I have a Gaint QSR City which I am trying to fix for my mother.
The BB is a single ring made by / called ProWheel.
It's not on my radar as I am used to mtn bike BB's but as it's very loose & I was wondering if there is a simple tightening fix I can do with limited tools.
I believe that you are reefing to the crank arms. If that is the case I suspect that the bolts that hold the cranks to the BB are a little loose. Simple fix, remove the cap from the center of the crank and tighten the bolt.
If not the case please send a picture so we can assist.
Trouble is, once a crank has started to wiggle on the bb axle it quickly destroys the rather critical fit. You can try to up the torque, but don't be surprised if you end up having to replace the cranks.
Yes, that sound about right. I called the bike shop but of course they said to bring it in and since they set up the bike and it's done maybe 10 miles in 4 years, I am not well disposed to letting them have a go at it!
I'll have a look at getting the end caps off and if I do not succeed (it's not my home and I do not have my tools to hand) I will post up some images.