Here are some mods from ghetto to greatness for adding more tension in case you a broke bitch n got more time than money (we've all looked at that stupid doppler spring thinking meh)
The rubber hose and bolt trick:
Basically get you some 3/8th rubber hose and a bolt then jam in the the spring (be sure to cut the hose so a few mm both top n bottom stick out). I have also used rubber weather stripping wrapped many many times around a bolt for this.
The rubber hose/bolt trick WITH a kickstart spring from shitty scooter:
Same thing as above but get yourself a kickstart spring from some shitty 50cc chinese scooter n wedge it into place... this with the bolt trick works great
What you can't really tell from this picture is it hooks perfectly from the top of the spring closest to you then in the back it is on the other side of the guide
Jbots incredible contra spring mod:
This is just a great mod if you have spare shit laying around and can weld. Hell this could def be done in a janky way without welding and is super interesting.
Shock eye welded to bolt, white nylon from a revival shock, Adjustable tension. Welded Pipe guide to stop spring from moving around on frame.
Tested it today, I find that the gy6 springs I had were too stiff, And progressed much too fast to the point of being way too stiff.So I'm using a contra meant for a jog/zuma. They're a lil long, and are a bit less in diameter, with more windings per inch than the gy6 ones. So far so good.
how fucking cool is that shit!!!!!!!!