Bikes kinda easy to kick over..

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  • bsr1st

Posted December 05, 2015 - 04:47 PM


Short story. Bought a 03 YZ450 for $400 with only carburetor gummed and gear shifter oil seal pinched, leaking oil. Has a high comp piston kit, and a nice large capacity tank from acerbis on it. Previous owner, a well friend of mine sold it to me losing interest in it said the bike had probly 10-15 hours on the high comp rebuild on the cylinder. He never rode it much after moving from California.

So, main problem is, lately the kick starting pressure on it has been going down slightly. When I first got it, damn thing would preload the shocks when hitting the comp stroke. But now, over a period of about 2-3 months, bike has reduced down to that of a 2t 250s. Its still pretty hard, makes it bounce still on the shocks from force, and wears you out if you don't get it right, but is at least noticibly lower pressured. Bike still has that terrifying power from when I first got it, and only leaks a teensy bit from procrastinating on the oil seal. But it does have one tiny bead of oil, every once in a while (every 3-6 rides) I can spot inside the vent tube going to the valve cover.

(Said power? Gave it a bit too much gas today, brought the front all the way up to the balancing point. On clay if I might add.)

Through this time of me owning it, I've been giving it attention, keeping it clean, keeping an eye on the oil and radiator fluid, oiling the chain. I've been giving it 89 octane at times out of a "oh shit I'm about to run out" situation a couple of times, but usually run 93 Oct. I do try to put octane booster in the gas when on the 89 Oct just to help it. I've also been adding about 1 cap full (probly a teaspoon, tablespoons worth) of 2t oil to the gas to help keep the insides lubed up a little. I bought a brand new sparkplug and it snapped its shroud into the head of the cylinder, so had to easy out the shroud. Thankfully another new sparkplug went in perfectly fine without resistance. (The sparkplug that snapped was defective, it was not torqued even at the correct psi, and snapped.) Last of all, replaced the hot starter plunger after the prongs had been snapped long before.

So my question to you all- What could be the reason for the easier kick start? It still gives me the same trouble it did at first, being finicky on the kicking technique (coming from a 250 2stroke. Never had a 4 stroke MX bike.)but just a little easier to kick over.

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