How do u figure the mod is unreversible? Maybe the slotting is but the engine can returned to original position. In all honesty, if it didn't make a difference I would say so. Nothing wrong with admitting fault in buying part that didn't live up to expectations or claims. I do it with tires all the time. If I throw 150 away on hard terrain tires for one ride that aren't any count except for near concrete type dirt, so be it.