Fuel Filters: Are They Needed ?

YesImLDS

Member
Jun 29, 2013
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Columbia, Missouri
Personally I'd have one anyways. Doesn't harm anything and doesn't really get in the way. If you ever pull a fuel filter out of a car they get a bunch of gunk out of the fuel. I would suppose it goes the same for any bike. I use lawn mower fuel filters and they are a few bucks.
 

2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
Even if you've cleaned the fuel tank, like we recommend, there is a possibility that trash can be introduced when filling the tank that can clog your fuel system. The float needle valve is especially susceptible to small particles that can clog it or hold it open. I typically remove the kit supplied filter; the one that is attached to the petcock and use an in-line filter. But that's just personal preference. Some retain it to keep dirt from getting in the petcock.

A separate fuel filter between the tank and the carburetor is good insurance that every motorized bicycle should have. Except those battery powered things. :)

Tom
 

curtisfox

Well-Known Member
Dec 29, 2008
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2 door is right, it don't take much to gum up a carb, cheaper to by filter then rebuild a carb...............Curt
 

MEASURE TWICE

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Jul 13, 2010
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I have a clear plastic filter. The paper inside it is pleated and cone shaped. It has enough area that flow is not impeded. It is nice as it is easy to tell that gas is in the line. Additionally my tank has the fuel outlet raised above the bottom of the tank which possibly keeps some grit from even getting to the filter. But then again I am exclusively trail riding, so I guess it sloshes and may make particle suspension for a while. The tank not looking very nice as it was intended by mfr for a Briggs lawn mower engine, but its plastic and there is no worry of rust. Old lawnmower engines steel tanks I've seen clog the screen that carb was starved of fuel. Back in the days they did not have a filter, just screen.
 

Kioshk

Active Member
Oct 21, 2012
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Connecticut
I'm lazy; I've been running without a filter for about 2-years without any issues. Of course, a piece of crap can wedge in between the float-needle and its seat which could result in a gasoline-puddle. I think the grille in the tank does a pretty good job of keeping stuff from entering the fuel-system.
 

ezrider

Member
May 18, 2016
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Indiana


You would think these kits would come with a decent fuel hose clamp. No biker wants to be seen as a flamin Richard Pryor...in case it does come off.

_
 
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MotoMagz

Well-Known Member
Aug 2, 2010
1,772
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Michigan
Small hose clamp or zip it will hold the fuel line. Lots of people get a smaller size and no clamp is needed..but I always clamp and use a fuel filter. Go to any auto store or Home Depot and get a filter from lawn and garden.
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
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Phoenix,AZ
Never had fuel or air filters ,.been riding ten years this way! No Prob
First 5 years, then 10 years two posts later, here in dirty dusty Arizona?
How many engines did you go through in that 5-10 years?

I am on the other side of the coin, I replace the gas line with automotive gas line and use all the filters I can get because you never know when a Haboob will catch you during Monsoon season which started with one just yesterday.

Come on Flathead, don't encourage people to run no filters just because you are foolish enough not to, they don't cause any performance problems and gas and air filters are their on every gas engine for a reason!
 

MEASURE TWICE

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Jul 13, 2010
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I think I have heard of some gas snow blowers not having air filters on their engines. But in any case I had first hand noticed the benefit of a scored piston and cylinder. This was 50 years ago I was not all worldly. Since it was just bad enough it could start with and easy pull of the recoil starter. Just one thing it had about a 5th the power. I only for test purpose have since in no dusty condition had the air filter off. It help me detect that the foam filter needed to be replaced with a better flowing pleated paper filter that the engine I was mixing an matching thrown out parts required me to change.
 
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KCvale

Well-Known Member
Feb 28, 2010
3,967
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Phoenix,AZ
I think I have heard of some gas snow blowers not having air filters on their engines.
Hehehe, you don't have any dust when blowing snow but I don't know, I never deal the stuff ;-}

What I do deal with this time of year is things like this...




The word "haboob" comes from the Arabic word habb, meaning “wind.”

A haboob is a wall of dust as a result of a microburst or downburst.

The air forced downward is pushed forward by the front of a thunderstorm cell, dragging dust and debris with it, as it travels across the terrain.


Haboobs occur mostly during the summer months in Phoenix but are not necessarily restricted to the monsoon period. These dust storms are much more serious than dust devils.



The wind during a haboob is usually up to about 30 mph and dust can rise high into the air as it blows over the Valley. A haboob can last for up to three hours. It usually arrives suddenly.

This of course has nothing to do with with fuel filters unless you happen to be gassing up, but everything to do with air filters.

Desert Dirt and Gas Engines do not play nice together.
I suggest you keep them away from each other with a big filter ;-}
 

curtisfox

Well-Known Member
Dec 29, 2008
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He ! He ! Ya ! snowblowers have big cover on them, but no filters. They would plug up with fine snow and kill or choke it.
Been in a 2 day dust storm in Montana, Dakotas have them also, and a few other states. Ya filters are a must i even seen the fine screen on my gas can fill up with crud, right from the pump. Who's to know what gets in the tankers when filling.............Curt
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
54
48
Phoenix,AZ
He ! He ! Ya ! snowblowers have big cover on them, but no filters. They would plug up with fine snow and kill or choke it.
Been in a 2 day dust storm in Montana, Dakotas have them also, and a few other states. Ya filters are a must i even seen the fine screen on my gas can fill up with crud, right from the pump. Who's to know what gets in the tankers when filling.............Curt
Exactly my point.
Always prep your machine for local conditions and remember, regardless of your local conditions, dirt in the fuel or air and internal combustion engines simply do not play nice together, and dirt always wins at the cost of the engine.
 

Stealthpony

New Member
Jun 27, 2016
9
0
0
Kingston ontario canada
So I know the filter you speak of I have the same one I believe it is a necessary on a bike..... unless you don't mind cleaning a carburetor now and then and leaving gas puddle when dirt blocks the needle seal.This filter can fail but when redone it is a good filter. The actual Filter part inside separates from the plastic and allows dirt to come through I don't know if they glued it originally or not but it needs to be done.. inside it when you crack it apart along the glue seal it has a small magnet for catching any iron particles if you use the washer after gluing the filter part with some Gorilla Glue it will press on the filter holding it up against the plastic for a better seal and then just reglue the plastic back together with this Gorilla Glue and you have a great filter. This is a picture of my setup I have the line hooked up so that when I run out of fuel I have an actual Reserve when I unhook the line and lower it after fixing the filter I've never had a leak problem again.
 

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Kioshk

Active Member
Oct 21, 2012
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Connecticut
This is a picture of my setup I have the line hooked up so that when I run out of fuel I have an actual Reserve when I unhook the line and lower it after fixing the filter I've never had a leak problem again.
You have a very "interesting" build! ;)

I really like your fuel-reserve solution. How far can you get on the reserve? Since the fuel will siphon until the vacuum's broken in the filter, I would imagine you'd only get a few tablespoons' worth.
 

Stealthpony

New Member
Jun 27, 2016
9
0
0
Kingston ontario canada
Thanks and your right by the picture I noticed that the line isn't very high in comparison to the tank I just had the lines off and put a shorter clear piece on there and ended up bringing it down a bit I will have to raise it up higher to get more reserved. But really I don't know I will have to measure and check sometime normally when she bugs out on me and I see no fuel in the line I pop it off and always can make it home from where I was and fill up. Who originally started with there being too much pressure on the needle valve when the tank was all the way full being so high in relation to the carburetor. I did this to relieve some pressure and it worked and got the reserve as a bonus.