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Taming and tuning a kx250f

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My cousin recently bought a 2005 kx250f brand new. It's his first bike (lots of bike for him! :thumbsup: ). It's a great bike, I have an 01 yz250f and this kx rips. He is light, just like I am at only 120 lbs. The suspension I know has to break-in since it's new but we noticed that from the factory, the rebound was only 2 clicks from being full in (hard) and we also didn't have alot to play with on the compression. It's pretty harsh, so we went out on the compression (both front and rear) and went all the way in on rebound since it was rebounding way too fast but like I said, we only had 2 clicks before adjustment ended. I also set the sag up for him. It still has to break in but I know from my yz250f, putting lighter springs on it was the only way to get it right for a 120 lb person. He is sticking to the trails for now as well. We will let it break in some more and see what happens. Now for the engine. It's fully broken in. He complained of the bike being too snappy and uncontrollable out in the woods (the suspension added to the uncontrolable feeling). To see what he really meant, we swapped bikes. Wow! This kx is way more snappier than my yz, but doesn't rev out as long. My yz is not soft on the bottom, but alot smoother. I have a 50 tooth rear sprocket and an 18'' wheel. His has the stock gearing and tires. Besides adding a flywheel weight, is there anything we can do to make it not so snappy? It's snappy yet because of the stock 48 rear gearing, it stalls easily out in the woods, how can we smoooth out the bottom end response yet help it from stalling in the tight sections? Great bike, just needs some tuning for the woods and first time rider.

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Put on a quiet pipe, that really takes away the low end and throttle response. I did and I hate not having the low end power.

That might actually be a great thing to do. This bike is LOUD, seems louder than the stock pipe on my yz250f.

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u could drop a tooth or 2 on the rear

Yea, that would take away the snap but he is having a hard time using the clutch in the tight trails w/o stalling. I think he is getting the hang of the bikes power, but he is having a hard time with it stalling out. I think we are going to have to go the other way and go up 2 teeth on the rear when the chain/sprockets wear out. Also, when it does stall, it is a B*TCH getting it started. My yz250f is very easy to start after a crash or stall with the hot start.... anything we can do to help with the starting?

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check the valves on it mabey its the jetting??

use the hot start put it in neutral and find top dead center then give it 1 hard kick

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