Anyone know anything about a motoforce 17.5mm carburetor with a manual choke?

Harddog96

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So I just recently got this I should go ahead and start by saying no I am a novice I just started May 26 working on scooters I don’t have a mechanical background I just figured why not learn on something small, so I’m rebuilding the whole motor from top end to the clutch, variator, intake and so forth. I bought a manual and I’m good at instructions or learning from someone hands on. But I digress. I can’t seem to find anything about this carb in particular. I know it’s a phva carburetor. It just has so many port’s on it I see the gas and air also the throttle and choke . I’ve decided to delete my oil so should I just seal the rest up with plugs? Or which ones need to not be sealed?
 

Harddog96

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You seem to be on the right track, I also started with no experience years ago.. the key is patience, use your camera, take pictures of the breakdown and you can rebuild anything. Good luck and have fun. You have found a good source of information here!
Yeah I forgot to take pictures of the breakdown but I did end up buying a manual so that has been a godsend.
 

Harddog96

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So the cast one is definitely down to the float bowl I had that little black tube connected to the two brass fittings and then I ended up disconnecting it. Each step and each version I tried still wouldn’t draw gas. I don’t know what else I’m doing wrong
 

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Chainlube

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I would take a plastic soda bottle with a hole in the cap, fill it with fuel, put a hose in the hole, and use as remote fuel cell, then try each of those barbs. I think the top one on the left in your last photo is fuel in. Take the float bowl off and use your remote fuel cell to determine which is fuel in.
 

Harddog96

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Well I finally got it it took putting some gas in the carburetor just squirting some in there with the squirt bottle in the compression from that made the petcock start working, I’m currently breaking it in now with heat cycles. I bring it up to 210-250 and then let cool down. Only thing im gonna need new throttle and choke cables soon.
 

Harddog96

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So it starts runs and idles fine. But I heat cycled 5 times and then the 6 start I tried to drive it. It started to go at 3000 rpm and only went max around 6800 before it died down and bogged out. Um I have the heavier of the variator rollers in also put the more stiff contra spring in. Could any of that be the cause?
 

Harddog96

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This seems too loose, no?
 

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Harddog96

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Did you try revving it up with the cover off? The driver should move in while the driven moves out. The belt could be stretched though.
It did. I’m a tard. But, I gas it and it revs to about 5k and goes to take off then dies down immediately. I checked carb float bowl, and only have the oil line plugged.
 

Harddog96

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Well so I had to mess with the air screw and tighten it all the way and only did one turn out so I think my pilot jet needs to be bigger. other than that the RPMs is what gets me. it doesn’t takeoff to like 3500 and then sometimes when I let off the gas after going say 30 mph it’ll stay revved up all the way until the stop sign and then like 5 seconds or so after. I did have the heaviest variator rollers, clutch spring and contra spring in. That’s what I initially thought was making it not takeoff. So I swapped it out with the lightest weight stuff but I don’t think that would make my bike rev more. I would feel like that would make it rev less.
 
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