Quads burn on tri-bike

Well, not sure BUT will say that the tri set up is meant to save the hammies for the run, thus uses the quads more.

Is this a new bike and/or setup for you? Have you not been riding much lately?

I was confused about what the LBS said to me as well. I am new at this but it's my understanding that tri-bikes are set up to spare the hammies.
Although, i haven't been riding much (freezing in NY) and this is a new bike as well.

Well, two things come to mind especially if you're going from a road bike to a tri bike:

1) Maybe the position is a bit too severe a change for you to jump right into, so you should build up time on the tri bike instead of taking a honkin' big ride right away. Rides on the trainer are more intense than on the road, given that you're constantly pedaling away, not stopped at lights, stop signs, or getting up outta the saddle to climb a hill, etc. Maybe your body is not used to this position, so is a bit "shocked" to be pushed too much too soon? The heavier use of your quads than you are used to might need a little weaning-into.

2) The LBS said your position is poor?? Well, why don't they "fix" your set up then? Do you have a good tri-bike fitter to go to??

I mean, I suppose you can expect to have a little adjustment time on the tri bike set up, but maybe the wording of your original post is making things sound more severe than they were???

Hope you can get comfy on your bike soon.

For the most part I agree with Seabiscuit. If you haven't been biking, your quads will let you know. If you are geared too high, your quads will let you know. If you are going too hard or too long, given your minimal time in the saddle, your quads will let you know. If you're positioning or fit is poor, you'll feel that in your quads too. I suggest starting out slow and building your strength and endurance, shooting for a cadence of around 90 comfortably. It'll come together quickly. Good luck!

When I made the switch from road bike to tri bike, my quads took about a month of riding to adjust. Yep, they hurt for a while, but you will adjust I'm sure. You will notice that your hammmies are much stronger the first time you do a transition run. I would also strongly suggest going to a guy who fits triathletes on their bikes.

Good luck

I went from a mountain bike to a tri bike and had been riding a lot of steep trails, the first couple of times I rode the tri bike I could barely stand afterwards... If I don't ride much, as has been the case with so much traveling lately, then my quads get sore when I ride.