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Offline twosmoke595

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Official 2009 KTM 125sx bike build
« on: August 29, 2012, 02:28:00 AM »
some of you may have seen my other thread about getting this bike but for those who haven't here is a little rundown.

its a 2009 ktm 125sx bought the bike for 1500, as is, does not run, when kicking it over the crank on the right side definitely has a noise it shouldn't have, it came with the title, all paperwork. As far as i can tell the only aftermarket parts on this bike are the fmf factory fatty and the shorty silencer

got a little time to tear into it today, and so far it looks like the bike is just super dirty and in need of a good cleaning, I'd be surprised if it has ever seen soap and water

here she is before tear down


one thing i noticed when taking it apart is that there is actually very little hardware compared to jap bikes, this being said, this is the first non jap bike Ive ever owned. So everything is going to be a little different

here is a little shot of the motor


a shot after finally managing to get the seat/side plates/rear fender off


there is only 2 bolts, one on each side of the side plate/rear fender combo, and 1 bolt that holds the seat on under the rear fender ( i can already tell that this was a bad idea on ktm's part bc that bolt will get filled with mud/dirt very easily) but overall i'm pretty impressed with the ingenuity of ktm, very simple gets it done design. for instance, i didn't realize that the left air box cover pops off to reveal the air filter GENIUS!! after 40+ years for each manufacturer you'd think they would put something like this on their modern bikes, makes it so much easier than having to take off seat, and jam your hand in the air box and hoping the wing nut doesn't get dropped down in the air box.


my plans are to put a new 12 or 13' front fender and # plate on this bike


again i was kind of surprised at just how little hardware there is on this bike, very simplistic even for a 2 stroke, it seems like there are bolts all over the jap bikes also the bolts on this ktm are pretty much 2 different sizes mainly on the body work and main parts of the bike, pretty sure the entire engine is size 8 and 10 in metric, and the smaller golden bolts are 6's
one thing i also noticed is just how much lighter the seat is on this bike compared to my previous one's (Yamaha yz250, and Honda cr125)


3 bolts later/and one large nut i didn't realize that it needed to be taken off, and the seat/side plates and rear fender were off


the foot pegs are about a half an inch longer and about the same wider than the ones on my previous cr125, which is good for my size 12 boot


pretty cool that these bikes come stock with a hydrolic clutch, tried a yz250 2 stroke that had one and i loved it. only issue is that the paint on the clutch perch is starting to chip off, i think while i have my frame powder coated i'll get the perch done as well


here's the exhaust right when i took it off the bike, i really want a carbon scalvini down the road or maybe I'll just call fmf and buy their titanium end cap that they sell on their ti2, or if i feel like wasting money ask them to make a custom carbon one



i was honestly just thinking of scraping the silencer and pipe bc i was unsure of the condition, but once i got it off the bike i realized that its in great shape, just needed some cleaning, i also plan on getting hi temp flat black paint and sanding the factory fatty down and painting it, as i really don't want to buy another pipe if i don't have to

there's not much a good wash, and the combination of a brillow pad, and some very fine steel wool can't fix and make look like new. Here is the same exhaust after the cleaning



this is all i could get to today

i plan on sending my motor to Michael Soudas who is the TM dealer Cycle Playground in Pennsylvania to get it completely rebuild, and maybe a little port cleanup while he's in there

while the motor is being done, i plan on going to SMS ktm in Denton, TX to get the frame powdercoated orange(as well as some other small bits) also while I'm there trade my stock black wheel-set and some cash for a silver wheel-set (never been a fan of the black rims)

while everything is out I'm going to go over the remainder of the bike start cleaning it up really good, get some orange or blue engine hoses, asv levers, new grips, and hardware throughout as every piece of hardware seems to be rusted

then later on (i haven't decided what I'm going to do yet) possibly get white or orange plastic, with custom graphics done up, also i would like to get a larger see through tank and a headlight for whenever i start doing enduros/scrambles. Been wanting to do them for a really long time but Ive always been too busy to participate.

Obviously its in the beginning stages right now, but more will come very soon
i'm going to try and keep you guys updated as much as possible, as well as keep a price tab (even though i really dont want to see the end price) just so i can show you what can be done when buying a bike that is less than par

also please check out my fb page for updates on me and our race team
https://www.facebook.com/twosmoke595
https://www.facebook.com/pages/TCG-Racin/181481391906041

« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline ridered125

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Official 2009 KTM 125sx bike build
« Reply #1 on: August 29, 2012, 02:52:46 AM »
Two weeks ago, I bought a brand new 2009 KTM 125 SX. It was a leftover. Great price, too. I've been to the track on it once. The manual requires a 5-hour break-in and instructions not to run it wide open during those 5 hours. Really hard to do on a 125!

One thing that jumped out is the motor. It has strong, strong mid and top. Suspension seems fair. The handling is great. If you are in a turn and want to cut deeper, just think about it and you're there. No wiggling, washing or standing up. It corners really well.

Looking forward to your build.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline twosmoke595

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Official 2009 KTM 125sx bike build
« Reply #2 on: August 29, 2012, 03:02:47 AM »
Two weeks ago, I bought a brand new 2009 KTM 125 SX. It was a leftover. Great price, too. I've been to the track on it once. The manual requires a 5-hour break-in and instructions not to run it wide open during those 5 hours. Really hard to do on a 125!

One thing that jumped out is the motor. It has strong, strong mid and top. Suspension seems fair. The handling is great. If you are in a turn and want to cut deeper, just think about it and you're there. No wiggling, washing or standing up. It corners really well.

Looking forward to your build.

cool! thanks for that, been trying to find somebodies input on this bike, (or more than a few inputs actually)
not that it really matters on a 125 but how was low end response?
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline rookie

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Official 2009 KTM 125sx bike build
« Reply #3 on: August 29, 2012, 03:18:02 AM »
i got the 2010 150sx, looks identical

for the seat bolt right under the fender, to prevent mud and stuff
and paste a duct tape over the bolt and there ya got it!

« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline twosmoke595

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Official 2009 KTM 125sx bike build
« Reply #4 on: August 29, 2012, 03:21:33 AM »
i got the 2010 150sx, looks identical

for the seat bolt right under the fender, to prevent mud and stuff
and paste a duct tape over the bolt and there ya got it!

any quirks that you've noticed? anything in particular with the bike that i could change to make better?
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline ridered125

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Official 2009 KTM 125sx bike build
« Reply #5 on: August 29, 2012, 03:31:47 AM »
I haven't taken it out on a trail, so not real sure about low end. On an MX track it's usually wound up enough to pull well out of a turn. Gearing seems a little high stock (13/50).

There's not a lot of info out there on this bike. In 09 everyone was testing and buying the 150. Owner's manual says it has an adjustable ignition. You take off the gas tank and unplug a wire to make it smoother, more of a slick conditions setting.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Stusmoke

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Official 2009 KTM 125sx bike build
« Reply #6 on: August 29, 2012, 10:41:14 AM »
Cool bike now, but dump a grand into it and it'll be a real show pony. Looking forward to the end result
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline twosmoke595

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Official 2009 KTM 125sx bike build
« Reply #7 on: August 29, 2012, 01:14:01 PM »
Cool bike now, but dump a grand into it and it'll be a real show pony. Looking forward to the end result

i'm afraid i wont be able to stop at a grand  :P :P
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline scotty dog

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Official 2009 KTM 125sx bike build
« Reply #8 on: August 29, 2012, 11:22:07 PM »
Can't wait to see how this one turns out, thanks twosmoke, I think doin em up is nearly as much fun as ridin em :D :D
« Last Edit: December 31, 1969, 04:00:00 PM by ' »
F**K THE WHALES......................SAVE THE 2 STROKE!!!!

The hardest part about riding a 4 stroke is telling your parents your Gay!!

05 CR 250

Offline twosmoke595

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Official 2009 KTM 125sx bike build
« Reply #9 on: August 30, 2012, 12:10:16 AM »
Can't wait to see how this one turns out, thanks twosmoke, I think doin em up is nearly as much fun as ridin em :D :D

well all i can say right now is that i'm having doing it lol now whether or not that continues is another story
i like working on bikes, even better when you make a thrashed one new again.

i should be getting the bike down to the frame tomorrow hopefully (fingers crossed) and then taking it to get pc'd as well as sending motor out monday

i'll keep yall updated  8)
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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Official 2009 KTM 125sx bike build
« Reply #10 on: August 30, 2012, 12:13:09 AM »
sending the motor to pro circuit?
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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Official 2009 KTM 125sx bike build
« Reply #11 on: August 30, 2012, 12:15:30 AM »
my bad did not see where till just now.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline twosmoke595

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Official 2009 KTM 125sx bike build
« Reply #12 on: August 30, 2012, 03:58:22 AM »
just a few small updates as i take it apart

she's starting to get naked pretty fast


still amazed at just how little hardware there is on this bike, and the hardware that is there is super light, the shrouds are held on my a handful of plastic screws that weigh nothing, the tank is held on my 1 bolt


i dont really understand ktm's logic by making these fork guards impossible to get off without either cutting them, or having to take the wheel and brake off



im pretty sure ktm didn't put the petcock on backwards so you can't see if its on or off when the tank is on the bike. it had to have been the previous owner


took tank off, didn't realize the bolt in the middle of the tank was holding it on


the only snag that i had was that i need some star sockets/wrenches, the ones that we have are not big enough, and unfortunately it didn't come with the stock tool set, but it came with the stock tool bag...go figure :P


hopefully getting the remainder taken apart and going to denton this weekend to drop off frame, hopefully swap my wheels + cash for a brand new take off set of silver wheels, and probably get a few things sand blasted and/or pc'd
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Stusmoke

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Official 2009 KTM 125sx bike build
« Reply #13 on: August 30, 2012, 08:55:24 AM »
I truly do hate those bloody star drive screws. It just doesn't make sense. By the looks of the dust thats congeeled on the fuel tank there it hasn't been stripped in a while. But on the plus side it looks like you might get a few more hours out of those tires. Looking good mate  8) The shot of that brutal brembo and fat ass rotor would be suitable to an Abrams tank I reckon :P
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline racer142

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Official 2009 KTM 125sx bike build
« Reply #14 on: August 30, 2012, 07:17:35 PM »
Actually my brother Bought an 05 Honda crf250r and the petcock was turned that way and it's how it was supposed to be. The fuel line came out the back and straight to the carb if u turned it around it would kink and wouldn't reach. Said on and off on it and everything u just couldn't see it
« Last Edit: December 31, 1969, 04:00:00 PM by ' »