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Yearly tune up, or not

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Hey guys I just bought a 04 ktm 125sx, my first bike and I'm ready to start riding! I"ve done some basic maintenance like clean/oil the air filter and tighten the chain. My concern is should I pay a ktm dealer to do their yearly tune up/check. They charge about $100. I'm afraid the carb needs cleaning to, so thats another $75. So is it worth paying a shop to do it since this is my first bike and I don't really know what to look and check for. My main concern is that there is a jetting, power-valve or carb issue because the bike doesn't seem to run quite right. There is a little drip of black oil on the tailpipe after every short ride and the guy that sold me the bike left the gas in the tank and carb for about 6 months so i'm afraid there may be some residue in the carb. So would it be worth it to take in for a tune up?

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Adjust the chain as the manual states. KTMs run a little looser then other bikes. A little oil comming out the silencer is ok. Drain the old gas out the tank and carb. Pull the bowl off and hose the bowl and the area it covered (float, jets, and other) with carb cleaner. Pull the two jets out and clean them with carb cleaner. Put the carb in the correct orientation and turn the fuel on with new fuel in tank, fuel should pour out the carb. Push the float up and it should stop. Button it up and give it a good ride. This is the quick and easy thing I do if I get a gummed up carb. Might pull the needle out and clean it and the area it goes in. slide could use a squirt also. Others might be able to chim in on some more help. The dealers dont do a whole lot for how much you pay them. In my opinion many carb problems (gum and gunk) can be fixed with a 3 buck can of good old carb cleaner. My .02$

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Do it yourself. I was in your boat not too long ago. You'd be surprised what you can learn by reading, seeing pictures, and just tearing into stuff.

There are several threads in the FAQ to help, along with pictorials. You should be able to easily handle tearing down, cleaning the carb, jetting it, tearing down the bike, etc. You will be surprised at how simple these bikes are put together. Even installing a topend and cleaning the PV is not bad.

Suspension is the only thing that a professional tuner needs to service on a regular basis.

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Why don't you let a knowledgeable person take a quick spin on your bike? They can quickly tell you if it's running "right". The same goes with cleaning the carb. All of these things you can easily do yourself on a 2 stroke, but it would be a lot better if you could get someone with a little experience to walk you through the steps the first time.

Also, if the bike was sitting in a garage for 6 months with gas in the system, I doubt there will be any significant residue/deposits in the carb (assuming the previous owner was not using any exotic fuel or oil). Just drain the gas from the tank and the float bowl, and put in fresh premix. When you pull the float bowl plug at the bottom of the carb (it's probably got a 17mm hex head), inspect that for residue/varnish. Be careful putting it back in. Just snug it down. As a hobby I buy old bikes that have been sitting in garages and repair them for resale. In my experience it takes a lot longer than six months for any significant residue to develop.

The oil dripping from your silencer is fine. You may be a tad rich, but unless your bike is fouling a lot of plugs, I would not worry about it. Since you are a relatively new rider, as your skills increase and you run the motor harder, y0u may see that "spooge" disappear.

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Thanks guys great points. I have already drained the gas from the carb and tank and that seemed to help some. The main reason I want to take it in is when I was checking out bikes before I bought this one, I rode a 00 yz125 and it just seemed so much more responsive and pulled much much harder. I know my ktm should be able to at least match what I felt on the yz, but right now its not very close. So thats why I think it may be a jetting, carb or power vlave issue. The entire motor was rebuilt Feb of 09, so I don't think its a top end issue.

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Can I leave the carb where it is and just open the float bowl and spray carb cleaner into it and let it drain out? Can I also use compressed air will this clean it up pretty good?

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have you really taken it for a long burn yet.

do you sort of more lug it or do you scream in the top end

do it yourself all that needs to be done is change tranny oil, clean airfilter and a new sparkplug.

change the premix as this has a drastic effect on performance

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Can I leave the carb where it is and just open the float bowl and spray carb cleaner into it and let it drain out? Can I also use compressed air will this clean it up pretty good?

No, there are some very small ports in there that need blown out, including the pilot and main. Plus it will give you a chance to see how it works, make note of the needle and jets, etc. brake cleaner and comressed air will take care of it most of the time.

rpt made some good points as well.

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Ya I've had it wide open in 5th gear for 30 seconds or so. I figured that was a pretty good burn. I may find someone who knows 2t's pretty well take a spin on it and see what he says before I take it in and spend $200. I'm using Yamalube 40:1 ratio.

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The bike is really simple to work on and you can do everything in the handbook yourself. It helps to have a copy of the KTM repair manual as it shows you exactly what's what, and you can download it here http://www.freepdfmanual.com/2008/09/18/ktm-125200-motorcycle-repair-manual. If you don't have an owner's manual, then go to the KTM web site, and under your model you'll find the download section for the manual. This details what the service items are and when they should be done. In reality, top end needs checking far less often than the manual suggests provided the bike isn't heavily raced.

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if it had the top end done and it doesnt run right and the owner sold it, it may be cuz the PV isnt put together right and they sold it cuz it didnt run right. Common problem is the PV in the 125/200. So look up the threads or in the FAQ on how to check the L cyl inspection port to see if the PV is hooked up.

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Yes, I have also read about power valve "mis-assembly" on the 125. Even Jimmy Lewis, the editor of Dirt Rider, did it (and wrote about it) in the long term update on his 125 SX. If the power valve is not opening, it will really choke off the power. Again, I think your best bet is to let somebody that has experience and knows how a 125 should run take it for a spin. See if you can find another 125 rider, or at least someone with 2 stroke knowledge, to give it a try. Good luck!

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