Two different fork seals part numbers?

[misterprofessionality]

When checking for replacement fork seals on the web, I found two different part numbers for a 2014 Honda cb1100. Can anybody identify the difference between these two? Why are there two?

https://www.partzilla.com/product/honda/...8da7e3342f

https://www.partzilla.com/product/honda/...8da7e3342f

[tod.branko_imp]

When checking for replacement fork seals on the web, I found two different part numbers for a 2014 Honda cb1100. Can anybody identify the difference between these two? Why are there two?

https://www.partzilla.com/product/honda/...8da7e3342f

https://www.partzilla.com/product/honda/...8da7e3342f

If you notice the part numbers are essentially the same, what is possible is that Honda changed the part number at some point and the R61 is the old designation, while D81 is new (?) And they still have a batch of seals with old designation in their stock

'14 CB1100 STD 5 speed

[misterprofessionality]

Hm. I guess that means I should get the d81.

Reccomendations for Fork oil besides the OEM reccomendation?

[pekingduck]

The 51490-MER-R61 fork seals have been superseded, meaning when supplies run out, the 51490-MKA-D81 will be used. Exact reason unknown, possibly engineering reasons, supplier availability problems, or simply cost.

With Honda, every part has a unique number that is never really changed - it is tied to a blueprint. When a part is obtained from a different supplier, or a material or design spec is changed, the part number is also changed.

Take for example a frame - if one weld is made longer/shorter or a 6mm hole needs to be 7mm, the part number (usually the last 3 numbers) is changed.

That particular fork seal 51490-MKA-D81 is used on almost all the street bikes with 41mm forks, from 300cc to 1300cc.