EX500 - Production Twins setup

[Kurlon]

Ok, if I decide to start out with an EX500... What are the must do tweaks before it gets raced, assuming it will be run in Production Twins. I'm assuming new rear shock, refresh the front forks, and that's about all I'm allowed to monkey with, yes?

[Pittenger5]

Depends who you ask, some of the top AMs are completely stock so I hear. You can do your forks, rear shock, rotors, but thats about it. No engine work and must have a stock exhaust.

[Kurlon]

So...

Front end:
Fork Brace - $165
Springs - Works Perf Dual-Rate - $140
Cartridge Emulators - $170 (Dunno if these are legal or not?)

Rear end:
Works shock - $600 ($550 + $50 eng charge)

Clipons - $160
Rearsets - $205
Engine Guards - ???
Steering Damper - (Never used one, really worth anything on an EX500?)

Hrmmm... $1440 in bits so far, plus good race rubber, safety wire, blah blah blah

[McBiggity]

skip the fork brace.
let the forks flex, it's how the Ex works.

[Pittenger5]

Yah, I had a brace on mine and damn near everyone told me to ditch it.

[Paul_E_D]

You don't need a brace, or a damper.

Trim the crossover pipe between the exausts about 1.5 inches to tuck the pipes in tighter and gain ground clearance.

Safety wire the bike

HH pads up front

Steel line up front

floating rotor

engine guards

Go racing for 2-4 seasons.

It's not a tinkerers class. It a racers class.

[Kurlon]

Ok, no need for a damper, that makes sense. Not wanting a fork brace seems counter to what I'm used to. I used to ride a V65 Sabre, putting a brace on it made a world of difference in how well the front end tracked, what does the brace do to the EX front end that's counter productive?

On the crossover pipe, do you mean cut out 1.5 inches and weld the remaining bits together, or is there really 1.5 inches of seam hanging down? (If it's the first, I thought you weren't allowed to touch the stock exhaust?)

[Doc]

Buy Mcbiggitys bike.

[Paul_E_D]

It's a clamp that holds the crossover pipes together. Cut one side shorter and coerce the thing back toghether. That doesn't qualify as a mod. If you don't do it, you'll wear right through the pipes once you get faster.

A fork brace might feel better at street speeds, but under heavy cornering forces it introduces torsional stiffness that causes jackhammer like chatter in faster corners.

The only bracing that the EX chasis can handle is frame gussets to stiffen front to back flex. It helps in braking, but isn't necessary with the stock braking system.

You're not going to find out anything new about the EX. It's ALL been tried and for the most part stock works best. Funny, the kawi engineers must get paid to do their jobs.

A penske shock, new springs and valves up front and you're done.

[Kurlon]

Buy Mcbiggitys bike.

Heh, that's part of why I'm figuring out the do's and don'ts on EXs, so I can better evaluate available machines as to how much more I'd need to spend, or how much I save 'cause a given machine has x/y/z on it.

Plus it's nice being able to tell my wife with a straight face that I can really only spend $2k hopping the bike up within the rules.

[Kurlon]

Going to raise this thread back from the grave...

Fork braces on a GS500? Same bad idea? The stock front fender mount/'brace' seems to be prone to coming apart during spills, but is dirt cheap to replace via OEM. My options would be to keep a few spare OEM units and swap as needed, or put in something a little heavier built ala a superbrace.

[Paul_E_D]

The fender mount is the same as a fork brace. In fact, a lot of people (myself included) eliminated the fender on the EX in an effort to reduce chatter. I think adding the brace instead would likely increase chattering troubles. On the GS, though, I don't have first hand knowledge.

[Paul_E_D]

Again, I can't speak about GS's directly, but I've run an EX into the 1:20.8 range and it needs to flex in order to acheive high corner speeds. It may "feel" better with a brace, but when you start pushing the pace, it chatters like a JACKHAMMER in T1 and T9 At Loudon.

[smf]

Going to raise this thread back from the grave...

Fork braces on a GS500? Same bad idea? The stock front fender mount/'brace' seems to be prone to coming apart during spills, but is dirt cheap to replace via OEM. My options would be to keep a few spare OEM units and swap as needed, or put in something a little heavier built ala a superbrace.

just a random thought: tow it to the track race ready (safety-wired, etc). run it. change stuff after you know what it's doing wrong and have run the scenario by people. every rides a little differently. what works for person A might not work for person B

[Honclfibr]

yea that's what I mean. these people weren't ripping through 9 at Loudon. who knows how they were riding & how they decided they needed to machine a thicker brace.

that site is the same reason I have a 93 GSX-R rear shock that only "slightly" rubs the swingarm

Yeah, all of my knowledge about racing an EX has come from ex-loudon racers, as noone else has been foolish enough to ride the EX at such high cornerspeeds as are found by loudon PTWN riders.

Of course, since noone has been foolish enough to ride the GS at those speeds even at loudon, you're kinda blazing your own trail here...

[BMFR6]

from what i understand regarding PTwins, you actually need to find a 5 story building, bring your bike to the top, drop it off the roof, add safety wire and go race. bike will be good to go.

j/k i have nothing productive to add to this conversation besides the fact that everything i hear from the ptwins class, flex is good. not sure about the gs, but i think if you told the grid the ex would flex more if you hosed it down before going out, the nhis water bill would increase

[Kurlon]

Given similar forks, similar geometry, I'm going to assume the GS will respond similar to the EX. Are there many track days before the season starts so I can try and get used to the machine/dial it in BEFORE my first date with Penguin/LRRS?

[Honclfibr]

Well, there's VIR

[Pittenger5]

Penguin is the perfect day to get it sorted.

[Paul_E_D]

There's nothing to dial in!

[McBiggity]

There's nothing to dial in!

get on and ride it!

[Kurlon]

There's nothing to dial in!

I'm a geek, there's ALWAYS something to dial in better!