Hello,
I have been having an intermittent problem with my GS500 and I am hoping someone might have an idea as to what might be the cause. It has only happened about 4 or 5 times and it appears to only happen when I am in top gear.
The first two times it happened I was in top gear with the throttle fully open when the bike started to hesitate. Soon enough I was not getting any power and I had to gear down until the bike stalled out in 1st gear. I then waited on the side of the road for a few minutes started it back up and the bike was fine for weeks before it would happen again.
The last few times it happened however I was in top gear but I did not have the throttle fully open, I was riding at around 6000rpm. 2 of 3 times it stalled out in 1st gear, as before, and all I had to do was open the choke, start it and it would run fine. 1 time however I got down into 1st and instead of stalling it seems to rectify itself and I could keep going. Unfortunately it would act up again further down the highway and stall out as per normal.
Now, when it hesitates it kinda feels like it is running out of gas (only I have lots of gas in the tank). So I thought maybe something with the fuel system. Some people have since indicated that if it was the fuel system (ie. not getting enough fuel at full throttle) it would appear in other gears as well...not only top gear. They suggested that it could be my ignition coil since it will only break down under heavy load (which explains why it happens in top gear).
Before I go tearing my bike apart in an attempt to fix this I was hoping someone might know what is the cause. To be honest I will probably go over both the fuel system and the igntion coils this winter when the bike is off the road but if someone can enlighten me in the mean time it might mean I can get this particular problem resolved sooner rather then later.
Thank you
Derec
Sounds to me like the a common problem with GS's. Do a search for fuel starvation and you will find there are 2 main culprits, the vacuum petcock, and the vacuum locking in the tank due to a clogged vent in the filler cap.
I would check the petcock on the frame,change the fuel filter and possibly remove and clean the carbs.I would purchase a good manual,if you haven't all ready.Even if you don't do your own maintainance,it'll help you deal with mechanics.Good luck.
yes. check the racer mods section youll see that for racing the stock fuel delivery is inadequate. at long periods of full throttle, the bike just cant get fuel fast enough. the solution i believe is the pingle petcock mod. other than fixing this problem, it also makes the bike easier to work on without the mess of hoses under the tank.
it could also be the carbs, or fuel filter, so dont rule those out. often a problem is caused by a combination of things. i.e. 3 systems working at 85% effectivness together = more than 15% chance of failure. id bet that fixing the petcock will solve the problem, but fuel filters are cheap, easy to replace.
as for the carbs, i would do that last and only if the other solutions dont work.
Hm, this issue. Had it a few times and also had to stop by the side for a few minutes before it ran completely fine again.
I read that priming (PRI) helps. I'm sure Scratch or Pandy would know. When I'm going on a group ride, I leave it on reserve or prime. Definitely don't want fuel starvation while going through the twisties.
That for the info everyone.
I am actually kind of happy to hear that my original assessment was in the right direction.
:)
I ride on "pri" all the time if I don't I have the same issue. Last time I passed a few cars and as soon as i got passed them I had the same exact problem. I also have an 89'. I notice if I leave the bike at that setting wial not riding I get a strong gas smell.
Leaving the petcock on PRI bypasses the vacuum portion of the frame-mounted petcock, so when you are not riding it will leak fuel if you float bowl needle and seat is worn. Or in otherwords just make sure that you turn the petcock back to ON when you are done riding to prevent this.
I just went through this problem. Put it on PRI and try to recreate the problem. If it doesn't happen you can narrow it down to the fuel filter, petcock, and fuel lines.
This is what I did and I had no problems. The fuel valve on the tank was open maybe 95% of the way, and one of the fuel lines was slightly kinked. I fixed both and now I can ride on "ON" all the time without hesitation or problems.
Yay for the "search" feature. :thumb:
Thought I would throw in an update on this.
So...after stopping on the side of the highway many many times now. Trying numerous things to try and narrow down where the problem lies and even talking to my shop I think the problem (for me anyway) lies with my tank. Here is how I have come to this conclusion.
1. The problem manifests (or has recently anyway) even in Prime (I don't believe this should happen if it was merely the Pet chicken)
2. The problem only manifests when I am in the low half of my gas tank (after about 175-200 km). Never occurs on a Full Tank.
3. When I had the problem yesterday (twice...once on Prime and once on On) I decided to ride with my Gas Cap open and I never had a problem the rest of my ride.
I will know for sure soon. Some dumbass back into my bike a week ago and it goes into the shop on Monday to get parts replaced (at the dumbasses expense of course) so I figure I will have them check out the tank while it is in there.
Derec
I spray WD-40 in the cap vent and it seems to keep it from sticking shut.I only do it once a month or when I change my oil.
Time for another update!
Shop made sure my Tank was all good (venting, shut-off valve) and filter. They also shortened my gas lines and cleaned my Pet chicken. From what I understand the Pet chicken looked good and did not have much gunk but my lines (near the filter) were pretty bad...deteriorating (sp?) or something like that.
Either way...the end result is a bike that runs well and has no more fuel starvation problems!!!
YAY!!!
:D
I had my bike up to 150km/h (normally 140km/h was pushing it and problem manifested real quick) for the first time this season and was able to keep it their for 5 min+ without a single problem.
Derec
Great News Dude ,Happy Riding !