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Main Area => General GS500 Discussion => Topic started by: ver4 on July 30, 2009, 04:53:21 PM

Title: More Problems
Post by: ver4 on July 30, 2009, 04:53:21 PM
Background:
Bike wasn't running right, so the carbs were taken off and cleaned and synced.  When it was started it was running on both cylinders (about two weeks ago). 

Rust was in the tank, so my Dad derusted the tank and lined it and installed the tank and petcock back onto the bike.  Now (present day), the bike is only firing on one cylinder.  Gas is getting to the carbs and to both the cylinders.  Spark plug wires show spark, but the left cylinder still doesn't fire.

I don't understand how both cylinders can be firing one week and then two weeks later with nothing done except installing the tank back onto the bike it now only fires in the right cylinder.

Any suggestions?

Thanks in advance.
Title: Re: More Problems
Post by: JB848 on July 30, 2009, 05:14:46 PM
OK I know this is dangerous but let us assume the coil is good.

You say that both spark plugs have a spark and I would hope you mean a bright one and both plugs have the same gap.

1. try frogging (switching) the spark plugs and wires. Does the cylinder firing change? No go to step 2. Yes, get new spark plugs and wires and go back to 1
2. Check the fuel lines. Take off the fuel lines and blow through them. Are they clear? No, replace fuel lines and start at 2. Yes, take carbs back apart you have foriegn material in the carbs.
3. After you have done 1 & 2 come back and post results.
Title: Re: More Problems
Post by: ver4 on July 30, 2009, 05:18:43 PM
I will do this Sunday as I'm heading to Pittsburgh tomorrow. Thank you.

Title: Re: More Problems
Post by: BaltimoreGS on July 30, 2009, 06:33:22 PM
My bet would be on a clogged carb.  Did you add an inline fuel filter to your bike?  That seems to help.  Pete's and Cycle World both sell them for a couple bucks.  Pop your carbs off and clean the float bowls and jets again.  That big dent in the top of the black tank on Kay's bike is from when the carb got clogged twice in the same day and I lost my temper.   >:(  Not my proudest moment.  That tank has a recurring rust problem.  The tank we are  re-painting for her bike was coated by Cumins Radiator down at 3200 Washington Blvd to prevent me from having future carb related flip outs  :icon_lol:  Good luck!

-Jessie
Title: Re: More Problems
Post by: ver4 on July 30, 2009, 06:50:17 PM
Maybe I'll just buy a Busa even though I have only went riding a couple times, insurance would be a killer and I can't afford it.  :D  Then I can drop it a couple times, get into an accident and say it was someone elses fault.  :flipoff:

I hope this thread doesn't disappear too far over the past couple days.
Title: Re: More Problems
Post by: BaltimoreGS on July 30, 2009, 07:23:41 PM
Nice plan! Make sure to wear flip flops and a wife beater when you wreck it   :laugh:  Have a good trip and let us know what you find when you get a chance to work on it.

-Jessie
Title: Re: More Problems
Post by: The Buddha on July 30, 2009, 07:41:23 PM
Left cyl not running and tank and carbs removed = vacuum line disconnected and hooked back up wrong.
Cool.
Buddha.
Title: Re: More Problems
Post by: ver4 on July 30, 2009, 07:52:43 PM
We noticed that the bike wouldn't idle except on choke, so my Dad disconnected the vacuum line and "plugged" it wiith his finger and it would idle fine.  I'm assuming the petcock may be bad.  Does this information that I forgot to include help any?

Like I said, once I get back (Sunday), my Dad and I will look everything over again.
Title: Re: More Problems
Post by: 08GSSteve on July 30, 2009, 10:22:01 PM
Good possibility you have crap in a carb.  I had a small bit of rubber (from poor fitted fuel line from factory) go into the carbs which caused the left plug to get wet and not fire (flooded).  I knew it was the carbs but took the dealer 2 times pulling the carbs off cleaning them to get it right.  (I paid for warranty may as well use it and make stealer fix it).

It's a pain removing carbs and cleaning but by what you said with cleaning then 2 weeks later no spark I am leaning towards a blocked carb again.

OR

could be simply a dodgy plug?

JB848 hit the nail on the head.  Do his test method to eliminate this.

Good luck
Title: Re: More Problems
Post by: ver4 on August 01, 2009, 10:04:28 PM
Apparently the carbs are dirty.  Dad took them off while I was in Pittsburgh and he's cleaning them again.
Title: Re: More Problems
Post by: BaltimoreGS on August 02, 2009, 06:36:05 AM
Do yourself a favor and install one of those little fuel filters while you have it apart, they seem to help.

-Jessie
Title: Re: More Problems
Post by: The Buddha on August 02, 2009, 07:51:25 AM
Quote from: ver4 on July 30, 2009, 07:52:43 PM
We noticed that the bike wouldn't idle except on choke, so my Dad disconnected the vacuum line and "plugged" it wiith his finger and it would idle fine.  I'm assuming the petcock may be bad.  Does this information that I forgot to include help any?

Like I said, once I get back (Sunday), my Dad and I will look everything over again.

This = something in the vacuum line is bad. Maybe petcock ... maybe line itself.
Carbs getting dirty so fast after cleaning = rusty or very dirty gas tank.
Cool.
Buddha.
Title: Re: More Problems
Post by: ver4 on August 02, 2009, 08:55:07 AM
Quote from: The Buddha on August 02, 2009, 07:51:25 AM
Quote from: ver4 on July 30, 2009, 07:52:43 PM
We noticed that the bike wouldn't idle except on choke, so my Dad disconnected the vacuum line and "plugged" it wiith his finger and it would idle fine.  I'm assuming the petcock may be bad.  Does this information that I forgot to include help any?

Like I said, once I get back (Sunday), my Dad and I will look everything over again.

This = something in the vacuum line is bad. Maybe petcock ... maybe line itself.
Carbs getting dirty so fast after cleaning = rusty or very dirty gas tank.
Cool.
Buddha.

The tank just had all the rust removed and lined.  He's coming over today as long as the rain holds up, so I guess we'll go from there.  It may be a vacuum problem too....that's kind of what I was thinking since it idled fine when he plugged it.

Title: Re: More Problems
Post by: ver4 on August 02, 2009, 08:55:57 AM
Quote from: BaltimoreGS on August 02, 2009, 06:36:05 AM
Do yourself a favor and install one of those little fuel filters while you have it apart, they seem to help.

-Jessie

Where do I get one of these?
Title: Re: More Problems
Post by: joshr08 on August 02, 2009, 08:56:36 AM
auto parts store all you need it to give them your hose ID size.
Title: Re: More Problems
Post by: ver4 on August 02, 2009, 09:00:46 AM
Alright...thank you.
Title: Re: More Problems
Post by: BaltimoreGS on August 02, 2009, 10:14:08 AM
Be careful getting one from an auto parts store, they may not flow enough fuel on your motorcycle since the carbs are gravity fed (no fuel pump) leading to a fuel starvation problem.  Make sure if you do it is meant for a motorcycle, not a car.  Or just stop in Pete's or Cycle World, they both have the little clear plastic ones hanging on a wall display behind the parts counter. 

(http://treats-of-the-loin.com/images/moped-fuel-filter-clear-blue.jpg)

Make sure you pay attention to the flow direction arrow.  Good luck!

-Jessie
Title: Re: More Problems
Post by: ver4 on August 02, 2009, 02:07:13 PM
So there was a broken O-ring on one of the carbs that needed to be replaced.  The vacuum ports are closed off now.  It seems to drive fine.

I believe all that's left is the rear tire changed, replacing old rotor with newer rotor plus brake pads, and getting the darn thing inspected and registered...
Title: Re: More Problems
Post by: JB848 on August 03, 2009, 12:52:27 PM
LMAO, well we all said CARBS, CARBS, CARBS I guess we were all right. Did the O-ring split after reassembly or did you guys just miss it you think? I used to rebuild carbs all the time and my general rule was if I take it apart have a gasket kit ready, and if you take it apart replace everything needed or not! Why waste your time?

I'm glad you found it though.
Title: Re: More Problems
Post by: ver4 on August 03, 2009, 01:53:46 PM
Quote from: JB848 on August 03, 2009, 12:52:27 PM
LMAO, well we all said CARBS, CARBS, CARBS I guess we were all right. Did the O-ring split after reassembly or did you guys just miss it you think? I used to rebuild carbs all the time and my general rule was if I take it apart have a gasket kit ready, and if you take it apart replace everything needed or not! Why waste your time?

I'm glad you found it though.

I think we missed it, but who knows.   :cookoo:

Update:  Tire and rotor installed.  Not too much longer for it being road ready.  :thumb:
Title: Re: More Problems
Post by: BaltimoreGS on August 03, 2009, 07:37:59 PM
Sweet!  We have to get another Maryland ride organized soon!!

-Jessie
Title: Re: More Problems
Post by: ver4 on August 03, 2009, 08:00:31 PM
Quote from: BaltimoreGS on August 03, 2009, 07:37:59 PM
Sweet!  We have to get another Maryland ride organized soon!!

-Jessie

Definitely.  I am going tomorrow or Wednesday to get the bike inspected and then all I have to do is collect/make enough money to get it registered.

If this thing doesn't pass with all the work that has been done to it, I might go crazy.  :2guns: :D
Title: Re: More Problems
Post by: ver4 on August 05, 2009, 02:15:12 PM
Well......it didn't pass.  :cry:

They failed it b/c of the high beam indicator light.  I'm glad it's an easy fix and I'm going up to the inspection station tomorrow to install the light and then it will pass.  :woohoo:
Title: Re: More Problems
Post by: BaltimoreGS on August 05, 2009, 03:46:49 PM
Well at least it was something simple thise time   :D

-Jessie
Title: Re: More Problems
Post by: ver4 on August 05, 2009, 05:42:03 PM
After inspection I'm going to go and get it registered too.  My sister paid me back the money I used for some of the bills.
Title: Re: More Problems
Post by: BaltimoreGS on August 05, 2009, 06:35:16 PM
Cool, hit me up when it's all legal and we'll get PachmanP down for another ride.  Hopefully his bike is back together....

-Jessie
Title: Re: More Problems
Post by: ver4 on August 05, 2009, 07:01:45 PM
Quote from: BaltimoreGS on August 05, 2009, 06:35:16 PM
Cool, hit me up when it's all legal and we'll get PachmanP down for another ride.  Hopefully his bike is back together....

-Jessie
Alright