460 ex

[400exshop]

i have a 440 kit now. if i get a +4mm crank and pistion. do i need to get a new sleeve ( longer ) or will the one i have now be ok ?

[rubbersdown]

They make a special piston for the stroker kits that have a smaller height to them. As long as you use the piston made for a +4mm stroke the stock height deck (sleeve) will be fine.
If you choose to run a regular height piston you can add a spacer plate to the bottom of the cylinder.
Just so you know also, Correct me if im wrong guys but I believe running a +4 mil stroker in a 400ex requires some machining of the cases for clearance.

[400exshop]

What brand of crank should i go with ? H/R or what i want it to last.

[Wheelie]

+4 mil stroker causes no clearance issues. No machining required.

[78ta]

you "may" have to clearance the counterbalancer with the +4mm crank. new hot rods crank no, if you get an old version hot rods crank like me from ebay then yes. I think you have to clearance counterbalancer with a powroll crank too but may be wrong there.

I had to grind a good bit from mine to have the clearance they wanted

[Wheelie]

The Powroll crank requires no clearancing or machining of the cases.

[78ta]

wheelie, i have never used powroll stuff, but just from looking on their web site in the stroker crank installation instructions for the 400 ex they say might have to clearance the balancer. May be old info and don't have to anymore, but just wanted to make it a point that it at least needs to be checked with any stroker crank.

[78ta]

This is directly from their web site

HONDA RFVC
(400EX, XR’s, etc.)


WHEN INSTALLING A STROKER IN
HONDA RFVC ENGINES, YOU MUST
CHECK A FEW CRITICAL CLEARANCES:
THERE MUST BE A MINIMUM of .020” CLEARANCE BETWEEN:

􀂾 THE ROD AND ANY TRANSMISSION PARTS (AT THEIR CLOSEST POINT).
􀂾 THE ROD AND WINDAGE TRAY (IF ANY). RFVC’s with windage trays usually require that approximately one half the thickness be
removed in path of rod.


THERE MUST BE A MINIMUM OF .040” CLEARANCE BETWEEN:
􀂾 THE ROD AND BALANCER. In some cases, slight grinding of the balancer may be required.


􀂾 THE PISTON AND Balancer Gear AT BDC. – With shortened rod strokers, stock and many after-market pistons will require skirting to
achieve clearance. Skirt piston to 1.900” (measured from deck edge to bottom of skirt) for adequate clearance.
BE SURE the crankshaft will rotate freely before assembling the engine.


NOTE: All clearances are MINIMUMS. Whenever possible, slightly more clearance is desirable.

[Wheelie]

I've installed Powroll's stroker crank personally, and from my experience the 400ex has more than enough room to clear the crank without any grinding or clearancing.

[78ta]

sorry wheelie, i wasn't arguing with you. just saying that it is a good idea not to just throw stroker motors together, clearances should at least be check and verified.

when i put mine together, hotrods said no clearance necessary. I checked just to be safe and wasn't enough. after some research, my stroker crank was a left over early design that was repackaged in a new box with new part number. The first version needed to have counterbalancer clearanced.

[78ta]

and to answer the original posters last question,


What brand of crank should i go with ? H/R or what i want it to last.

If you have the money, do the powroll. can't beat stock honda parts for reliability. I have heard great things about their stuff.

Hotrods are good too though. Your just kinda stuck with their piston, unless you get some custom ones made.

[400exshop]

with the powerroll what pistion can you run stock or stroker ?

[78ta]

with powroll crank you can run any size or brand or compression. the catch is the piston needs to be clearanced for the crank because powroll uses a shorter rod than stock

[Wheelie]

Originally posted by 78ta
with powroll crank you can run any size or brand or compression. the catch is the piston needs to be clearanced for the crank because powroll uses a shorter rod than stock

Exactly.