We have a cottage in northern Wi. The riding is great there but because of all the deer we try to always be home before dark. Had to many close calls.

 

I agree hit them in the center you might split them in half. I hit 10 deer in my life time so far, I live in deer country and drove to work at 1 in the morning, I don't feel sorry for the deer they cost me a lot of money, one time a mother and two fawns crossed the road in front of me and the last fawn stopped in front of me and looked at me. I thought kill it now or I may hit when it got big, I didn't but I thought about it. I don't try to hit deer I missed a lot more than I hit. All the deer I hit were in car or semi.

 

I've only been riding a short time, but I've 'hit' 2 deer in cages. In both cases, the deer came out of roadside ditches on 2-lane. One from the right side in a wooded area, the other from the opposite side and across the oncoming lane. In both cases I was almost abeam the deer when I spotted them, and in both cases they 'ran into' the side of the cage around the front wheel well. It's strange looking through the windshield and seeing those glowing eyes at super close range. In both cases, the hindquarters 'spun' back and impacted the side of the vehicle, and creating as much or more damage than the initial impact point where the deer's chest hit at 90 degrees.

These 2 events make me VERY nervous about hitting a deer with a glancing blow on a bike - I'd expect the hindquarters to come around and hit at or in the vicinity of the rear wheel. I'm thinking this is a really good recipe to end up with a high-side type get-off. Because of this, until I hear a compelling reason otherwise, that if I am 'committed' to hitting one of these critters and end up having somewhat of a choice, I'm gonna try to do what Bigwillie said below.

 

I was on a sport bike a few years ago when a small buck popped out of a steep ditch/tall grass right in front of me on an otherwise quiet road. First instinct was to brake and swerve, but the deer didn't remain stationary, instead turned somewhat towards me. It was kind of a head on collision, I went down into a slide with the deer on top and smacked the back of my head on the pavement hard enough to pop the visor out of my full face and knock myself out.
I regained consciousness with no significant injuries, thanks to luck and the right gear. I don't think there was much time to choose a target...

 

I prefer to hit it from behind..

 

I hit mine dead center doing about 40 (me not the deer). It got up, looked at me like "what the hell did I do" and ran off.

 

 

Depending on speed I don't think it would matter where you hit it. Either way, your most likely going down with damage to you and the bike (to hell with the deer).
Best thing to do is avoid areas where deer are known to live and especially when they feed or are active. If your on a road trip I try to stay off the remote country roads where deer fences aren't likely.

 

That's how it most often goes down. They come out of nowhere,and the deer will determine the outcome,not the rider. Had one jump a guardrail,at dusk,when they are almost impossible to see.I was heeled over in a curve at 65 mph,no chance to do anything but brace for impact.One hell of an impact. Her last move was a jump,square into my headlight. ABS brakes kept me from losing traction,I carried her for about 50 feet on the front forks,before she kicked off and under the rear wheel,which resulted in me getting slammed,bullrider style,into the pavement,head first. When I came to,hands still on the grips.bike held up off of me by the engine guard,the deer was just coming to right next to me.She kicked me in the leg,and got up and ran off. Bike was totaled,I was unhurt. Like others,I live in an area full of wildlife,and have dodged everything from bear to moose,to wild turkey,to cattle and horses.Many times,I've had does with fawns charge me,and believe me,that will make you pinch off a section of the saddle with the old bunghole! I've shot three deer this year that had been hit and were flopping around in the road.No matter what,don't do what the guy above said,and use a knife to try and put one down,one kick can kill you.

 

I saw a video of a Harley hitting a smaller deer and the bike stayed up because he never turned his handlebars. So keep it straight at point of impact and hold on would be my guess.