Intake O-Ring Fitment?

[OOO]

Should an intake o-ring easily fit into the grove on the intake or should it need to be stretched to fit?

I am replacing the intakes and the o-rings on my 1981 GS450T. The intake o-ring that I purchased is slightly smaller than the grove on the new intake. I can stretch it slightly and make it fit. Is this normal or was i shipped the wrong sized o-ring? I've included a picture and I would appreciate any feedback. Thanks!

 

[GSCafe]

I'm gonna say stretch it. Mine required slight persuasion to fall into the groove.

 

[Big T]

Wrong size

 

[JJ]

Definitely the wrong size.

 

[GSCafe]

Wow, I'm wrong according to others. I defer.

 

[tkent02]

Mine dropped right in on my 450, fit perfectly. Can't remember the size, but it was a metric size Viton oring from the local O ring oracle.

Looks like yours is about 2mm too small on the ID.

Measure the inside diameter, and the thickness, get one slightly thicker than the groove is deep, and one in which the inside diameter matches the inside of that slot.
Get Viton and it will last forever.

 

[GSCafe]

My o rings came in OEM packaging. Perhaps o rings shrink a little over time if it has been on the shelf awhile?

 

[robertbarr]

I'm really glad you didn't get that from me... it should be a 40mm inside diameter, and no, it shouldn't shrink over time. That O-ring is almost certainly a 38mm. What was the part number on the OEM package?

 

[OOO]

I've contacted the vendor and they are shipping the proper sized o-rings. Thank you all for the assistance and confirmation.