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Would A Big Bore Kit Make A Bike Harder To Start?

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The first time I replaced the piston in my 05 KX250F I discovered it was a 81mm over bore.(276cc) :ride:

My question though is, do over bore's make a bike harder to start? Because mine can be a real PITA to start. :thumbsup:

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Well yes an no I guess. If it's jetted wrong then yes.

Along with if this is your first fourstroke then you probably didn't have thenproper starting technique.

If you over kick and disengauge the auto decompression then itl be even harder then a STD bore as you have to compress that much more volume.

So back to yes and no. Depend on your technique and or how fed your jetting is.

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Yeah it's my first four stroke and yes I've never had the jetting spot on. Guess I'll try and get the jetting setup right and also work on my technique.

But basically what you’re saying when the jetting IS right it shouldn't start any harder?

Thanks :thumbsup:

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Nope. My guess is your starting technique is that of a two stroke.

These bike require solid slow dileberate kicks.

I can start my bike with my hand. Best way is bassicly is to stand on the kickstart and let your weight do the work.

If you spool the cams fast it disengauges the auto decomp and the. You have a hella time starting it. That and short kicks don't rotate it enough to get full turns to fire.

People who are used to two stroke starting take a while to learn how to start fourstrokes.

Also two stroke ppl also like to twist the throttle. This is a huge no no with tuumpers.

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:thumbsup: Damn your good. :lol: Yeah I'd say it's more my technique then anything else.

I tried to give you some Rep but I got this "You must spread some Reputation around before giving it to Pr1malR8gw again.":lame::ride:

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I have the Athena 290 kit and it starts first kick every time.

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I have the Athena 290 kit and it starts first kick every time.

Yeah it must be my technique. :lol:

Welcome to TT :ride:

and Team :thumbsup:

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