Dec1st

I know this may be a dumb question, but does just changing your handle bars change how your bike fits?

Ive been having problems with this bike:



It's causing me some hip and back pain. I have a hard time believing that just changing the handle bars would make a difference.

Doohickie

First thing I would do would be check the seat height. A good quick check is that when you are sitting in the seat with your leg straight out, the heal should be flat on the pedal. (When the ball of your foot is on the pedal, your leg should be just slightly bent.)

Then you can try different adjustments with the handlebars. It looks like those have quite a bit of adjustment: Up and down (by sliding the step in and out of the headset) and back and forth (by pivoting the elbow joint).

It would help if you could post a picture of you on the bike.

Retro Grouch 

Yup.

Everything on a bike works together. A handlebar change can affect the angle of your back and consequently impact low back or hip issues.

StephenH

When I first got my current bike, it would bother my back a bit when I rode it, but after a few days that was okay. Then it would bother my back a bit if I rode in the drops, but I sort of got used to that and it was okay. If I'm off the bike for two or three days or don't ride in the drops any for a while, I'll notice it when I get back on. Basically, if you're in any position that you're not normally in, it may bother you.

calamarichris

What kind of hip & back pain are you having?

Counterintuitively an upright position like that will actually put more stress on your lower back, since all of the weight of your upper body will impact your lower discs at every bump in the road.
I've had two back surgeries already and have discovered that a slightly "racier" position on bicycles and motorcycles (in which you support at least some of your upper body with your hands) is highly preferable to a straight-up-&-down position.

Consider seeing a pro bike fitter.

Machka 

Unless you replace the handlebars with something that is exactly the same shape and size ... yes, changing the handlebars will make a difference.

Greg_R

Moving any part of the bike 1cm can have a major impact in comfort. If you are new to cycling understand that certain muscles will be sore from use but there should not be any severe / sharp pain. I would bring the bike back to your local dealer and have them work with you on the fit of the bike.

This would definitely solve the problem but often these services are $$$ when compared to the price of the OP's bike.

edp773

Many good points on bike adjustment here. My first suggestion is also on seat height. I find too low a seat height is hard on my back and hips, especially on a single speed.

Velo Dog

It's impossible to tell without seeing you on the bike, but just looking at the picture, the bar seems to be very close to the saddle and awfully high. I run high-ish bars myself (level with the saddle or slightly higher), but having them so close to you could be putting more weight on your butt and back than if they were farther away. The stem looks adjustable, so you could try lowering the bars and rotating the stem so the handlebars are farther away. If that doesn't work, a new stem or new bars might.
That bike doesn't allow what we normally think of as a proper fit, but that kind of fit is based on racing and doesn't work for everybody.

XR2

No personal experience but I've heard bad things about sprung seat posts. And yes I'd try a little adjusting before buying new parts. Peter White has a good article on fitting a bicycle.

BarracksSi

Well, it's a multispeed bike according to that pic, so there's the option of using the right gear and not grinding away in too tall of a gear...

Things to consider (partly summing up other replies) --

Seat height. That suspension seatpost will change your seat height over bumps, of course -- but it also changes once you sit on it, so if you were to adjust it to a certain height by measuring it, you'd need to add a smidge to account for suspension "sag". An alternative to the straight seatpost would be a Thudbuster, which still provides suspension but doesn't change the seat-to-crank distance as much.

Saddle position front-to-back can affect your pedaling, too. If it's too far forward, the wider back of the saddle can get in the way of your legs as you pedal and mess with your hips.

Riding posture makes a difference, too. Try to ride with a more neutral body position, not bent back or forward too much.

Staying seated on bumps hurts me; I try to take the shocks with my arms and legs, not my butt.