Different 250 s

[Stoby]

In my spare parts collection I have a used 250 engine that looks identical to my 300 same size jug -head etc.I havent stripped her down yet ,but i also
have another 250 jug that is visibly smaller and i have an angled plug head that is also smaller looks like the head part # is MI 160000C might be all zeros though
Anyone know what i have?
Thanks
Stoby

 

[GMP]

The smaller cyl/angled plug head is from the original '97/'98 250 motor. The '99 and newer cyl was designed to be a 250/300 therefore larger. They are not interchangable. The 250 thats the same size is interchangable, and its an easy conversion if you desire.

 

[Stoby]

Hmmmmm?

Any Idea why someone would use this?
It came as spares with the 06 250 i bought. It was a former race bike used by an aa rider . Bike came with spare 300 jug that needs work and a completely machined ready to go smaller 250 cyl w/brand new head angle plug.
Any advantage - disadvantage ?
Thanks
Stoby

 

[GMP]

I'm talking about stock stuff. With custom machine work almost anything is possible.

 

[Stoby]

seems stock

The head is brand new untouched and the cylinder just seems to be ready to go machine wise.May be new but i think its been used before.I'm probably never gonna use this stuff (love my 300 too much and am probably selling the 250) just curious as to the difference in the 250s and why? I also have a brand new black head regular size ,is that the h.c head
thanks
Stoby

 

[noobi]

If the black head has a part number starting with MC then its the HC head from the motorcross version.