OK. I am new to the website and I have looked EVERYWHERE! I really mean it when I say everywhere.

Here's what's happening to my baby. Bought it 3 weeks ago from some guy (seemed like a honest guy). Bike was working fine, idle was OK, i wouldn't say perfect because i needed the choke on or else it would die.

Anyways, since yesterday morning on my way to work the bike was running fine, doing my normal 65-70 mph. then from the nothing, it started to lose power as if the throttle wasn't working, but i would wind it more and it would keep going, i let off the throttle and the bike dies, as if I had turned it off. I pulled to the side of the road and it wouldn't start back up for nothing (and i tried for like 10 times). called my wife, she was on her way to pick me up (approx. 5-8 min) the bike decides to start back up. I don't know what's wrong. I tried it at work, drove it around the block and it seemed fine. then its time to go home and AGAIN, I get stuck on the highway for about 15 minutes this time b4 it decided to start back up.

Any information/suggestion will be considered. Please help a twin brother out with his new toy.

thank you

sounds like the fuel isn't getting into the carburetors fast enough, thus you have to let it rest/collect for a few mins.

could be a blockage in the tank vent, petcock, fuel lines, carburetor, etc

I had the same prob with mine last week and it was a result of poor fuel flow from the tank petcock.  Found rust in the tank.  After my intervention (which was the wrong way...so I won't share details) of cleaning my tank and lines out....The flow is very good now.  A good way to see if your carbs are starved when it dies is to install an in line filter from your frame petcock to the gas line going to the bottom of the carbs.  Simply cut your line and shorten it by an inch or so.  Put in the filter and clamp it.  It helped me because as soon as I stalled I would look and the filter was empty.  Get a see through filter so you can monitor this.

Had to chime in because it sounds exactly like what mine DID do.......and doesn't anymore.

Also, check to see if you get flow turning to "prime"......Do not leave it on prime when it's parked. 

Welcome to the forum....I am willing to bet there is not a problem you are having that has not been solved by someone or many on this forum.  Its the digital bible of the GStwin bikes.

Best of luck to you...Be safe.

Scott

you should always use the choke to at least start the bike. if you can start it without the choke, you have one special GS

make sure you have gas. if you do, check to see what your petcock is set to.

the gs is known to have fuel starvation issues at speed. usually you can just switch the prime and itll solve the issue.

if you have a full tank, switch to prime, and still have issues: check the routing of some vent hoses. there are some vent lines that stick out into the air and get muddled by the wind hitting them

Thank you all for replying.

I currently have a filter. when the bike died yesterday on the way home I kept checking the fuel lines... I noticed the filter had sort of air in it. i would say it looked like a bubble. waited a little more and looked at it again and the filter looked as if it was almost empty. (just filter, the lines had gas in it.) I checked inside the tank and it looked a little rusty on one spot. how do i get that out?

I know I have to re-do my fuel lines, but could it be the filter's fault? and where can i buy a new one. it's pretty small like the ones for lawn mower.

I wouldn't say the lines are connected wrong or else i would've had problems from day one. and again this only started yesterday.

thanks guys.

the air bubble wouldnt go away with switching the bike to prime? if the filter is old/clogged it could affect the fuel flow.

and you should double check the routing of your hoses just in case anyways.. there are plenty of people who've had issues because of a pinched hose or incorrectly routed system. the tank will let gas out as long as the tank petcock is open and there's fuel. you could have the lines installed incorrectly but still be ok.

I had rust pieces that were effecting the primary fuel line......not the reserve as much.  When I was draining tank the flow was 1/2 out of that line.  The line was new so it was inside the tank petcock.  My fuel filter came from Autozone......couple bucks paper element type.  When my bike would die going up the mountain.....I would pull over and look at the filter.....empty.  Would wait for a minute or so.....it would fill except for the bubble you described.  My tank petcock was fishy because the screw turned horizontal should be off and on for vertical.  I have to turn mine and find the "sweet spot" which leads me to believe there were some fragments blocking it if it was turned one way or another.  My filter was found to be clogged when I last messed with it.  I just wiped it off and blew through it opposite the way fuel flows.  It was a week old or I would have bought a new one.  It cleared just fine.  *This may not be the best way.....but is a way.  Don't blame me if you get lip cancer for kissing a fuel filter!

I tried what pand was suggesting by turning to prime......it didn't correct mine because it was in the tank petcock where the problem lived.  Good luck to you.

Fortunately your problem is easy to diagnose: you have fuel starvation.

Let's start with the obvious:

Did you try switching to prime yet?  If the problem goes away you don't have enough gas.  Fill it up.

Switching to prime didn't help?  Fill your tank up all the way and try again.  If the problem goes away but recurs partway through the tank, either the inline filter is clogged, the frame petcock isn't great, or your tank petcock is occluded.  Is the inline filter a clear brass type or paper?  You have to use a small engine type, not a paper filter.

Same symptoms with a FULL tank?  You could have rust particles in your carbs.  The frame petcock might not be working right.  Switch to prime with a full tank.  Does the problem go away?  Switch back to normal and the problem comes back?  It's your frame petcock.  Replace it with an 04+ model frame petcock from ebay.  Problem occurs regardless of petcock position with a full tank?  Rust somewhere or clogged inline filter.  Replace the inline filter with a small engine brass style.  Problem still occurs?  Clean your carbs and remove the tank petcock and clean it.  If you find rust anywhere, clean and seal your tank.

QED

Okay so an update to see if it helps you helping me  .

I just got back from a ride running on ON. Started to chock and almost died until i switched to PRIME. the bike ran great, low speed or high speed. But shouldn't the bike run on ON normally?

What i noticed was. if you look at this diagram -> http://gstwin.com/fuel_hose_routing.htm

when petcock is in ON, the fuel line coming out of #4(frame petcock) into #2(tank petcock) seems to have more air than gas going through it and you can see the filter getting empty and letting bubbles into the carbs. when you switch to either RES or PRIME the hose fills back up with gas and the bike idles back to normal(also the filter fills back up with gas).

Only when its in ON position it does that.

so i guess the problems is somewhere easy but i cant figure this out since its my first time. Like i said, bike ran great while in PRIME, did about 80 mph on the highway with no problems, switched it to ON and it started chocking because there's not enough gas going through it.

thanks

your petcock diaphram is most likely bad.  rebuild petcock should fix the problem or you could do the petcock mod that removed vacuum operation of the petcock all together.  I personally would just rebuild the petcock.

With a full tank I say this is blockage in primary line or if new in the primary side of the tank petcock.......(like mine)  Cause........rust in tank.  Diagnostic......blow air backwards through primary line with frame petcock in the "on" position.  If corrected it dislodged the rust on the primary fuel line petcock port.  Bet ya $10 = rust in your tank.