Hey all. My Pilot, which has run excellent the past 5 years I've owned it, recently started backfiring at full throttle. This happens after it gets good and hot. When I first ride it for about 20 minutes its perfectly fine, but after that when I give it full throttle it will randomly backfire and it loses power each time it backfires for that split second. It is still running fine but I will be parking it until I've figured out this mystery. Any help where to start looking to track this down is greatly appreciated.

Is it backfiring through the carburetor or is it just popping loudly out of the exhaust?

If through the carb; check reeds and jetting.

If through the exhaust; check for leaks, seal ALL leaky points, and check your jetting.


Are you getting any ignition break up? What does the plug look like. Any ignition weakness could be cutting fire at full throttle which may be causing the exhaust based backfire.

------ been there ------ low fuel flow (check pump) or air leak.
CO

Is the idle faster than normal?

among all the other stuff suggested - take a close look at the base gasket. Could it have blown out?

Classic sign of blocked fuel filter at highest demand fuel flow at WOT (Wide Open Throttle).Mine was great at idle jet thru to needle jet but when on the main jet it couldn't allow enough fuel thru was running on the carb bowl till it emptied.Reverse blow filter into a white container and see all the peppery crap that was responsible for the blocking.Mine did the backfiring too.
Once cleaned out no more backfiring and fuel bowl remains filled at WOT (Wide Open Throttle).

Thank you for all the suggestions. I have not ridden it personally but when we were on the beach I was riding along side of it and it I could hear it randomly pop through what appeared to be the carburetor. This only happens when its good and warmed up. I am going to try a new fuel filter first. The one on it is after market and I have a few OEM brand new filters to try. I will try to do this today,

Side note; I clicked the Notify me if anyone replies tab but I did not receive any notifications through email

I receive notifications, do you have a spam filter, they could be getting caught there?

I would be doing a flow test before I even drive that thing again. JMO.
CO

Found the replies in junk folder. Thanks everyone

I swapped out the filter and all appears well now. The filter I took off was plugged pretty good. I could barely blow through it. The replacement filter I could easily blow through. Is there any way to clean the old filter for use another day? I thought I had spare filters but they are apparently for old FL350's I used to own. Or does anyone know where I can buy FL400 fuel filters? Thanks for all of your help!!!!!! The filter I have is 16900-heo-003

I would also be checking the fuel tank pick up lines.
Verify you don't have a rusted up tank and lines.
That garbage in the fuel filter came from somewhere. JMO.
CO

Thanks. I'm sure there's some stuff in the tank. It's been 5 years since I last replaced the filter. I was looking on Ebay and people who have nos filters want over a hundred bucks for them. I'm not a player at that price. I just ride my stuff. No trailer queens here

Love it !.
CO



Apparently others here have blown backwards through the filter and were successful so it wouldn't hurt to try that. You would have to regulated down any air pressure or you'll destroy the guts.
Whats wrong with using some after market filter that's just close ??
CO

I've searched the forums and haven't found anything anyone's used except for a straight inline filter. I like the way the factory mounted it

I thought zero client found one that fit in the OE holder and was relatively close to the original.

From: Zero post
Thanks. Rppjr

Post subject: Re: Dave-Co PilotPostPosted: Thu Dec 19, 2019 2:56 pm
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Joined: Fri Jul 04, 2014 7:33 am
Posts: 987
Fuel flow rate FAILED at 3oz/10 seconds. Out came the seat. Drained the fuel out the the fuel tank. System is using factory on-off valves and an OE style fuel pump and filter.

I disassembled the OE Keihin fuel pump but it was clean as could be. There was some stuff in the tank that is now drained and cleaned out. The OE fuel filter was actually quite difficult to 'blow' through and so I came up with an AWSOME solution! Went to my local Auto Parts store and located a suitable HIGH FLOW, REAL replacement. This is not a plastic pos lawnmower filter. The item/filter is a FRAM 33293, which may also be a Micro Guard or WIX filter (FRAM G7092 or PTC PG7092 also on the box). This is a FUEL INJECTION filter for a small car, but the in-store blow-through test yields a very surprisingly non-restrictive fuel filter. AND it has 5/16" mail ends which easily connect to fuel lines; AND it fits the factory rubber holder.

Observe photo:

Thank You!!!!!!!!!