gauge in. Which was causing two valves to never close completely and in turn the reason for the rpm hang. Rpm hang is almost always from a to lean condition. That is good that you have it running a lot better but if you made sure that all your pilot jets were clean in that you could see light through them then i would say your pilot jets are fine. If i were you i would double check all your work making sure there is no way air can be leaking past your carbs. It can get past your intake boots the manifold o-rings the fuel screw o-rings. I would just check it all over again for anything suspect oh and make sure all your fuel screws are set the same. If you are not getting any improvement then i would check your valves. Its very easy to check them and then if thats not it at least you have checked them. Which needs to be done anyway. I never adjusted my 83 so i cant tell you what all is involved but after doing all that carb work yourself im sure you could handle it. Keep us updated
Also, sounds as though your o*rings on the fuel screws are fine. They should fit on kinda tight. A trick for cleaning those pilot jets is to run a thin piece of wire through them several times along with the carb cleaner and they should be fine. But im still betting on the valve check/adjust being the problem. I could be wrong as you may have an air leak somewhere but it sounds just like what i went through. Good luck
Thanks taylor65 for response. Checked valves today. All were tight except 2. I did not use a cam holder on the valves but did the rest by the book per jap manual. Now, the revs are still high! Tappets are now a tad louder. Thank u in advance for any and all help. 2 heads are better than one. Regards.
If the valves are checked/adjusted and the revs are still hanging you must have an air leak somewhere causing a lean condition. Just to double check, when you rev the bike up to say 6 or 7 thousand rpm and let off the gas the rpms slowly come back down and then stay high? Regardless of where you set the idle? If so then somewhere isnt sealing off. Have you done a compression check?
No leaks. Revs come down slow. Not a REALhang. I think it's a pilot circuit. I ordered new pilot jets (stock) and will blow out passages again on each carb before installing new jets. Will replace O-rings on pilot screws also. #2 is definitely clogged/lean as plug color indicates. #2 pilot screw does not adjust RPM's. I adjusted valves. However, I did not try the Dave Dodge method. I will next time. Went to redo valve adjustment and one of the rocker arms on intake side of #1 broke at the adjuster. I hear this is not uncommon. Will keep you informed of my progress after expensive (about 40 bucks in Calif.) acquisition/reinstallation of rocker arm/valve adjustment/compression check. I'm getting an education/observation on cam assembly. Some slight scoring, but nothing real bad. Lobes are within factory specs. Cam journals look good. Chain/tensioner/sprockets in good unstretched shape. I doubt I'll do any oiling mods at this point. Bike has 16,000 miles. BTW any idea where the vacuum line from bottom of pcv valve to engine goes? Factory illustration/tank sticker is not specific in the drawing provided. This is a Calif. model. I will plug all off after inspection if this will not affect performance. Any and all help is appreciated............ Regards
