I'm on strike 2 here but thankfully this isn't baseball. The reasoning and my history. If you haven't figured it out yet I've done a crap load of work on these motors over the last 7 years but they have had 4 wheels around them. In the EX world there are a lot of carburetor options and although many are great there's a cheap alternative that runs 95% as hard as the high dollar options, some even liking it better then aftermarket. When I joined up here in the 2 wheel club I was shocked that the only accepted option was $400 for a 36mm Mikuni Pumper that isn't any bigger then stock! That cheap alternative for the EX is an 04-05 trx450r carb. It's 42mm round slide Kiehin piston-valve with accelerator pump and a mildly modded 400 loves it with a surprisingly strong bottom end yet. Yes I said 42mm! So as I build my XR4 I already know that I'd be shooting myself in the foot if I settled on a 36mm carb because I like bigger bores and cams and this motor likes bigger carbs. Makes sense, it is 400cc. Don't get me wrong though, the Mikuni is a real nice pumper for a stock bike and would seem fine on a well modded machine too but this 4 stroke is like every other one in the world in regards to when you go big inside, you want to go bigger outside or you're missing out. Whether the info is appreciated or scoffed at I'll post up my findings one by one as I try to find viable alternatives. When I say viable I mean still being able to use the stock environment and not needing a ton of work. I'm sure collectively this is not a new idea to search for such a beast but I enjoy a good project and I like cheap alternatives when they produce results. Currently the "test bike" is a 2000 Xr400r, snorkel removed, Uni filter, stock engine, stock headpipe and a 4" supertrapp slip-on with 11 discs.