GSXR Carb ID Again?

[CockneyRick]

Trying to figure these carbs out. Bought as BST38's  badly altered to fit a Ford Pinto & the inlets confirm that. I then sourced enough parts to return em to std, or so i thought?

I've been told the 38's have a rubber tube powerjet which my other set have, but these have the rigid brass tube?

So what models ran the 38's & were there variants in Foreign models?

Pics i have is after i rebuilt them.

[Racer-X]

38mm were fitted to gsxr 750 L 1990 and M 1991 as standard. There are some differences to the carbs on Californian models which if my memory serves me right was pilot jet and main jet size. 

[Racer-X]

Yes the 38s do have rubber power jet tubes..... on the left side of the carbs, goes from the side of the float bowl to brass stub higher up on the carb. There is a brass tube on the right side but thats not the power tube. I have a set fitted to my 1100 k motor 7/11. 

[Racer-X]

Right side.

[CockneyRick]

Cheers for that, so that brass pipe is not the P/jet?  I really wonder what they could be then cos they are definitely 38's!

And these are the set i plan to use on the Drag bike. Bar the tubes & the general butchery the last owner did, they're pretty much the same?

Edited February 11, 2019 by CockneyRick

[Racer-X]

Yours look identical to mine.

[CockneyRick]

That was 1st set (P/jet) i bought. I then sourced a 2nd set (non P/jet) & also got some useable parts off @Captain Chaos so i could rebuild both sets.

The identical set i kept, & once completed i then sold on the 2nd set via FB to a guy (Greg Cole) in Germany/Swiss. 

I did tell him that they are definitely 38's but feel concerned as to what exactly they are? 

Both sets were hacked about to fit on Ford Pinto's which apparently is a normal thing (if you don't have a suzuki) to do!

Below are the only pics i have, now they're gone!

[Dezza]

Isn't the little brass pipe for the cold start circuit?

[Racer-X]

I've always assumed the brass tube was part of the choke system too. The 750 m 38's that I have (3 sets of) all have a large bung (17 mm spanner to undo)  on the underside of the float bowl. This is to gain access to the main jet without having to keep removing the float bowl. I think the set you've sold were off a water cooled 750 wn. They are 38 mm but don't have the large bung on the bowl. There's a set on fleabay at the moment take a look and see if they are the same as the set you sold and see what you think?. 

Edited February 11, 2019 by Racer-X

[CockneyRick]

Ooh i'll have a look. Watercooled carbs would make sense!

[Dezza]

1 hour ago, CockneyRick said:

Ooh i'll have a look. Watercooled carbs would make sense!

They would if the spacings were correct for an aircooled/oilcooled engine. Problem is they are different I have  a set of wc carbs from a wc 750 and they are about as much use as a chocolate teapot for non-wc OSS bikes. If you have accidentally become lumbered with a set then I think they are often used as an upgrade for certain car engines (allegedly) so advertise accordingly. That's what I intend on doing with mine when I can be arsed to get the bloody things to stop leaking. Racer X is right: the oilcooled 750 38mm carbs have drain bowl plugs that look similar to those on RS carbs and the like. The wc 38s don't.

[Blue]

Type in mikuni 38mm Carburetors on that we’ll known selling site, I think there’s a set on there the same 

[CockneyRick]

Well it will be interesting when the fella gets back to me, i used 2x mounting rails from the oil cooled option, so in theory they should be spaced for that purpose  

[CockneyRick]

And i did wonder why the fuel 2x T pieces  at the bottom were a bit long, so had to trim the plastic down a bit!