1990 Fatboy Carb. Issue
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Stage II
Joined: Apr 2010
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1990 Fatboy Carb. Issue
1990 Fatboy. Started and ran great. Pulled it into storage last summer, two weeks later went to take it for a ride. This is happening to this day... Full choke to half choke, starts and runs great. Twist the throttle, cuts out. Choke closed, cuts out and dies. Vacuum piston rises freely by hand, but jumps around and does not rise when giving throttle. Checked diaphram, spring and seat. those are good. Cleaned entire carburetor. Checked vents, changed gas caps. Checked V.O.E.S. got whacky readings so replaced. Been a long winter and want to ride, any thoughts or suggestions would be greatly appreciated. Thanks in advance.
Outstanding HDF Member
Joined: Jun 2008
Posts: 2,374
Likes: 5
From: redbank new Jersey
The carb on that bike is 20 years old ......It sounds like you really like your bike myself I love the 90s EVOs ...Maybe look into a new 42mm mikuni your bike will run better then new. Sometimes its just time for an upgrade.. They run about 260 new
Cruiser
Joined: Apr 2007
Posts: 206
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From:
I had the 42mm mikuni on my '97 Fatty, and ran great, but it was a pig on gas.
Road Master
Joined: May 2009
Posts: 1,232
Likes: 8
From: Powder Springs, GA
While you are checking the fuel valve flush that tank out all the way and put fresh high test in it. Rule out bad gas before you waste money. Or put some seafoam in there.
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Outstanding HDF Member
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From: redbank new Jersey
that should not change anything..
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Stage II
Joined: Apr 2010
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The Petcock was replace 1 1/2 yrs ago. I pulled it and cleaned it Two weeks ago. Nothing on it. I recoated the inside of tanks 15 yrs ago and never had a problem till now. Drained gas and nothing floating around. Without upgrading to a new carb I may try rebuilding it. Has not been done for 15+ yrs. I thank you all for the help, this one has been kinda baffling. Great rides by the way, I espescially like the '03 Softail above. Would love to get a new one like it and keep this one for nostalgic reasons, but not in the cards now.
Road Master
Joined: May 2009
Posts: 1,232
Likes: 8
From: Powder Springs, GA
The Petcock was replace 1 1/2 yrs ago. I pulled it and cleaned it Two weeks ago. Nothing on it. I recoated the inside of tanks 15 yrs ago and never had a problem till now. Drained gas and nothing floating around. Without upgrading to a new carb I may try rebuilding it. Has not been done for 15+ yrs. I thank you all for the help, this one has been kinda baffling. Great rides by the way, I espescially like the '03 Softail above. Would love to get a new one like it and keep this one for nostalgic reasons, but not in the cards now.