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GS500 DYNO SHEETS!!!

Started by starshooter10, January 06, 2009, 11:55:09 PM

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starshooter10

okay so i could never find them so ill post up a couple!!!

here's my 92 GS with ~26000 miles drilled out the pipe and had WAY oversized jets and a uni drop in:
(i also beat the living POOP out of this bike, also my bike stuttered a bit on the dyno... so the powerband is very rough)
thats 33.61HP and 23.06 TQ




here's a 07 GS500F (with 500 miles)
ridden NICE
peak was 36.19HP and 24.44 TQ





*Keywords so you fools can use SEARCH!!!!*
*GS 500 500F 500F GS500 GS500E GS500F*

all done =-P

ohgood

cool. looks like the 3 circuit carbs are a good deal smoother to ride- assuming the later bike wasn't molested to achieve that nice, smooth curve.

were you changing gears at the beginning on your bikes' run, or was it just that rough ?

thanks for the graphs ! :)


tt_four: "and believe me, BMW motorcycles are 50% metal, rubber and plastic, and 50% useless

gsJack

Here's dyno curves for Annie's GS (forum founder John's wife) which is linked off gstwins.com front page.  It has V&H exhaust, carb jetting, and K&N filter changes:



Here's dyno curves for a friend's 02 GS500 which he had jetted for winter use, no other mods:



It has power peak at 8500 rpm where mag test reports always show it in road tests.  Your peak looks a bit lower than this.  I saved a small one from a mag EX/GS comparo test that looks same with peak hp @ 8500 if you can read it:



Curves show how Annie's modified GS has power extended beyond 9k rpm with about 3-4 additional hp over stock.  Not much sense in revving a stock GS beyond 9-9.5K unless you want to just pump out a lot of extra oil after you get some miles on it.   :icon_lol: :icon_lol:

407,400 miles in 30 years for 13,580 miles/year average.  Started riding 7/21/84 and hung up helmet 8/31/14.

starshooter10

yeah i've learn that the sweet spot seems to be from 7 to about 8.5 or 9

i rarlwy reved over that make (unless i was hotrodding in a turn... then im reluctant to shift)

but even then i would go past 11k

cosmiccharlie

Quote from: starshooter10 on January 07, 2009, 09:24:55 AM
but even then i would go past 11k
That is why your engine destroyed itself.

natedawg120

Quote from: cosmiccharlie on January 07, 2009, 10:07:19 AM
Quote from: starshooter10 on January 07, 2009, 09:24:55 AM
but even then i would go past 11k
That is why your engine destroyed itself.

+1, valves float a little past 10k and max power is at around 9.5k so there isn't really a reason to run past 10k.
Bikeless in RVA

The Buddha

Valve float and piston valve contact is very unlikely. It will make a horrible noise and not lose power and start to die, it will lose power and make noise and die spectacularly in 1 instant.
I have another theory.
You may have had wall lubrication washed off by the overly rich gasoline in flow. Wall to piston seize can happen slower, a little as it gets more heat from lack of oil on the wall.
Cool.
Buddha.
-----------------------------------------------------------------
I run a business based on other people's junk.
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starshooter10

err

i wouldnt rev to 11...

though going to 10 wasnt something that never happened...

though it did happen...

and budda your probally right as it was about time for an oil change... and it was RICH

gas = solvent =-(

aaronjosephward

#8
heres one
only mod was a drilled exhaust.

black and silver twin



Here's the dyno for my 07 GS500F with 2000 miles on the odo. the only things done to it are PAIR system removed, NGK iridium plugs, and castrol rs r4 rt full synthetic 5w-40 motorcycle oil. the graph doesnt show the afr numbers (pink line) but it was around 13:1, super lean.
07 black GS500F; fenderectomy, NGK DPR9EIX-9 plugs, 15T sprocket, Jardine exhaust, K&N lunchbox, 20-62.5-152.5 jets 1 washer, timing advance 6*, flushmount signals,Tommaselli clipons over tree, sv650 throttle, 20w forkoil, sport demon tires, Buddha fork brace, Goodridge SS lines, double bubble

trx440r

What's the most you can get out of a GS when you throw some money at them?  Just curious.

.

fred

Quote from: trx440r on April 12, 2009, 07:34:53 PM
What's the most you can get out of a GS when you throw some money at them?  Just curious.

.

Probably about 39.4 horsepower...

dwkfym

Just a note for those who don't know already

Dynos are not all the same, especially between different manufacturers, and more so between dyno types (inertia dynos, brake dynos, etc)

trx440r

Quote from: fred on April 12, 2009, 07:39:47 PM
Quote from: trx440r on April 12, 2009, 07:34:53 PM
What's the most you can get out of a GS when you throw some money at them?  Just curious.

.

Probably about 39.4 horsepower...


Are there no larger or higher compression pistons available?  Stroker kits?  Anybody run FCR 35's?

I got 52hp at the wheels with a 400ex quad that was massaged to 465cc.  Certainly You can 60+ out of a GS.

That being said, I am going to do a stock spec valve job on mine and new pistons, then leave it alone.


.   

tulebox

QuotePAIR system removed
Can you elaoborate on this mod? what gains are there, I haven't heard of it.... thnx
Calling an illegal alien an 'undocumented immigrant' is like calling a drug dealer an 'unlicensed pharmacist'
'08 gs500

lamoun

Quote from: tulebox on April 13, 2009, 06:14:28 AM
QuotePAIR system removed
Can you elaoborate on this mod? what gains are there, I haven't heard of it.... thnx

You just lose some weight.  :D

The system injects air in the exhaust ports, making the gases burn better.

tulebox

Calling an illegal alien an 'undocumented immigrant' is like calling a drug dealer an 'unlicensed pharmacist'
'08 gs500

bill14224

If you read David Johnson's "Racer's Corner" he goes into what it takes to get more power from a GS.  The short answer is pipes, jets, and no airbox gets you a few more HP.  If you want to get into the 50's it takes advancing the timing, racing cams, porting, polishing, and milling.  You can't get 60 HP out of a GS 500 unless you spend what Dave calls "a Subaru".
V&H pipes, K&N drop-in, seat by KnoPlace.com, 17/39 sprockets, matching grips, fenderectomy, short signals, new mirrors - 10 scariest words: "I'm here from the government and I'm here to help!"

fred

Quote from: lamoun on April 13, 2009, 07:52:58 AM
Quote from: tulebox on April 13, 2009, 06:14:28 AM
QuotePAIR system removed
Can you elaoborate on this mod? what gains are there, I haven't heard of it.... thnx

You just lose some weight.  :D

The system injects air in the exhaust ports, making the gases burn better.

The system injects air into the exhaust to burn more hydrocarbons as they go out the tail pipe. It is for emissions. I can't imagine that the weight savings is really worth anything on the GS though. If you want your bike to weigh less, start exercising. You are the single heaviest component of the bike and, if you live in America, there is a 65.5% chance that you are overweight...

black and silver twin

I removed the PAIR system for two reasons. First because Im 6' tall 170 lbs with 8% body fat so I cant really lose any weight, so dropping weight from the bike is obvious (Im also doing A V&H which is significantly lighter). And second, I work at INTENSE Racing modifying cars all day, I HATE superfluous stuff that can only hurt performance. If somthing is free, easy, and can only help why not do it? I know it's not much and probably not noticeable but I now have peace of mind, STOCK really does keep me up at night. Seriously. 

Also, I forgot to mention that just after the dyno I topped out the bike at 114mph on a dead straight, flat road in new albany ohio. Not super fast (Ive taken my car 140+), but scary on a bike. Then my friend passed me going 150 or so on his 636. Fun day 8)
07 black GS500F; fenderectomy, NGK DPR9EIX-9 plugs, 15T sprocket, Jardine exhaust, K&N lunchbox, 20-62.5-152.5 jets 1 washer, timing advance 6*, flushmount signals,Tommaselli clipons over tree, sv650 throttle, 20w forkoil, sport demon tires, Buddha fork brace, Goodridge SS lines, double bubble

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