This is an old, old trick first shown to me by my father about 45 years ago.

If you need to remove the centre stand for any reason, such as properly greasing the pivot tube, you will find that considerable strength is need to stretch the spring far enough to get it off the stand and frame. But you don't need the strength of Samson if you use this sneaky little trick.

With the bike on the centre stand, slip as many big, thickish washers as you can get between the coils of the spring, with the idea of coil-binding it. I find the big 'repair washers' perfect for this.

Take the bike off the centre stand, with some one helping by holding the bike if you have no side stand fitted. The centre stand will be flopping loose, so lift it as high as you can to get at the spring.

You should find that it will remove and replace much more easily now.