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KTM 380 and 300

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Im going to build a supermoto and was looking at the KTM 300 and 380, I would like peoples opinions on the different models, I am currently leaning towed the 380. Also I am looking at a few 380’s one a 1999 and one a 2002, I was wondering what the differences were between the years.
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If you're buying in the same year bracket you may as well get the 380 over the 300. The 2002 model will have USD forks compared to the 50mm RSU on the 1999. Only real big issue with the 380 in my mind is the bottom end costs a ton to rebuild if you ever have to have it done.

Other than that you can swap over newer forks, shocks, clutch, plastics, etc etc from different models and get a relatively nice more modern looking bike. If you have the money that is.
380s and older 300s are notoriously picky when it comes to jetting, and this is even worse when you try to street ride them. After a lot of tinkering, I have a pretty decent jetting setup for put-putting on my 01 300. It's still far from perfect, however.
They're fine as long as you get the head modded. With the JD needles and a head mod my 380 had incredibly smooth throttle response and low throttle opening composure.
Well, I must have some work to do yet on mine then. I've got the JD kit installed and my head has been cut and my "low throttle opening composure" isn't the best. Throttle response is fine when you get it cracked open and want to haul the mail.
Have you tested alternate slides? Steady state cruise is usually around the 1/4 throttle area and a slide change has the most effect here. This is assuming you're tried needles with alternate straight diameters and can't find one to work.
I have tried the 6.5 and 7 slides. As far as needles, the bike came with a NOZH and I have also played with both the JD red and blue. I currently have JD blue in notch 2 (one leaner than middle).
What about a real clean low hours 2002 300 vs. a 2007 300 for a little bit more money, or a 2004 thats cheaper.
How much is a little bit? Older bikes that haven't been run much will have a different subset of problems than a newer bike. Junked up carbs, dried out crank seals, etc. The newer bike will probably have more favorable suspension and I think the 2007 will be easier to get jetted correctly.
I have tried the 6.5 and 7 slides. As far as needles, the bike came with a NOZH and I have also played with both the JD red and blue. I currently have JD blue in notch 2 (one leaner than middle).
Is it acting rich or lean?
I am getting some pretty good pipe bang once it gets warmed up (I wouldn't touch the jetting if it ran as great warmed up as it does when it's cold), which I believe is a rich condition. Otherwise, I occasionally get what I think is a ping or two at one particular throttle opening. I'm getting a moderate amount of spooge, and a little bit of smoke on the needle before it's warmed up.

170 main
48 pilot
JD blue clip 2
2ish turns on the air screw
Pro Circuit works pipe
stock silencer with unknown condition packing (probably needs to be repacked, plan on it this weekend)
unknown hours on the top end (need to check compression)
MikeS head mod
91 octane pump gas
Motul 710 @ 40:1

To the OP...sorry for the derail. I will make my own thread in the KTM Forum if you'd like...
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Honestly, if you're happy with the jetting when the bike is warm I'd almost except that as finished. But to tweak more I'd probably make sure some of the other variables were taken out. Things like top end condition, x/z piston setup, reed condition and float level. A reed that's not sealing will act rich in this area...but it won't change condition once the engine is warm.

From there if you think it's rich at 1/5-1/4 throttle you could try the red needle. It's been a while but I think the only difference was a larger diameter on the straight section of the needle which will lean your 1/8-1/4 area. If I'm wrong it changes other things then I'd look on ktmtalk and find the equivalent of the JD blue needle in Keihin code. Then find a needle with 1 step larger diameter to test.

That's where I'd go anyway =]
How do you guys make out actualy riding these things on the street? Like can you keep a steady throttle opening and cruise or do you always have to be on/off? (my experience with 2 strokes are 125/250 mx bikes...) Thanks
Even with mine not jetted 100%, it's very doable on the street. I drive it 5 miles one way to work whenever the weather allows (30-50mph side streets). Mine doesn't like to cruise at 30 but does fine at 40-50. I can also hop on freeways and do 70ish for short periods without feeling like I'm going to blow the thing up.
Get a 380. They pull street gearing a ton better. Im about to embark on the jetting nightmare on mine.

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Sick. I dig the newer bodywork.
i would recommend a 380 if available

i ride a 380 SM on the street since 1999 and on the track since 2000 and IMO its absolutely durable on the street (if you dont mishandle it) and on the track its powerfull enough to compete (top 10 rank in last years swiss supermoto championship)
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