Author Topic: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?  (Read 3247 times)

0 Members and 1 Guest are viewing this topic.

Offline Ausmithe

  • Full Member
  • *
  • Posts: 55
I'd like to replace the o-rings in my intake manifolds, as well as on all tappet covers, which use the same o-rings. The part number is 91302-001-020    O-RING (30.8MM) . So they end up being about $2.50 each and I was hoping to order through a place like OringUSA.com where they sell stuff for closer to .20 each. Problem is I don't know the thickness of the o-ring, just the diameter.

If I definitely need to go OEM on these I guess I'll bite the bullet and do so, but geesh it's tough to spend over $30 on 12 o-rings that should really only cost about $3 total. So if anyone knows the correct thickness or can recommend a cheaper source than just going OEM, I'm listening.

Thanks.

1974 CB750
1972 CB500

Offline mono

  • Definitely no
  • Expert
  • ****
  • Posts: 1,271
  • 1975 Honda CB550, 1978 CB750K (in progress)
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #1 on: September 11, 2012, 10:23:18 AM »
on my 550 (should be the same) i was able to replace them with nitrile o-rings from a Harbor Freight o-ring kit that i bought for about 3 bucks, work just fine.

found a link:   it's $6 (mine must have been on sale)
http://www.harborfreight.com/397-piece-metric-o-ring-assortment-67580.html

Offline Ausmithe

  • Full Member
  • *
  • Posts: 55
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #2 on: September 11, 2012, 10:32:57 AM »
Excellent. Does this kit contain enough of that size to do all eight tappet covers and the four intakes ?
1974 CB750
1972 CB500

Offline mono

  • Definitely no
  • Expert
  • ****
  • Posts: 1,271
  • 1975 Honda CB550, 1978 CB750K (in progress)
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #3 on: September 11, 2012, 11:46:10 AM »
oh yeah - i think there's 12 of them.  that size o-ring fits somewhere else too on the 500/550.  can't remember what right now, but there's plenty of rings to go round.  they also have enough of another size in there to replace all the o-rings in your carb lines.

it's really an amazingly good kit for $6.  :)

Offline Ausmithe

  • Full Member
  • *
  • Posts: 55
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #4 on: September 11, 2012, 12:59:23 PM »
Thanks Mono..great tip!
1974 CB750
1972 CB500

Offline mono

  • Definitely no
  • Expert
  • ****
  • Posts: 1,271
  • 1975 Honda CB550, 1978 CB750K (in progress)
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #5 on: September 11, 2012, 01:03:46 PM »
my pleasure!

PS - if you're visiting/ordering from H.F., snag a set  of their airbrush cleaning brushes.  they worked great for cleaning out the little passages in my carbs, and even inside the jets.    :)

Offline dave500

  • Really Old Timer ...
  • *******
  • Posts: 16,996
  • WHAT?no gravy?
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #6 on: September 11, 2012, 01:17:49 PM »
the inlet manifold and the tappet cover o ring are the same,i get away with 30x3.5

Offline brewsky

  • Expert
  • ****
  • Posts: 1,110
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #7 on: September 11, 2012, 04:26:23 PM »
I used AS568-217 (1 3/16 ID 1/8 thick) for the tappet covers
And AS568-218 (1 1/4 ID 1/8 thick) for the manifolds

I think 30 or 31 x 3.5 metric would work fine.
66 CA77
78 550K
78 CB750K
02 FZ1
09 GL 1800

Offline Dinola

  • Full Member
  • *
  • Posts: 29
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #8 on: September 11, 2012, 09:02:41 PM »
I'm lurking on this convo.. thanks for the info.

Offline That 70s Bike

  • Honey I'm not obsessed, see... I'm just an
  • Enthusiast
  • **
  • Posts: 185
  • SEE YOUR AD HERE!
Re: Anyone know the MM thickness of the Tappet Cover O-Rings for a 500?
« Reply #9 on: September 11, 2012, 10:28:56 PM »
Yep, I bought similiar kit from Bennett Auto Parts for $9 or $11 :(
I think T.A.S. online or ebaY sold the tappet ones for around this price also.
CB750K6- survivor   CB500K2, CB550K2- projects