'03 YZ450F Starter shaft issue?

[maffud]

I am wondering if there is a known issue with the starter crank shaft on the '03 YZ450F. I have a friend who has two of these bikes (one for him and one for his son). His son (16 yrs old) broke the starter shaft on his bike a couple of weeks ago, and then he broke the same part on his bike yesterday. I have the same bike, too, but I have yet to have a similar problem.

It looks to me like the kick crank lever is designed to meet the side of the foot peg at the bottom of the stroke. If you kicked really hard, this contact point would act as a fulcrum and put extra bending (as opposed to rotational) stress on the shaft. Could this be the problem? Are these guys just kicking it too hard, or is this a common problem with this bike, or what?

Anyone else with the same experience or advice for avoiding this problem?

Thanks!

Dan