1987 VFR700F2 Won't Start - Posible Spark Generator Issue

That for sure is the pile of parts that comes off an 86 VFR. The great thing is you get a bunch of good quality OEM vacuum and fuel tubing (with clips) to use for this project and others.

On a buddy's bike, I cut the metal tubes coming off of the front head with enough left to double fold and crimp to seal. Supposed to be temporary to be made pretty by him later. They are still like that now with zero issues. On mine I cut them flush and JB welded some nice allen head bolts in there for appearance.

On another one I did for somebody, I left the tubes intact until they come to the pump, cut the longer one off and just looped it back on the other one. Still like that today with zero issues (also left for them to make it as pretty as they wanted). Pretty sure there was a remaining tab that still allowed it to be bolted near the right front coil?

Fuel tank: I ran the vent to a small battery acid catch tank that could still be vented. I had a feeling if the vent was routed to the bottom of the bike it might create a vacuum from the air going over the end and help "pull" some sloshed fuel out. I tried it that way and I got a little gas in the catch tank. When I routed the vent out of the wind, no gas. I wanted a catch tank because I didn't want any fuel dribbling and/or atomizing on my stuff if it did find it's way out. California cap is fine as long as your tank is vented properly.

 

Yellow and red for sure capped. Any angled spigot that comes off of the carbs in that location needs to be capped or connected to another one. Blue I can't remember off of the top of my head. I'm not even sure if it actually does anything.

 

Okay, believe it or not it worked. I removed the cap from the air tube (yellow arrow) and success!!! Thanks again for hanging in there with me. You never know what you'll find when you buy a non-running motorcycle.

[video]https://youtu.be/Zk2sA951xF0[/video]

 

The yellow one is the vent for the float bowl. So I think your wrong on that one.

I would just add a little section of hose to that yellow vent and angle it downward. That way there's no chance of water ever dripping down on it and getting in the carbs. A little pod filter is okay as well. It will keep the bugs out.

The blue and red arrows must be unique to cali carbs because I don't remember seeing those on my bike.

Glad it's working now. The fuel pump is probably fine, but I'd still inspect the contacts and maybe clean them as it free and easy.

 

Yep...The fuel pump contacts are on the list of things to check. I took Captain's advice and added a short length of tubing and ordered a Uni Filter that will go on the end of it. It sounded like a good idea. I just got done syncing the carbs and they needed very minor adjusting.

Now I'd like to try the drop idle procedure on the air fuel mix screws (Pilot screw) but I'll need to wait for a day when I'm in a great mood. I've never been able to do that procedure correctly on bikes with more than 2 cylinders. Wish me luck...Thanks again!

 

You don't need to do the drop idle procedure. Just set them 2 or 2.5 turns out and ride the bike. I tried several different settings and kept a text file on my phone with all the details.

I believe 2.5 is about stock.
3 turns out made it slow to return to idle, it smelt rich plus the fuel mileage suffered.

If you go less than 2 turns check the plugs to make sure it's not too lean.

Right now, mine is 2 turns out, I get the fuel light at about 120 miles, I have to switch to reserve at 125-127 miles. If I fill up at 125 miles I add 4.2 gallons so I get 29.7 mpg.

I don't ride a whole lot, so it's easy for me to keep notes.

If your filter is paper and the air box is stock, then you might have a weak spot in the 5-6k rpm range with your free flowing exhaust. The cure is to raise the needles with one or two tiny washers.

If you run a k&n filter or modify the air box for better flow, then you'll need to swap in larger main jets. Or drill the stock jets bigger.

That's the general tuning guide for these bikes and I'm sure the others will agree.

Now you just need to do anything else to get it on the road. Have you replaced all the brake and clutch fluids? New fuel filter? I tend to toss a few small magnets in the gas tank to collect any rust particles that float around. Make sure the charging system is putting out good voltage. Check the connector for the 3 yellow stator wires. Check and clean as many electrical connectors as you can. The ignition switches sometimes need cleaning. It's easy to remove and take apart. Clean the contacts, remove the old grease and add fresh dialectric grease to it and the key will click properly every time and give good voltage to the rest of the bike. Pull the parking light fuse so it won't run the battery down. That's the usual stuff.

 

As long as the common vents (the pipes with o-rings) are not plugged or routed wrong, the small angled spigots do not need to be open as well. Is your common float bowls vent un-plugged now?

I know that I do not run small vent tubes to the atmosphere. It's been about a year since I did my last one and I'll double check my set-up, but I'm pretty sure I connected the vacuum spigots on the left front and left rear carbs together and connected the vent spigots together on the left rear and right rear carb.

I just wanted to make sure you have the large common vents unplugged. You can still vent with the smaller ones, but I wouldn't eliminate the large ones.

 

Right now they are set at 2 turn out. I need to just ride the bike to see how she feels. The filter is stock from EMGO. There is a Yoshimura muffler on it. Other than that it's stock with the CA smog removed. I've only replaced the engine oil (with Honda oil), air filter, oil filter, and antifreeze (again with Honda antifreeze). Next are tires, brake and clutch fluid, and repair and paint the plastic. Then it might be for sale so I can find an RC51 ;0)

Captain, the ports on the carbs are plugged but the large air pipe is now open. That was the problem keeping it from starting. Once i removed the cap... it started right up. I've ordered a small filter so the air pipe is filtered air vs wide open.

 

Awesome! If you have to go more than 2-3/4 on the pilot screws, then you need bigger pilot jets. BUT, even stock bikes can benefit from going up a size on the pilot jets, they are lean from the factory. With your slip-on pipe, if the carbs ever have to come out again, definitely increase your pilot jet.

 

Shoulda mentioned you had a Yosh earlier as that WILL require mid-range tuning with washers or mainjets to avoid a natural flat spot area. :stung:

 

I saw his exhaust in his youtube video. Have you seen his bike? It's like factory fresh and so clean. I'm jealous. There's not even any scratches around the ignition switch where keys always rub. Water tank is all white and clean. Carbs are all shiny. Makes my bike look like crap. Lol

It must be that dry California air compared to the high humidity we get around Houston. Plus my bike was probably left outside a lot by previous owners.

 

Thanks Squirrelman. Good advice. I gotta tell ya I took the bike for about a mile ride yesterday between rain storms, and it runs great. If there's a flat spot, I didn't notice one. I've never ridden a Honda V-4 before...Impressive. I might have to find a VFR1000!

Thanks Jason. It is pretty clean, but wait until you see it with all the plastic parts. It's got road rash and a lot of cracked broken pieces. Most of my work now will be spent on body work and paint plus that ugly seat! It usually is dry in Sacramento but it's been raining a lot this year.

 

I think we'd all like a vfr1000, but honda never made one. Both the newer vfr1200 and older vf1000 use different engine designs and just don't sound as good.

 

LOL...You're right... Missed it by one letter. VF1000R ;0)

 

Ask Captain 80s about those bikes. My understanding is that they are old 1st gen designs and not much faster than the 2nd Gen vfr models. Plus the old 360° cranks just don't sound very good to me. I wouldn't swap my vfr700 for one.

Maybe Captain 80s can compare them since he has both models.

 

I own 3 1000s, an F and two Rs. While I love them dearly and thoroughly enjoy riding them, a second gen is a far better machine. Comfortable, good handling, reasonably light, reasonably fast. And that sound. I have upgraded to F2 suspension and wheels on one of my 700s. It is now a ridiculously capable machine.

 

TC has had years and years of VFR 'sperience, and he's never been wrong yet.

:beguiled:


On '86 and '87 VFRs there were tabs on the idle mixture screws to prevent "tampering" or defeating EPA rules. Float bowls had a matching tab that stopped screw, but due to geometrical factors, the float bowls should be swapped around into positions to unlock the mixture screws, never mind how it came from friggin Japan.

If necessary, tabs on float bowls can be filed off easily, but DON'T ever remove tabs from the mixture screws as they make adjustments easier.

 

"You don't need to do the drop idle procedure. Just set them 2 or 2.5 turns out and ride the bike.

I believe 2.5 is about stock."


But that's not scientific enough and a bit lazy. Why ignore the Honda service manual ? In theory, each mixture screw can be optimized to its cylinder by accurate adjustment and some road tuning, either by ear and judgement or using a A/F meter for a precise, digital ratio readout somewhere within the stokie range.

 

"F2 wheels?" What's the difference from F?

 

Talking CBR600F2 (1991 to 1994). Wider and can take modern radials. 3.5 x 17 front and 4.5 x 17 rear.
http://vfrworld.com/forums/showthread.php/47444-1986-VFR-Track-Bike-out-of-parts