Carb help required...a photo to identify.

[Paul Whitehouse]

The photo you see below is one that I've taken off the internet for a set of Z1000 A1 26mm carbs and not the ones sitting on my bike as I'm writing this whilst sitting at work and have not got a photo of my actual carbs.

I started the engine on the project bike for the first time last Wednesday evening. Engine fired up ok but there was certainly a problem with number 3 carb / cyl. A quick touch of the exhausts revealed that no. 3 was not as hot as the others (it was obviously firing but possibly a fuelling issue) the carbs are fitted with all new jets (20% increase due to bellmouths / V&H sidewinder). One thing that is was very apparent is that I had 3 breather takoffs....no 3 carb has a number 1 or 4 body fitted in it's place. I blanked the extra breather position, on no.3 carb, off yesterday evening thinking that this would be the problem and that this carb was possibly taking in too much air. Started the bike this morning and still running the same...before I start to check float heights etc. would anybody know if there could possibly be another reason why a number 1 or 4 body should not be used in this position?...would there be any other airways, internally within this body, that could cause a problem?...hope this all makes sense?...any info. gratefully received. Cheers.
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[Paul Whitehouse]

Sorry...reference to the above...1 or 4 body should read 2 or 4.

[000zeds]

The carbs may be off a Z1000A2 which have a diaphram fuel tap and that vent / breather is drawing air to operate it , block the vent and it will sort it.

[Paul Whitehouse]

Hi twozeds, thanks for the reply. I'm running a Z1000 A1 fuel tap...can you elaborate as to what vent you mean?...I've blocked the one on the carb an it's made no difference. Are you saying that I need a Z1000 A2 diaphragm fuel tap?

[Pigford]

If you ain't using it for a diaphragm tap (with PRIME position) - just block it

In other words - for a simple ON/OFF/RES tap - don't need it

[Paul Whitehouse]

Ok, got it now...thanks Mr P.

[000zeds]

I forgot to mention is there 2 fuel pipe entries on the carbs as the ones that suit the diaphragm fuel tap only have 1.

Hope that helps.

[KeithZ1R]

You just needed to talk to Z1PARR he could have put you right

[zed1015]

That take off on 3 is usually the VAC for the fuel tap (same body but drilled different) but if it is a 2 or 4 then you can't run a STD 2 or 4 body in the 3 position.
It has to be 1 OR 3 .
That carb is still drawing in air from the side where the breather link pipe was connected to 1 or 3 and is causing the running problem.
It needs to be blanked off but the other side which is now connected to 4 carb is un drilled and will need opening up.

[Crofty]

exactly what rob just wrote

[Z1parR]

You just needed to talk to Z1PARR he could have put you right

[Paul Whitehouse]

Many thanks for the information chaps....I had machined a blank and fitted to the breather on carb number three last night. Still run the same. Hadn't thought of the fuel supply hole mentioned by Zed 1015...top man, many thanks mate.

I've rummaged through a box of bits that I got with the bike years ago and have found a number three carb body in a bit of a sorry state but should clean up nicely.

Cheers guys.

[FOZ1A]

Paul, chuck them in the bin and get a decent set of smoothbores, rs or cr carbs.

foz

[Paul Whitehouse]

Cheers Foz...if I win the lottery this weekend I'll do that

Didn't manage to get round to removing the carbs last night but from the explanation given by Zed1015 I did get a mirror down between carbs 2 & 3 (red line on the photo) and was hoping to see the fuel holes that Zed1015 had described....can't be 100% sure but they looks like a un-machined body to me. I trawled through various images on the net last night of 26mm Mikunis...and this is the set that looks the same as mine...a 2 fuel feed setup and this extra breather take off on carb No.3 (that the chap has looped the fuel feed pipe to) that I have blocked off but has made no difference....can anybody identify these particular carbs and tell me what model Kwak they are from?
[img][img]http://i1126.photobucket.com/albums/l610/YT1961/Mikuni_zpse5e5c294.jpg[/img][/img]

[zed1015]

The carbs with the twin fuel feeds are 1000a and can also be found on Suzuki GS's.
The extra breather on number 3 is not a breather but the vacuum take off which goes to a vacuum fuel tap.
You can tell if your 3 carb is for the vac tap as there will be a hole in the left wall of the venturi ( looking from the intake side) which is on the engine side of the slide.

Are you saying that you just presumed your carbs were a mixture of bodies because of what you thought was an extra breather on number 3 ?