Carb work 1985 vf700f Brand new to the website here though I've come countless times to read up on info. I'm rebuilding an '85 vf700f. It is ny first rebuild. I'm now to the point where I have rebuild the heads and have the bike assembled. Here's my dilema. For some reason my two carbs from my front head are spitting smoke back up. I've heard this may have something to do with the fuel to air ratio and am wondering how to adjust that or if there may be something else wrong entirely. Thanks in advance!
There should be a mixture screw on the body of each carb to adjust the A:F Ratio. Beyond that there are a lot of carburetor gurus on this site, one of them is bound to know what's up.
Elonejd, welcome to the forum! We would all love for you to post in the introductions forum and give us a pic or two of this cool project! Please be careful, okay friend? Excess gas, with your face right there, and it flashes, that is what I am worried about. I plead ignorant to hands-on as I haven't had a carb since a Quadrajunk on my 1980 Delta 88. So with that distinction I will throw in some guesses. First a clarification: You said "smoke" but it is excess gas fumes, right? AKA gas evaporating from heat, rather than black combustion smoke coming out? General possibilities: * Mixture, mentioned by RR is one source of excess gas. * Second, if the floats are not working correctly the bowl may overfill and dump in the gas. Can you observe the bowls during operation? * Three the choke is overly rich and you see the problem go away when the the choke is shutoff and the gas is burned off. The fuel pump is stock spec right? I am just covering the possibility of excess pressure. Finally, I yield to all the guys who actually do this unlike me.
There's a chance that the valves aren't seating properly or running with too little clearance or improperly timed. Any of that can cause your problem.
Thanks for all the responses! I've checked the timing multiple multiple times against the manual. I've adjusted the fuel/air ratio pins without the air box on it to moniter the carbs. Got it running to the point of driving it down the road for a test drive. Problem is now I've put the box back on it and it wont run again. Checked the filter and it's a bit dirty so I'll be getting a new one. Tried again with just the box on and not the filter thinking that may've helped. Still can't get it to run. Messed with the ratio again (I took note of where they all were when it was running) and it still wont work. Almost like it's choking itself out, and there's nothing in the box to restrict it other than the box itself.
A dirty air filter can wreak havoc on an otherwise well-tuned bike. As far as the fuel mixture screws go though, I believe 2-1/2 turns out from seated is the factory mixture setting. Always a good baseline to go off of, then just figure for your mods.
The Front Cylinders run off One CDI box/1 Coil. Check the CDI box/Coil Connectors/Spark Wires,,.. Resolder the 5 Wire Posts in the CDI box.
