Dude , just tie it back and as long as the rest of you looks the part, clean shaven blah etc you should be ok, you're not in the Army , you don't have a Sgt Major asking if you're hair is hurting , it should cos he's standing on it blah etc.
If you look clean and tidy not like you've crawled out of a septic tank with a smell to match , your reputation will build as you get back into things. You're a civillian and it takes all sorts. Its not like youre a 25stone obese bloke trying to tell me about nutrition , fitness and diet, you're a bloke with long hair sorting someones pipework out for them
If you find its putting customers off later on then yeah go for a trim , until then save your pennies for fuel for the bike
Lis' x