Help me ID my "xr" carb!

So let me start by introducing myself, I'm shifty00 (I would tell you my real name but I don't trust the interwebs haha)  am new to this forum. I am a welder/fabricator and I have decided to build something fun as a project. I got a Yamaha Warrior 350 for building my buddy a rack for his RZR. This thing was beat but it was free so whatever. Anyhow I went to drain the oil and found about 30lbs of magical pixy dust on the oil filter. I did manage to get it running but it was spewing smoke and didn't enjoy starting. long story short I decided it would be more fun to make a hybrid rather than dumping money into an already "Meh" engine.

That leads me too my purchase of a 1993 XR600R engine on Craigslist. I looked it over, some things are missing but all and all it looks ok, it came with a carb and at the time I was skeptical about the carb because it just looked too damn busy for an xr motor. And now after knowing what that OEM carb looks like I know this is not at all an XR carb. It has features I wouldn't mind but I have no clue what it is or if it would even work on the motor. It is a CV and a pumper and has remote choke (dose not stay engaged, feels like a spring pulls it back closed?) Anyhow can someone please tell me what the heck it is... I can't find a single damn marking on it, so I assume its some china crap but I really don't know.

here is a link the previous engine owner gave me after I txted him asking what the hell carb he gave me....

http://www.ebay.com/itm/262774188434

Also can anyone tell me if I will have oil starvation issues if it tilt the motor at a sharper angle than it would sit in the dirtbike frame? I figured dry sump would be very forgiving in that area but I worry about oil pooling to the front of the head and stuff like that. I will have about 1,000,000 questions but lets start here haha.

Here is a pic of the infant stage of the build. (engine is just resting in there no mounts made yet).

Thanks for any help with my Yamda/Honaha YFM600R...

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Your link looks like it is a mikuni of a 650l

It's not an L carb either. It looks like a Keihin CV pumper though. 

1 hour ago, JoeRC51 said:

It's not an L carb either. It looks like a Keihin CV pumper though. 

Wait a minute!  I thought carburetors were either CV or pumpers, but not both.  My understanding is that the whole point of a CV carburetor is to not need an accelerator pump.

Have I been wrong all these years?

Most carbs aren't pumpers , CV or not. There are CV pumpers , but not many. Not all flat slide carbs are pumpers either and there are flat slide CVs. 

Edited by JoeRC51

Took some closer pics, and in that last pic what is that inlet where my finger is? Is it a crank case breather smog thing? I would really love to know if this will in fact work on the XR600R, If it will work better than stock, and where I can get rebuild kits for it. and is it normal for the slide to have that much of a gap in it? do they not close all the way? Oh and it is 40mm

 

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Edited by SHIFTY00
double pic post

Mikuni BST 40. DRZ400 or a KaTooM. 

shouldn't it say Mikuni on it?

Mikuni BST 40. DRZ400 or a KaTooM. 

Not a drz 400 bsr for sure, they are 36mm.

It does look like a bsr top cap for the diaphragm though.

That ebay add is totally wrong, 87 xr600 had dual carbs. Not that thing. My stab in the dark guess is a Chinese knockoff keihin cvk 40.

Exactly on the twins.  I can't see  a large pic of it on my pc,  but it doesnt look too much like one that passed through my hands that I got when I bought a 650 l head.  

Anyone else? I would still like to know if it could work. Save me some money buying a stocker or used  FCR.

Anyone else? I would still like to know if it could work. Save me some money buying a stocker or used  FCR.

Somebody here hasn't positively identified it, there for its more than likely a chinese knock-off. Spend the money and get something that is reliable. Just my opinion, not trying to start any fires.

Yeah that is the direction I am leaning. Thanks guys for the help. I have another question... If I go FCR what darn size should I get? I see anything from like 37mm to 42mm, I saw one post where someone said 40mm is too big for the 600. Any thoughts? I would like it to have a choke though. Maybe I should just go OEM? It will be stock bore (hopefully I don't need to bore it) already ordered a Hot cam stage 1 for it and it will have a FMF pipe attached to it that was on the 350. Will also be custom air box/filter.

would still be nice to ID it so maybe I can sell it.

Edited by SHIFTY00
Yeah that is the direction I am leaning. Thanks guys for the help. I have another question... If I go FCR what darn size should I get? I see anything from like 37mm to 42mm, I saw one post where someone said 40mm is too big for the 600. Any thoughts? I would like it to have a choke though. Maybe I should just go OEM? It will be stock bore (hopefully I don't need to bore it) already ordered a Hot cam stage 1 for it and it will have a FMF pipe attached to it that was on the 350. Will also be custom air box/filter.
would still be nice to ID it so maybe I can sell it.

A 37 fcr would be the best option in my opinion. It might take a little more to get to work (and a little more money) but the preformance would be excellent.

Everybody uses the 40 or 41mm FCR on these. The TM40 Mikuni's fit to and they're less expensive. You can get a new Mikuni for the price of a beat FCR. The FCR is expensive because of the popularity of used take off carbs. The Mikuni is comparable and simpler to set up. Anything smaller is too small for the intake manifold. The carb you've got should work , the only problem MAY be figuring out what jets to use in it , but you should be able to figure that out by the physical dimensions and the threads on the jets you've got.

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