YPVS crankcase difference

[midlifecrisisrd]

Hi,

Got 3 sets of cases ( 1 set for sale on ebay ) and looked at them side by side and noticed a difference in the top case. 2 sets have an indent (about 30mm long) just above the clutch drum and the other one doesn't.

Only thing I can see it being for is clearance for the powerjet carbs where the pipe comes off the float bowl.

Can anybody confirm this and when it changed?

The set that doesn't have it are 31k-008*** so are early (84)

One that does are 29L so could be late rz250 but the other set concerns me slightly. Have said before I have a set with a number I'm not 100% if genuine, they have the number 31k-006*** so should be earlier but have the rebate so may indicate they are indeed a re stamped later set. Not an indication of them being nicked as could be some ones attempt to keep matching numbers although not for my bike. They are very well done with the machined grooves but not 100% flat and last asterix looks like it has been done with an X and a -

Steve

[Tone]

Could you post a picture of the indent you mean and I'll have a look at mine. Tone

[midlifecrisisrd]

Here it is


It seems that early 31k cases didn't have it and it was for the PJ carb clearance.

Also found that some cases have a large square hole under the sprocket but others don't. Doesn't seem to be an explanation as it is on some early and some late but not all.

Steve

[Tone]

Hi Steve
Just had a look at my 1983 LC2 Engine number 31K-006### and it Doesn't have that indent but it Does have the square hole under the neutral switch. Tone