A stupid question was brought up to me and I find that I can't point anywhere and say 'there's the answer.' The question is thus: can bikers charge 12" in the assault phase?
I think to myself; 'what a silly question, only beasts and cavalry charge 12".'
So I check the rulebook. Says they can move 12" in the movement phase (if they don't turbo-boost). Peachy. I'm good with that. However the assault section says that "All of the models in an assaulting unit make their assault move following the same rules as in the Movement phase..." The bikes entry clarifies nothing for assault except counting difficult terrain as dangerous.
So I've got something saying that bikes charge 12" and nothing to contradict it. Bikes have assaulted 6" since I've been playing but the 5e rulebook is telling us otherwise.

I thought I may have a point with their entry saying they can move 12" in the movement phase but the standard rules for moving in the movement section also specify the movement phase. And the assault rules say they move as in the movement phase anyway. Is this a hugely overlooked boost to bikes?

hmm, good question...
Ill see what i can find!

On page 33 of the 5th edition rulebook, under declare assualt it says "... maximum distance most units can move during an assault is 6"". It doesn't say all units move 6" unless stated elsewhere as I thought I remembered it.

And the rule you pointed out about following the same rules as in the movement phase (p34) is one I hadn't really noticed.

I do believe the you are right, as written bikes may charge 12" as nothing in their rules contradicts this. The only entries where they elaborate are the ones where the two distances are different. This omission would lead one to believe that the new rules are written to give this boon to bikes.

I guess I'll have to get more bikes.

The fact that other 12" moving units, like Jump Infantry have their assault rules specifically state that they can only assault 6" further boosts this theory. I broke out the BRB hoping to disprove this silly notion, but I can't find a way to. The FAQ/Errata doesn't clarify things either.

I may just have to buy some bikes too....

All I could find to disprove this is the eldar jetbike rule. Is states that the bikes are allowed the 6in's of movement in the assault phase even if they don't assault. By useing that rule you can conclude that it is only 6in's. Also it doesn't state that the movement is move like movement in the movement phase in the bike type section of the book, since it dosen't list 12in directly I don't think you can move that far.

Well, firstly if anyone tries this, smack them in the head with the rule book a few times - physical violence is the best way to ensure fair gameplay

Then point them to the bike movement rules which say that bikes move 12 inch "in the movement phase"...and only in the movement phase. Otherwise, they follow the same rules for infantry, which have a 6" move and assault.

Now, you may say "but it says follow the same rules as in the movement phase", but thats bollocks. you're following the same rules as infantry have in the movement phase, as bikes can use their 12" move only in the movement phase, not in the assault phase. In the assault phase, they're still normal infantry.

Its a tricky thing if you're going to pick it apart raw wise, but still, smacking people in the head with a rule book when they they try to pull this sort of thing really helps solve a number of problems.

Thing is that regular infantry movement is also explicitly stated as "in the movement phase" with the same wording as the bikers in the biker entry.

Honestly, it kinda makes sense too. Jump infantry zoom forward on jetpacks and then charge on foot but a biker doesn't get off his bike and push it into assault.

maddermax is all over it. Bikes only assault 6 inches.

I like to smack people in the head with the BRB.... Alot.....

It is interesting that opponents of this notion can only offer violence as their response. Kind of shows the weakness of their stance.

p51, near the top
This means unless it says specifically in the unit type entry, the models of this type behave exactly as infantry under a given set of circumstances.

Infantry charge 6"
Unless the rules explicitly state otherwise (such as with cavalry), all other units charge 6"

Nothing in the entry for bikes (or jump packs, or jetbikes for that matter) says that they may move 12" in the assault phase.

The jokes about violence aren't a sign of a weak argument, just an expression of annoyance at people who try to get around the rules.

I;ve got a rule that says they charge like infantry. Have you got a rule that says they don't?