:p with all the fairings off the bike and no windscreen my top end is struggling. around 130km/h. does this make sense?

Your not tucking enough. I managed a dollar 70

.... Depends on how cold it is and if there's hail... Besides you should wear clothes while riding...... Oh wait.... My bad... 

Whether faired or unfaired I have managed 160 ... Ummm .. 'On a track somewhere!' ... On my bike, come to think of it... I don't really bother to try tuck in until after that speed! ... On flat ground at least it should go better than 130!! ... Some other issue going on there I think?!

Quote from: slipperymongoose on June 28, 2013, 03:52:20 AM
Your not tucking enough. I managed a dollar 70

Did you tuck it or tape it?

No tuck, no fairings, and with a big Plexi 2 windshield on my 97 GSE back in June 02 I had my bike and 240# me up to 110 mph indicated.  Probably around 100 mph honest speed.  Bike completely stock, yours should do better than 130/1.6= 81 mph naked or faired.   

Quote from: Twisted on June 28, 2013, 04:50:13 AM

Quote from: slipperymongoose on June 28, 2013, 03:52:20 AM
Your not tucking enough. I managed a dollar 70

Did you tuck it or tape it?

Tuck, silence of the lambs style

I saw my clock tell me it was 1.85 o'clock? At one stage. Must get that clock fixed


Sent from my iPad using a big stick

OK. this leads me to believe that its my exhaust. its a yoshi slip on. during a crash it punctured a Hole in the top end. so i cut in half. is it possible that this would affect the flow. my engine is practically brand new. great compression in both cylinders. however I have a small issue that my bike only runs on prime.

If it's stumbling at high speed AND only running on prime, my guess is a kinked fuel line, or dirty petcock. Not getting enough fuel to the engine at higher speeds. Plus with a hacked exhaust you are probably running the wrong jets. Lean or rich...not sure which way it would be with a hacked Yoshi. Pull plugs, what color are they?

the tip of the plugs were black the last time I checked. I feel like its not the petcock because I replaced it last year..but that didn't fix the issue. could be a kink however but I feel like its my pipe.

If they are black you are running very rich. They should be a light brownish. If you are keeping the exhaust, then you need to swap the jets to lean it out. This would explain a lot of the bogging and sluggish nature...especially at the top end.

yeah I want to change my exhaust system anyways. I feel like it should fix the problem. ever since the crash the top end was garbage so hopefully a rejet will fix it. can the exhaust be the cause in why it only runs on prime?

No, that would be completely separate. Get your replacement exhaust mounted before you rejet, otherwise you will most likely be wasting your time.

As far as only running on Prime, make sure you have your fuel hoses connected properly, it's easy to swap them. Do you have a fuel filter? If so, chuck it.

Quote from: Soloratov on June 28, 2013, 10:58:38 AM
As far as only running on Prime, make sure you have your fuel hoses connected properly, it's easy to swap them. Do you have a fuel filter? If so, chuck it.

I'm curious do you always run premium fuel as you don't have a fuel filter?

Premium fuel is just as "dirty" as regular fuel. An inline filter is much more likely to get clogged from small particles ofdirt.

I personally had an inline filter for one season after I bought the bike, only because I had to do a decent cleaning job in the tank and wanted to make sure I caught any junk...after that, I got rid of it.

Quote from: Big Rich on June 29, 2013, 06:50:08 AM
Premium fuel is just as "dirty" as regular fuel. An inline filter is much more likely to get clogged from small particles ofdirt.

Apparently there is a fuel filter built into the tank is that correct?
So you just run regular unleaded all the time?

Correct.

I've never seen a GS500 tank up close (remember, I don't own one) but every bike has some type of fuel filter from the factory. Like Solaratov, I run additional filters - but only in certain conditions.

There is a small screen filter inside the tank, yes. But that is normal for...well...all bikes as far as I know. Fuel filters have nothing to do with what octane fuel you run. As far as I know all model years for the GS are rated fine with standard low octane fuel. No reason to run the high test stuff in my opinion, but thats all personal preference anyway. That is a long debated item here on the forum...so I'm not starting that argument again. Fuel filter is for "stuff" in the tank.

an update. my bike is actually running very lean. the fouling on my plugs were from my old bike. Im waiting for my replacement exhaust before I rejet it. Should I be worrying about riding the bike when it's too lean. What im assuming is that my bike is getting too much air versus fuel? Other than a kink in my fuel line/dirty petcock, what else could the issue derive from?Any way that it can be my carburetor?