Mikuni ID/help needed

[Doc]

Does anyone recognize the carb below or can anyone give some advice?? It's 32mm but...

I won it today on eBay for about $7.00 hoping it would be okay for the RM125S motor. Looks like a powerjet but I don't know enough about them  was going to blank it off if it is..snowmobile maybe?? It's from the US..can I use it if I block or remove the powerjet bits??

[DJRacing]

Doc is there a part number by the choke?

[Doc]

Deej, I haven't actually got the carb in my mitts but the guy says the model number is 500 61 B 4V 

I also picked up a super nice priced CR125M Keihin..was hoping to fit this sucker to the TS/TM125. 28mm?? I've never had much to do with these carbs..do they work CR's seem to like em' 

[DJRacing]

Keihin carbs have me stumped, I dont think I have one anywhere. I dont recognize the part number but I'm sure someone here will.

[Doc]

this is the Keihin



 paid  $15.00 for this one but I fuggered the jetting would be somewhere 'near' the ballpark 

[brent j]

The only possible help I can give Doc is-

500, the first bit of the part No is DT400B

maybe, maybe not

Brent

[Doc]

Thanks Brent, until I get the carb and look closer I'll be none the wiser I'd say. From what I've read Mikuni introduced the powerjets onto snowmobiles in the 70's. The carbs does look 70's to me with that high top. Least it was cheap 

[Lozza]

Don't you dare block that power jet off 
Looks perfect for a 125,the power jet allows a leaner needle to be run so you can have blistering top end without going blubbery on the needle.A small tweek can have that powerjet adjustable and working beautifully.The powerjet just sucks fuel dirctly from the float bowl into the airstream when the velocity is high enough.
Nothing to fear and plenty to gain.Just check the needle/seat size sleds usually have BIG sizes in there
 

[Doc]

errr..I didn't think you were allowed to run powerjets Loz..if so for sure I'll retain it but I need to consult the 'Book' first..I'll do that right now 

[Lozza]

Flatslide no, powerjet well...... (whistling while looking up)

[Doc]

Could I get clarification from someone in the know as to whether I can actually run a powerjet carb since it is infact era? The bike will be pre'78. I can't find a reference to them in 'THE BOOK' and it could be just what the S motor is begging for

[Lozza]

Pre 75 says "No Flatslides" that's about the only reference to carbs in the GCR's individual meeting supp regs might be different.A great many are probably bliisfully unaware of the neddies lurking inside that PJ.

[Doc]

Loz..I was tuned into these carbs a little with a project a friend and I built quite a few years back. T'was on an RZ500 minisprint. Fitted the powerjets (amongst other things) and he got himself a state title just like playing with a YZ125 only times 4 with everything  the pipes we made actually worked..I'll find a pic 

[Lozza]

RZ 500 already has PJ carbs but incy wincy 28mm jobbies.Lucky you were blissfully unaware of the problems with the RZ 500(and the RG500) main one being the rear bank being up to 8degrees out.

[LWC82PE]

so power jets are one of the ad on accessories you are in favour of Lozza