1985 VF500F Carb Issues

Greetings all--
First of all, I want to say how glad I have found this forum! I have been lurking for awhile and am amazed by the level of knowledge here!

Okay, I bought something of a unicorn. A man in Louisville, Ky recently passed away and had a few low mileage motorcycles stored in his warehouse. Long story short, I was able to buy a 1985 VF500F Interceptor with an original 387 miles on it!! Under all of the dust was a very nice bike, but of course, needs carbs, and hydraulics renovated...

So, I got a manual, removed the tank, etc and began work. Put a new battery in and sprayed fuel into the carbs and the bike started right up and actually ran well. I hooked up an external tank with fresh fuel, and the bike ran well but the carbs leaked from the overflows... I removed the carbs per the Clymer manual instructions and tore them apart... The jets were heavily varnished... I carefully and thoroughly cleaned the carbs and jets, replaced the float needles and seats and gaskets and put it back together. Well, the carbs no longer leak, but the bike refuses to run off the carbs... Here's what I know: It will still start right up and run from fuel sprayed into the carbs. There appears to be fuel in the float bowls as, when I remove the float drain, fuel comes out. It won't even cough though unless primed.

I know some form or other of this question has been posted a million times, but I would sincerely appreciate it if you guys threw out some ideas for me to try... I will, of course answer any questions you have....

Thanks in advance for all of your help!
--Scott

 

WOW... Very cool. And Welcome.

And... you only get one chance to post a proper pic in your first post. Shame.

1. Carbs still "dirty". I trust 1% of the population that refer to themselves as "mechanically inclined" to do a proper carb clean on a V4.

B. Get a Honda Factory Service Manual

III. With that mileage, highly likely the Pilot Screws still have the plugs intact. Do you know what I'm referring to?

*Sorry... slightly hung over from the neighbor's Halloween party, so I'm even more curt.

 

Apologies for not including a pic! I will rectify that when I'm done "working." I will hunt a Honda manual online at lunch.... Do you know a source? And, yes, the Pilot Screws still have their plugs in tact... I did not remove...

 

Here’s a pic… slightly cleaned up

 

They MUST be removed (and Pilot Screws removed) to do a proper carb clean.

The other site *cough*VFRD* has a good download section regarding manuals. Ebay has them if you need to get dirty fingers on the the edges of pages.

There's been only a million write-ups and posts regarding a proper V4 carb clean done, but you are not alone or the last to not get it on the first try.

Also, head on over to V4Dreams. Joe has a bunch of great tutorials and write-ups (including V4 carbs) there. Regardless of the year, V4 carbs are all essentially the same process.

You MUST pay attention to details and small parts. Some early carb designs have different jets, emulsion tubes and diaphragm springs for front and rear carbs.

 

Thank you for the reply... I will check those sites out... And, this weekend, I will pull the carbs again (It was so much fun the first time )

 

Jesus Fucking Christ. Look at that Candy Aleutian Blue pop. That bike is {gonna be} sweet. Don't know if you've ever ridden the 500, but the engines are jewels. Keep the oil fresh and the valves adjusted. Don't hang out at redline and above all, enjoy the fuck out of it.

 

A heat gun on low is your friend. And if you know what a radiator hose tool is, they help immensely on getting the rear carbs "started" in the insulators for your final push.

 

Awesome! All your help is MUCH appreciated! I have a number of bikes in the stable, but never ridden a V4 Honda.... Looking forward to it! I have already invested $1593 in general rehab parts including tires, caliper kits, master kits, etc, etc... The tank was gross with rust unfortunately...I was not looking forward to trying to rehab it, but I got lucky... Found a NOS tank on Mercari ... never used allegedly ... I jumped on it

 

One more quick question and I'll leave you alone... Does it surprise you that the bike doesn't even cough from the fuel in the carbs due to not removing/cleaning the pilot screws? I mean, the rest of each carb is clean ... I would've at least expected the bike to cough a little...

 

Not really surprised. You're not cleaning the screws (well, kinda). You're gaining access to the passages behind them so you can spray carb clean and compressed air thru them to verify they are are open.

The passages that are responsible for starting and idling are still plugged, and are critical on those carbs. Varnished fuel is nasty shit.

You need to do some more homework before your next try.

 

Roger that! I have ordered a factory manual, as you suggested and have been doing a lot of reading on the sites you recommended... I don't wanna have to do this 3 times! Thanks again for all the good advice!

 

Hell yes. You'll get it. And it will be glorious when you do.

 

Very nice! Please let us know what kind of money a 387-mile bike goes for so we, I mean I, can feel really bad about what I paid for a bike with 40k on the clock.

 

Hi Sandman. I feel fortunate to have only paid $1000 for the Interceptor. Right place at the right time. That NEVER happens to me. BUT, keep in mind that I have already spent well over that on a new tank, every new seal and hydraulic kit, new battery, etc.

As it looked when I picked her up

 

the best way to make certain an idle jet is fully clear is to pass a steel wire through it. (0.010") soaking and compressed air are only the first steps. or you can buy new ones cheap.

 

Thanks Squirrelman! I will do as you suggest... Here's hoping I have a more successful weekend this weekend than last!

 

another item that needs wire-probing in some cases is the side holes on the mainjet holder tubes.

 

But I assume from your last post and from Capt 80s info, the primary reason the bike won't start and run off the carbs is my lack of removing the pilot screws and probing the idle jets?

 

i think there may be a different reason your 500 won't start, not related to pilot screws or partly-clogged jets.

on any newly-acquired old bike best first step is drain and flush the fuel tank, checking for any signs of rust. next, change all the filters.

does your bike have a fuel pump ?