Carbs

Hi, I have a kz750N1 spectre 1982 which originally would have been fitted with Keihin CV34 carbs, I’ve had it for about 8years and all this time it has been fitted with Mikuni carbs, I’ve never been able to find out what these carbs came off but they are in poor condition with some internal amateur modifications, I’ve been looking for a set of carbs for a while and have finally purchased a set off a kz1100 spectre 1982 which are Mikuni BS34, does anyone know if these will fit as in dimension wise ? I intend having them professionally stripped and cleaned and Set up for a 750 engine. Thanks

All the 650 fours through to 1100 use the same carb spacing so they should fit..
You will have to use boots for the 750 head as the bolt holes are slightly closer together or use the 1100 ones and slot the holes.

Hi, can you explain the boots to the head modification? Thanks

The holes that the boots ( inlet rubbers) bolt to on the 650/750 heads are slightly closer together by a mill or so than the 900 to 1100 heads so any 1100 boots will need their holes elongating slightly for them to fit.
You need to slot each hole equally to keep the boot central to the port.
You don't say which Mikuni carbs are currently fitted so the boots you already have may do the job.

Hi, thanks for that, I’m not sure which model the Mikuni carbs on my bike came from but they have the round Knob pull out choke ( not the sliding type) as is on the Kz1100 Mikuni carbs that I’m hopefully fitting, do you know which models shared the round pull out choke? Hopefully the carbs already on mine are off a kz1100 spectre.

Are the mikuni carbs currently on your bike BS34s off a gpz750?

Some pictures of the carbs may make it easier to identify them.

Hi, the top three pics are the unknown carbs on my bike and the bottom three are the kz1100 spectre Mikuni BS34.

The carbs on your bike look like the bs34 carbs from a gpz750. I would imagine that a set off a gpz750 ( that the PO didnt tamper with) would be better suited for your 750 than a set off a larger bike.
Those are the carburetors i am running on my 810. I haven't experimented with different carburetors on that bike, but they've been great and havnt given me any issues in the 10 or so years since i built the bike.

Cheers, I intend having them set up for a 750 engine, I was just after confirmation that they would fit before I spend on them.

What I recall the Specter where also fited with BS34 originally, the E and the L models came with Kehin's.
Brgds Anders

These look very much alike- first picture are the carbs that have been on my bike since I’ve had it and the other picture is of the Mikuni carbs off the donor bike KZ1100 spectre.