Currently there are no Element Bipe's that meet the weight requirements.  If you follow the thread here on RCU about the Element Bipe it is over weight with a DZ in the nose.  They are working to reduce the weight, but nothing production has come even close to making weight.  I know Insight R/C has been working on the Harmony bipe, but the prototype was also overweight.  There is one that is getting close to being ready to fly that may be under weight, but hasnt been totally finished yet. 

In the lower classes a bipe is at a serious disadvantage as the patterns are not condusive to what a bipe does well (rolling loops, rolling circules,  and snapping maneuvers).  A bipe will get blown around more in the wind and is much more work for wind correction.  They do look neat though,

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