Some interesting problems here..

[Danjal]

Basic info: 85' GS550ES, K&N pods, 4-1 exhaust, Dynojet stage 3 kit.

Long story short the bike has sat for 14 years, and ive put about 200 or so miles on it since then. Just minor and petty problems really. Well this one came up now and its got me scratching my head.

Id go out riding for the first few times and the bike ran great. Not a single problem. After that, I would start the bike up sometimes and it wouldnt get over 5-7k rpm's. This would usually happen after I ran it the second time. Id start it up again and it would run fine the third. Not a single problem. Time between startings was random, and it wasnt always consistent. It always ran fine on the centerstand.

So you're all thinking petcock filter by now right? Same here. SO...

I just got done cleaning the tank. Rattled some shot in there to clean it up. Came out extremely dirty.... 4 times of adding a quart of fuel in it and shaking away with the shot in it it came out decently clean, I gave it another go and it looked good finally. Replaced the lines with 1/4" ID hose, filter, cleaned up the petcock assembly and filter on it, flushed out the last remenants in the tank. Squeaky clean now. Cleaned up the K&N air filters while I was at it, changed the oil. Cleaned up the sump strainer, replaced the oil cooler since it was leaking.

Now since you're up to key on info... The bike wont get over 7k on the centerstand. Nothing was done during all of the random running and not running periods except swapping out a fuel filter.

Any thoughts here guys? So far im thinking im going to raise the needles up a clip or 2 and change the fuel lines to a larger size. Clean up the carbs too for S&G just in case they're dirty. I highly doubt they are, the filters were both working well and kept the rust in the tank. Even the inline filter wasnt really dirty at all. I just thought it didnt flow enough and swapped it out. This time I swapped it out for a larger one yet incase the flow still wasnt enough.

I'll pull the plugs tomorrow too and see whats going on in the cyls and take a pic. With the dynojet kit its always ran rich at an idle.

 

[Macguyver]

First thing I would do is check to see what the maximum flow rate of the fuel filter is. A very high percentage of the time that people install in-line fuel filters, they have similar problems, caused by the addition of the filter. I too installed an in-line, and my bike had a bevy of problems because of it. Wouldn't run high RPMs, didn't run smooth, impossible to tune, etc...

The filter on the petcock should be sufficient to your needs, if not, the tank should be cleaned and sealed to prevent contaminated fuel. Most small filters available are pretty crap when it comes to high demand flow rates such as those on a large displacement motorcycle.

The only real difference between the small inline and the larger one will just be that, it's bigger, but still likely has the same crappy filter element material in it as the smaller one. Sure it may flow more fuel than the small one, but does it flow enough? Not likely IMHO.

Most of the paper element filters are designed for more of a lawnmower to golf-cart flow rate.

Unless the filter is designed for motorcycle use, I personally would get rid of it. Seal the tank if need be, get rid of the in-line filter, then you know fuel supply is definitely not the cause. Make sure the carbs are clean, no air leaks in the system, then proceed from there.

Best of luck, and put up some pics, maybe a pic inside the fuel tank? One of the filter perhaps?
Just my 2 cents,

 

[BassCliff]

Hi,

I suspect a fuel starvation issue for the following reasons:

1/4" hose is too small for the fuel line. Try regular 5/16" fuel line.

ANY debris, no matter how small, that makes it from the tank into the carbs will block the small passages in there. Inline fuel filters can cause fuel restriction too. Make sure your fuel hose makes a direct line to the fuel inlet on the carbs, no bends or loops.

You probably need to clean your tank better and clean your carbs again.


Thank you for your indulgence,

BassCliff

 

[rapidray]

Don't make any adjustments to the carbs till you have removed them & CLEANED them! The bike ran good before & I have seen main jets not tightened & fall off & cause the issue you are having. After cleaning & reinstalling the carbs, sync them. Then, if it still happening, use a Mityvac to put a vacuum on the petcock to check the fuel flow rate with the petcock on "on" & "reserve". I think you will find the issues in the carbs or petcock. If not, start checking the output of the charging system & do a load test on the battery. I've seen some bikes that would run but not to full potential because the stator was making power still but not enough. Also, those pod filters you have are NOT available anymore so BE CAREFUL with them! Ray.

 

[Danjal]

Will do guys. I'll take the half ass method tomorrow and up the line size. If that dosent work, its on to the carbs. The fuel filter is for a motorcycle, but i'll omit it when I toss in the new line just to rule it out to troubleshoot. The sator checked out fine.. a month ago if that? The battery is brand new this season also. I upgraded to an AGM type. Still not im discounting either one as a problem yet, but it worked before and gave off and on results. Plus add in the tank and im going with fuel on this one until its all checked out.

Ive heard before those pods are rare, and I tried looking up a set on K&N site and the rest of the internet. I couldnt find them anywhere. No matter how I looked or using the parts number specifically. I did find a vintage K&N ad where they were sold off as a kit with the filters and a jet kit. I like to have replacement parts on hand. But it seems this bike wont be getting a backup set anytime soon.

The tank was shook up 5 times. First time I added no fuel and just used what wouldnt come out of the fuel cock on prime. I added a quart everytime after. Shook for 15 mins each time, drained without the fuelcock in, added a fresh quart of gas, shake drain repeat until clean. My arms are friggin tired right now.

Heres the first 2 shake ups. After these it got progressively better. The 3rd came out brownish orange and the 4th was much cleaner. After the 4th I rinsed it out to remove any sediment leftover.

1st one.

Second one

Thanks for the input guys.

 

[BassCliff]

Hi,

Check my website for some tank cleaning procedures. I used Evapo-Rust and it worked beautifully.


Thank you for your indulgence,

BassCliff

 

[Macguyver]

Hi,

Check my website for some tank cleaning procedures. I used Evapo-Rust and it worked beautifully.


Thank you for your indulgence,

BassCliff

+1 on the evapo-rust, by the look of the drainage from the tank, you definitely need it before you can sort out anything else with the bike. The good news is it's relatively cheap, and I am sure you will find other bits and pieces along the way which could use a good soaking in it as well.

Also, +1 on everything Mr. BassCliff has on his site. He's member of the Year for good reasons.

 

[Big T]

Looking at your pics, I'd start with a complete tank cleaning and lining and work your way downstream from there.

I think you'll just be chasing your tail with endless carb cleaning based on all the rust in your tank

 

[Danjal]

Will do.

Got the larger sized fuel line in, fitted it with no filter on it, ran the bike... 7k tops again. Carbs are pulled for a dip and a cleaning. Pulled cyl 1 plug. Black around the outside edges and tan in the middle. Its idled rich from the dynojet kit, but always ran fine before at higher speeds. Full tank overhaul on its way and full carb cleaning. Following that up by a resynch and retune if it needs it. I'll leave the carbs as is when I reassemble and see how far off they are from there.


EDIT:
Rust and bluing remover? Oh I see this being bought in bulk now if it works. Heres my other hobby. Tons of links in the photobucket if you're interested.

 

[Clone]

Will do.

Got the larger sized fuel line in, fitted it with no filter on it, ran the bike... 7k tops again. Carbs are pulled for a dip and a cleaning. Pulled cyl 1 plug. Black around the outside edges and tan in the middle. Its idled rich from the dynojet kit, but always ran fine before at higher speeds. Full tank overhaul on its way and full carb cleaning. Following that up by a resynch and retune if it needs it. I'll leave the carbs as is when I reassemble and see how far off they are from there.


EDIT:
Rust and bluing remover? Oh I see this being bought in bulk now if it works. Heres my other hobby. Tons of links in the photobucket if you're interested.

:-k
So you're an arms dealer?
:-k

 

[Danjal]

No, im a shooter, kit builder, upgrade, repair, customize, etc etc. I dont deal arms for money. Thats all my private collection. Anyway... heres the spark plugs. They all look like the individual plug in color, but they were showing up correctly in color as a group picture.

 

[Danjal]

Pulled the carbs and took the bowls off. Sediment is in the bowls. Very very fine particles of rust from the tank. They bipassed all the filters and never clogged a single one on their way through. Redipping, evapo-rusting, new gaskets, new fuel, new filter.. you get the idea. Clean it all and replace it in the fuel system.

 

[Beaver]

Just a quick question for you Danjal, you have a Dynojet kit on a 550, I though you couldn't get them for anything smaller than a 1000. How does that work?

Cheers

Angus

 

[Danjal]

They sell kits for about everything. Im here in the states. DJ makes a stage 1 and a stage 3 for the 83-85 550's like I have. And I couldnt tell you how it works since one was always installed on this bike from the get go. It was one of those $400 U-fix-it bikes. The PO changed some jets around from the original kit, so I bought a new set of carbs and a new stage 3 kit.. installed it myself. That cleared up most of the problems I had. It ran rich at an idle before, and still does now. But before this tank cleaning problem it would run amazing all the way up to redline. I never checked redline out of 2nd or 3rd just do to my lack of riding experience. Otherwise it ran smooth under little throttle the whole way up 10 10k. No complaints here. I think this bikes going to be around with me for years unless I get bored of it and move up to one of those new fangled 600cc's with EFI and plastic all over. Shes not the fastest bike out there, but she still has more then enough to get me into trouble. If theres anything else you want to know ask away. It was pretty hassle free doing it. Tuning takes longer then install. Even carb removal for that matter.

 

[Danjal]

Just an update on this and some more problems.... yay.....

Finally cleaned the tank. After an initial evaporusting and some lead shot (as you can see the pics in there before.. it was still rusted internally because of tank sealant from one of the PO's. *bangs head* So.... tossed some laquer thinner in there with some heavy 3/4" nuts... shake shake shake. And out comes the goo.. For about a week straight I was pulling bits and pieces of dissolving tank sealant or something out of there. It was clear originally, then turned white and milky when the thinner was on it.

Anyway, evaporust job number 2 worked like a charm. Every hole, nook cranny, etc I can see with an inspection mirror is bright and shiny now. Tossed in some gas swished it around... drained. repeated, ran it through a piece of paper towel to check for rust residue and it came out completely clean. Reassembled the tank and now the bike fires up and runs... at 9k maximum.

Fuel lines are new 3/8", carbs were dipped in berrymans and air blown out, cleaned out the pods and reoiled with K&N airfilter oil, replaced the plugs and regapped, even checked and cleaned the petcock without taking it apart. It works fine with suction, dosent leak unless its on pri.

So what gives? I reset the carbs to exactly where I had them set last time they ran good. Granted I havent rebalanced them yet, but it should free rev up to redline. Opinions? I get this feeling I'll be moving needles here soon but im hesitant to do so since it was running so well before it started this stuff. Electrical problems maybe?

 

[Danjal]

Just got back from riding. Its definetly fuel starvation to the carbs. Im assuming my petcock just went south.

Bike will not go over 9k free rev. Wont go over 7k with me on it in ANY gear. I down shifted to see if I could get over "wall" to the fast system in the carbs and it ran fine for a few seconds then died and had no fuel at all to restart until it sat for a min on "PRI".

Clean tank, clean carbs, known good tune, new plugs, new lines with no filters installed.

Pretty much leaves the petcock suspect dosent it?

 

[Danjal]

New petcock in... STILL persists at staying at 9k maximum on free rev. *Bangs head* I installed a second good used petcock from a friend.. same problem. So thats 3 petcocks all the same problem. The only other thing I could do would be drill one of the suckers out and leave it as an elbow off the tank, but I think thats unnecessary at this point. Recleaning the carbs...again.

Any Ideas?