*& 700 starting with no choke

1987 vfr700f2 wierd ..start everytime without choke ,,all choke plungers are al in ..just ran it till it hit res at 135 mi.pretty average mileage ,all plug but one look great one is slightly rich..but not black rich...now my 86 vfr700 needs the choke to start..if a main jet fell out would that let her start without choke? beats me never seena honda start with no choke ..all mixture screws are out 1.5 turns......what say u ?

 

its a 1987 vfr700f2

couldnt edit title .

 

Mixture screws seem a little lean. If I remember correctly, when I redid mine, I'm around 2 or just a tad over 2 turns on each. That being said, I never did the proper idle drop procedure, so I need to do that before too long.

I always thought my mileage seemed a little low, but my reserve light always came on right at or around 135 miles too. Good to hear that I'm on par with where it should be.

Hopefully, someone else can chime in and offer some assistance. Are you certain that all enrichment plungers are in all the way on all the carbs? I ask because I had one that was stuck out a little bit when the others would be closed... had to actually remove the plungers to find a tiny piece of plastic stuck inside the bore keeping the plunger from seating all the way. I also found that the throttle would not close all the way when I first got the bike. Ended up being that there was a small shard of wood (wtf?) stuck in one of the carbs keeping a butterfly valve open partway. It managed to bend that butterfly plate, so I had to remove it, straighten it, and put it all back together.

Anyway you slice it, once you've pulled the carbs once or twice, you realize that it's not a real pain to do. Might be worth pulling them and going over them with a fine tooth comb to ensure all the linkages are lined up and working properly.

 

well pulling the carbs aint no big deal,,when i synced em only one carb needed adj ..i pulled the tank and checked the choke linkages everything is seated ,,guess ill pull the carbs again and double check the jets..

and the damn thing still has a ticking in it at highway speed .ticks right along with the revs u give it..and stethascope says its in the primary checked the starter clutch its ok.no cracks rollers perfect .didnt pull the clutch .rechecked the valves.,,only does it after it warms up..but hey at 135miles to resv im happy with that..just ticking with 9400mi on it drives me nuts..and gas at 4 bucks a gal ..17$ to fill up the 87 700 with hi octane today ouch..happy riding its 80 deg here today..gregg in ohio

 

What's your idle speed?

i'm guessing your idle adjustment screw is turned in so much that the throttle valves (butterfly valves) are cracked open, which lets the carbs run on the transistion ports instead of the mixture port. This would explain how you can start the bike without using the "choke" because you are pulling excess fuel thru the trans ports that would normally come from the "choke" circuit.

The butterfly should be closed at idle and there should be a slight amount of free play in the throttle cable/twist grip such that when you let off the grip it slams the throttle valves shut. Try backing off the idle screw to close the butterflys and then opening the mixture screws slightly to adjust the idle speed.

This will improve your fuel mileage also since you are pulling excessive fuel when idling on the transition circuit vs the proper idle circuit. i'm getting about 190 to reserve.

Damn the rangers just beat redwings in ot...

 

You should be putting in 87 octane, you are getting no benefit from running higher unless you do not want to run gasahol.
I get about 130 to reserve on regular 87 no gasahol, around 120 with gasahol. In Ohio your mixture screws should be 2 turns out.

 

well i set the mixture screw 2.5 turns out and the idle went up and had to adjust the idle down with the knob..ur correct i was to lean on the mixture screws ..dont know what i was thinking when i had em off and adjusted them..sounds better also..took it for a run and didnt really hear the ticking at speed after warm up it could had detonation from the mixture air screws being in so far on the lean side..time will tell..gregg in ohio

 

I am having the same issue with my 86 750cc. The bike wants to die when it is just sitting at an idle and when I pulled the plugs a couple of days ago one was actually wet with fuel. Where are the mixture and idle screws? Are these on the carb directly? or somewhere where they can be accessed without taking the tank off? Pictures would be great.

 

^^ Dies with choke on or off ??

Wet plug suggests possible leaky float needle, but you need to check spark too.

Best proceedure is to address problems one at a time, not just start turning screws......

 

Dies with the choke off. I just replaced the spark plugs and it runs great when the throttle is open. The carbs were also just replaced a couple of weeks ago.

 

carbs "replaced" but were they clean ??

 

Excuse me...they were rebuilt...so I assume they cleaned them in that process. If they did not they are some crappy mechanics. (also this work was done before I bought the bike so details are tough to come by)

 

If a mechanic says he's gonna "rebuild the carbs", it tells me that he doesn't really know what he's doing or he's trying to get more money out of the job. Like auto mechanics that tell chicks they need to have a bunch of stuff "rebuilt" just because the girl don't know squat about cars.

Dirty or clogged carbs need to be "cleaned" and any broken, worn or damaged parts need to be "replaced".

And "cleaning" involves more than just spraying the outside of the carbs with some miracle-in-a-can carb cleaner and declaring the job done.

Anybody who has "rebuilt" a set of carbs should be able to tell you exactly what they found and how and what they did to correct it, the size of all the jets and needles, and the setting of all the screws. Anything less is BS down here in the land of the squidbilly...