Parrafin

In the 21st century are there still people who need to clean oil and grease from their transmissions?
For goodness sake buy some dry or wax lube and put all that nonsense behind you.

I just use white spirit, its cheap and does a good job. Some of these specialist products can cost a lot.

Gunk liquid work great. Don't need very much. I do have an ultrasonic bath which does a great job of shifting all the tiny grit/ paste

I used parafin perfectly happily for many years. However, it's not terribly green - please make sure you dispose of it carefully once used, and don't just pour it down the drain / into the ground.

There are some very good alternative, dedicated products available for this job nowadays, some of which are rather greener than parafin. And actually, many of them work better/quicker in any case. Probably worth a quick chat with your local bike shop.

I have found the Muc Off degreaser aerosol very good in the past, and it looks like they do a slightly more environmentally friendly version too:
http://www.amazon.co.uk/Muc-Off-Bio-Degreaser-500-ml/dp/B001MQ01JQ

I use white spirits. seems to work well.

It will work, but will be smelly and potentially a bit firey. Choose something safer.