I have a 1999 honda 300ex and went riding with some friends and one of them has a 250ex that is stock and so is mine and we were riding down the road and I was at full throttle and the 250 flew by me and was wondering why mine is so slow and I even just got a tune up

 

What tires do both machines have? If you have bigger more aggressive tires that will slow you down.
Don't take this the wrong way but how much weight is the 250 hauling vs the 300?
I have a buddy that has the same ride as mine but he is over 100 lbs heavier than me and his machine will not haul that extra 100 lbs as fast as mine but there again we seldom ever travel over 15 mph anyway.

 

actually the person riding the 250ex weighs about 120 lbs more than me and the 250ex had the stock tires and i have razrs

 

bigger tires will make it slugish but faster on top, not slower