Help me fix a kid's bike

The chain keeps coming off my daughter's tiny Dora the Explorer bicycle every couple of days.

I can fix it, but it requires me to take off the training wheels, take off the plastic guard, wrestle with the chain for five minutes, put on the plastic guard and put on the training wheels.

Anyone know how to keep the damn thing on? I've tried pulling back the back wheel to tighten the slack, but the chain jumped right back off.

Any help would be greatly appreciated.

 

sorry, write. i'm a puss when it comes to this. mrs. petty fixes the heartbreakers' bikes.

 

Can you slide the rear tire back and tighten the chain?

 

Is the gear stripped anywhere?

 

I did, but it came right off when she started peddling. Is there a way to know how much to slide it back?

 

As long as the front wheel and handlebars are tight and the training wheels are on, she's fine.

I've been fixing my own bike since I was 11. My own skateboards, too. This is the first time I've ever had a chain not stay on. It's probably because it's a cheap bike. Most little kid bikes are.

I'll probably buy her another $75 bike before I spend $25-$50 getting this one fixed.

 

If it WON'T stay on, no matter what you do, there may be something wrong with the sprocket.

 

Now's the time on sprockets when we dance!

It almost sounds like it's bent or not in alignment. My oldest daughter's bike is a piece of crap compared to what I had when I was little. Hard as hell to adjust too.

 

Yep, I think it's bent a bit.

She wrecked it a few weeks ago at the park - the first time the chain came off - and it hasn't been the same since. We'll probably just get a new bike. I can't imagine replacing a new sprocket would be worth it.

 

The key to fixing things right is not letting her use it after you fix it. It will stay in tip-top shape if you follow this simple rule.