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YZ125 gearing

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I just picked up an 08 YZ125 recently and had it out for my first real spring ride with a fresh clutch and good traction. This is my first 125 and it scares the living Jesus out of me :jawdrop:

I went 12/48 gearing without riding it with the stock 13/48.

The thing is like a raped ape. I'm gonna switch back to stock gearing, hopefully it stretches the gear out a little and takes the light switch feel away. Like I said, I'm new to 125's but not bikes, I run a YZ250 and KTM 350SXF. It was a bit of a handful in some of the fast chopped up single track I rode today.

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You ride a yz250 and a 125 seems scarry? I can't believe this. 250 must not be running right.

EDIT: Did you mean a 250F?

Edited by rjpjnk
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You ride a yz250 and a 125 seems scarry? I can't believe this. 250 must not be running right.

EDIT: Did you mean a 250F?

No, I have a YZ250 with low to mid porting, piped, etc.

It's got a pretty smooth powerband. This little 125 hits hard and fast.

So back to stock gearing you think? I have a V3 reed block that I have yet to install, maybe that will smooth it out a little.

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Yeah, definitely try the stock gearing. So you actually feel the 250 is less scarry? Makes me want to try one.

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Yeah, definitely try the stock gearing. So you actually feel the 250 is less scarry? Makes me want to try one.

Yes, the 250 has lots of bottom and a pretty broad spread I think. The 125 goes from 10hp to 35 in a second. The 250 you can carry more speed with less throttle input. I guess I just need to get used to the way a small bore smoker delivers it's power. Definitely harder to ride faster but a load of fun. It's so light!

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Probably because you can lug the 250. You can't lug the 125 so you will really have to get good at feathering the clutch to keep it on the pipe without spinning the rear. I would work on that before changing gearing. I was thinking about gearing mine down to make first more of a crawler gear and be able to work more out of second gear on tighter, moderate hill climb stuff.

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Yes, I definitely need more seat time on the 125. I may go back to stock gearing as I never rode the bike in it's original form.

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Why did you switch to the 12 front sprocket in the first place?

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Why did you switch to the 12 front sprocket in the first place?

Tight singletrack...

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