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Discussion Starter · #1 · (Edited)
Are these carbs PW-22s or PW-20s? I measure exactly 22mm height in the intake (head side) bore at the slide bore, and 18mm width at the same point. The rear facing power jet is numbered 160 and the side facing power jet (behind the threaded aluminum plug) is numbered 140. the main jet is numbered 90, and the pilot jet is numbered 38. The first photo shows a partially crushed section of that long brass tube and I'm wondering what effect, if any, it might have with feeding the power jet circuit, and whether or not I should try to 'repair' it.

I did not want to start a new thread about my carb questions but I had a most frustrating 90 minute session when I tried to put all this in my previous thread. I keep getting dropped and was instructed required to log in again, and again. When I did I found that what you see here had disappeared. Any advice to help smooth the process would be greatly appreciated.
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They look like they're from a sloper cl175 so they're 22's does the other one still have the choke butterfly if so what number is printed on it?
The tube runs up to the " power jet" and is effectively a float bowl vent so as long as it is clear the dent shouldn't matter. For all it's worth the latter models got rid of thepower jet altogether so they probably didn't work as intended
 

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Discussion Starter · #3 ·
Thanks Simo. These carbs came with my 68 Sloper. The other carb is identical to the one shown and also has the number 20 stamped on the side of it it as well, but I'm not sure what you mean by the choke butterfly. Are you asking whether the actual slide- down (choke) plate has a number on it? It does have what looks to be a number 2 embossed on it but it's backwards and lying on it's side, and very high up on the plate -almost out of sight. (I have not disassembled that part of the carb. Should I?) They both have that 'slide-down' restricter type choke thing actuated by the choke lever- as shown in the one pic. I envision a choke butterfly as a pivoting plate like my CB 450 has. I included that down-the-throat photo to find out if any of you familiar with these carbs would see anything missing on that slide -down thing. It looks somewhat ineffective to me as an choke mechanism, whereas those butterflies on my 450 carb seem to be very effective. I guess I'll find out more once I get this thing running.

As I mentioned in my previous thread- I can't imagine the PO replacing the original carbs with these. I'm convinced they're OEM, but I haven't been able to reach him yet. This bike only has about 3500 miles showing and the Speedo/odo was connected and working when I got it. It was very poorly maintained overall and I'm not sure the oil had ever been changed (the horror!) 'cause the crankcase was filthy inside. However, I didn't see any excessive wear other than what a very loose cam chain caused.

I did a lot of reading last night and today about these carbs and it seems they were and are quite finicky. The FSM is not helping me at all so far. I'll be going through them again-more thoroughly this next time- and will have some airboxes installed before I try to start it again.

The power jet assembly is a mystery to me as to how it affects how this carb operates, and I can see how it could be problematic. That vent tube is the most mysterious- it seems it could be submerged in fuel most of the time if not all the time, so it would be pulling raw fuel up to the power jets. But, the power jet circuit seems to be vacuum controlled but not tied to any other circuit. If it's boosting fuel flow at WOT (or at least half throttle) how exactly does it work with vacuum? I see a small vacuum port on the roof of the main bore, but how would that work once the throttle slide rises? Or, does it only work at closed throttle?

Since I had it running for a few seconds, I'm going ahead with Phase 2- getting it rideable and not just running. I've only spent a few hundred bux so far, but now it's time to replace a lot of the questionable stuff, and I'll need to clean the tank inside and replace the fuel tap- stuff like that. I'm looking forward to actually riding this thing. The list of stuff I need to buy just got a whole lot longer!
 
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