Whats this RB barrel?

[carlos fandango]

Picked this barrel up recently, and im a bit puzzled as to what it is.

Is is unused, RB225 ports, but is 72mm bore, the spigot is 78mm and not stepped like the rb250s so very close to the stud holes




The spigot is as cast not welded or anything?
so what do you reckon?

[odd mod squad]

hello there

you will find its a very early one
if i remember correctly jb tunning used to machine and step the barrels and mod the piston
has anyone got a 250 new or old
and any feed back on their pros and cons

happy days

[eibargum]

Looking at the inlet it looks like a RB22 as the only 25s ive seen have had two fingers in the inlet to support the rings, unless like odd mod says its a early one and they changed them, if its got a number on you could ring Kempy up as they keep records .

[carlos fandango]

Well it is an early one number 27

[RobD]

If it's an early one then I believe the port timings will be for a 58mm stroke crank. I've got one the same and had the barrel top and tailed for 58mm stroke. A bored out RB22 effectively. Alternatively could machine to suit 60mm stroke as taffspeed did.