For those of you who run inline fuel filters

HondaMan

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Re: For those of you who run inline fuel filters

« Reply #1 on: March 25, , 07:08:04 PM » Check also:

Gas cap vent for rust & corrosion.
Float bowl vent holes: these are tiny little holes above the float bowl, in the carb bodies, that go to the little vent tubes that join the pairs of carbs together  They corrode inside sometimes, and won't let the bowls breathe.
Kinks in the hoses.
Fuel line routing: the hose(s) should route always downward or horizontally, never upward.
See SOHC4shop.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
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Link to website: SOHC4shop.com  (Note: no longer at www.SOHC4shop.com, moved off WWW. in ).

Spanner 1

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Re: For those of you who run inline fuel filters

« Reply #2 on: March 25, , 07:09:46 PM » Oh man, there has been lots of posts about in-line filters...they have been blamed for everything from global warming to ,,,fill-in-the-blank....
The consensus is that they are more trouble etc., etc., i.e. the filter ( clean ) above the petcock does the job, but hold on for more opinions...................... If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

heffay

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Re: For those of you who run inline fuel filters

« Reply #3 on: March 25, , 07:15:40 PM » if it is the proper filter... it does not restrict flow, it filters foreign matter. Today: '73 cb350f, '96 Ducati 900 Supersport
Past Rides: '72 tc125, '94 cbr600f2, '76 rd400, '89 ex500, '93 KTM-125exc, '92 zx7r, '93 Banshee, '83 ATC250R, 77/75 cb400f

nokrome

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Re: For those of you who run inline fuel filters

« Reply #7 on: March 25, , 08:04:12 PM » +1 on the gas cap vent hole...... my k2 had those same symptoms when i first got it ..... took me a couple weeks to figure it out because i was such a newb........drove me effin crazy Funny thing about regret is...... its better to regret something you have done than to regret something you haven't done.

mystic_1

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Re: For those of you who run inline fuel filters

« Reply #8 on: March 25, , 08:21:50 PM » Problem is your routing.  With the way your hose is run, the gas flows down out of the tank, then has to turn a 180 and flow uphill for a long distance before going back down to the carbs.  Fuel delivery is gravity fed, liquids don't like to flow uphill.

Instead, come down out of the petcock, through the hole that should be in your carb mounting plate, then to the tee fitting and from there into the carb inlets.  Try to keep the flow going downhill the whole way.

mystic_1 "A ship in harbor is safe, but that is not what ships are built for."
- John Augustus Shedd

My build thread:  http://forums.sohc4.net/index.php?topic=.0

Hush

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Re: For those of you who run inline fuel filters

« Reply #14 on: March 25, , 11:28:36 PM » Something "ate" my in-tank filter so when I switch to reserve all the sand in the Arab empire and rusticals off the Titanic race to be first to block my carbs!
The tank is spotless inside so they also have magic transporter powers.
Have a very very small disposable in-line filter fitted and it's cheap insurance but as the guys said you gotta keep the flow downhill.

More of a question is, why did Honda make the main tank only able to extract the top half?
My petrol "straw" is like 3 inches long, it takes all my willpower not to slice 2 inches off it everytime I have to remove the gas tap. I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Buber

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Re: For those of you who run inline fuel filters

« Reply #15 on: March 25, , 11:56:54 PM » So you say that filter is not needed? Others say cheap insurance? I will tell you my short story:
I'm on way back home from decent trip ( kms), and 120kms before the end I can feel that gas it getting loose. "aha, those old gas cables are giving way" methinks, and me's right. A moment later pulling cable is gone. So, short stop, TANK OUT, DISCONNECT FUEL LINE, fix the cables (little trick) FUEL LINE BACK, and going home. Some 50kms later i notice that my carbs  are overflowing.

To cut the story short - in the course of moving the tank in/out of the bike, a small bit of rubber from the hose went down the hose and blocked one of the float valves. Next thing I did home, was to fit a in-line filter. And don't tell me it's not needed. It was.

My 2 cents... Welcome to my mountains!
Mountain Chalets

TwoTired

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Re: For those of you who run inline fuel filters

« Reply #16 on: March 26, , 12:39:53 AM » Yeah.  All you engineers on this forum are waaay better than those Honda jerks.  Heck, they can't even make a bike where all the rubber components lasts 35 years, maintenance free.  What incompetents!  How could they NOT have foreseen the imminent chipping off of fuel line rubber bits by home schooled mechanics?

What were they thinking, only one fuel supply filter.  It's negligence, I  tell ya, Negligence!  They must have it in for biker punishment.  Any lawyers on here want to start a class action suit, so we can recoup the cost of all the carb rebuilds, pain and suffering, etc.?

Gonna buy me some stock in a filter company, me thinks.   I foresee a huge upturn in future business.  Maybe THAT will get the economy back on track!  The future looks bright!


 

Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL

Those that learn from history are doomed to repeat it by those that don't learn from history.

Buber

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Re: For those of you who run inline fuel filters

« Reply #18 on: March 26, , 03:04:52 AM » A ha ha... very funny. As it happens it was not Honda fuel line. But no matter. With hard-core approach like that, of course you're right. But now, let's go back to planet earth, where not everybody is swapping everything in their old bikes for NOS parts, but just tries to ride the bike now and then...

So, when you ride your 30+ years motorcycle, nothing ever happens? is that right?

I honestly don't want to argue or fight. My previous post was just saying that fuel filter may have sense after all. And despite immeasurable wisdom of Honda engineers of their day, there's still room for improvement, and this forum is the best example of it. Ask Hondaman.

Use the filter if you want. I will, because it costs me nearly nothing, yet it may prevent "something".

peace..... Welcome to my mountains!
Mountain Chalets

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