Crank oil seal - new style vs old?

[Tim of DO THE TON]

So I'm putting my engine together, and am putting the oil seals in.

Some background - I built a 750 rephased motor last winter, and ordered the seal kit from MikesXS. Based on recommendations from members, I ordered all the seals OEM from Yamaha as it was suggested they would be better quality.

From what I remember, I used a combination of the two sets. So I have many of the Yamaha OEM seals here to use on the engine I'm doing now.

Anyhow - bottom line is I needed to order the crank seal - behind the rotor.

Original part is labelled SD 25 40 9-L-1 It is 9mm thick and has a lip that mates with a groove on the engine cases. Part 93102-25121

Well this seems to have been superceded by a new part number, 93102-25061. This is a non-lipped 8mm thick seal. SD 25 40 8.

Any thoughts? Clearly it fits, given the same OD and ID dimensions, but there is no lip on the seal to mate with the cases and it's 1mm thinner.

 

[hard_y_rd]

There's no lip at all? I noticed a difference in the 40 year old seal in my engine compared to the new one. I think it's for an easier install without splitting the cases.

 

[Tim of DO THE TON]

No lip at all. I'm working on getting the 'old' style with the lip. Unfortunately XS650Direct.com is moving and can't ship anything for another week. They specifically describe the seal I want. Was hoping to put the bottom end together this week and top end on this weekend but it might have to wait.

 

[hard_y_rd]

Here's a pic of the old vs the new one from XS650direct. It sucks waiting for a small part. Especially if they don't have it in stock.

 

[Tim of DO THE TON]

Yeah the new one from Yamaha has a plain edge. What are the numbers on the seal from XS650Direct if you don't mind?

 

[hard_y_rd]

I believe it's SD 25-40-9

 

[brat]

Hey Tim,

What was the verdict? Did you figure out if the XS650direct had the original lip or modified version? Did you split the case to install this?