Hello, I've got a gs500e 1998 and I'm trying to modify it, but I can't find anywhere in the UK that sells parts, can someone point me in the right direction please ...?
I'm looking at adding a oil cooler, bigger carburettors  changing the ignition timing and racing cams and most importantly better brakes for the time being,  I have already lower the sprocket to 14 tooth from 16 , it has a k&n air filter as well as a aftermarket exhaust.
Would anyone be able to suggest anything else??
I'm fairly new to the modify scene so any help would be very much appreciated
Thank you

Take a look here
http://www.gstwin.com/racers_corner.htm

It's a nice list of components you could change, mod, or tune.

I'm pretty new to this myself
but i don't think the older engines accept an oil cooler.
Bigger carbs you say, what the hell for? Have you rejetted the carbs?
Racing cams on a 17 year old bike? I don't think so.
I have a 98 myself and i sent it to the shop for a little work and 3 months later its still in the shop. The cams were toasted and the cam journals were out of round. I had the journals cnc'ed to make them round again and the cams had to be reworked. It cost a small fortune.
Upgrading the suspension is a good mod for a GS. I bought Wilbers front springs and a Wilbers rear shock with 20mm lift. I cant say how it handles cause its still in the box as i dont have the bike back yet. lol
The 14 tooth front sprocket sounds a little small to me, whats the top speed of the bike with a 14? I work on about 10% of speed gained or lost per tooth on the front and 4 teeth on the back gives or takes 10%. Im going to go up 2 teeth on the back so it should drop my top speed by around 5%. This method isn't perfect but it works for me.
As for the brakes I think they are fine for this bike, maybe just try some softer brake pads and/or braided cables.
The timing can be changed for cheap by filing the mounting holes on timing plate thingy to an oval shape. There is a write up around some where. Hopefully someone else can direct you to it. I would but im too stupid. That being said this is a mod im going to try on my GS but im not really holding out much hope of huge power gains. The gs engine is just two big lawn mower engines joined together after all.
Try and cut some weight off the bike. Like the taco, you don't need that. I'm chucking mine out, and the mounting plate for the speedo and taco. The horn, thats gone. All those safety switches on the clutch and foot stand,gone.  Those huge blinkers, gone. I replaced them with tiny little ones. The rear brake arm is steel. Thats no good, get one made out of aluminum. Same for rear sets. The huge mickey mouse ear mirrors, gone. I replaced them with one tiny bar end mirror. Those bits of metal tube for the luggage net, thash them.The list of things to do goes on. Just loose all the crap. But in the end its a GS. Just enjoy it for what it is. If you want go really fast save your cash and buy a decent bike.
Anyways welcome and have fun

There's the timing thingy i new someone could help.

Thank you both posts are much appreciated, with the 14 tooth on its obviously faster off the line, it will pull 90mph and still has 2 1/2 thousand rpm to give in firth gear, I've not yet topped it in 5th gear
Suspension and weight lose would the the two mods that you recommend and changing the timing ??

Suspension has made the biggest difference for me. You could also replace the throttle tube with one from an R6. You'll have to turn your wrist less.

First of all, a gs500 is not a race bike...

It's a nice practical bike that will get you anywhere you want to go as long as you threat it right.

If you want to upgrade the brakes go for steal braided brake lines, they're cheap and they add a significant boost in braking power.
Don't forget to upgrade the front suspension though,  the standard linear front suspension responds very bad to heavy breaking.
Get a good headlight bulb, not only does it make your gs prettier it also makes it safer at night.
This would also be a good time to look at the handlebars, handlebars that are higher up add to your overall comfort especially if you're a shorter rider. (like me)

Most importantly: get a good set of tyres, don't cheap out on those!! Most people use the bridgestone BT045's, i highly recommend them!

Try checking Ebay, Craigslist (do they have that in UK?), Amazon.com, Helperformance.com (for steel braided brake lines), R&G racing (search on google)

I'm not one to come into threads and crush people's dreams. It's your bike. Modify whatever you like on it. Just be sure to know the capabilities of your bike. Managing your expectations of what is achievable is important.

There are old kits around that let you advance the timing, but they are exceedingly rare. You'll really have to search around to find the kit, or DIY, which will take some know-how.

I'm not sure if a 1998 will accept an oil cooler, though I suppose if you know how, and you're rich enough, anything is possible.

You don't need a bigger carb body. Just increase the jet size, but for that to work appreciably, you'll need a hi-flow air filter and an aftermarket performance exhaust, which you've already installed. If you haven't rejetted yet, you REALLY should. The user here The Buddha sells jet kits and can hook you up. Shoot him a pm.

I have no idea about cams for this bike. Finding some will be hard, because who is going to make a performance cam for a GS500?
You could have a custom one machined . . .

Perelli Demon tires

You can swap the front end with for one that fits to a different bike, if you're going to do all this other work, that'd be worth it. Better functionality, and see if you could get a dual rotor design for more powerful braking. You could fab the dual rotor yourself, or find some compatible forks with those already installed.

Steel braided brake lines, get those.

R6 shock.

Cams: the easy (but tough to find) option are from a GR650. I can't remember the specs, but they will fit in the cam lobes.

Carbs: I can say I would try Mikuni VM32's if I had a GS500. Take my word for it though.....swapping carbs isn't a cheap or easy job.

Brakes: Iarn nailed it. A complete front end swap is the way to go for performance. Dual calipers, better suspension, etc can come from a different set of legs.

Timing: you really won't be shattering records with a timing change. But if you can swap cams and fit VM carbs, a timing advance mod is a 15 minute job.

Oil cooler: Jim Knopf makes a cool oil cooler system for the older Twins. Basically flows thru the oil filter & housing.

That being said, the GS500 sold for decades because of its practicality - so keep that in mind. I'm all for modified bikes though man!

Quote from: clarkster1107 on May 12, 2015, 04:06:20 AM

Suspension and weight lose would the the two mods that you recommend and changing the timing ??

I can definitely recommend the suspension change. Go my bike back yesterday and swapped out the front and rear shocks. WOW what a huge improvement.
At the end of the day losing weight from a gs won't really gain you much . But there is heaps of crap on them. I stripped my chain guard and front mud guard today, along with the other junk i mentioned earlier. Damn those front guards are ugly. You can lose the the centre stand too if you like. Then if you want to go really crazy you can drill holes in bits like the rear brake pedal, gear lever and the headlight brackets. Have a good look over the bike there is heaps of stuff to drill. You will only lose a few grams, but it looks cool. Maybe an aluminum rear sprocket. I dont think a gs has enough torque to chew out and aluminum sprocket in a hurry. But then again it might.

What new forks would go on a gs500 ?? As I'm unsure of sizes as I am guessing the bigger the bike the bigger the suspension .....
So what would be a good set of front forks for a gs500 with dual front disks ?? Something like a bandit 600??

Quote from: crackin on May 14, 2015, 02:38:04 AM
At the end of the day losing weight from a gs won't really gain you much . But there is heaps of crap on them. I stripped my chain guard and front mud guard today, along with the other junk i mentioned earlier. Damn those front guards are ugly. You can lose the the centre stand too if you like. Then if you want to go really crazy you can drill holes in bits like the rear brake pedal, gear lever and the headlight brackets. Have a good look over the bike there is heaps of stuff to drill. You will only lose a few grams, but it looks cool. Maybe an aluminum rear sprocket. I dont think a gs has enough torque to chew out and aluminum sprocket in a hurry. But then again it might.

NEVER EVER REMOVE YOUR CHAIN GUARD!!!
If your chain ever breaks, and you have no chain guard, chances are it will hit your back / cut your skin and muscles / amputate your left leg / arm.
You don't want that!

Here Clarkster, have a good look thru this:

http://wiki.gstwins.com/

Tons of info about what can be done with the mighty GS.

Front suspension: Sonic Springs sized for your weight and riding style
Rear suspension: Katana 600 shock replacement

Both of those mods cost me under 100 bucks.  Both made an appreciable difference in handling for me at 6'2" 200 pounds.  The suspension upgrades are the low hanging fruit for improving the GS IMHO.

I put a Yoshi on mine, it made it a little more responsive to the throttle, but mostly for the sound and ridding myself of the looks of the stock pipe...this mod can help when it is done with an aftermarket air filter and a re-jet.

NEVER EVER REMOVE YOUR CHAIN GUARD!!!
If your chain ever breaks, and you have no chain guard, chances are it will hit your back / cut your skin and muscles / amputate your left leg / arm.
You don't want that!
[/quote]
I have dropped (and seen dropped) a lot of chains over the years and have yet to be hit by one. I'm sure it could happen, but generally they just fly of and smash the clutch rod and engine cases regardless if you have a chain guard or not. So i would say chances are it will smash your engine and not hit you at all.
I have never ever ever seen a chain snap in my life, they either come of the rear sprocket from being too lose or the joining link drops out. I have an O ring chain on the gs and it would be lucky to stretch it let alone break it.
I take the information on board, but the guard won't be going back on until the local copper tells my to put it back on.

OP I think what you're looking for is a GSXR600... 

One thing I would love to know is how well those cams (or that 650 head) works when installed on the smaller twins. I'm told the cams have more lift and less duration. How much, if any, to I lose on the top end, and is there a useful gain in the mid-range. Does the 650 head drop on, and is the chamber volume large enough to lower compression, or would it not lose compression on top of my 45O with it's taller than Tempter piston domes?  I just got to know, boys! I've got a "Tempter" motor and an extra "Tempter" head with cams. Do those hollowed out cams let a motor rev faster?

BTW, the old 450 frame looks like there's lots of head room should I want to put the Tempestuous motor in there. Deck that motor
put on some Sudco carbs and maybe have a tuner open the ports a little and I THINK I might get a 60 HP GS 450. Is this just another delusional episode? Would these mods work? So many questions!!

Quote from: clarkster1107 on May 12, 2015, 01:23:01 AM
Hello, I've got a gs500e 1998 and I'm trying to modify it, but I can't find anywhere in the UK that sells parts, can someone point me in the right direction please ...?
I'm looking at adding a oil cooler, bigger carburettors  changing the ignition timing and racing cams and most importantly better brakes for the time being,  I have already lower the sprocket to 14 tooth from 16 , it has a k&n air filter as well as a aftermarket exhaust.
Would anyone be able to suggest anything else??
I'm fairly new to the modify scene so any help would be very much appreciated
Thank you

You wont find any parts for it in the UK, the GS5 was never a sports bike (despite the pretentious appearance and marketing blurb of the F). It was never that popular, and the model has been dead for 10 years now. Owners tended to buy them to learn on and then quickly move onto something more exciting, desirable and modern.

They don't tune easily but you can get a few more hp out of it by working on the breathing and timing and you can improve the handling and braking to a degree but they wont be substantial gains and they certainly wont put it up there with the true sports bikes. It is generally accepted that putting the money into a better bike offers more value.

If you want to get into serious modding and chasing performance gains get a 600 Bandit. There is a huge range of custom and performance parts available for these models and your options are practically limitless. Decent ones start around £1k and there is plenty of choice.


Oh.....and don't even think about taking the chain guard off, apart from the safety implications and the MOT issues you will save more weight spending 15 minutes sat on the toilet before taking the bike out 

Quote from: GSteve on April 10, 2016, 02:03:00 AM
One thing I would love to know is how well those cams (or that 650 head) works when installed on the smaller twins. I'm told the cams have more lift and less duration. How much, if any, to I lose on the top end, and is there a useful gain in the mid-range. Does the 650 head drop on, and is the chamber volume large enough to lower compression, or would it not lose compression on top of my 45O with it's taller than Tempter piston domes?  I just got to know, boys! I've got a "Tempter" motor and an extra "Tempter" head with cams. Do those hollowed out cams let a motor rev faster?

BTW, the old 450 frame looks like there's lots of head room should I want to put the Tempestuous motor in there. Deck that motor
put on some Sudco carbs and maybe have a tuner open the ports a little and I THINK I might get a 60 HP GS 450. Is this just another delusional episode? Would these mods work? So many questions!!

Steve, I've seen all kinds of madness done with the Suzuki twin motors (400, 425, 450, 500, and 650). I'll find some links for you to dig thru later today, but in the meantime I can tell you that a GR650 engine does NOT fit in a GS450 frame.

Thanks Big Rich!
    I've never seen anything on GR650 cams, so anything you dig up related to them would be quite a find to me!

So far as putting a GR650 motor in a GS450 frame, Now you really have me curious. I stand warned. Of course, you can put a Helicopter motor in a submarine with enough time and money. This is not to say I have much of either, but, damn! It looks like it would! I can only imagine something like inability to align front and rear sprockets, or maybe a wrong angle on the pipes, and that looks like more of a problem with the GS500 frames. I'm going to look at it with a tape measure this time. That alone might save me some tears!

Glad you bumped this Steve! I got busy the other day and forgot (sorry bud). But here is the "other" GS Twins wiki:
http://www.thegsresources.com/_forum/showthread.php?205995-GS-Twins-Wiki

And I can't find the other threads I was looking for.....but here's a link to the GSR's section on the older parallel twins:
http://www.thegsresources.com/_forum/forumdisplay.php?141-2-Cylinder-(Twin)-Engine-Drivetrain-Clutch

When I was working on my 450, I looked at one of my 650 engines with the same thought. Can't remember exactly how I got to the conclusion that it wouldn't fit, but I think I measured from the bottom engine mounting bolt to the top of the cylinder head. The 650 engine is about 1.5" taller, and the 450 frame just didn't have that kind of space (this is all from memory, so take with a grain of salt of course).

I do remember that after measuring the space, I decided it wasn't worth the effort to physically attempt to stuff the 650 motor in the 450 frame. But if you want to try it, I applaud you!