Guys, I've been riding my cube reaction with the bosch performance cx now for a month and only covered 140 miles but I have a few teething problems. Under my own power I'm spinning out at like 25mph cruising which is very annoying so I'm looking to put on a 19 or 20 tooth front sprocket in place of my 15. Has anyone who has done this any info on their top speed from doing this? Also as I'm putting on a bigger sprocket can anyone recommend a decent chain that won't cost a bomb? (guessing I need a bigger chain) And has it made much difference on hill climbs? I have also ordered a bad ass box aswell for hooning about with on trails as I cant keep up with my super fit mate anymore with my bad knees. I also have a creak in my crank already which is driving me nuts as it's all tight! All advice welcome.