Topic: Update: Found source for o-rings for Service Bulletin #42 for early CB750

[markb]

I'm looking for a source for a gasket set for early CB750s that includes the modified head gasket with larger holes and the set of 8 o-rings per Honda service bulletin #42.  (This is not the later packing and knock pin version).  Last time I had to buy the gasket and orings separately.  I already tried Vesrah and they don't have it.  Other suppliers haven't got back to me yet.  Anyone know?
Thanks,
Mark

[markb]

Haven't had much luck and now I found out the o-rings (12115-300-305) are not available anymore although the gasket is.  Anyone have a source for the o-rings or have a description.  That part number was for a pack of 8.  There must be a number for the o-ring itself.  BTW, it has a square cross section if that helps.  I did this along with APE studs on my last rebuild and so far I have no leaks so I'd like to do the same again.

[paddy paul]

Try bike bandit, also a while back in a post someone listed a majority of OEM dealers and there sites, most of them have a part # locator ,I don't know about where you live ,but here in colorado we have a place called Rocket Seal, and they have or can get any type,size of oaring you could need, with no minimum's, you might be able to get what you need through them or try CAT, Komatsu, john Deere, all of them use Metric o-rings, you just have to be a little resourcefull....

[markb]

I tried almost a dozen different dealers with no luck but I will try Bike Bandit.  Rocket Seal looks like a good possiblity.  I actually found a guy on ebay that had four of them so I grabbed them.  I can send one out and hopefully get an exact match.  BTW it looks like the newer kits have the head gasket with the larger holes but they're still available separately too.  Thanks for the comeback.
Mark

[hijynx]

you may be able to match something up here http://www.mcmaster.com/#square-o-rings/=559jg3 if not they say they will find what you need

[markb]

Thanks for the suggestion.  Unfortunately the Buna-N/Nitrile are too low temp.  They need to be Viton

[Kevin D]

I tried to find the p/n's in the service bulletin and was also unsuccessful. I ended up improvising and got my viton quad rings here, although it looks like they might be out of stock at the moment. I believe I used the -014's:

http://www.smallparts.com/

[markb]

Thanks, I'll check them out too.

[markb]

An update on the o-rings.  I got the four from the guy on ebay.  Near as I can measure they are 14mm ID (17mm OD) and 1.5mm thick.  I'm going to order some that size and see how they compare.

[HedNut]

I'm not sure about your scenario...but Cycle Exchange has a good looking "complete" gasket set.
I haven't installed it yet...but went through it and everything is there ....although it's for my K8.

[markb]

The problem isn't finding a "complete" set.  The sets are technically complete and include a head gasket.  The problem is that everything before serial number 2352932 (K4-K5) was recommended by Honda (in 1975) to use an additional o-ring to help prevent oil leaks.  They were never included on the originals.  Everything after that had a different cylinder and seals to (help) solve the problem. 

[HedNut]

Oh I see.... very good to know.   Man I love this forum! So informative! Thanks for that...
On that note I'm truely sorry I couldn't help...    But it sounds like you're on the right track... I had a problem with my KTM dirty bike.... actually the problem was that I was a cheap ass and didn't want to spend $30 on an exhaust O-ring.    So I went to a local Bearings supplier...gave them the size (which was very odd) and material I wanted and in a week I had a bag of 10 (min. order) for $15....so if anybody needs an 03' KTM 125 SX exhaust o-ring or two....lol

Cheers and good luck!

[markb]

I found a source for the set of 8 o-rings Honda part #12115-300-305!  Western Hills Honda, 513-662-7759.  Ask for Terry in the vintage parts department.  They had about 50 sets in stock.  I bought a couple while I was at it.  He was extremely helpful with some other hard to find bits too.  Highly recommend this seller.
Mark