News:

           Enjoy your FJ


Main Menu

Air Lock and Idle Question on 86

Started by Mike324, September 13, 2020, 07:01:34 AM

Previous topic - Next topic

Mike324

Hello fellow owners,
Finally got my new RPM petcock installed and the bike insured and plated. Have been only starting the bike and riding in driveway since I bought it last fall. I was expecting it to run a bit rough, but it ran great. I rode it for half and hour slowly getting used to riding position etc., gassed up, and drove another half hour on some country roads. Pure joy! When parked at home I could hear the whistling sound from the tank that is familiar to many.

The next day I promised my wife a good coffee and took her for a slow ride, 3,000 - 4,000 rpm max. As we got close to the cafe destination, only ten minutes from home, the bike began sputtering and then came to a stop as if running out of gas. Fuel read almost full. I tried reserve position just in case I had a petcock problem and no luck. I then opened up the gas cap, as I have had to do on my 80 Gold Wing several times before, and the FJ started right up and within two minutes was running great again. Did I experience an air lock? I have looked on the forum for solutions to the gas cap venting problem. Seems the seal may need replacing or removal if I am reading correctly?
Thanks for any suggestions, Mike

86 Yamaha FJ1200
80 Yamaha XS1100G
74 Yamaha TX750A
73 Yamaha TX650
80 Honda GL1100 Vetterized with Terraplane sidecar

Waiex191

Mike,
My '89 has a vent line that comes from a fitting at the back of the tank. Is yours pinched or anything?  Or does the '86 not have that setup?
Bryan
1989 FJ1200
1981 Suzuki GN400
Poplar Grove, IL
 

Pat Conlon

Bryan, that fitting at the back of the tank is a drain line for any fluid that builds up in your recessed gas cap. All 1986-1995 FJs with the recessed gas caps have this drain.

Mike, is your fuel line routed correctly?  http://www.fjowners.com/index.php?topic=18286.0
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Mike324

Thank you for your responses. Yes I was quite careful when installing the new petcock to make sure the lines were in the right place. I did have a look at that link before. I will check again to make sure. Is the whistling sound something that needs to be corrected or can it be left I wonder?

The idle question can wait until I have more time in the saddle. It just seemed a bit fast when I got home...1500.

Thanks, Mike
86 Yamaha FJ1200
80 Yamaha XS1100G
74 Yamaha TX750A
73 Yamaha TX650
80 Honda GL1100 Vetterized with Terraplane sidecar

Pat Conlon

Mike, do you have a Calif. model FJ?
When folks alter the vapor control system on the Calif. models, strange things happen to the fuel tank venting.

FYI Here are some pictures showing the cap assembly and the flapper valves we take out for venting.

http://www.fjowners.com/index.php?topic=2024.0

Hint: When you take the cap apart do it in your bathtub bucket. The drain is the first place the ball will go.... [edit by the Monkey] ....you crazy monkey, you don't leave the drain open [edit by Pat]
Why?
There is a tiny steel ball (the key flap detent ball) that is under spring pressure and when you pull the cap apart, that little bastard flies out with amazing velocity, always in a unknown direction...ending up captured by some kind of rift in the space/time continuum.

If you search thru the forum with the term "Flapectomy" you will find many posts from folks who have had the same thing happen to them as you did with the bike stalling.

Re: Idle. 1) Adjust valves, then 2) Sync the carbs....then work on your final tune.
Here is a good write up from Factory Pro to review. Look at Section 4

http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html


Cheers
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Mike324

Thanks Pat for links. I will read them with interest. I have what I believe is the Canadian import. It was sold new in Canada and has the Lateral not Perimeter term in script. Really enjoyed my first two rides this past weekend, with the exception of that brief sideline. Love the riding position and seat, not to mention the fabulous torque! Mike
86 Yamaha FJ1200
80 Yamaha XS1100G
74 Yamaha TX750A
73 Yamaha TX650
80 Honda GL1100 Vetterized with Terraplane sidecar

Pat Conlon

1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

5speed

I'm experiencing the same issue with my 86. the previous owner warned be about it. His solution was to pull over and open the gas cap.
I want to do a proper fix.
I read the pdf file but it didn't explain what to do to fix this issue.
Does the gas cap just need a good cleaning internally or is there a modification that needs to be done?
1986 FJ1200
2000 Roadstar
1976 GL1000
1978 GL1000
1982 GL1100 (sold)

RPM - Robert

http://www.fjowners.com/index.php?topic=2024.0

Open the pdf it has all the pictures you need. Remove the orange and white(yellowish white) piece and throw it in the trash.

FJmonkey

And pay close attention to the white plastic part the orange/brown flaps are mounted on. If you put that part back in, backwards you will still have no venting. Randy found this on my 86' when I was still having fuel issues at a rally. Flipped it over the right way, all was good. Kookalooo.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

5speed

many thanks. I wasn't going to even plate and insure the fj this summer as I have 2 other bikes on the go as projects but darn...every time I go in the garage...lol
1986 FJ1200
2000 Roadstar
1976 GL1000
1978 GL1000
1982 GL1100 (sold)

5speed

1986 FJ1200
2000 Roadstar
1976 GL1000
1978 GL1000
1982 GL1100 (sold)