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Main Area => General GS500 Discussion => Topic started by: xaeniac on July 28, 2004, 08:16:44 AM

Title: riding 80-85 on the speedo for 1-2 hours
Post by: xaeniac on July 28, 2004, 08:16:44 AM
Since the GS500 has a 10% speedo increase can you run the bike at 80-85 on the speedo (really ~75 mph)for about 1.25 hrs without hurting the engine in superhot  humid Louisiana weather?
Title: riding 80-85 on the speedo for 1-2 hours
Post by: tdan553527 on July 28, 2004, 08:30:36 AM
I do it every day to and from work, I hope it doesn't hurt. I figure if they can race em around tracks at high speed for a couple of hours, it can't hurt my bike.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: straightforward on July 28, 2004, 08:40:03 AM
As this is lower speed than what is allowed here, I would not see a problem. Means cruising at 7.000 rpm, so what?

Just make sure your motor oil level is ok. Motor oil also has some cooling function.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Dragonfly on July 28, 2004, 08:56:00 AM
I wouldnt worry about it to much. What type of oil are you using??
I would switch to a thicker full synthetic. For  track days, and hard rides on hot days I Switch to a 20/50. It lubricats better at higher temps than say a 10/30.

I have ridden my bike on a few 350 mile sportbike rides, were we only stoped  a few times.
after Consistant floging to try to keep up. I have lost almost no oil, and it still actually has a nice color to it.
I use Castrol actevio 20/50 for the summer, 10/30 spring and fall,
and a 5/30 for the winter. it seems to keep the bike well lubricated after some brutal rides!

Maybe re-jet the bike as well. If you richen it up things will run a bit cooler.

Other than that I dunno...

Micah
Title: riding 80-85 on the speedo for 1-2 hours
Post by: xaeniac on July 28, 2004, 09:35:30 AM
I use castrol gtx 10w/40;  maybe next time I will switch to 20/50 weight.  Thanks for the tip.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: mp183 on July 28, 2004, 04:33:25 PM
I use Castrol GTX also and have run it for almost hours at an indicated 80-90 mph.  Many times I'll go at high speeds for 225 to 250 miles without stopping.  Your butt will give out before the engine will.  The harder you run it the better it will run.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: davipu on July 28, 2004, 06:33:12 PM
I ran Coastal 10-40 dino juice for 7000 miles burned 2 qts.  I am still running the same Chen Shin HiMax rear tire in a 130/90-17  with the taller tire I am running about 6000 in 6th gear at 80.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Cal Price on July 28, 2004, 06:38:08 PM
I concur with all of that, should not be a problem. Most manufacturers handbooks do caution against long periods without variance of the revs. As I see it such a thing could only happen if you had a road long enough, straight enough and level enough and I do not suppose there are too many of those about.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: mp183 on July 28, 2004, 06:53:54 PM
You are right about varying the engine speed.  I do that as a matter of principal.  Cuts down on the boredom.  It's also the key to successful speeding on the Thruway.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Rweimer on August 07, 2004, 09:32:18 AM
xaeniac:  i have a question:  are you saying that the speedometer is reading at ten miles per hour more than your actual speed?

is this a common problem that i just don't know about?

when it says i am going 45, am i really going 35?
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Kerry on August 07, 2004, 09:49:05 AM
It's usually more like 10%, rather than 10 mph.  (At least, that's what I've found on my bikes.)

So, at an indicated 45 you're going more like 40.5 and at an indicated 80 you're going more like 72.

No wonder all the cars on the freeway pass you like you're sitting still!  :lol:  (I say that from experience.  The first time I rode on the freeway I was flabbergasted that everyone seemed to be going 80mph!)
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Rweimer on August 07, 2004, 05:36:32 PM
Wow, that is good stuff to know.  I was commenting to a co worker that everyone seems to be on my tail, and I am doing 5 over the limit.  I guess I need to get my butt in gear.

You'd think they would find a way to correct this.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Rema1000 on August 07, 2004, 06:37:33 PM
I must be the unlucky guy, because at 74mph indicated, I'm doing actual 71mph... only about 4% off for me.
Title: Re: riding 80-85 on the speedo for 1-2 hours
Post by: Flash on August 07, 2004, 06:43:59 PM
Quote from: xaeniacSince the GS500 has a 10% speedo increase can you run the bike at 80-85 on the speedo (really ~75 mph)for about 1.25 hrs without hurting the engine in superhot  humid Louisiana weather?
I don't know about anybody else, but I've lost total power on at least 3 occasions from sustained high speeds b/c the fuel petcock (the one attached to the gas tank) could not flow fuel fast enough to keep up with me. I eventually emptied the gasoline in the carbs. That totally sucks. You've been warned.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: yamahonkawazuki on August 07, 2004, 07:00:04 PM
yup , one of the "few" gripes of the 'ol gisser
Title: riding 80-85 on the speedo for 1-2 hours
Post by: mp183 on August 07, 2004, 07:03:49 PM
I have a 2002 and never had that happen.  I have a feeling they finally solved that.  In fact my year seems to have no know issues.  It took a while to warm up before I re-jetted but I just ran it with the choke if I was in a hurry.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Dorianfes on August 07, 2004, 07:07:43 PM
that used to happen to me too.  after riding at high speeds for awhile it would start feeling like i was running out of gas, even when i switched to reserve, and eventually die on me.  i believe others have posted about this problem before.  stock petcock is pretty much a P.O.S.  someone, i think it was Kerry, posted about using PRI for long rides.  it works for me.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Flash on August 07, 2004, 07:37:19 PM
Quote from: Dorianfesthat used to happen to me too.  after riding at high speeds for awhile it would start feeling like i was running out of gas, even when i switched to reserve, and eventually die on me.  i believe others have posted about this problem before.  stock petcock is pretty much a P.O.S.  someone, i think it was Kerry, posted about using PRI for long rides.  it works for me.
Well, that is not an option for me b/c I removed the other P.O.S. petcock (On/Prime/Reserve) and all the vacuum tubes and put a straight fuel line to my carbs. That is how I know the fuel tank petcock is to blame.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Kerry on August 08, 2004, 01:15:58 AM
Quote from: FlashI removed the other P.O.S. petcock (On/Prime/Reserve) and all the vacuum tubes and put a straight fuel line to my carbs. That is how I know the fuel tank petcock is to blame.
Somebody said something the other day that gave me a new perspective on the whole fuel starvation problem.  The gist of it was something like "When the throttle is wide open there is less of a vacuum to operate the ON/RES diaphragm in the frame-mounted petcock".

If this is true, then the following may NOT be true:Can anybody confirm the assertion that
Title: riding 80-85 on the speedo for 1-2 hours
Post by: charleym3 on August 08, 2004, 03:51:56 AM
Hmmm.  I've only had one vehicle that had this problem.  It was a 69 Superbird.  With the stock fuel sustem it was starving for fuel at 150MPH.  I had to add a second pump and go to a 1/2 inch supply line.  Hope I don't have to do that to the GS.  There isn't as much room to work with. :dunno:
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Flash on August 08, 2004, 11:09:55 AM
Quote from: Kerry
Quote from: FlashI removed the other P.O.S. petcock (On/Prime/Reserve) and all the vacuum tubes and put a straight fuel line to my carbs. That is how I know the fuel tank petcock is to blame.
Somebody said something the other day that gave me a new perspective on the whole fuel starvation problem.  The gist of it was something like "When the throttle is wide open there is less of a vacuum to operate the ON/RES diaphragm in the frame-mounted petcock".

If this is true, then the following may NOT be true:
    1) The tank-mounted petcock simply can't pass enough fuel through.
    (Flash, you removed the vacuum system along with the tank-mounted petcock, so how do you know for sure where the problem was...?)
If the fuel from the tank-mounted petcock was able to keep up & the problem was inside the carbs (i.e. float bowl), then wouldn't my fuel line from the tank to the carbs be totally filled with gasoline? What I actually observed (via the clear fuel line) was the meniscus would actually travel from the top down. Wouldn't this mean the gasoline could not get down fast enough?

2) The hoses have a too-small inner diameter to satisy the high-speed fuel demands of our rip-roaring 487cc twin.
I replaced mine with 5/16" ID clear-vinyl tubing from Home Depot; I'd go bigger, but it would be difficult (if not impossible) to affix it to petcock stem

3) The frame-mounted (ON / RES / PRI) petcock simply can't pass enough fuel through.
(It MAY be able to in the PRI position, which is not affected by the presence or absence of a good vacuum.)
I only removed the frame-mounted petcock, not the tank-mounted one. However, I was just thinking: would having the main & reserve stem connected to the carbs via a T-connector somehow be fighting each other? Should I try to cap one of them off? If so, how?
[/list:u]
Can anybody confirm the assertion that
    WOT = significant drop in vacuum?[/size][/b][/i]
I don't think my throttle was totally wide open. Once it happened while I was in 5th gear & another in 6th gear (both while sustaining 80-85 on the speedometer; nothing excessively like doing 100mph)[/list:u]
Now, Ive gotten so paranoid I look down every so often while I'm riding to make sure the fuel line is totally filled with gasoline. So far, it hasn't happened lately.
Title: riding 80-85 on the speedo for 1-2 hours
Post by: ghettorigged on August 08, 2004, 11:15:55 AM
Quote from: mp183You are right about varying the engine speed.  I do that as a matter of principal.  Cuts down on the boredom.  It's also the key to successful speeding on the Thruway.

:cheers:

yes, yes it is. :mrgreen:
Title: Re: riding 80-85 on the speedo for 1-2 hours
Post by: proudlom on August 08, 2004, 01:42:41 PM
Quote from: xaeniacSince the GS500 has a 10% speedo increase can you run the bike at 80-85 on the speedo (really ~75 mph)for about 1.25 hrs without hurting the engine in superhot  humid Louisiana weather?

I had the same question when I first broke my bike in. My brother (he's a mechanic) told me it shouldn't hurt at all.  He said you can run the bike at whatever RPM you want (under the redline) and it should be fine.  8)
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Kerry on August 08, 2004, 07:34:11 PM
Flash!  ("He'll save every one of us!")

Without re-quoting our conversation:
Title: riding 80-85 on the speedo for 1-2 hours
Post by: Flash on August 08, 2004, 08:55:48 PM
Quote from: KerryFlash!  ("He'll save every one of us!")

Without re-quoting our conversation:
    * Oops!  I jumped the gun.  Somehow I got it in my head that you had gone to a Pingel tank-mounted petcock.  :dunno:
-- Boy, do I wish; a couple of members have gone this route, but its like a $90 upgrade

*Are you saying that the changes you made didn't solve the problem?  That would explain your conclusion that the tank-mounted petcock was the major cause.
-- No; so many people complained about the crappy fuel lines & frame-mounted petcock, so I replaced it (apparently it didn't help)

* It's interesting to me that the 5/16" line stays full better than the 1/4" line.  I haven't figured that one out yet.
-- Huh? I increased the ID so as to reduce any possible fuel restriction.[/list:u]
Sorry for the confusion!
No problem :thumb: