Kinda stumped on what bike to get...

Ok, I'm new here. And was wondering what bike would be good for me.

I'm 5' 0" and 85 lbs, I'm not too agressive, and I'm pretty cautious... I've grown out of my DRZ110 and was thinking about getting into motocross for fun, not races or anything, but something that can handle jumps and goes faster than 45mph. I was thinking about getting a Yamaha YZ85, but I'm not sure if I want a 2 stroke. And I have some questions about them.

1. Do you use the clutch when you shift? Or just on accellerating and exiting turns?

2. How often would I have to replace the top end if I ride like once a week or less at the track? I might take it out for like 15 minutes at my house, but there's not really any place to ride, so is this considered easy on it?

3. How much does it cost to do a top end job? My mom freaks out about money issues...Could my friend and I do it?

4. I have kinda weak hands and was wondering if the clutch would be too hard for me to pull.

We are going to the dealer tomorrow afternoon, so I would appreciate fast replies.

Thanks!!!

How would I know when the top end needs to be replaced? What are the procedures to replace it? And I usually don't ride too hard.

Well, thanks for all the advice! I went with the TTR 125L because it was cheaper, same size and required little maintenence. I'm not a truely agressive rider and don't usually jump anything big, But it seams to have a lot of cround clearance, so I'm happy. I have no problem with the clutch, I stalled it once when taking off, but that's it. The only problem I have is finding neutral, I seem to pull too far up when in first and then it pops into second and stalls and dies... But I've only had it for like 5 hours, so I'm sure I'll get used to it.

Thanks again guys!