Mods thread: Hyosung GT250R [Archive]

EnzoYug

18th December 2007, 15:54

**UPDATE! So you've found my thread! Good job - well before you get too into it let me stop you right there. "Evey" as she's called - has been binned. Pretty hard too. Scenic Drive (auckland) chewed her up real bad so the 'Mod' thread is about to be replaced with a re-build thread. The main reason to read this thread is for info on modding your Hyosung CDI unit for better response / eliminating the famous 3'rd gear flatspot..**

This thread is all about my sexy GT250R, or at least it will be - I'm starting to customise it now that I've hit 8,000k without the slightest problem. So here's a list of what I've done so far and what needs doing. I'll update as I go.

What I want is any advice other bikers, particularly any Hyobag owners might have on these:

Mod 0: New tyres. After a 160kph double blow out (it's ok, i threw myself into the road and caught the bike with my crotch) :P I replaced the shitkos with some GT501 Radials. Great tyre. DONE!

First mod: loose that can! I've picked up a Screaming Demon straight-through pipe from aussie, in comes in shiny carbonfibre finish and should give the bike some roar. DONE!

Second: New air filter. BMC make a top-quality air filter for the hyosung so I'll chuck one of those in to help out with the inflow (since outflow is already sorted). PENDING! (waiting on parts)

Third: Get that bitch rejetted! She'll be running lean as a kenyan with the new filter & can so i'll get the boys at Red Baron to fiddle with her bits till she's puring. Otherwise I imagine that she'll start hurting - fast. PENDING 8000k SERVICE!

Fourth: Bling her out. New high-wattage head lights, clear-style indicators (2008 hyosung ones, fuck this microindicatorcrap - i like em CHUNKY!), Gold anodised tire valve caps & gear/clutch levers, and some custom decals on the front fairings. LIGHTS DONE - INDICATORS DONE

Five: Speedo healer. I know the speedo's out, but the question is - by how much? I'll pick on of these up and slap it in. Just hope it's easy to wire.

Six: Fit a (fake) alarm. Who the fuck wants to steal a Hyobag? I don't know, and frankly I don't like using an alarm anyway - I've got a disc lock, and a baseball bat. That's enough for me. So i'll wire up a flashing led to the dashboard. That should do the trick.

Seven: Custom seat cover. I met a guy, who knows a guy who's dog does upholstery. Hopefully I can rip the pleather off my seat, put some nice 'soft' foam in their and get it sewn up for $200 to $400 less than the $300-$500 odd bucks everyone else wants for the pleasure of doing it.

Eight: Tail hugger & Tail tidy unit. Rip off the shovel on the back of the bike and enjoy all the road shit leaving a stripe up my back. Then get a tail hugger installed along with chain guard to match - for ideas see Warlock's GT250R.

Nine: Braided brake lines along with scintered pads. 0-100 is good, but I think the faster I can get the back to zero again is more important. New brakelines and pads are the last part of the plan.

Ten: Enjoy!

So. That's the plan, in no particular order - just as I can afford it. Any thoughts comments or gifts of money?

deanohit

18th December 2007, 16:16

Sounds good mate, heres some links off http://www.korider.com/forum/index.php, a Hyosung forum site:
Brake Pads, Clip-ons,screens,lowering kit,Micron exhaust for 650, tank protector, rims, exhaust, rearsets....too many parts to list here- https://www.fresnomotorsports.com/catalog.shtml

Race Fairings- http://www.time-to-ride.com/hyosung_racing.html

Aftermarket screens- http://www.eaglescreens.com.au/

Center stand & exhaust & racks( great prices on exhaust! )- http://seaies.com/koreabikeparts/koreanparts.html

Great looking fender eliminator/ undertail ( pre-order )- http://www.eliminators.biz/

Rear Hugger and Seat cowl -listed for gt650 ask for david- http://www.streetfightersbydesign.com/streetweb/skidmarx_page/skidmarx%20home%202.htm

Braided brake lines & Fender eliminator- http://www.emigroup-us.com/frentubo/ftp_hyosung.shtml

Jet kits & lowering kits- http://www.hardparts.info/

Aftermarket air filter- http://www.bmcairfilter.com/infoBK2.asp

Exhaust brackets,sprockets, & Pistons (this place may be down for good)- http://www.hyosungracing.com

Exhaust cans down under- http://www.megacycle.com.au/

More Cans down under- http://www.staintune.com.au/

K&N oil filters- http://www.knfilters.com/search/applications.aspx?Prod=KN-131

Fender eliminator- http://www.epfguzzi.com/hyosung/

Frame Sliders- http://www.rg-racing.com//showproducts/Crash_Protectors/Hyosung_Crash_Protectors/GT250R_Crash_Protector.aspx

another fender eliminator- http://www.rg-racing.com//showproducts/Tail_Tidies/Hyosung_Tail_Tidies/GT250R_Tail_Tidies.aspx

More Exhaust & stock body parts- http://www.richardhyosunggvgt.com/cometgt125250650rs.htm

More sprockets and fork seals- http://www.hyosungperformanceparts.com/

Tail riser- http://www.bikefarmmv.de/EN/tail-riser/index.php

chain guard- http://www.bikefarmmv.de/EN/chain-guard/zeige_artikel.php?fid=200928

Good luck with your project mate! :niceone:

HungusMaximist

18th December 2007, 16:56

You know, all that mod is like x-mas presents for your family & relatives for the next 5 years.

Ah, why don't you just buy another bike with it all kitted out?

But never the less, if you head up my alley there's certainly a cold one waiting for you. :yes:

EnzoYug

19th December 2007, 00:24

Sounds good mate, heres some links ....
Good luck with your project mate! :niceone:

Ho-leee-shit. That's a great place to start. Ha ha ha ha, I'm in heaven. Thanks mate, I've got as much bling as possible flinging your way now.

Woot! You're a champ!

shaneh

19th December 2007, 20:57

nudedaytona

19th December 2007, 21:06

Faaark, mine does 140 in 3rd or 4th without really trying, and I haven't even hit the powerband yet

RC1

19th December 2007, 21:12

Faaark, mine does 140 in 3rd or 4th without really trying, and I haven't even hit the powerband yet

and tops out at??? all of 210?? :zzzz:

disenfranchised

19th December 2007, 21:15

Just one question, how on earth do you get your bike up to 160 km/h ?
I can't get more than 130 km/h out of mine (naked, full throttle, chest on the tank in top gear). Is my bike rooted or am I too fat (75kg) ?

I'm also on the naked, and I can reach 140 on a long straight.
I never even get down that low and I weigh 95kg.
Maybe you're changing to 5th too early...it's more of an overdrive gear

Weaver

19th December 2007, 21:26

Lying down flat on my tank and only weighing 68kgs the best I have managed is 158kms. However mine is the GTR and the speedo is out by about 10%. Probably could do better with a longer straight and a tail wind.

I'm going to make mine stop faster rather than make it faster over-all. Braided lines and better pads.

disenfranchised

19th December 2007, 21:32

So. That's the plan, in no particular order

That's a good list.

I've already added the extra front brake, and the SD exhaust.

Next I wanted the hugger and a belly pan.....just for the look.
Plus a fender eliminator...but not that one you can buy...the indicators look a bit suspect legality wise...this seemed like a good idea tho
http://www.korider.com/forum/modules.php?name=Forums&file=viewtopic&t=5812

Some braided brake lines...with matching yellow PVC outer

Some new tyres...but only once the shinkos wear out..they're doing ok for now...and get some shiny new valves...hopefully like this
http://www.cycletreads.co.nz/content/catalogueViewEntry.aspx?profilePK=all&entryPK=2337

Then some clipons, gel grips, and some way of attaching the mirrors

Then a digital speedo unit

And lastly replace the single front bulb with a dual bulb setup.

Whether I get any of this done before I think about upgrading is another question.

nudedaytona

19th December 2007, 21:38

and tops out at??? all of 210?? :zzzz:

It finishes way too soon, like me. But truth be told, my balls top out well before then :woohoo: Its too exiting. But If I was to mod I wouldn't say no to a RG500 engine! :devil2:

I'm just glad I didn't get one of those naked bikes commuters - too boring.

Bullitt

19th December 2007, 21:39

Whether I get any of this done before I think about upgrading is another question.

Thats well worth thinking about. I dont know how long till you can get your full but there dont seem much point sinking thousands of dollars into a bike when it dont increase its value at all and you plan on selling it in the short/medium future anyway

Weaver

19th December 2007, 21:55

Mod 0: New tyres. After a 160kph double blow out (it's ok, i threw myself into the road and caught the bike with my crotch) :P I replaced the shitkos with some GT501 Radials. Great tyre. DONE!

There is nothing wrong with the shinkos. I have done over 10000k's on mine and havn't had any problems. I think in alot of occasions people like to blame the tyres instead of their riding abilities.

Also the Shinkos are rated to 210k's which, even with all those go-fast parts it'll have trouble reaching

EnzoYug

20th December 2007, 00:07

Iain

20th December 2007, 09:45

damn you... Ill have to keep up... I will order my screamin demon tomorrow but expect to have to wait till after Xmas before it arrives... I really just want the tank protector that comes with it cause the one I have looks like crap! :P

Aa7

20th December 2007, 12:17

160kph? Easy.

First I'm light, low sixties kg wise, second - I had a good straight to blat on, third - the bikes faired, third - It didn't really have a double blowout, just a nasty puncture and skid but kept her up.

And assuming the speedo is 10kph out at 150 - I could still get mine up to 170-180 with the right conditions, exhaust and airfilter etc...

strap a GPS onto your tank and bring yourself back down to earth dude. the standard hyobags wouldn't put out that much power even at your light body mass/weight and with the speedo misreadings taken into account you would struggle to pull that off without engine mods. the list of mods you want to do will make ytour bike certainly a little different than the standard hyo though :niceone:

Weaver

20th December 2007, 12:18

What does the tank protector that comes with it look like. Has it got a picture of a demon screaming by chance?

Deano

20th December 2007, 12:24

There is nothing wrong with the shinkos. I have done over 10000k's on mine and havn't had any problems.

No ? Didn't they let go round a corner, or were you braking at the same time ?

Weaver

20th December 2007, 12:36

I know I wasn't on the brake mid corner. Alright I admit that incident is one that might not have happened if I have good quality tyres.
I'm not saying they are the greatest tyre ever but they arn't as shit as alot of people say they are. However when the time comes for new ones, I wont be buying Shinkos

Pancakes

20th December 2007, 15:02

...................................Fourth: Bling her out. New high-wattage head lights,....................

I have done a new light loom and bulb on mine and it's way better. Yours will be two H7's (?) not one H4 like mine but I can do a loom for you if you'd like. See below for a pic of one I just finished for another KB'er.

Just one question, how on earth do you get your bike up to 160 km/h ?
I can't get more than 130 km/h out of mine (naked, full throttle, chest on the tank in top gear). Is my bike rooted or am I too fat (75kg) ?

Cos the GT-R reads 10-12% fast and the naked only reads 4% fast. Cheaper than making two different motors and drive trains eh!

haven't read the whole thread but will soon, looks interesting. Lots of Hyo's around now. Confidence and holding your line smoothly will help those Shinko's along too! I don't think they are so bad that you need to get rid of them before you have some K's outta them. Mine go ok leaned over thats for sure!

Gubb

20th December 2007, 21:02

...Seems like I started a trend with that Exhaust.

WarlockNZ

20th December 2007, 21:12

Faaark, mine does 140 in 3rd or 4th without really trying, and I haven't even hit the powerband yet

dude ... had mine up to 176 on the clock and i'm 80Kg

EnzoYug

20th December 2007, 23:48

strap a GPS onto your tank and bring yourself back down to earth dude. the standard hyobags wouldn't put out that much power even at your light body mass/weight and with the speedo misreadings taken into account you would struggle to pull that off without engine mods. the list of mods you want to do will make ytour bike certainly a little different than the standard hyo though :niceone:

Hey man, dont piss on my dream! Besides I'm gonna NOS it... :P

But seriously I've had the bog-standard Hyo 250(R) up to 163. That's on the shithouse speedo tho, so worst case scenario (10% out) I was only doing 146kph. And that's flat with no wind.

Tail wind, down hill (big hill mind you) with un-retarded CDI, new air filter/box, straight-flow exhaust etc... I reckon she'd do 160-165(ish) for real.

EnzoYug

20th December 2007, 23:55

I'm not saying they are the greatest tyre ever but they arn't as shit as alot of people say they are. However when the time comes for new ones, I wont be buying Shinkos

The first thing I did was loose the Shinkos. 4000k service - bang! off they come. GT501 Radials, never looked back.

Amazing tyre, it'll hold everything plus more than my 250 can give it. Save up, buy the tyre. You'll live faster, be safer and feel more confidant.

EnzoYug

20th December 2007, 23:56

What does the tank protector that comes with it look like. Has it got a picture of a demon screaming by chance?

I forget. I gave mine to a friend, but I'll ask him for a photo. He was quite stoked with it.

325rocket

20th December 2007, 23:58

Tail wind, down hill (big hill mind you) with un-retarded CDI, new air filter/box, straight-flow exhaust etc... I reckon she'd do 160-165(ish) for real.

but with no more to get you out of the shit if you need it... if you want more speed why not get a faster bike?

EnzoYug

21st December 2007, 00:05

but with no more to get you out of the shit if you need it... if you want more speed why not get a faster bike?

I don't want to go faster. Well, actually that seems to contradict everything I've said so far. What I mean is that I don't want to go faster than 150 - not on this bike. What I do want is to GET TO 150 asap. I want acceleration, my bike does 90% of it's miles in the city - so top end is not the goal.

Having a great looking 250 the can flick around every thing else when I need it to, and get out of the corners nice and quick when I'm on the corro loop. That's the goal.

Not a power machine with 7 gears and top speed rivalling most light aircraft. That's for next year.

xwhatsit

21st December 2007, 00:19

But seriously I've had the bog-standard Hyo 250(R) up to 163. That's on the shithouse speedo tho, so worst case scenario (10% out) I was only doing 146kph. And that's flat with no wind.

Aren't top-speed 250cc pissing contests fun :lol:

I wouldn't be surprised if it could crack 150kph. My bike -- which has 1 less horsepower than the Hyos -- can supposedly hit a true 145-150kph (haven't tried it myself, don't like treating the engine that way). It's naked, too. Significantly lighter though.

Anyway that's very boring.

That's an ambitious list if you're going to do like most people here and sell their 250. I'm all for 250cc blingage, but I will be keeping my bike. If I only had a year to wait I'd just put up with it stock, which is hardly very bad.

Weaver

21st December 2007, 08:32

Tail wind, down hill (big hill mind you) with un-retarded CDI, new air filter/box, straight-flow exhaust etc... I reckon she'd do 160-165(ish) for real.

I think it should be able to manage a tonne with all the go fast parts, but that'll be pushing it, because no matter how much horsepower you have, the gear ratios are still the same. At 160 plus you'll be very near the redline

EnzoYug

21st December 2007, 15:05

So the GT250R project is rocketing along:

Work completed so far:
Un-Retarded Ignition - DONE! Removed the 'magic wire' from the CDI unit and now my bike no longer passes NZ Emission laws for newly imported vehicles! YAY! And holy shit does she accelerate now, the smoothest power curve since my CBR. FEEL THE POWER OF HYOSUNG!

Straight Flow Exhaust - DONE! Installed my SD Carbon fibre exhaust. Apart from the fact that the bike now rocks straight to the red-line in any gear, the exhaust is very cool looking and very very cool. So cool I went for an hours blat last night and afterwards could put my hand straight onto the carbon fibre - merely warm. No more accidental burns :D

New Indicators / Lights - DONE! New higher wattage headlights and clear (not orange) indicators. Apparently these indicators will be standard on the 2009 bikes.

New Tyres - DONE! GT501 Radials. The best (all rounder) a Hyo can get.

Still in the works....
I've just ordered a STEBEL Magnum horn, HEL Steel Braided brake lines, BMC air filter, DP Scintered brake pads and Pazzo race levers. When I take her in to the shop I'll get her re-jetted to suit the new setup.

On that note - Anyone know a better workshop for HYOSUNGS than Red Barron? I'm leaning towards JFK... any ideas?

98tls

21st December 2007, 15:33

:Punk:Sounds like your having fun.modding is good,enjoy.

325rocket

21st December 2007, 18:18

98tls

21st December 2007, 18:27

hey man whats this mod? how do you do it? TRE as in timing retard eliminator,or do as he has done.

chazza404

21st December 2007, 18:50

Nice list ya got there, just wondering what kind of price all that is gonna cost ya? itll be really cool when its done, looking forward to it

Pancakes

21st December 2007, 21:15

hey man whats this mod? how do you do it?

Go here (http://www.korider.com/forum/modules.php?name=Forums&file=viewtopic&t=376) and see if you can make sense of it then try it out in a way you can easily repair if your guess was wrong. I haven't done it on mine yet cos it seems they wired the bikes with spare parts from uncle bob's rainbow wire shop and all the looms are a combination of colours etc. There are some pic's there of the "black box" plugs but I haven't had a look at mine to see how it all lines up.

Lots of the posts say pull the wire out. I would cut it so you can use a crimp connector or solder it back together if you've got it wrong.

Pancakes

22nd December 2007, 12:38

Taz

22nd December 2007, 12:50

and tops out at??? all of 210?? :zzzz:

Faster than my 1100....... :(

EnzoYug

22nd December 2007, 14:48

Looked under my CDI just now and it seems the dealer has sorted the ignition retard wire for me. The pics are the wires showing which one is cut, the code on the top of the unit and the code on the end of the unit if that means anything to anyone.

That's exactly what I did - only a little neater. Didn't actually 'Cut" the wire, just removed it from the plug and insulated it. If anyone wants to do this but is worried about getting the wrong wire try this:

Hyosung GT250/R 2006/7 (NZ new imports)
1. Open up the seat.
2. Un bolt the CDI unit. (small black brick next to the relays)
3. Disconnect the Brown plug from the CDI. BE GENTLE.
4. Get a very small Alan key - preferably one that will fit into on of the circular holes in the 'male' end of the brown plug.
5. Locate the Green/Blue wire.
6. This wire should be in the same position as in Pancakes photo - if it is in a different position DO NOT REMOVE.
7. Use the alan key to carefuly push the copper contact out of the plug. It should pop out the other side with the wire, blue plastic bung, and copper contact all in perfect condition.
8. Tape up the end of end of the copper contact VERY thoughly with electrical tape. If you have some kind of plastic insulation to cover it as well I suggest using that.
9. Tuck the loose wire back into the loom.
10. Reattach the CDI.
11. Power up the bike but DONT start it. Check all your lights work, and check the digital dash if you have one.
12. If everything works fine continue - if anything has stop working then stop here - you've fucked up.
13. Fire up the bike. Let it idle. Listen for anything odd - firing on one cylinder etc... normal? Good!
14. Test the kill switch. If it doesn't work, you fucked up.
15. Everything works go ride the bike. You should notice a VERY smooth power curve now.

Extra for experts: Go buy a nice big exhaust, or get yours debaffled. Then get a new air filter, then get it re-jetted. (being cheap and not getting the re-jetting will fuck your bike in the long run) Enjoy the most powerful Hyobag on the block.

HornetBoy

22nd December 2007, 18:45

Bloody hell thats going to be a quick hyo ,nice modding mate :niceone: love the new exhaust ,how much has that cost you so far ?

Weaver

23rd December 2007, 15:08

I know this is really the wrong thread for this, but all the arguments have been happening in this one.
Today, with my arse slid right back in the seat, stomach & chest flat on the tank and my head as low as safely possible I had my standard GT250R up to 169kms(keep in mind the speedo, like all GT250R's, is out). It would'nt go any higher though. I was to busy watching the road and speedo to look at the tacho, but I imagine it was on the redline and this is what would have been limiting my speed.
So in short, the GT250R's gear ratios wont allow these great speeds people always seem to talk about

Sucks eh

FilthyLuka

23rd December 2007, 16:49

being cheap and not getting the re-jetting will fuck your bike in the long run

You would need to be doing something real wrong for it to fuck it up catastrophically, will probably just run a bit dodgy.

Now that you've done the easy stuff, you can:

1) Port and Polish, all you need is some carbide bits, a marker pen, some gaskets, some time, a micrometer, a telescopic lever thingie that pops out and measures inside diammeters (cant remember what it is called), some more time, a scriber... okay you need alot of shit, but thats not the point!
2) skim the head, find out the distance between valves and piston when they are closest together, skim head appropriately. Or skim even more and mill the piston...
3) Mirror polishing, lots and lots and lots and lots and lots of sanding...
4) high compression pistons... you know you wanna
5) 50/50 mix of 101 race fuel and 98

acceleration and all...

I've done 2 of the above (port and polish, mirror polishing), cleaned out the engine, debaffled the exhaust, put a velocity stack on the carb, jetted the carb appropriately, added some fancy HT leads and a big arse fuck coil too. added tooth on front sprocket. I've seen 150km/h according to Mr. GPS and got there pretty quick. Round town is perfect, sits at about 5500rpm at 100km/h. Dyno run said 36hp at the wheel.

Did i mention this was on a gn250?

All fun and games eh :D

But seriously, who cares about top speed? i mean, 150, sure, woohoo, zx10 does 280 without caring...

Have fun with your bike, don't blow it up now ;)

Denis

HungusMaximist

23rd December 2007, 16:57

Well, big ups Enzo for having a mod frenzy....!

I'd be quite interested in seeing how your bike turns out aye so keep an eye out for the Auckland Uni SMC club rides or Wednesday/Monday Night Mentor Ride, I'll be there.

My 929 is still faster though.. !

325rocket

23rd December 2007, 17:26

Go here (http://www.korider.com/forum/modules.php?name=Forums&file=viewtopic&t=376) and see if you can make sense of it then try it out in a way you can easily repair if your guess was wrong. I haven't done it on mine yet cos it seems they wired the bikes with spare parts from uncle bob's rainbow wire shop and all the looms are a combination of colours etc. There are some pic's there of the "black box" plugs but I haven't had a look at mine to see how it all lines up.

DONE !!! its about a 2 minute job and has sorted all my "unpredictable" cornering issues. before i had to feather the throttle to get back on the gas now its smooth as...

Pancakes

23rd December 2007, 17:51

..........................So in short, the GT250R's gear ratios wont allow these great speeds people always seem to talk about

Sucks eh

Thats the first thing I though when I read the AMAZING speeds people were posting on stock Hyo 250's. Thats a few grand over redline and a loooong road with the top speed trade off with accelleration.

You would need to be doing something real wrong for it to fuck it up catastrophically, will probably just run a bit dodgy...........................................

Running lean and overheating the exhaust valve stem coupled valve bounce when they are over-revved with soft valve springs (and they must be looking at the torque curve on these, they are made for low efficiency not top end) will see the valve head in the combustion chamber in the near future. Haven't heard of it on a Hyo but thats how you mod and kill a bike.

Sounds like the bizzo GN FilthyL, way ta go!

FilthyLuka

23rd December 2007, 17:57

Running lean and overheating the exhaust valve stem coupled valve bounce when they are over-revved with soft valve springs (and they must be looking at the torque curve on these, they are made for low efficiency not top end) will see the valve head in the combustion chamber in the near future. Haven't heard of it on a Hyo but thats how you mod and kill a bike.

Sounds like the bizzo GN FilthyL, way ta go!

Cheers :)

I know bout the running lean will cause all sorts of nasties, but surely that extent of lean-ness (is that the term im lookin for? something like that) wont be caused by a replacement air filter and a free flow pipe?

Oh, and dude who started this thread whose name i can't remember because the back button is all the way up there, i know a guy out in henderson called warren bridges, the guy is a master with carbs, PM me if you want his number. He doesn't charge an arm and a leg either

Pancakes

23rd December 2007, 18:16

Cheers :)

No worries, sounds like you've done enough work to deserve a "nice one"!

I know bout the running lean will cause all sorts of nasties, but surely that extent of lean-ness (is that the term im lookin for? something like that) wont be caused by a replacement air filter and a free flow pipe?

I wouldn't say that it WILL happen but with the power difference you can get from those mods to a Hyosung and that it is still a small bike so sitting on redline at WOT is still very likely I think there would be a really good chance the heat stress would get that high.

Oh, and dude who started this thread whose name i can't remember because the back button is all the way up there, i know a guy out in henderson called warren bridges, the guy is a master with carbs, PM me if you want his number. He doesn't charge an arm and a leg either

PM sent also, I need to get the carbs done in mine so I can start using the straight pipe.

Weaver

23rd December 2007, 20:49

has sorted all my "unpredictable" cornering issues

Did that take out that flat ocassional flat spot around 6000rpm?

EnzoYug

24th December 2007, 00:32

acceleration and all...

I've done 2 of the above (port and polish, mirror polishing), cleaned out the engine, debaffled the exhaust, put a velocity stack on the carb, jetted the carb appropriately, added some fancy HT leads and a big arse fuck coil too. added tooth on front sprocket. I've seen 150km/h according to Mr. GPS and got there pretty quick. Round town is perfect, sits at about 5500rpm at 100km/h. Dyno run said 36hp at the wheel.

Did i mention this was on a gn250?

Wow. Nice going. I was going to wait till the basics are done till I start fucking with the engine. Did you do port/polish yourself? How 'involved' did it get? I'd be quite keen to give mine a go once the basics are done and a bit of guidance would be fricken awesome!

EnzoYug

24th December 2007, 00:36

DONE !!! its about a 2 minute job and has sorted all my "unpredictable" cornering issues. before i had to feather the throttle to get back on the gas now its smooth as...

Great to hear! More power to the hyo I say!

disenfranchised

24th December 2007, 07:57

I've seen 150km/h according to Mr. GPS and got there pretty quick. Round town is perfect, sits at about 5500rpm at 100km/h. Dyno run said 36hp at the wheel.

Did i mention this was on a gn250?

I think I may have seen you round.
A few months back I was at some lights next to a guy on a GN, and he absolutely smoked me when we took off.

Surprised the hell outa me!! :gob:

I always suspected it wasn't standard...either that or it was a GN400

FilthyLuka

24th December 2007, 08:03

I think I may have seen you round.
A few months back I was at some lights next to a guy on a GN, and he absolutely smoked me when we took off.

Surprised the hell outa me!! :gob:

I always suspected it wasn't standard...either that or it was a GN400

i live out your end of the woods so may very well have been me :yes:

Wow. Nice going. I was going to wait till the basics are done till I start fucking with the engine. Did you do port/polish yourself? How 'involved' did it get? I'd be quite keen to give mine a go once the basics are done and a bit of guidance would be fricken awesome!

Yeah, i did the port and polish myself. Took awhile to get everything the same though. Pretty much just slap the gasket on, outline the metal between the port and inner ring of the gasket, then take of some of that. The hardest bit is getting them the same, but a expansiony T looking thingie and a micrometer will do the trick for that. Oh, that and forking out for carbide bits...

Its pretty simple, you just gotta be make sure the ports are the same. Hell, im sure you would see an increase in power if your just wipped the head off and sanded out all the little burrs and bumps from the ports!

Weaver

24th December 2007, 08:46

a expansiony T looking thingie

Its called a telescopic gauge :cool:

FilthyLuka

24th December 2007, 08:48

Its called a telescopic gauge :cool:

Thats the one! bling for you my friend

Bonez

24th December 2007, 09:12

Tis nice to see such an enthusiastic thread. Keep it up chaps.

Fub@r

24th December 2007, 10:11

Eight: Tail hugger & Tail tidy unit. Rip off the shovel on the back of the bike and enjoy all the road shit leaving a stripe up my back. Then get a tail hugger installed along with chain guard to match - for ideas see Warlock's GT250R.

http://www.korider.com/forum/modules.php?name=Forums&file=viewtopic&t=5812

No cost tail tidy for you :)

Pancakes

24th December 2007, 10:30

Wow. Nice going. I was going to wait till the basics are done till I start fucking with the engine. Did you do port/polish yourself? How 'involved' did it get? I'd be quite keen to give mine a go once the basics are done and a bit of guidance would be fricken awesome!

It can look the same but a "polish" and a "port" are different things. Polish your own stuff by all means. Remove dags and casting marks. Match up the manifolds to the heads etc and generally shine it up. Basicly factory but in a tidy way they don't bother doing because of mass production.

Porting is more sculpting the intake and outlets to give different flow characteristics and can be better or worse for your performance. This is where knoledge of fluid dynamics, years of experience and a flow bench are real handy. Bigger isn't always better and with porting your not just tidying up but reshaping the unit. I have seen some race car heads where the tuner actually fills in some areas a wee bit and polishes that so it's a completly different shape from the factory one. Especially when tubroing a non-turbo head etc.

Like any mods, one thing at a time, a little bit at a time and try try again. Have fun!

FilthyLuka

24th December 2007, 10:38

It can look the same but a "polish" and a "port" are different things. Polish your own stuff by all means. Remove dags and casting marks. Match up the manifolds to the heads etc and generally shine it up. Basicly factory but in a tidy way they don't bother doing because of mass production.

Porting is more sculpting the intake and outlets to give different flow characteristics and can be better or worse for your performance. This is where knoledge of fluid dynamics, years of experience and a flow bench are real handy. Bigger isn't always better and with porting your not just tidying up but reshaping the unit. I have seen some race car heads where the tuner actually fills in some areas a wee bit and polishes that so it's a completly different shape from the factory one. Especially when tubroing a non-turbo head etc.

Like any mods, one thing at a time, a little bit at a time and try try again. Have fun!

i agree with Mr pancakes, if you dont have some serious tools and know how at your disposal, doing just a polish is the best bet.

325rocket

24th December 2007, 10:56

Did that take out that flat ocassional flat spot around 6000rpm?

100%.
the connector you remove from the connecting block isnt like the normal ones that lock them self in so you only have to push it out. its held in by a rubber grommet type thing so just push it out dont cut it.

Weaver

24th December 2007, 16:54

I have just removed the wire and taken the bike for a test ride, and the power was sooo smooth. Very lurvely

Fub@r

24th December 2007, 19:01

Weaver

24th December 2007, 19:11

If you skim the head (assuming the combustion chamber is in the head and not the piston) it will raise the compression. It is not a simple job becasue you can easily take to much taken off or not enough. Regardless, once it has been skimed, you will need to get it rejetted straight away. This is the same with the air filter.
If you put a high flow air-filter on then you will get more air in the mixture. This will cause the bike to run lean which can cause detonations, which results in the pistons melting.
Nothing wrong with polishing the head. Just make it so thats a smooth flow, but don't actually polish it. It needs a semi rough finish to help mix the fuel and oxygen.

Personally i'm not going to bother doing any of this to my GT250R. But good luck to anyone that gives it a try :niceone:

FilthyLuka

24th December 2007, 22:29

My problem is my accountant (aka wife) wont let me upgrade at this time. Have a mortgage to pay. Although did find a nice SV650s :)

Anyway, I have semi debaffled and was thinking over Xmas I might do the polishing.

Whats the cost to do a skim? And mod the air filter?

Once these are done, I then get the carbs rejetted?

Oh mate, i wouldn't skim the head, i mean, lots of effort, easy to fuck up and if you run lean for to long, shit starts to melt.

You can have either performance or reliability

Seriously, the most you would want to do is a polish, free flow pipe, pod filter/airbox mod, carb jet

Get the sand paper out and work out all the burs and roughness in the ports

Then give the bike to warren with the standard air box, hand him the pod and say "jet it for this." That way, when you get the bike back, it will go like stink and not melt anything.

Dont do major work, i mean, seriously, your just gonna get a big bike in the next two years anyway

FilthyLuka

24th December 2007, 22:31

Nothing wrong with polishing the head. Just make it so thats a smooth flow, but don't actually polish it. It needs a semi rough finish to help mix the fuel and oxygen.

um, what? The carb mixes the fuel and the oxygen. The reason you polish the ports is to aid flow into the combustion chamber. The flow is increased as there is less friction between the fuel/air particles and the port surface.

It stops shit sticking pretty much, nothing more annoying than sticky shit

Fub@r

24th December 2007, 23:10

your just gonna get a big bike in the next two years anyway

I need your accountant :yes:

Rejet and polishing sounds like me

FilthyLuka

24th December 2007, 23:20

Rejet and polishing sounds like me

Good man! Will be willing to give you a hand with that polish, still have a few sheets of unused sand paper of varying grades around here somewhere... PM me if you wanna get it done in january some time...

You would be suprised at how rough engines come outta the factory. All bumpy and not shiny and stuff, ah you'll see.

Oh, and merry fucken christmas you hyosung riding mod monkey!

BAH HUMBUG!

Denis

EnzoYug

24th December 2007, 23:30

Good man! Will be willing to give you a hand with that polish, still have a few sheets of unused sand paper of varying grades around here somewhere... PM me if you wanna get it done in january some time...

Heya, I'm quite keen to get mine polished as well. Perhaps we could make an event of it?

After all there's nothing like having someone stand behind you and say "umm... I'm pretty sure you've mounted that backwards..." to make you glad you didn't try it all on your lonesome.

FilthyLuka

24th December 2007, 23:48

Heya, I'm quite keen to get mine polished as well. Perhaps we could make an event of it?

After all there's nothing like having someone stand behind you and say "umm... I'm pretty sure you've mounted that backwards..." to make you glad you didn't try it all on your lonesome.

haha, yeah that happens. I got real pissed off at my new battery for blowing fuses all the time... turned out the leads were the wrong way around, god fucking damnit...

But yeah, i dont have much experience with hyosung gt series but two extra hands/eyes never hurt!

Ill be keen, sort it out, go on, do it.

FilthyLuka

25th December 2007, 01:37

I need your accountant :yes:

single mate, no accountant for me! #sigh#

Weaver

25th December 2007, 06:54

um, what? The carb mixes the fuel and the oxygen. The reason you polish the ports is to aid flow into the combustion chamber. The flow is increased as there is less friction between the fuel/air particles and the port surface.

It stops shit sticking pretty much, nothing more annoying than sticky shit

Tis what I was told by the engine reconditioner that built a 1600 X-flow motor up for me. He said that the carb doesn't completely mix the fuel and that a highly polished intake (so smooth and shiny that its almost chrome like) doesn't assist the mixing process.
But hey, what ever floats your boat.

Time to open some christmas presents (hopefully all bike related)

AllanB

25th December 2007, 07:19

Personally I'd flag the pod filter (filer directly attached to the carb). These were absolutely fine in the 80's when an airbox was just something the factory stuffed on the end of a carb between the frame rails. On any modern bike the airbox now gets a lot more attention re size inlet etc. A free flow filter for the stock box, pipe and carb settings will do the trick IF preformed by someone who knows what they are doing.

Without sounding like a arse - the GTR250 is a nice bike, however its never going to set the performance world on fire, and at the end of the day, well its a 250. As you will no doubt get a larger ride in the future (6 months of begging at least) I'd leave the engine alone apart from a pipe if you are after a bit more noise (and lets all face it if it sounds louder it feels faster) and concentrate on personalising other aspects.

Why - for no other reason than resale value - if you've fucked with the engine a lot a shop will not be very interested in trading, ditto private buyers. Bling can be easily removed and stock bits returned if so desired (sell bling on Trademe or add to the next bike).

Thats what I do - each stock part thats replaced is popped in a box 'just in case'. I sold a bike I'd had from new for 23 years a couple of years ago - the box of parts that went with that was bloody heavy!

325rocket

25th December 2007, 08:55

Tis what I was told by the engine reconditioner that built a 1600 X-flow motor up for me. He said that the carb doesn't completely mix the fuel and that a highly polished intake (so smooth and shiny that its almost chrome like) doesn't assist the mixing process.
But hey, what ever floats your boat.

and he was right. you want inlets smooth not polished. keep to 80 grit or less. exhaust ports can be polished.

good luck

Pancakes

25th December 2007, 21:04

Oh mate, i wouldn't skim the head, i mean, lots of effort, easy to fuck up and if you run lean for to long, shit starts to melt.

You can have either performance or reliability

Seriously, the most you would want to do is a polish, free flow pipe, pod filter/airbox mod, carb jet

Get the sand paper out and work out all the burs and roughness in the ports

Then give the bike to warren with the standard air box, hand him the pod and say "jet it for this." That way, when you get the bike back, it will go like stink and not melt anything.

Dont do major work, i mean, seriously, your just gonna get a big bike in the next two years anyway

Thats some good advice.

Tis what I was told by the engine reconditioner that built a 1600 X-flow motor up for me. He said that the carb doesn't completely mix the fuel and that a highly polished intake (so smooth and shiny that its almost chrome like) doesn't assist the mixing process.
But hey, what ever floats your boat.

Time to open some christmas presents (hopefully all bike related)

And he was right. FL has covered that back up the thread a ways.

and he was right. you want inlets smooth not polished. keep to 80 grit or less. exhaust ports can be polished.

good luck

Yep. Once you get them open you'll see there's lots to tidy up, tags & dags, before you get close to a mirror finish. I belive we are using "polish" in the head work sense not meaning that it it a polished finish. Different things.

Weaver

26th December 2007, 05:29

Thats what I was saying initially Pancakes. That it needs a semi-rough finish and an actually polished finish

FilthyLuka

26th December 2007, 08:32

Yep. Once you get them open you'll see there's lots to tidy up, tags & dags, before you get close to a mirror finish. I belive we are using "polish" in the head work sense not meaning that it it a polished finish. Different things.

Ah, sorry weaver, yes you are right, you dont want a mirror finish. I thought you meant don't even go over it with a sanding roll and leave it after a grind out with a carbide bit...

Anyway, on a similar note. There is a guy in the USA (ill see if i can find a link and post it up) that actually found a way to tap (read thread) the ports. The idea is, that when a droplet of un-vaporised fuel hits the thread in the port wall, it splatters off into lots of small drops that easily vaporise... To bad im not a good enough metal worker or i would try this... Would be nice to see a dyno read out for it and see if there is actually any improvement

sprag

26th December 2007, 18:16

That's exactly what I did - only a little neater. Didn't actually 'Cut" the wire, just removed it from the plug and insulated it. If anyone wants to do this but is worried about getting the wrong wire try this:

Hyosung GT250/R 2006/7 (NZ new imports)
1. Open up the seat.
2. Un bolt the CDI unit. (small black brick next to the relays)
3. Disconnect the Brown plug from the CDI. BE GENTLE.
4. Get a very small Alan key - preferably one that will fit into on of the circular holes in the 'male' end of the brown plug.
5. Locate the Green/Blue wire.
6. This wire should be in the same position as in Pancakes photo - if it is in a different position DO NOT REMOVE.
7. Use the alan key to carefuly push the copper contact out of the plug. It should pop out the other side with the wire, blue plastic bung, and copper contact all in perfect condition.
8. Tape up the end of end of the copper contact VERY thoughly with electrical tape. If you have some kind of plastic insulation to cover it as well I suggest using that.
9. Tuck the loose wire back into the loom.
10. Reattach the CDI.
11. Power up the bike but DONT start it. Check all your lights work, and check the digital dash if you have one.
12. If everything works fine continue - if anything has stop working then stop here - you've fucked up.
13. Fire up the bike. Let it idle. Listen for anything odd - firing on one cylinder etc... normal? Good!
14. Test the kill switch. If it doesn't work, you fucked up.
15. Everything works go ride the bike. You should notice a VERY smooth power curve now.

Extra for experts: Go buy a nice big exhaust, or get yours debaffled. Then get a new air filter, then get it re-jetted. (being cheap and not getting the re-jetting will fuck your bike in the long run) Enjoy the most powerful Hyobag on the block.

Just have to say big ups to you, just did it to my bike and man what a difference it has made, no more flat spots and take off is alot faster and better :)

Cheers EnzoYug :)

Oh and bling on its way

EnzoYug

27th December 2007, 12:11

Just have to say big ups to you, just did it to my bike and man what a difference it has made, no more flat spots and take off is alot faster and better :)

Cheers EnzoYug :)

Oh and bling on its way

No problem. Enjoy the POWER of Hyosung!

325rocket

27th December 2007, 13:03

No problem. Enjoy the POWER of Hyosung!

is that an oxymoron :bleh:

Fub@r

27th December 2007, 17:30

Had some free time this afternoon so did some tinkering on my Mango.

Have pulled the blue/green wire from the CDI unit, and the engine and everything still works will give it a test ride tomorrow as I had a few beers whilst doing the mods.

I also did the tail tidy mod that was linked to at Korider. Everything works great just as the guy said but there is a really big BUT!

The Korider thread is a guy from aussie and their numbers plate are quite a bit smaller than ours so the plate will not mount between the indicators due to its width.

So used the stereo tin strip and cut it in half and hung the two halves down from the stop light mounting points and attached the number plate to that.

Overall the mod didn't take too long, definetly took longer than 20 minutes as the Korider guy quoted, but I wanted to do it nicely. Will post a pic later on.

sprag

27th December 2007, 19:08

Fub@r

27th December 2007, 20:15

Sweet would like to see that :)

http://img.photobucket.com/albums/v490/Fubar_nz/rear.jpg

http://img.photobucket.com/albums/v490/Fubar_nz/side.jpg

Fub@r

28th December 2007, 16:49

I've since found this idea at Korider. Will have a crack at making this bracket over the weekend, that will solve the issue of the lack of space between the indicators to enable me to get the number plate higher

http://img.photobucket.com/albums/v490/Fubar_nz/bracket.jpg

Gubb

28th December 2007, 17:01

That's my bike you hungus.

I bought the bracket for $20ish from TSS in Welly. Called something like "Arsend".

Fub@r

28th December 2007, 17:42

I bought the bracket for $20ish from TSS in Welly. Called something like "Arsend".

$20 eh will have to have a hunt around the Auckland bike shops :)

Gubb

28th December 2007, 19:44

Piece of piss to install if you have the right tools (a-la 325rocket).

Got two sliding brackets that bolt into place to fit any sized plate.

http://www.kiwibiker.co.nz/forums/customprofilepics/profilepic13310_3.gif

Shows it after the work, needing a clean.

That's Weaver's bike beside it, before he got molested by a massive seagull. True story.

sprag

28th December 2007, 19:51

Weaver

28th December 2007, 20:21

That's Weaver's bike beside it, before he got molested by a massive seagull. True story.

Fucken the size of an albatros it was, honest. Swooped down onto my back while I was riding along at the speed limit, and it started attacking me in an extremely deadly/dangerous manner.

Still have nightmares about that

Fub@r

28th December 2007, 20:44

Might have crack at making two U shaped packers to move the indicators out so I can move the plate upwards.

Got time up my sleeve, plus its a bit more satisfying when you have made the stuff :)

Vetran

29th December 2007, 23:20

Anyone got a rear seat cowl on? if yes where did you get it from?

Gubb

30th December 2007, 09:22

Try here. (https://www.ngales.com/products_info.asp?id=91&type=accessories&cat=21&sub=11&rge=&kw=&man=)

Donut

2nd January 2008, 21:34

i have just removed the greem/blue wire from my cdi, there seems to be no flat spot and the bike is running fine..... except now where the falt spot was... my tacho now goes nuts as soon at it gets to about 5000rpm it starts "floating" between 5000-6500 and comes right once it gets to about 7000.... has anyone else found this problem ?

Iain

4th January 2008, 07:30

I have removed the ignition wire but havent noticed anything strange with the tach. I have noticed it is much smoother changing gears, both up and down. I had high expectations after reading what others had written and I didnt feel disappointed so something good happened :)

I noticed the flat spot alot, particularly in 3rd, it would start at 5000rpm and would return to normal as soon as it hit 6000rpm (perhaps I shouldnt be at 5000rpm in 3rd :) ).

I will keep an eye on my Tach in case I have just not seen what you describe.

Fub@r

4th January 2008, 18:07

Well my rangi-rear end tail tidy had a small setback on the Coro Loop.........lost a bolt on the number plate :)

Ended up removing my rego and used the bolt from that to secure my number plate again

As for the CDI unit, on the Coro Loop I noticed that as has been said above the gear changing was a hell of alot more smoother and no more flat spot issues. Had no problems with my tach after doing it

Donut

4th January 2008, 19:37

lol, maybe my tach is just fubar :P.... and im sure your tail tidy wasnt half as rangi as mine... it was done on new years when i was drunk with a wood saw .. XD

Iain

11th January 2008, 09:46

Maybe reconnect the wire and see what happens to the tach?

Donut

13th January 2008, 10:07

yeah i reconected it and it did the same for about 3 days thn it come right, so i decided fudge it ill cut it and who cares about the tacho and now its running sweet no problems at all :D just some weird luck i guess

rphenix

13th January 2008, 18:05

I hope nobody is actually cutting the wire, you can just remove the plug, then with some tweezers push the metal tab that holds the connector into the plug :) heat shrink pipe to isolate the connector and done.

Ive done it that way both to my GV, and to the wifes GT no problems on either model.

Donut

13th January 2008, 20:03

Dodger

14th January 2008, 12:18

then with some tweezers push the metal tab that holds the connector into the plug :)

Well I spent around 10 minutes looking for some tweezers/pliers when I did mine, and then gave up and cut the wire :Punk:

Donut

14th January 2008, 20:51

Well I spent around 10 minutes looking for some tweezers/pliers when I did mine, and then gave up and cut the wire :Punk:

Lol sweet im not the only one... no biggie, its not like im actually want to conect it again :laugh:

:Edit:Man im either asian or really drunk when i post on here.... who can guess which :beer:

Dodger

15th January 2008, 08:37

Latest "mod"

Yuasa YTX14-BS Battery, as my stock one has died and wouldn't hold a charge (1.5 years, 17000k's) :angry:

Donut

15th January 2008, 16:37

Fitted some "neon" lights under the read and in the front cowl on mine looks pretty funny at night time :P

Filter_nz

18th January 2008, 08:54

This is my second reply on the KB forums.
Thought I'll list the mods as see what outher think.

I've got the 2007 GT250R -Red with black frame

Mods this far:

1) Progrip tank pad (not really a mid)
2) Removed the retard wire from CDI
3) Screaming Demon Stainless exhaust
The guy who makes these on OZ custom made mine WITHOUT the Screaming Demon logo plate riveted to the pipe.

4) Carbie jet kit - YET TO ARRIVE FROM USA
(includes needle shim, primary and main jets, throttle slide, air filter and modifactions for air box)

Will let you know how the bike runs with the jetkit.

My thoughts on the mods:

SCREAMING DEMON EXHAUST
In my opinion, after installing the straight through exhaust the bike ran slightly slower below 6-7k rpm and above 7k a little better, overall don't expect much from an exhaust mod except a nicer sound.
The bike runs a little lean, you can tell from listing to it run when it's hot... and over the last 1000kms the burble when backing off the gas is getting more noticeable.

REMOVING THE RETARD WIRE IN CDI
To be fair, this made almost no difference. I double checked to make sure it was the correct wire. Yes the power curve is smoother, and the flat spot is gone but in all honesty this mod is over-rated.

JET KIT
Hadn't planned on buying this however the bike is starting to burble when backing off the gas after the free-flow exhaust was fitted -hasn't started 'popping' yet.
TSS Motorcycles said there is no need to rejet, they'll just raise the needle or do a carbie swap. I wasn't happy with what they were suggesting or the price is was going to cost just to raise the needle so ordered the whole jetkit from the states and will fit it myself. -Hopefully this will make a noticeable increase in the performance.

Dodger

18th January 2008, 15:37

Fitted some "neon" lights under the read and in the front cowl on mine looks pretty funny at night time :P

Photo?

I have some red "neons" under mu 50cc scooter to piss off the boy racers :)

bell

18th January 2008, 21:26

This thread is all about my sexy GT250R, or at least it will be - I'm starting to customise it now that I've hit 8,000k without the slightest problem. So here's a list of what I've done so far and what needs doing. I'll update as I go.

While this magazine is not always the most exciting reading you may find an article in the JAN/FEB "Australian Road Rider" magazine worth a look (Red Guzzi Norge on the cover).

Project "Nightfighter - it's a 650 Comet that they've done a heap of mods on. It might give you a few ideas?

Gubb

20th January 2008, 17:03

JET KIT
Hadn't planned on buying this however the bike is starting to burble when backing off the gas after the free-flow exhaust was fitted -hasn't started 'popping' yet.
TSS Motorcycles said there is no need to rejet, they'll just raise the needle or do a carbie swap. I wasn't happy with what they were suggesting or the price is was going to cost just to raise the needle so ordered the whole jetkit from the states and will fit it myself. -Hopefully this will make a noticeable increase in the performance.
Honestly, i'd only re-jet if you alter the air box/filter as well. Then again, how are you going to know if you have the jetting right without perfecting it on a dyno. Sounds like a risky operation by yourself, i'm leaving mine to the pro's with the proper tools.

WarlockNZ

20th January 2008, 17:13

Go to JFK in Manakau .. they do an awesome job.

Here's how it works. and having had it done to my old Hyosung i know what i'm talking about.

If you open the exhaust, the bike will start to run really lean, this is of course where you get more power, the leaner you run the quicker you go until the engine explodes.

In order to compensate for this, you have to increase fuel flo to bring it back to normal, of course if you increase the fuel, you have to also increase the air flo.

Make sense ?? .. good ...

The boys at JFK did my old bike and it made a massive difference, 10HP in fact, and they have tried all sorts of combos on a dyno to get it right.

I'm not going to tell you what the combo is, because JFK deserve the business, i would say, get it done by the pro's, they know what they are doing and it's not that expensive, if you already have the open flow exhaust, it's only about $140 i think.

On a side note, has anyone bought my old Hyo yet ???? hmmmm .. LOL

Oh and i still have an open pipe for a gtr if anyone wants it, not open enough that you have to re-jet, but open enough to sound shit hot :)

Weaver

20th January 2008, 20:40

i'm leaving mine to the pro's with the proper tools.

I'm leaving mine till I sell it and own a 600.
I had looked at doing some of the stuff that people here are talking about. But then again I only intend on having the bike for another year. I'd more rather put that $500 plus towards getting a bigger bike.

But Hubba Gubba is right. If you get your local bike shop to rejet it, it'll run well. But if you get it rejetted on a dyno, then it'll run at its best.

Filter_nz

21st January 2008, 19:46

Gubb

21st January 2008, 20:00

So you bought a jet kit without knowing the specs of it?

Good luck mate, hope you don't get too burnt.

Filter_nz

28th January 2008, 08:25

Ok time to update.. It took me about 4 hours to do but it's done.
On the GT250R..

Had to take the ferrings off and remove the carbs altogether. The instructions say you don't need to remove them but IF you don't you'll strip the screw heads trying to get the carbs apart.

Here is a summary of the upgrade:

1) Upgraded pilot jets

2) Main jets
Front: 92 upgraded to 95
Rear: 95 upgraded to 97.5

3) Jet needles
Stock on position 2 (of a possible 3) Moved to position 3 which increases mid range flow. (actually sits lower the even position 3 with a spaced washer). Lowering the position effectively raises the needle out of the jet

4) Air filter
Modified the stock filter by removing the stupid tiny intake core, intake is now more than double the size

MODS ALREADY DONE

5) CDI retard wire removed

6) Screaming Demon free-flow exhaust

Thoughts:
The bike runs Noticeably better.
Smoother, faster power through the whole rev range, shifting down a gear is a LOT smoother and less likely to lock the rear tyre at high rpm. For some reason I am a little disappointed... but there is no question the bike is quicker, smoother and a lot more torque under 5,000rpm. Top end is also much nicer for passing in the 100km zone.
I am picking I've gone from the stock 28hp to around 35hp which I think is great considering I spent less than $400 for everything and only 5k for the bike (with 3000km on the clock).

If you already have a free-flow or debaffled muffler, modifiying the air box and raising the jet needles is an easy and CHEAP way to get some power. Changing the jets was a lot more tricky and requied a few extra tools.

Hitcher

29th January 2008, 22:16

Please keep this thread on topic and desist from the cheap personal attacks. They do you no credit.

Several off-topic posts have been relocated to the Pointless Drivel thread. If you want to continue that discussion, please do so there. In accordance, of course, with the site's rules, that I urge you to familiarise yourselves with.

Thank you.

Donut

31st January 2008, 09:25

Photo?

I have some red "neons" under mu 50cc scooter to piss off the boy racers :)

will try get a photo on when i fix the camera :doh:

Paul_C

5th February 2008, 11:40

Gubb

7th February 2008, 15:33

Complete re-post, but I figured it's relevant in here too. For those that aren't aware, I recently had my first stack (http://www.kiwibiker.co.nz/forums/showthread.php?t=65725) Only casualty was the Gear Lever, and Indicator.

Got bored in the Waitangi day sun. I figured everyone else was out riding, so I had to have a bike fix anyway.

Managed to pick up everything I needed at Bunnings.
I bought 4 washers, 2 nuts, 1 bolt, 1 piece of rubber tube (5cm), 1 piece of garden hose (5cm).

Drilled a hole in the actual lever, coloured everything black with a Sharpie first, as I at least wanted it to not look like a rangi-mod. Placed a washer onto the bolt, followed by the rubber tubing, then the rubber hose. I wanted to put something underneath the hose as it was too loose by itself. Cut these to length with the Missus' good kitchen knife. Luckily she wasn't home to see this, as I would have ended up wearing the knife. Slid another washer on over the end of the hose, nut, placed it through the lever, another washer, and the final lock nut, and Presto! instant Gear Lever.

Total cost, $2.60 and 15 minutes. Much cheaper than the $100 it would have cost me to buy from a dealer.

Tested it, and the clearance between the lever and the pedal is sweet, works just like a bought one.

Pics Here. (http://www.kiwibiker.co.nz/forums/showpost.php?p=1414129&postcount=13)

nivram

8th February 2008, 14:18

If I'm only fitting an SD Muffler why would I have to re jet? If I was doing the air filter as well then I would re jet.

Gubb

8th February 2008, 17:26

I have had no issues with the Muffler and not re-jetting, that was about 3000Km ago now, and no issues yet.

However I am planning on getting the Airbox done, and re-jetting at the same time.

nivram

8th February 2008, 19:51

Same I've been running SD muffler without an re jetting and the bike runs fine not too lean at all.

Gubb

8th February 2008, 19:56

I had mine checked after I put it on to see if it was running too lean, the Mechanic said it was sweet as, but as soon as you go and modify the air-flow, and don't re-jet, you will have problems.

nivram

8th February 2008, 20:20

Just removed the wire hope it resolves the flat spot, has to be the quickest easiest mod ever!

Filter_nz

8th February 2008, 22:43

Hey Filter,

Just put my order in for a Screaming Demon pipe and will be ordering a new air filter in a few days.

Just a quick question, how much did you pay for your rejetting kit? Obviously the kit you bought had the correct settings etc included?

How much did it cost?

Does anyone know how much it would cost to get rejetting done at a dealer?

Cheers for your help.
Paul

hmmm not sure I want to tell people, I want the fast Hyobag around town.
Seriously though, I got it for about $90nz inc shipping from EBAY.

It took me about 4 hours to do and unless you remove the carbs altogether you'll probally strip all the screws :(

If you take it to a mech they'll probally drop the jet needles down one position and call it a "rejet". And to be fair it'll work... doing that increases mid range fuel flow which is where you'll have the bike when curising... and so won't be running lean. Just dropping the needles is a cheap, easy and safe way to make sure your straight through and air filter don't lean you out. Will gain a bit of power too. You can do it youself if you want me to explain.

If I could to it all over again I wouldn't have bothered with the jets themselves.

xwhatsit

9th February 2008, 01:28

Well, as you've listed the jet sizes, no need to pay $90. Simply work out what type of jets you need (what brand carb? Keihin? Long hex-head jets or small hat-style?), and order the appropriate jets from your local dealer. I payed $7 for a single hat-style Keihin main jet. $90 is quite a mark-up on $14.

Maki

12th February 2008, 13:41

Save every last cent you would use to mod your 250 and spend it on a bigger and better bike later. That way you will get a hell of a lot more bang for your buck. I expect I will keep my 250 bone stock.

Did you ever notice that people shopping for used bikes prefer a clean stock one that has been maintained by the book to a blinged out version?

Gubb

12th February 2008, 14:44

Not everyone intends on getting rid of their 250 once they get their full license.

Vetran

12th February 2008, 16:04

Also if you were really worried about saving money for your next bike, you would not by a new one, as it will depreciate far more than a used bike.

325rocket

12th February 2008, 17:52

Not everyone intends on getting rid of their 250 once they get their full license.

spoken like a true scaredy cat :baby:

just kidding, im keeping mine too

Gubb

12th February 2008, 17:56

:bleh:

Plan is to keep the Hyo as a commuter. $25 for 350K's? Can't go wrong.

The other bike shall (A Speed Triple - one day...) come out at the weekends.....

Weaver

12th February 2008, 19:11

I want to get a R6 as soon as I get my full. I don't know weather I'd sell my Hyosung, depends on what its worth when the time comes.

If I didnt wish I could be nimble, then I'd see no need to upgrade.

Tall Learner

15th February 2008, 14:35

That's exactly what I did - only a little neater. Didn't actually 'Cut" the wire, just removed it from the plug and insulated it. If anyone wants to do this but is worried about getting the wrong wire try this:

Hyosung GT250/R 2006/7 (NZ new imports)
1. Open up the seat.
2. Un bolt the CDI unit. (small black brick next to the relays)
3. Disconnect the Brown plug from the CDI. BE GENTLE.
4. Get a very small Alan key - preferably one that will fit into on of the circular holes in the 'male' end of the brown plug.
5. Locate the Green/Blue wire.
6. This wire should be in the same position as in Pancakes photo - if it is in a different position DO NOT REMOVE.
7. Use the alan key to carefuly push the copper contact out of the plug. It should pop out the other side with the wire, blue plastic bung, and copper contact all in perfect condition.
8. Tape up the end of end of the copper contact VERY thoughly with electrical tape. If you have some kind of plastic insulation to cover it as well I suggest using that.
9. Tuck the loose wire back into the loom.
10. Reattach the CDI.
11. Power up the bike but DONT start it. Check all your lights work, and check the digital dash if you have one.
12. If everything works fine continue - if anything has stop working then stop here - you've fucked up.
13. Fire up the bike. Let it idle. Listen for anything odd - firing on one cylinder etc... normal? Good!
14. Test the kill switch. If it doesn't work, you fucked up.
15. Everything works go ride the bike. You should notice a VERY smooth power curve now.

Dunno if this has already been asked, cant b f'd reading it all. But does this work for The GT250???

Weaver

15th February 2008, 14:53

.... I would imagine so....you could try and let us know, then when the next GT owner asks we will have a definate answer.

Gubb

15th February 2008, 16:21

Yes it does, exactly the same engine and electrics.

Iain

18th February 2008, 09:00

Dunno if this has already been asked, cant b f'd reading it all. But does this work for The GT250???

Worked VERY well for me :) Its a non-permanent fix, so you can always plug the cable back in if you arent happy.

Give it a try, I was happy. No more 5000-6000k flat spot and much smoother shifting.

Iain

EDIT: Oops, just realised I didnt answer your question at all.

nivram

22nd February 2008, 20:26

I have a GT Comet 2007 and it fixed the flat spot problem for me.

CookMySock

22nd February 2008, 21:43

does mod work for the 2008 GT250R ?

TIA,
DB

jcupit69

23rd February 2008, 00:18

Not everyone intends on getting rid of their 250 once they get their full license.

True that, i'll never sell my rs. There are afew others on here that are the same (with there rs's n rgv's neway)

Considering your mods have cost less than $500 id say its well worth it! Rode a mates stock hyo and was not impressed, but did get the feeling it wouldnt take much to make it noticobly better. Would be really interested to see what a moded one feels like compared to the stock one i rode.
Congrats :clap:

Bling your way for the clever moding and the help your giving, well done keep up the good work :niceone:

EnzoYug

24th February 2008, 15:41

does mod work for the 2008 GT250R ?

TIA,
DB

Absolutely.

Radar

29th February 2008, 21:41

http://www.richardhyosunggvgt.com/cometgt125250650rs.htm

Hey deano and enzo - I want to thank you for this link:
http://www.richardhyosunggvgt.com

I emailed Richard (in Korea) about getting a (rear) shock absorber and he emailed right back - that guy is FAST, like one minute to reply. He let me know when the deadline was for making the Friday delivery and I managed to get in and the shock - plus two other small bits - was sent and could arrive as early as Monday, possibly Tues or Wed. Wow, that is QUICK service - we need more internet businesses like Richard's. :cool: Oh and yeah, his prices, including shipping, are really good! :2thumbsup

BTW, I thought I needed a new CDI (cannot remove a wire on my model cuz there is only ONE wire in the brown connector) so took it to our local Hyo mechanic so he could test drive my bike. The good news is he says there is no flat spot and it runs really well, but the bad news is that it needs a new rear shock and the price the shop gave me was waaaaay too high.

deanohit

1st March 2008, 07:59

Glad to help man.

Radar

3rd March 2008, 09:33

The Pastor

3rd March 2008, 10:48

for best gains you rejet when you change something, like air intake and exhaust flow. more air goes in, more fuel can fit. etc etc.

rickjames

3rd March 2008, 11:05

The main reason to read this thread is for info on modding your Hyosung CDI unit for better response / eliminating the famous 3'rd gear flatspot..**

This thread is all about my sexy GT250R, or at least it will be - I'm starting to customise it now that I've hit 8,000k without the slightest problem. So here's a list of what I've done so far and what needs doing. I'll update as I go.

What I want is any advice other bikers, particularly any Hyobag owners might have on these:

I thought these would come fairly wanked up already after reading the marketing speel?

"Ready to race, ready to ride. The GT250R is a full size race tuned bike with looks to match. Fully equipped with rollerized V-Twin high output DOHC 8 valve engine, race tuned suspension including inverted forks and gas charged shock absorber, huge brakes, stunning aerodynamics, complimented by digital instruments and adjustable ride position. Whether you're starting a race career, riding for fun or just getting around, the GT250R is ready to take you where ever you want to go.
Dual lens headlamp and aerodynamic fairing are stylish and functional. A tinted windscreen is available as an optional extra. Race position handlebars and adjustable footrest positions give the rider flexibility to tailor the ride position to rider preference. "

http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Motorbikes/Sports/auction-135772858.htm?p=1

EnzoYug

3rd March 2008, 11:08

Marketing speel is for chumps.

It's the price tag, and the word of other bikers that'll truly tell you what you need to know.

Iain

3rd March 2008, 11:09

Hey guys, whats the deal on REJETTING carbs? Does it really increase performance, and if so, it must be be at the expense of fuel consumption, right? How much does rejetting cost? Is rejetting only done when a different exhaust system - muffler - is installed?

Ive just put a Screaming Demon exhaust on and will talk to the guys at JFK about dyno and rejetting as well as whatever airbox modification they need to make.

I spoke to someone who the the same thing done at JFK and he said the before and after dyno showed an increase of 10HP. Not sure if it was 6 and he just rounded to 10 :shifty: But Ill let you know how it goes.

Iain

Radar

3rd March 2008, 12:26

Just found this (which could help doing mods):

The workshop manual:
http://www.hyosungcomet.com/archivos/manual_250.rar

OK, yes I know its for a Comet, not a GTR, but the mechanics are basically the same.

Anyone know where to download other Hyo workshop manuals?

Radar

3rd March 2008, 13:11

Hey deano and enzo - I want to thank you for this link:
http://www.richardhyosunggvgt.com

I emailed Richard (in Korea) about getting a (rear) shock absorber and he emailed right back - that guy is FAST, like one minute to reply. He let me know when the deadline was for making the Friday delivery and I managed to get in and the shock - plus two other small bits - was sent and could arrive as early as Monday, possibly Tues or Wed. Wow, that is QUICK service - we need more internet businesses like Richard's. :cool: Oh and yeah, his prices, including shipping, are really good! :2thumbsup

The shock just arrived - ORDERED Friday afternoon, DELIVERED Monday - amazingly quick service from Korea to Masterton. I am impressed.

So if you guys want to do mods, I recommend that you order from Richard in Korea.

Also came with the shocks - two sets of over-handlebar-grips hand warmers - one set for my friend. Very good quality and only $27 NZD (without shipping since they had a free ride with the shock absorber).

325rocket

3rd March 2008, 17:30

I spoke to someone who the the same thing done at JFK and he said the before and after dyno showed an increase of 10HP. Not sure if it was 6 and he just rounded to 10 :shifty: But Ill let you know how it goes.

Iain

i think youll find its 10 DB not HP

;):lol::dodge:

EnzoYug

3rd March 2008, 22:24

i think youll find its 10 DB not HP

;):lol::dodge:

Ha, alot more than 10DB.... :D But yeah, you can take they Hyo's quite close to 40HP if you put the work in. A lot more than just pipe and carbs tho...

Rev DJ

13th March 2008, 12:24

CookMySock

13th March 2008, 12:47

I cant understand why this mod isnt done by the bike shop before the Hyo's are soldI read it was an emissions thing. Dunno where sry.

DB

CookMySock

13th March 2008, 13:07

Ok time to update.. It took me about 4 hours to do but it's done.cool to read about your mods. Have you noticed any difference in the fuel economy yet ?

thanks,
Steve

Iain

13th March 2008, 22:37

Wow - did the CDI mod last night just before the Wednesday night Wellington run - Woa what a difference. Followed the description on this thread - took a couple of minutes and then :2thumbsup

I cant understand why this mod isnt done by the bike shop before the Hyo's are sold? Good pick-up and power band - bike is performing as I had hoped now :woohoo:

Cheers DJ

I does make a difference doesnt it. Much smoother changing gears as well. I was told that it was an emission thing. It retards the timing through the rev range to reduce emissions... Unfortunately it seems to cause a flat spot between 5-6k rpm. Since we dont have vehicle emission testing like in California and Canada we get away with eliminating this 'feature'.

Works a treat though eh!!

Iain

Rev DJ

26th March 2008, 09:14

Iain

26th March 2008, 09:32

I've been running my bike after doing the CDI mod (two weeks ago) and this week it seems to have really picked up in terms of performance - much more zip and torque. The CDI mod definitely made a difference initially but the last couple of days have been better again - WEIRD...

I was wondering if the Hyo has any form of engine management or is the CDI purely a hard-wired ignition system? (Or it may be a case of my bike running-in and getting better with the Km's.) Thoughts... DJ

How many K you done now? I noticed that while I was breaking it in (1600+km) and even towards the end it felt like it didnt want to see the top half of the rev range. After breaking it in according to manufacturer's guidelines it was more than happy to hit redline!

Iain

Radar

28th March 2008, 09:14

Iain

28th March 2008, 11:43

Thought someone may be interested in this:

GT250 & GT250R HYOSUNG PERFORMANCE KIT

US $58.95

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=220210823638&ssPageName=MERC_VIC_ReBay_Pr4_PcY_BIN_Stores_IT&refitem=220189256573&itemcount=4&refwidgetloc=closed_view_item&usedrule1=CategoryProximity&refwidgettype=cross_promot_widget&_trksid=p284.m183&_trkparms=its%3DS%252BI%252BSS

I was looking at getting a set of those. But then decided that I will just send it to JFK to get put on the dyno, before and after, jets and airbox mod. Spoke to them about it and they mentioned $300 approx.

Iain

Rev DJ

28th March 2008, 12:17

Just gone thro 2,400k's...

So, is the CDI hard-wired? Can it be altered? Cheers DJ

Iain

28th March 2008, 12:22

Just gone thro 2,400k's...

So, is the CDI hard-wired? Can it be altered? Cheers DJ

You quite easily use a flat head watch screwdriver (one of those really small ones) to press the tab back so you can pull the wire from the back of the plug. To re-connect just pull the tab and put it back in the same part of the plug and the tab will catch again.

Iain

Gubb

28th March 2008, 12:31

I was looking at getting a set of those. But then decided that I will just send it to JFK to get put on the dyno, before and after, jets and airbox mod. Spoke to them about it and they mentioned $300 approx.

Iain

Have you had the work done yet? Noticeable improvement?

Iain

28th March 2008, 12:45

Have you had the work done yet? Noticeable improvement?

Havent had it done yet... I need my bike everyday so finding a day I dont need transport is what Im waiting for.

I spoke to a few people and they suggested 10 more horsepower - at least that is what they got when they did the work. That is pretty significant - 33% more. Dyno before and after showed that. I will post my dyno results when they are done.

Iain

Radar

28th March 2008, 14:48

send it to JFK to get put on the dyno,

What is JFK ?

Gubb

28th March 2008, 14:50

Bike shop.

Iain

28th March 2008, 14:53

What is JFK ?

Oops sorry, http://www.jfkjetskisandmotorcycles.co.nz/

The place I bought my bike :)

Iain

Paul_C

14th April 2008, 22:39

Finally!

Hyo GT250: Check
Carbon Fibre exhaust: Check.
BMC High Flow Filter: Check.
Re-jet and tune: Check.
Other repairs due to own stupidity: Check.

I honestly can't believe the difference to the sound and the performance these mods make. I feel like my bike actually has a bit of personality now! People actually look when the hyobag trundles down the street. I'm so happy.

If there's anyone out Manawatu ways that wants to help me gently bed the engine back in and go out for a ride after a half a year off riding post here. I've still got 800km to go before the engine will be back to 100% but i'm well keen to get back in the saddle and go for a blat.

Gubb

14th April 2008, 22:54

Yeah, the re-jet certainly makes a difference.

CookMySock

15th April 2008, 09:21

Yeah, the re-jet certainly makes a difference.Does this knock the fuel economy at all ?

ta,
DB

FilthyLuka

15th April 2008, 10:03

Does this knock the fuel economy at all ?

ta,
DB

High flow air filter means the engine can suck in more air, so you need bigger jets to supply more fuel due to the larger amount of air.

So i guess fuel economy would go down, but in my experience, re-jetting doesn't hurt the fuel economy noticably, i got 220km on the GN before rejet, up the mains and needle and i got 220km after.

So in theory, yes. In practice, not really

Gubb

15th April 2008, 16:27

Dunno yet, only had it done last week, haven't gone through a tank yet.

The extra power is certainly noticeable. All low-end/mid-range, much nicer for zipping around town, no noticeable difference to the top end. Dyno says it's another 10HP up from factory after the work.

Iain

15th April 2008, 21:33

Gubb

15th April 2008, 21:49

JFK
</10 char>

Iain

15th April 2008, 21:53

JFK
</10 char>

Brilliant... Thats where I got my bike. How did you find them? Did they supply the air filter also? Can I ask how much it was all up?

Iain

Gubb

15th April 2008, 22:05

Yeah, they did the Filter and the Airbox. $480 all up including a service.

Iain

15th April 2008, 22:09

Yeah, they did the Filter and the Airbox. $480 all up including a service.

oh good... Im 700km off my 8000k service... so I am waiting for the same thing... How many K you got on yours?

Iain

Gubb

15th April 2008, 22:17

Had 9800Km on it when I took it in for it's 8000Km service (whoops...)

Just clicked over 10100Km today.

Iain

15th April 2008, 22:20

Had 9800Km on it when I took it in for it's 8000Km service (whoops...)

Just clicked over 10100Km today.

Thanks mate... Looking forward to the increase in HP. Did you mention any names when you went to JFK?

Just hope the weather improves so I can take it for a long ride...

Iain

Gubb

15th April 2008, 22:28

Can't remember any names, but the main mechanic is pretty clued up (as you'd hope!) and a good guy to shoot the shit with.

xwhatsit

19th April 2008, 15:57

High flow air filter means the engine can suck in more air, so you need bigger jets to supply more fuel due to the larger amount of air.

So i guess fuel economy would go down, but in my experience, re-jetting doesn't hurt the fuel economy noticably, i got 220km on the GN before rejet, up the mains and needle and i got 220km after.

So in theory, yes. In practice, not really

Well... sort of. You've got more air -- so you add more fuel. So now you've got more air and fuel. So, perhaps, at half throttle, you'll be getting the same amount of air and fuel that you used to get at half-throttle-and-a-bit.

So, you can see, in theory, it just shifts things around a bit. Unless you're running everywhere at full throttle (provided the engine can even suck in that much fuel/air -- you run into cams and valve work there), you won't use more fuel.

quackquack

24th April 2008, 13:15

Has any one seen this wreck. Can't believe it was written off http://www.trademe.co.nz/Browse/Listing.aspx?id=150915251

Weaver

24th April 2008, 18:26

Has any one seen this wreck. Can't believe it was written off http://www.trademe.co.nz/Browse/Listing.aspx?id=150915251

Could be a bent frame or a damaged motor perhaps.

CookMySock

24th April 2008, 18:41

Has any one seen this wreck. Can't believe it was written off http://www.trademe.co.nz/Browse/Listing.aspx?id=150915251

I'm gunna go look at it next week. My 14 y/o kid will bid on it if it's rebuildable. Hez got a job today so hez on his way.. Good lad!

DB

quackquack

29th April 2008, 10:41

I was in looking at the VFR that went yesterday and it looks pretty good might be a good one if you don't have a bike.

CookMySock

7th May 2008, 12:05

which brand aftermarket exhaust can has the best sound ? Has anyone put these side-by-side ? Some of them sound like a dog with a blocked nose barking down a huge drainpipe. Yuck.

I got a 250R and a 650R to change over.

TIA,
DB

Gubb

7th May 2008, 18:24

Here's mine:
http://www.youtube.com/watch?v=xt3L03l0jlQ

Rev DJ

8th May 2008, 22:54

[QUOTE=DangerousBastard;1552597]which brand aftermarket exhaust can has the best sound ?

Cycleworks - straight thru - barks and burbles...cool. Very well made too.

Cheers DJ

Rev DJ

19th May 2008, 15:13

Hey, has anyone seen a good rear hugger for a Hyo? :hug: I'm looking for a carbon fibre one... Are there any that are available locally? Cheers DJ

Gubb

19th May 2008, 16:37

These guys do 'em. (https://www.ngales.com/products.asp?cat=21&sub=12&type=accessories)

Expensive though, NZ$178 for the Painted one, and NZ$330 for the Carbon Fiber model. Plus Postage.

Weaver

19th May 2008, 20:05

I'm selling my GT250R tail tidy if any one from the Wellington region is intrested in buying it. Very easy to install, only need to drill two holes and cut/join a wire. $60 and if the installation is a bit beyond you, I can help.

Gubb

19th May 2008, 20:09

You selling other parts from the bike, or as a complete unit?

I'm keen on the rear sets if they are available.

Weaver

21st May 2008, 19:50

Na, thats all I got left

325rocket

21st May 2008, 21:19

You selling other parts from the bike, or as a complete unit?

I'm keen on the rear sets if they are available.

what happened to yours? scraping pegs ;)

:wari:

Gubb

21st May 2008, 22:34

Nah, from the first crash I had, I made a budget home replacement job which i'm pretty happy with, but I figured if a cheap set was going...

omrimon

28th May 2008, 06:49

Nah, from the first crash I had, I made a budget home replacement job which i'm pretty happy with, but I figured if a cheap set was going...

Can you post a pic or an explanation of how you fixed your rearsets?

I already managed to brake a brake lever and bend another one, broke the right rearset and footpeg twice as well.

It's like these things are made of pudding.

Do you guys reckon a pair of aftermarket rearsets would hold up better in a crash?

ArcAngellives

31st March 2009, 20:47

Just one question, how on earth do you get your bike up to 160 km/h ?
I can't get more than 130 km/h out of mine (naked, full throttle, chest on the tank in top gear). Is my bike rooted or am I too fat (75kg) ?

Man thats real weird i have had myn up to 168 km heaps of times and i weigh 108kg

but i wouldnt advise it the cams are starting to rattle alot now :(

Gubb

31st March 2009, 20:54

Fairings help.

That said. Real men ride Naked.

DarkLord

2nd April 2009, 12:56

Man thats real weird i have had myn up to 168 km heaps of times and i weigh 108kg

but i wouldnt advise it the cams are starting to rattle alot now :(

Totally n00b question here -

Where are the cams on the Hyo, what do they do, and where would the rattle be coming from if it was them?

Thank you for helping to increase my mechanical knowledge :)

CookMySock

2nd April 2009, 20:31

Where are the cams on the Hyo, what do they do, and where would the rattle be coming from if it was them?You should find a parts manual for your bike and you will see where everything it.

The rattle comes from a slack camshaft drive chain, or worn shims, or any number of other little things.

The cams are under the cover on the top of the cylinder heads.

They open and close the cylinder valves to allow air/fuel in, and exhaust out, at the correct times.

Steve

Gummie

12th April 2009, 21:26

ok have removed said wire myself too
since i have bought my bike i have noticed this lag as i would put it.
I think it was just my confidence increasing that made me notice this lag from 5k to 6k more and more but i was going to mention it at my next service as i was thinking it may have been a fault.
After reading this thread i now think otherwise.
but now that i have removed it i have not had the chance to ride :angry: which is very unsettling as i like to test modifications :bash: as any red bloded biker would

bloccrule

5th June 2009, 17:25

Generally I agree with all the advice.
The jet kit I purchased includes the air filter and instructions for the air box modification. It also includes various tools and instructions to de-baffle the stock exhaust. The seller says it took ages to perfect the combination and will not tell anyone what jets etc he's gone with. I checked with other customers who can't rave enough... so fingers crossed. I'm pretty savvy with working on car engines and have most of the tools so shouldn't be a prob.
I'll photo document the kit and the install for anyone interested..... unless it blows my bike up and totally running like rubbish, in which case I will lie to you all and say how awesome it :whistle: to avoid the "I told you so's" seems u bought the same kit i did off ebay. i have done every thing but the part where it say u have to the air/fuel screw may be covered by a brass plug due to EPA regulations. drill that out if needed but be careful. start with 2 turns and increasing by 1/2 turn. what in the world does this mean. where is this brass plug at on the carbs. the pictures he sent with my kit does not show u where this plug is at. can u help me

CookMySock

28th June 2009, 16:43

Just put a noisy zorst on one of the GT250Rs. Now to get it's mixture checked. I might take both of them in there and get them to A-B them and see if they are different.
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Steve

chaos rider

29th June 2009, 14:53

Hey, has anyone seen a good rear hugger for a Hyo? :hug: I'm looking for a carbon fibre one... Are there any that are available locally? Cheers DJ

um the one i have is awsome but its a one off custom a mate got made for his hyo. and sold it to me when he got sick of crashing

Hiflyer

2nd July 2009, 01:29

far out man no one on youtube revs their bike high when showing off their exhaust haha

CookMySock

2nd July 2009, 08:12

far out man no one on youtube revs their bike high when showing off their exhaust hahaThats coz it sounds ghey.

Steve

Hiflyer

2nd July 2009, 17:51

uuummm ok? haha whats ghey about hearing a vtwin or nice exhaust at full song?

CookMySock

2nd July 2009, 20:28

coz its posing.

Steve

gatch

4th July 2009, 10:37

Go on DB

Get a perrm

streethot

7th July 2009, 14:54

Hi there.....I am from brazil and there are a good qtd of gtr250 over here.....

i am looking foward to improve performance......i know its easy to buy a new bike.......but I likey to put my hands on the work.....all my cars have mods....

i have done so far:
1)carbon exhaust
2)cut wire on the cdi

what i am developing
1)new air filter
2)jetting

we dont have jet kits like that on ebay......but we figure it out with parts from other carbs......

someone have done some head porting on these motors?

streethot

7th July 2009, 14:56

CookMySock

7th July 2009, 15:16

and.....

the vaccum that pull fuel pump came from one intake (rear intake), i wonder if i put a " T" conection to pull from both intakes would be better for fuel balance......or it could do any good at all?No, that hose only opens the fuel valve on the tank.

If you want to go faster, the best mods to do on the GT250R is front and rear suspension. Most of the problems with the GT250R are because of its bumpy ride in corners. Change the rear shock and fit cartridge emulators to the forks.

Steve

streethot

8th July 2009, 07:41

Can anyone tell what jetting and carb settings are you using with mods like muflers and new air filter.....?

CookMySock

8th July 2009, 08:10

Can anyone tell what jetting and carb settings are you using with mods like muflers and new air filter.....?I just put a two inch straight-through muffler on, and with the jetting standard it's slightly harder to start cold or hot (needs a blip of throttle.) Also the tailpipe is running VERY clean. I think it's a tad lean, so I'm going to get it checked on the exhaust gas analyser and maybe raise the needles with the clip or a shim. I'm not trying for more horsepower - just trying to make sure that the engine is not harmed.

Will report back.

Steve

streethot

8th July 2009, 12:09

just tested on street.....

new jets
hi flow air filter
carbon exhaust
wire mod

nice ride......12k rpm easy......could use more advance or something......

on downtown streets only went to 3rd gear at full throttle.....

i am one more very happy GTR250 owner!!!!!!!!!

woodhillkamikaze

26th July 2009, 09:43

woodhillkamikaze

26th July 2009, 09:45

I had my blue green wire pulled out and then realised that the bike performed better with it in. Talk to the guys at Mt Eden Motorcycles (they are Hyosung Dealers) they'll confirm that pulling the wire out is BS. It goes better the way they built it!

I had lags etc when changing gears which was very annoying to say the least. Now that the wire's back in it rides like new!

Hiflyer

26th July 2009, 09:59

thats cos you dont have a hyosung...

It could be different for a kawasaki

arno

30th July 2009, 09:33

Do you know where I can find a brake lever for a Hyosung Gt250r mate? Mine snapped off like a twige

Jonno.

30th July 2009, 11:13

Cycle treads, Mt Eden motorcycles... Where do you live.

325rocket

30th July 2009, 13:47

Do you know where I can find a brake lever for a Hyosung Gt250r mate? Mine snapped off like a twige

jump on korider.com and have alook around. you will find some good info

chaos rider

30th July 2009, 16:45

do yourself a faver and get a new aftermarket brake master and lever set the hyo one is shit well the lever is at least

ive used 3 now 2 of wich broke in my hand not from the crash

wanpo

5th March 2010, 10:44

I might pull my CDI wire tonight, or at least take a look.

I've got a couple of #100 main jets and a high-flow K&N filter sitting at home to be installed this weekend. I'll let you know of the results when it's done.

What does JFK charge for a dyno + fuel/air run? The place I got my filter from said $140.

Any idea what they do with the 'airbox mod' at JFK? is it just a desnorkling of the stock filter?

I'm going to cut up the stock airbox to fit my new filter in there so that she's still weather proof.

Eaan

25th April 2010, 22:43

That's exactly what I did - only a little neater. Didn't actually 'Cut" the wire, just removed it from the plug and insulated it. If anyone wants to do this but is worried about getting the wrong wire try this:

Hyosung GT250/R 2006/7 (NZ new imports)
1. Open up the seat.
2. Un bolt the CDI unit. (small black brick next to the relays)
3. Disconnect the Brown plug from the CDI. BE GENTLE.
4. Get a very small Alan key - preferably one that will fit into on of the circular holes in the 'male' end of the brown plug.
5. Locate the Green/Blue wire.
6. This wire should be in the same position as in Pancakes photo - if it is in a different position DO NOT REMOVE.
7. Use the alan key to carefuly push the copper contact out of the plug. It should pop out the other side with the wire, blue plastic bung, and copper contact all in perfect condition.
8. Tape up the end of end of the copper contact VERY thoughly with electrical tape. If you have some kind of plastic insulation to cover it as well I suggest using that.
9. Tuck the loose wire back into the loom.
10. Reattach the CDI.
11. Power up the bike but DONT start it. Check all your lights work, and check the digital dash if you have one.
12. If everything works fine continue - if anything has stop working then stop here - you've fucked up.
13. Fire up the bike. Let it idle. Listen for anything odd - firing on one cylinder etc... normal? Good!
14. Test the kill switch. If it doesn't work, you fucked up.
15. Everything works go ride the bike. You should notice a VERY smooth power curve now.

Extra for experts: Go buy a nice big exhaust, or get yours debaffled. Then get a new air filter, then get it re-jetted. (being cheap and not getting the re-jetting will fuck your bike in the long run) Enjoy the most powerful Hyobag on the block.

A great guide that seemed plausible, so I went outside today and cut the green/blue wire. Everything worked and it seemed to have more power in the mid-register. But it could also be a placebo since this is the first ride this year.¨
But I did not however disconnect the brown wire... Will this affect performance/reliability in any way?
Oh, and I got the 125cc version with 15 hp, if that matters to this mod.

Gubb

25th April 2010, 23:25

Never cut. Disconnect. Don't do anything you can't reverse in 5 minutes.

wanpo

26th April 2010, 11:30

What Tires are good to chuck on the GT250R?

my shitkos are reaching the end of their (short) lifespan, ~11k km

Gubb

26th April 2010, 11:42

BattleAx

10motherfuckin'char

kolio

9th June 2010, 23:28

hi!
i am from ukraine. I have hyosung gt250R 2006 year and i have some problem on 3-third step on 5700 rpm
2 hours ago i disconect green-bkue wire and after work i will try modification

YYESSSS!!! I HAVE NO PROBLEM ANYMORE WITH 6000rpm. ENGINE IS A ROCKET :)

but my friend have this problem and he not have green-blue wire on CDI. he have old old CDI ? we dont understand what do with hes CDI

coggle

10th August 2010, 15:39

You would need to be doing something real wrong for it to fuck it up catastrophically, will probably just run a bit dodgy.

Now that you've done the easy stuff, you can:

1) Port and Polish, all you need is some carbide bits, a marker pen, some gaskets, some time, a micrometer, a telescopic lever thingie that pops out and measures inside diammeters (cant remember what it is called), some more time, a scriber... okay you need alot of shit, but thats not the point!
2) skim the head, find out the distance between valves and piston when they are closest together, skim head appropriately. Or skim even more and mill the piston...
3) Mirror polishing, lots and lots and lots and lots and lots of sanding...
4) high compression pistons... you know you wanna
5) 50/50 mix of 101 race fuel and 98

acceleration and all...

I've done 2 of the above (port and polish, mirror polishing), cleaned out the engine, debaffled the exhaust, put a velocity stack on the carb, jetted the carb appropriately, added some fancy HT leads and a big arse fuck coil too. added tooth on front sprocket. I've seen 150km/h according to Mr. GPS and got there pretty quick. Round town is perfect, sits at about 5500rpm at 100km/h. Dyno run said 36hp at the wheel.

Did i mention this was on a gn250?

All fun and games eh :D

But seriously, who cares about top speed? i mean, 150, sure, woohoo, zx10 does 280 without caring...

Have fun with your bike, don't blow it up now ;)

Denis

Hey guys,

Just read the post, does anyone know if this mod will also work on the GV-250? from what I know they are the same engine. Just wondering if they run the same type of CDI setup.

Rai

14th January 2011, 20:54

hey mate, iv got a gt250r 09 hyosung, im tryna find where in auckland i can get re jeeting kits. iv just got a new demon can, wana run it with out the baffell, before i got it i opened my air box intake just the stantdard box and moved the needle settings back to to highest point. riding home today she lost power on motor way at 7grand. any ideas or info would be really appreciated.

Rai

14th January 2011, 21:02

howsit? does any one have any info on where i can get re jetting kits? and how much do they cost? brought the demon can, wiped off baffell, riding on motorway around 7g it lost power and cut out on me, before i fitted the can, i modified the original air filter box opening it rite up to allow more air intake, then set the needle settings to its highest point, running the demon is not working, so shes parked in the shed. does anyone have any info, comments id appreciate it.

Gibbo89

15th January 2011, 18:20

slan_mark

16th June 2011, 12:57

Hey,

Does anyone know how to check the type of bulbs on this machine without stripping her? I've seen a site where I can buy 4300k bulbs without have to install a convertor. Just want to get rid of the current lights and improve my vision at night at the same time getting it to look better at low cost. Is it possible to install repco H1 bulbs without having to get a convertor too. Sorry new to the game so not really where to go.

This is the site for the head light kit.
http://www.epfguzzi.com/hyosung/accessories/gt250.html

G4L4XY

14th March 2012, 17:44

Just one question, how on earth do you get your bike up to 160 km/h ?
I can't get more than 130 km/h out of mine (naked, full throttle, chest on the tank in top gear). Is my bike rooted or am I too fat (75kg) ?

Fatty!!! Try changing to 5th? My hyo goes up to like 160 before I start hitting the redline

Ewww I just realised how old this post is, meh.

I'm gonna try the CDI mod as the flat spot is retarded, trying to beat all the traffic at the lights is so lame, as soon as I get to third I have to instachange to 4th to get out of the flat spot but being in 4th = no acceleration, of course by then im at 50kms anyway, this could also relate to accelerating on the open road too so same story..

DrunkenMistake

17th March 2012, 18:32

Fatty!!! Try changing to 5th? My hyo goes up to like 160 before I start hitting the redline

Ewww I just realised how old this post is, meh.

I'm gonna try the CDI mod as the flat spot is retarded, trying to beat all the traffic at the lights is so lame, as soon as I get to third I have to instachange to 4th to get out of the flat spot but being in 4th = no acceleration, of course by then im at 50kms anyway, this could also relate to accelerating on the open road too so same story..

Just get the 650.
By the time your in 3rd your doing double the posted speed limit.
No need to worry about a low range flat spot.

nzspokes

17th March 2012, 19:10

Got a mate with a GTR250. How hard are the shims to check, its up for its 15k check.

launcht

18th March 2012, 08:32

Has anyone done this to the new 2012 versions of GT250r, or is the mod more for the non EFI bikes?

bc.worldlive

21st March 2012, 20:53

wow! she sounds hott!
i ride a stock standard 06 gt250r, i'd love to see the result!!

G4L4XY

28th March 2012, 17:28

Just get the 650.
By the time your in 3rd your doing double the posted speed limit.
No need to worry about a low range flat spot.

I can't afford it lol and when I upgrade im not getting a hyobag no no no!

DrunkenMistake

28th March 2012, 17:55

I can't afford it lol and when I upgrade im not getting a hyobag no no no!

Nothing wrong with it,
By the time I get a new bike, I will be so used to the Hyo tank that a lighter bike will be like a push bike in comparison haha

francewavidok

17th August 2012, 09:52