Locktight comes on many threaded areas - crank bolts, bb shells, stem bolts, hub bolts - so I doubt its likely to void any warrenties. And 'open bearing' style hubs are not a good idea for trials. The Onza, Monty and Trialtech open bearing hubs are all 'bad' when compared with sealed hubs that just cost around £20 more. The sealed hubs will outlast the cheaper open bearing hubs. My advise is to fork out that extra bit of cash and buy something along the lines of the Onza T-master or Trialtech Sport hubs - allthough a lot of riders tend to snap these 10mm axles (after a fair amount of time riding ofcourse), the bearings won't come loose all the time so the life of the hub will be increased alot. EDIT: If you can afford it defenatly get an Echo fixed hub - the axles on these are a lot stronger. There have been two different models over the years - one with a 12mm axle and one with a 17mm axle (both are machined down to 10mm to fit the dropouts), and these hubs are solid! I've had both and not a single problem on either. they are worth the £70 if you've got that money to spend