03'125sx

[grunk250r]

looking for ride report/impressions of the 03'125SX....thanks!!

 

[johnpace2]

Me too!

My dealer has a few in and they are supposed to handle better and be much faster. Does anyone really believe that it will be MUCH faster? That'd be amazing.

John

 

[grunk250r]

I only have a couple little 10 minute sessions on mine now...break in stuff around a grass track...seems like it's gonna be a FUN bike!!!

 

[dstktmusa]

I just had a chance to run my friends 2003 125SX on the dyno and it was right what I expected 30-31hp. We added an FMF Gold series pipe w/Ti. silencer and was up to 33-34hp with no jetting changes. The real improvement was in the powervalve timing. We raised the pv 1/2 turn clockwise from stock and hp went to 35-36 with improvment throughout the entire rev range. A couple hundred bucks and a half turn on the pv we gained almost 6 hp without touching the carb.

 

[grunk250r]

WOW...6h.p. is some BIG gains!! Did you try the pv adjustment with the stock pipe/sil.??

 

[nj125sx]

Could someone explain how to make the powervalve adjustment. I hear people talk about it but I'm not sure what to do. Also what would be a good setting for a stock 2002. Thanks

 

[dstktmusa]

The powervalve needs to be set with the cylinderhead removed and the piston at BDC. The distance from the top of the cylinder to the bottom of the powervalve flap should be 43mm. If this is not the case then you have to remove the large 30mm (?) nut on the clutch side of the engine and the small 6mm X 1,0 screw that screws in from the bottom. Now you can turn the large screw with two flat sides on it to get the correct measurement. Clockwise would raise it up and counterclockwise lowers it. 1 full turn is 1.0mm up or down so I took the 2003 and raised the powervalve 0.5mm (1/2 turn clockwise) from stock, assuming that it was set right from the factory, it would end up being 42.5mm.

 

[Bud-Man]

dstktmusa,
When you adjust the PV, isn't it just adjusting the starting point? I didn't think it would affect the full open exhaust area. Have you had a chance to ride the bike with the new settings? I'm curious to know how much real world change there was. Also, did it affect the jetting at all?

 

[dstktmusa]

correct, you are just adjusting the starting point for the P.V. It does not make it open any further than normal, but for some reason it (the 125) likes a bigger exhaust port on the bottom (it's only 0.5mm bigger). I can't explain why the extra peak power, maybe it spins up faster from the bottom end with less "bog". He did ride it at the local motocross track and was so impressed that he did not want to mess with the jetting at all. I rode it as well and couldn't believe how fast that thing was for a 125 2t.

 

[ktmjedi]

Originally posted by dstktmusa
We added an FMF Gold series pipe w/Ti. silencer and was up to 33-34hp with no jetting changes. The real improvement was in the powervalve timing. We raised the pv 1/2 turn clockwise from stock and hp went to 35-36 with improvment throughout the entire rev range. [/B]

Which FMF pipe did you use - the SST? I have an '03 125SX and am thinking of using my 2001 DOMA Header and Pipe, however the STD pipe looks almost identical to the DOMA ....

 

[dstktmusa]

FMF Gold Series SST pipe.

 

[ktmjedi]

Tks will see how the stock combo handles,then fit the Doma tailpiece and tweak the Powervalve. Need more HP!!!!

 

[grunk250r]

Don't you need a special SST silencer to run the SST pipe??

 

[grunk250r]

Well, I called FMF and the guy said any of their silencers will work with the SST, but they have a new SST for the 03'125SX about to be released...i'm assuming the SST we've been talking about here was for an 02' right?? I hadn't even heard of ANY motor changes other than the tranny.

 

[ktmjedi]

dstktmusa mentioned using the Titanium 2 Silencer, for 2002 there is a Power Core2 and Power Core2 Shorty available. No 2003 info on the FMF site, but sure their sponsorship of KTM during 2002 must have produced some good results? My DOMA header looks identical to the stock 03 pipe. Will keep checking the website for info about new SST header for 03.

 

[Jman271]

I don't mean to butt in here and comment on your thread , however, I need to ask a few questions about the KTM 03 125 you guys are talking about. As far as getting 30-31 HP bone box stock, I saw in last years write-ups, that the 02 was getting in the mid 30's stock, am I wrong? Is this year down on HP? Also, are you saying also that w/ minor adj, that you were able to get up to 35HP w/ no motor mods? I think I need a KTM if that is the case, cuz I'm already at a loss! I have a 02 CR125 punched out till the cows come home, and it is a great bike by all means, but I probably have only 34HP w/ all that work done! What kind of gas were you running? It had to be MR2 or something HD to make that much difference. SO, if I got an 03 SX125, with all the motor mods, pipe/silncer, reeds, fuel, etc,,,this thing would be 40HP! How are these bikes as far as reliablity is concerned? Also, how is the suspension and handling? The Jap bikes I have had turn real well, but I haven't rode a KTM either. Can you guys post back? Thanks-

 

[ktmdad]

ktmjedi,

Speak with Chip @ MunnRacing about the Doma pipe for the 125sx. I believe he has access to several different Doma pipe for the 125.

 

[marcusgunby]

HP numbers can vary alot depending on the type of dyno, weather conditions, the scale used(SAE, DIN, Uncorrected, corrected etc.)so you cant really compare numbers with any accuracy other than dstktmusa got an increase of 4hp which is a good amount.The KTMs have never had any more peak than the others-they all peak at similar amounts.The KTM however has a much broader spread upto peak and thats why its such a good engine.

 

[ktm125ryder]

From those of you guys who have talked to people with the '03 125sx did they comment on the power of the low end? The only complaints I heard for last year was that the bottom end was dead. Thats where I like my power, let me know what you find out.

 

[marcusgunby]

The KTM actually makes alot of bottom end power-its just it feels less because the mid is so strong.

 

[steve125]

I haven't ridden a KTM 125, but ive heard from riders that have the bottom feels weak. Also it has a heavy flywheel feel to it compared to the jap bikes. If so maybe it's the combo of the big carby and the extra flywheel that makes the low end feel weak.????

 

[marcusgunby]

I wish our Crs had as weak a bottom end as the KTM;)

 

[steve125]

I checked out an 03 KTM 125 at the dealer the other day. Looks nice, the forks had very little stiction for not have been ridden yet. They should have speced it with black rims. It's now almost as good looking a bike as the CR. :cool:

 

[Bud-Man]

ktm125ryder,
If you want a good strong low end, look into a left over '02 125 SX. Mine has tons of roll on power. When I was riding my '01 125 SX I wished for this type of bottom end. Now I wish for my '01s top end! (So it's time to send the cylinder off to Eric Gorr for a little grinding :) .)

 

[Eddy V]

dstktmusa,
I lowered my cilinder with a 0.25mm base gasket to narrow the squish clearance and raise the compression a little.Can I still use the values you gave for adjusting the power valves?