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Start problem on KTM 525!!!

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Hello everybody!

Last year I bought KTM 525 SX (2003). It was not new. From the begining, I have one problem: start the cold engine. How I start: two times move the kick from up to down with decompressor lever. Than - start. I repeat 5-6-7 times and after that - engine start. When I drive I have no problems with throttle (low or high speed). Maybe carburetor setup is not good - mixture control screw? Standard is 1,5 turns, when I checked - it was about 3 turns. Or gas level in carburetor too low?

Help me please.

P.S. Carburetor is Keihin FCR-MX 41.

Best regards from Russia!

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On my 520sx I would crack the throttle twiceand find the compression stroke and it would always fire by the 2nd kick or do the same proceedure with the choke on.

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My friends told me - do not touch the throttle when start the engine. What do I feel, when I find the compression stroke? You don't use choke on (for cold and warm engine), do you?

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Does the bike start easy when warm?

What altitude and temperature are you ridding at.? Do you know what jetting is in the carb? pilot, needle and type, and main jet.

Turn the fuel screw back to 1-1/2 to two turns out

Here's the cold start procedure: Choke off, twist throttle twice (warning: do not do this when the bike is warm) push down on the kick starter until you feel resistance then bring the kick starter back up to the start of it's stroke and kick

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When the bike is warm, during 5-7 minutes I can start it easy (kick 1 or 2 times) with a warm choke on.

I am living in Moscow, Russia. Now the air temperature is the same like in Canada - about 23-28C (75 F).

I forgot to write marks of jets, when I disassemble to clean carburetor. So I cannot tell you about it.

When I start the engine (cold), I never twist throttle. Maybe this was a problem?

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On every 4-Stroke I've ever owned (YZ426, CRF450 and now a KTM450MXC) I had to twist the throttle 2-3 times when starting the bike cold. The only time it's a big no-no to twist the throttle when starting the bike, is when the bike is warm.

Here is my starting procedure:

1. Twist throttle 3 times.

2. Pull out choke

3. Find top dead center with kick starter

4. Kick all the way through the stroke, a good full kick

If you have an electric start, I suppose you don't have to worry about finding top dead center. I've only had my 450MXC a few weeks, and the electric start fires the bike right up after I twist the throttle and pull out the choke.

This procedure typically started my bike in 1-3 kicks. Sometimes the bike would fire for a half-second and die. I would then give another 1-2 twists of the throttle and repeat.

Good Luck !!

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The answers here regarding "twisting the throttle" may be confusing. When the engine is not spinning a couple of "twists" allow the accelerator pump to squirt a little gas into the engine to help it start.

Once the engine is spinning the throttle needs to be shut or the enrichener (AKA "Choke" will not funtion.

It is also criticle that the engine idles proper when running, and valve adjustment is also criticle. The 525SX (and that model only) has aluminum retainers on the valve springs. They are shapped different, (have more meat on the top than the steel ones that most others use) and that extra meat makes valve adjustment with a feeler gauge almost impossable.

If you go to KTMTalk.com. then go the the valve adjustment section there are two articles, one that I wrote (over there my initials show up "DJH") and in that article I outline two ways, one called the "1/6th turn" method is the best way to do a 525SX

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Thank you very much to everybody who helped me!!!

What did I do on saturday:

1. Dismounted carburetor from my bike and disassembled it.

2. Cleaned all jets and "holes" inside with air

3. Assemled carburetor back

4. Setup mixture control screw

5. Twisted throttle 2-3 times

6. Kicked starter 1-2 times (not 10 minutes)

7. Thaks god! The engine alive.

When the engine warm, I pull out "warm" choke, kick the starter and no problem - I am driving again!

Thank you!

Best regards!

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