O-rings for 1981 GS400L

[sk88er44]

Hey guys,

I was looking through the pages here and found that website to order the O-ring set for my carb. I emailed the company asking for the kit for my bike and this was the reply:

"I can't find that bike in any exploded diagram -- Canadian imported bike -- so you'll have to determine if your carbs are similar to the 450's of that year, or the CV's that came on the inline 4's. I carry both kits, but you have to figure out which you need."

Any idea what I should tell him?

Thanks in advance

[BassCliff]

Hi,

Your bike uses the Mikuni BS34SS carbs (CV type), just like the GS450.


Thank you for your indulgence,

BassCliff

[robertbarr]

OK, time for pictures.

I can't add the photo from my Pbase, but I can leave links, so here's a U.S. 450 carb of that era (you said '81)

And here's another.

See the bottom there, on the first photo, the brass-looking thing in the very center? Emulsion tube, I think they're called. That's an interference fit on the US 450's. On later 450's the carbs are pretty much identical to the inline 4's of this era. That's the difference. They are entirely different carbs with different O-ring kits. 0% interchangeable.

If you want more detail, just click 'Original' in the lower right of the Pbase page. The English muffins aren't included -- they're my breakfast.

[robertbarr]

And maybe a better angle, here:

[BassCliff]

Hi,

Your bike uses the Mikuni BS34SS carbs (CV type), just like the GS450.

Sorry, perhaps I spoke too quickly. I suppose you shouldn't believe everything you read on the internet.



Thank you for your indulgence,

BassCliff

[robertbarr]

Hi,



Sorry, perhaps I spoke too quickly. I suppose you shouldn't believe everything you read on the internet.



Thank you for your indulgence,

BassCliff

You still might be correct; his carbs might be the same as those used on the '79 thru '82 U.S. 450's. But they could also be the 'regular' CV's that are covered in the cleanup series and elsewhere. There's no way I know of for us to check, since we don't have his carbs in hand.

The owner does, though, so now he has what he needs to check & make sure.

[sk88er44]

hmmm I guess I'll have to check it out and get back to you guys, thanks

[Gorminrider]

It's very difficult alright. There are slight differences looking at the parts fiches. Canadian/Euro 400's (8 valve, square cam covers) have a pull-knob to choke...the 450's (4 valve round cam covers) have a lever. Idle mix also appears in a different locale.The carb bodies themselves are not identical.... and the fiche numbers for bits seldom match....

The GS550EX carbs look to be a better match as to fiche numbers-just the first four I looked at as a guess....but don't trust me- I have the Fiches from BassCliff- you could too! ...
Me, I just go to my local mechanic here and he scores 100% for the few bits I buy.

added: you could possibly send the on-line supplier the screen-grabbed pages (include the parts number page) from the fiche that matches with a note per the Canadian VS US models conundrum...