Gen3 front Fork cap bolt size？

[AnnCris]

Hi, folks. I am planning to change front fork spring of gen3 by myself because of they are too soft for me. But I am not sure the bolt size of cap due to the fork is still on the bike and handle cover the top of fork which make it's hard to reach. I use some tools to measure it and it's pretty much close to 24mm, but I am not very sure. Does any one have accurate information about it? Thanks in advance.