Any advice for wobbly/slightly bent bicycle rims on older bicycle? I have an older RWC Female bicycle that I bought second hand a year ago and it has now in the past weeks began to feel extremely wobbly and shaky when I am riding it. It feels as if both the front and back wheels are wobbly.
I continued to ride the bicycle having a plan to take the bike into the shop to get looked at and hopefully fixed. Before I was able to do that my back tire blew out and is now completely flat.
I took the bike to the shop today and the mechanics there stated that the front rim (and maybe the back rim) is bent from bike stands etc. The ISO size of the RIM is 37-590, and the mechanic after looking at the wheel stated that this rim size is old and therefore will be very difficult to source and that they do not stock this type of wheel size.
Could you suggest if the wobbling of the wheels is due to the rim being bent (I can't see the bend with my eye as I am no expert) and whether the rim is able to be fixed with tools or if a whole new rim is required to fix the bicycle?
We are in Europe so if you know any suppliers of these size wheels that would be great too.
Thank you!
ISO 590 is indeed an older wheel rim size, also known as '650A' in the French system of wheel sizes (See this page for more details). I did some quick internet searching and found that 590 rims are available in the US at least. If you need new wheels you can have them built up, possibly using the existing hubs.
If you want to check yourself if the rims are out of true (or how bad they are) that's easy. Hold the bike off the ground, spin a wheel, watch the rim where it passes a brake pad. If the rim appears to move side to side or up and down as it passes the pad more than a few millimetres the rim is out of true.
Depending on how bad the apparent movement is the spokes may simply be adjusted, or you may need to have the wheel re-built with new spokes, or you may need new rims. What you  should do is look for a local bike repair shop that offers wheel rebuilding and have them evaluate the wheels and make a recommendation.
An additional complication is that your hub bearings may be worn out or badly adjusted. Hold the bike off the ground, grab a wheel by the rim and try to push it side to side. If you can feel the wheel moving more than just a tiny bit there is an issue with the bearings (I suspect this is contributing to the 'wobbly' feel of the bike. With old wheels there is a significant chance the bearing surfaces inside the rims are worn out which will mean you need new hubs. Chances are your bike need hubs for an obsolete rear triangle and fork width, but these are available if not common. Again, have a bike repair shop evaluate the hubs to see if they can be re-used.
Depending on what you determine about the state of the wheels you'll have to make some decisions about how much money you want to spend on new ones.