Tyler Paul

The heaviest that you would want it to be depending on if your doing street, you should get from 20 to 26 pounds. Go on danscomp.com and look around the bmx bikes.
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It’s not really the weight, but it’s more likely your strength. I ride mountain bikes myself, and I have a solid steel framed Trek. It ways about 35 pounds, but I can still bunny hop (yeah, my mountain bike) about a foot off the ground. My friend has an aluminum one, I can clear 15 foot doubles on that so… Yeah start working out more… Lighter bikes are easier, so check out a MirraCo Black Pearl. My friend has one, it’s good all around, dirt jumps, park, street, trail, etc. AND IT’S LIGHT!!! Hope that helps…. LASTLY, a Black Pearl won’t break the bank either.
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For a beginner 26lbs and lighter is recommendable.
20 – 24 would be ideal (I would save the crazy light stuff for a few years down the road)
You should try to aim for quality parts though.

Say you get a 15lbs bike with plastic, aluminum, and carbon fiber. In this case the bike would be outrageously expensive, and very weak. On the other hand if you go with a 26lbs complete bike, chances are you will be working with something just as weak.

Try as hard as you can to get a bike that has:

Chromo – frame fork bars axles and cranks

Micro drive train – 25 to 9

If you buy a bike that qualifies those specifications, you should be in good shape.
References :
10 years of BMX