Figured I'd start a post covering my build progress on my 93 GS500E as I turn it into a proper road race machine.
For those unfamiliar with the 'Production Twins' class run by LRRS at Loudon NH, in a nutshell it's production bike racing for two cylinder machines, 650cc air cooled, 500cc liquid. The dominant machine by sheer numbers is the venerable EX500. Occasionally someone will show up with a Ducati 620 Monster or Supersport, but thats rare. For 'mods' I'm allowed to respring and add emulators up front, and replace the rear shock. After that, I'm only allowed safety modifications, so turns signals are to be removed, safety wire, etc. I have to retain the stock headlight bucket (Need to see if I can gut it though.) and stock exhaust. I'm allowed to update and backdate within the model run, and I've already cleared using GS500F parts as it's essentially the same bike.
The victim in this case is a 1993 GS500E I purchased from a friend. She bought it as a learner machine, used it for a couple years, and finally gave up on it when it started eating coils like candy. I don't know it's prior history.
When I got it, it had clubmans installed backwards so they resembled standard bars, one coil was bad. Further diagnosis found one side of the CDI was shot, as was the regulator/rectifier, which I think started the bike's electrical woes. A little ebay work later I had a new CDI, a generic regulator/rectifier has my charging system sorted. The clubmans aren't wide enough to clear the upper clamp when I tried mounting them correctly, so then end up being rotated to far back, completely impractical. I still rode it to work to see how it went, and other than killing my wrists, the only observed issues were almost non-existent brakes, carbs could use a good cleaning, and when warm there is a slight knock from the head. Oh, and it has classic GS500 weeping head gasket syndrome.
The bike has since sat, as I haven't had time to work on it, or space given the horrendous weather we've had. I have been busy in other ways though...
I bought a set of used Woodcraft rearsets, indirectly through a member of the forum. (l3uddha bought them and then sold them to me after buying a Triumph.) Not finding any deals on clipons, I went ahead and bought a set of Woodcrafts new. EBC HH pads are on order, as is a new front rotor. Suspension bits will be on order shortly, Works in back, Racetech up front.
I need to find a new(er) set of forks, or at least upper tubes, as mine are pitting. I'd like to find an F exhaust system as they are reputed to have larger headers than the E's. Plus I need to invest in safety wire and drill bits... lots and lots of drilling and wiring to do.
My first opportunity to run the bike on the track is April 15th, so things are going to be going nuts for me shortly... : ) I'll try and get pics as I go.
Spoke to David Johnson via email, I've now got a couple additional items to track down, a good fork brace (I see one in the For Sale section) and a 96 or later front caliper. Add a set of preload adjusters for the forks, and I should be in good shape.
Are you allowed to rejet the carbs and add a K&N lunchbox?
I can rejet, but I have to retain the stock airbox and filter.
You can always richen it up and blind them with the black smoke. :laugh:
Quote from: Kurlon on March 10, 2008, 06:21:54 PM
I can rejet, but I have to retain the stock airbox and filter.
Stock airbox with drop in OEM replacement Air filter.... like a K&N drop in minus restrictor plug :icon_mrgreen:
Awesome, I'm looking forward to the progress :thumb:
I heard Loudon is a crazy track...something about a bowl which has you looking up over your shoulder as you round the turn?
Quote from: badguy on March 11, 2008, 09:36:08 AMI heard Loudon is a crazy track...something about a bowl which has you looking up over your shoulder as you round the turn?
Yup, 'the bowl' is a near 180 degree banked turn. You enter it coming down hill at a good 15% grade or so, aiming to be moving left, crossing the middle of the track as you enter the turn. Then it's a hard left, down the side of the track into the middle of the turn, at which point you start looking up, about at the limit of how far your helmet will let you crank your head back as you climb up a new, sligthly steeper grade than you came down in on as you complete the second half of the turn, throttle up the hill for a lil kick right, then back down the hill for a fun 90 right that brings you back onto the NASCAR oval. : )
Looks like a weird line on paper, feels incredible the first time you get it somewhat right, you can carry crazy speed though it with the right line. Given my competition has 10hp on me on average, thats one of the areas I hope the GS's superior geometry gives me an edge, along with the few hard braking points. (EXs have the same caliper as the pre 96 GSs, so by upgrading I can run better pads, and have more contact area, so I should be able to late brake them if I grow big enough stones...)
Fork brace and rotor covered on their way from a forum member. Still gotta do a bit more research on the E to F exhaust swap and if it'll actually net me anything.
Sounds like fun! Keep us posted. :icon_mrgreen:
I'd like to hear more about how the class is set up, costs and whatnot. Unfortunately though, I'm too far away to play. :cry:
Who runs the local series in your area? I know WERA has a bunch of GS500s running around, and they're allowed more leeway in their builds compared to PTwins in NH.
Quote from: Kurlon on March 10, 2008, 06:21:54 PM
I can rejet, but I have to retain the stock airbox and filter.
I've got a unifoam if you can run that that I'll sell you cheap.
Fork brace and rotor inspection cover arrived, both are billet art.
I also have a new 'todo' item to investigate for the build... frame sliders. One person racing in WERA has mounted a set on the main frame rails, right under the tank. Looks like he found a spot where he could put in a cross brace between the rails... looks slick and the report is it worked well the one time the bike was down. :P
A new caliper (96+ style) is on order, new rotor arrived from EBC and it looks killer.
I need to settle on engine guards too, completely spaced on those.
Bombadillo: I dunno how strict they're going to be on filters yet, so for now I'm going to put a new OEM unit in I think.
Does the air filter have to have the paper element in it?
One thing about the exhaust... grind out the weld on the inside of the header at the mounting flange at the head. I removed at least 1/16" on the ID on each of mine. It may not be much but any extra flow would help.
Quote from: Kurlon on March 18, 2008, 10:49:30 AM
Fork brace and rotor inspection cover arrived, both are billet art.
I also have a new 'todo' item to investigate for the build... frame sliders. One person racing in WERA has mounted a set on the main frame rails, right under the tank. Looks like he found a spot where he could put in a cross brace between the rails... looks slick and the report is it worked well the one time the bike was down. :P
A new caliper (96+ style) is on order, new rotor arrived from EBC and it looks killer.
I need to settle on engine guards too, completely spaced on those.
Bombadillo: I dunno how strict they're going to be on filters yet, so for now I'm going to put a new OEM unit in I think.
For case guards check out http://www.mcenterprises.com/ for a set for $40. They work great, and are a steal at $40.
I want pics. :icon_mrgreen:
No pics till it's at least de-greased. : )
If the weather cooperates, it comes out of storage Saturday for a quick trip to the local car detailer. It'll get a quick cleaning with a heated pressure washer, then back to the shop for an eval session. I'll try to get some pics if all goes to plan to show you the 'before' condition.
Be super carefull with the pressure washer, alot of the bearings are not sealed enough to prevent high pressure water from getting in there.
Lovely, thanks for the heads up! I'm hoping that the heat will do the majority of the work rather than relying on the pressure, but we'll see what happens.
http://www.x386.net/TTR/media/GS500E/032208-Initial_Build/HPIM0360.JPG
http://www.x386.net/TTR/media/GS500E/032208-Initial_Build/HPIM0361.JPG
As promised, pics. This is just after cleaning it today. Spotted two things of interest; the front rotor is an EBC unit, and someone rigged their own chain guard out of metal... thats going to go.
Oh, and I'm missing the left hand Suzuki emblem. I'm half tempted to get a big round puck of Delrin and bolt it in place instead... :P
dumb question ( and lsightly intoxicated,so bear with me) but when you set up for racing, are you supposed to safety wire, and if so, how? ty ahead of time :cheers:
Yes, for racing I have a whole crazy long list of things that must be safety wired, along with the general rule of thumb that if I would be annoyed to have it rattle off at speed, it should be wired. So just about every nut and bolt on this thing will be wire tied in one way or another when I hit the track in April.
There are lots of safety wiring guides online. The general idea is you drill your victim, as well as a nearby spot to use as an anchoring point. Loop the wire through your new hole, and then twist the wire so there is no slack, loop through the anchor hole, twist out any slack, and snip off any excess. You want the wire pulling the victim such that in oder for it to undo itself, it's going to have to pull against the wire.
Way back when I raced go karts I spent a week drilling nuts and bolts for safety wire.It's a pain in the a$$.
Quote from: ben2go on March 23, 2008, 10:37:49 AM
Way back when I raced go karts I spent a week drilling nuts and bolts for safety wire.It's a pain in the a$$.
mmm, more 2 1/2" stainless bolts being safety wired come to mind. ouch. stupid props. stupid ships.
haven't safety wired anything on my gs, but then i'm not going fast on a track either :D
speaking of safety wire, i was curious if you were going to be using your stock clutch lever safety switch, the little bugger mounted under the clutch perch.
mine broke, i was being dumb :mad: and if you were not going to be using it i would purchase it from you :dunno_white:
The safety switches are like $5.00 from www.bikebandit.com, Ron Ayers, ect ect
Quote from: TANNER on March 23, 2008, 06:43:21 PM
speaking of safety wire, i was curious if you were going to be using your stock clutch lever safety switch, the little bugger mounted under the clutch perch.
mine broke, i was being dumb :mad: and if you were not going to be using it i would purchase it from you :dunno_white:
Amusingly, unless it can be proven it's a safety hazzard, I think I have to retain it for the production class.
Fork springs and emulators arrived today, along with brake pads. Put in an order for a Works Perf shock, fully adjustable with a ride height adjuster so I can dial in the twitchyness. : )
With the fork bits here I can start working on the front end, maybe Saturday?
Build update - First snags encountered. The used Woodcraft rearsets I got fit, and move the pegs back a good 1.5 inches, which is good. They also lower the pegs an inch, not so good. So, while CBR900 fitment rearsets do in fact mount on a GS500E, they are no good for racing. Second snag, while cleaning 15 years worth of road debris, dirt, and chain lube from behind the front sprocket cover, I developed a gas leak. It looks like it's either a line cracking, or the vacuum petcock on the tank. Guess it's good that it happened now vs on the track though.
So, all I accomplished today was cleaning out the buildup behind the sprocket cover, determined both my sprockets are junk, and mounted a billet ignition rotor cover to give it some crash protection.
Are these Woodcraft rearsets made for the GS or are they from another bike? Mine raised the pegs and I never had a clearance problem.
These were for a CBR 900. I got them used via this forum hoping to save some over the cost of new... but that didn't quite work out. I will at least be able to swap over the shift linkage and brake pedal though, so they aren't a total loss for me.
You could make plates out of aluminum to raise and move them back.The weight penalty wouldn't be noticed in any way.Cheaper than another set of rear sets.
I don't have any aluminum handy, and that'd put them too far back. Given it's a race bike, I'd rather not make a large lever out of the assembly, having my rearset mounts ripped off the frame would be a bad way to end a weekend. : )
i know this thread is way old but i was just wondering what kind of handlebars/forks do you have on there? i recently acquired a gs500, i love the bike but i want a little more aggressive stance. not finding much on the web for what i'm looking for........
I'm using the stock forks with new springs, cartridge emulators, and Woodcraft clipons. The forks are raised a touch in the clamps. I'm hoping to get my damping rods reworked so I can stop using 30w sludge for fork oil to get any damping out of them.
Quote from: Canonball on December 27, 2008, 04:45:44 PM
i know this thread is way old but i was just wondering what kind of handlebars/forks do you have on there? i recently acquired a gs500, i love the bike but i want a little more aggressive stance. not finding much on the web for what i'm looking for........
I have an 06 GSXR-600 front end/forks on my racer. Stock clipons. Works a treat.
If keeping stock forks, woodcraft or vortex clipons are the way too go. I love my woodcraft rearsets.
Quote from: Kurlon on December 28, 2008, 02:11:05 PM
I'm using the stock forks with new springs, cartridge emulators, and Woodcraft clipons. The forks are raised a touch in the clamps. I'm hoping to get my damping rods reworked so I can stop using 30w sludge for fork oil to get any damping out of them.
You put the cartridge emulators in there right? If you did you should have drilled a bunch of holes in the damper rod(as specified by race tech), since the damper control is via the cartridge emulator.
Quote from: coll0412 on December 29, 2008, 02:43:31 PM
Quote from: Kurlon on December 28, 2008, 02:11:05 PM
I'm using the stock forks with new springs, cartridge emulators, and Woodcraft clipons. The forks are raised a touch in the clamps. I'm hoping to get my damping rods reworked so I can stop using 30w sludge for fork oil to get any damping out of them.
You put the cartridge emulators in there right? If you did you should have drilled a bunch of holes in the damper rod(as specified by race tech), since the damper control is via the cartridge emulator.
The compression damping is controlled by the emulator, and it's working fine. I can get proper compression using the emulator and 10w oil. It's the rebound that needs to be reigned in, only way to get decent rebound control is with 30w oil. The fix, rework the rebound ports on the damping rods.
i like the clubman style handle bars, i found some here: http://www.airtech-streamlining.com/suzuz/GS500Titan.htm, anyone have any experience from this company?
p.s. not tryin to whore the post
Can you elaborate on jetting for Loudon?
And you had the forks brazed and drilled by KB? You know what size holes? And is this compatible with a non emulator setup?
Quote from: Kurlon on December 29, 2008, 02:58:57 PM
Quote from: coll0412 on December 29, 2008, 02:43:31 PM
Quote from: Kurlon on December 28, 2008, 02:11:05 PM
I'm using the stock forks with new springs, cartridge emulators, and Woodcraft clipons. The forks are raised a touch in the clamps. I'm hoping to get my damping rods reworked so I can stop using 30w sludge for fork oil to get any damping out of them.
You put the cartridge emulators in there right? If you did you should have drilled a bunch of holes in the damper rod(as specified by race tech), since the damper control is via the cartridge emulator.
The compression damping is controlled by the emulator, and it's working fine. I can get proper compression using the emulator and 10w oil. It's the rebound that needs to be reigned in, only way to get decent rebound control is with 30w oil. The fix, rework the rebound ports on the damping rods.
Jetting is jetting, Loudon isn't significantly high up so if it works in New England it'll get the job done there.
On the damping rods, I haven't had mine reworked yet.
For some reason on some other forum I was under the opinion that you might have deviated from what is on the wiki. So you are still running sludge in the forks, huh? Maybe I want 20W-50 for when the forks heat up =)
Oh, yeah, I'm leaner than the wiki suggests. I've got to pull my notes to find the exact setup I've got at the moment. I've been fighting a horrible midrange hole, and think I've got a good bit of it eliminated finally, but now that I've got my shift points refined a bit I don't find myself letting the revs drop to that range.
You mentioned at the beginning of this thread that there was a knock from the motor, I have a similar issue and it turned out to be the counter balance shaft bearings, dont know if its still an issue for you but if your still racing it you may want to investigate it further.
Bonesaw
Quote from: Kurlon on December 29, 2008, 02:58:57 PM
The compression damping is controlled by the emulator, and it's working fine. I can get proper compression using the emulator and 10w oil. It's the rebound that needs to be reigned in, only way to get decent rebound control is with 30w oil. The fix, rework the rebound ports on the damping rods.
HOLY COW RESURRECTION! :icon_razz:
Kurlon I closed shut the rebound holes on the damping rods a couple days back.
Difference? Minimal to none. it seems 30w is the way to go..
Wow?! Those forks should come to a complete stop with no rebound holes. Sounds like there is some serious slop in the bushings too then? My bike has since gone back to being a street mule with my wife the primary pilot so I haven't bothered to chase the forks further. If I do anything I need to go to lighter springs for her next, it's a bit nervous on rough pavement with all that road race preload in place.
Yeap, too much slop, and considering what sportrider says, it seems the GS hasn't got a very controllable leakage.
"On the rebound stroke (figure 2), chamber B is getting smaller and the floating check valve is closed. The fluid escapes from this chamber two ways: through the rebound hole in the damping rod and through controlled leakage between the damping rod and the check valve itself." - http://www.sportrider.com/tech/146_9502_tech/index.html
(Of course, considering the rebound hole was about 1,5mm - 2mm in diameter, it ain't no mystery there is no apparent change in damping.)
Congrats on the wife! Lighter springs and less damping all around will surely make a comfortable ride!