My Road Bike tire pressure goes from 100psi to 10psi in a matter of 2 days. It stays strong for my rides but..

loses a lot of pressure afterwords. My front tire is fine. So what is the problem and what can I do to fix it?

You have a slow leak, a very common situation. Another solution is just to pump it up every other day, like you should be doing anyways.

Don't mess around with patching your tube if you decide to actually do something about the slow leak. This job is too tedious and you may or may not actually get the hole in the tube. Just replace the tube... they are NOT $10, more like $5 and you are for sure to take care of your problem.

If you've got a slow leak like that, it's easy enough to find the hole with the water trick and then patch it; but before you put everything back together, wad up a rag and wipe around the inside of the tire. Often a very tiny piece of wire (sometimes called, "Michelin wires") or other tiny piece of something, will penetrate the tire and poke a hole in the tube. If you don't find and remove the wire, etc, you'll get another flat in the new tube. Use a rag because it'll be sharp and you don't want to slice your finger. You can get a general idea of where in the tire to look by noting where the hole is on the tube.

It's also possible you have a 'spoke poke,' although those are away from the tread and they're usually bigger leaks. Spoke pokes mean you should replace the rim tape.

There is probably a small hole in your back tire to check you:
1. take off your back tire and get out the tube.
2. fill up a bucket of water and put your tube in.
3. attatch your pump to the tube and pump the tube up.
4. there should be small bubbles appearing somewhere.
5. find where the hole is.
6. buy a cheap tube reapair kit and repair the hole.

If that doesnt work then buy a tube from a bike store they cost around $10

Hope This Helps

It's either a slow leak in the tube or a bad valve.

You can test for this: Grab a shallow pan, fill it with water, and submerge the part of the wheel with the valve. If you see bubbles coming out of the valve, it's a bad valve.

If you don't see bubbles coming from the valve area, it's a slow leak in the tube somewheres.

Hope this helps.

I was in the bike shop yesterday. A replacement road tube was $3 to $5, depending on brand. It is not worth your time to futz with your existing tube and trying to repair it. Just replace it and be done.

HTH

I have experienced this many times. That is a very annoying slow leak somewhere on the tube. Change the tube.

you probably have a hole int the tire somewhere..

it might be that you face the issue of the bad valve...I suggest you to change the inner tube...

change the tube, simple as that

My suggestion is to change the frame...