Nice one, I was just wondering as my current Hyper 7 is my first buggy and I only started getting advice on engines after I had run a good few tanks through it, currently it runs fine but it does not respond to tweaking (HSN, LSN) as it should, my mate also has one (not Phil) that acts almost opposite to mine, After reading through the Ultimate Nitro Engine guide and also based on the general concensus of opinion on here I would say we have got two of the much talked about dodgy Hyper 21 carbs. This being the case I have ordered a OS 20E carb and was wondering if I could rebreak my engine in if it is necessary at some point in the future, as I dotn want to spend £50 on a carb to put on a worn or damaged engine........

EDIT: BTW is the OS 20E a slide carb or rotary?, same as for the stock hyper 21 is that slide or rotary?