I recently bought an old Motobecane Mixte and i can't figure out which model it is or what year it is. It has a 1020 frame, Pantin head badge, Dia-Compe center pull brakes, Solioa crank, Weinmann brake levers, Jet seat, and Huret derailleurs. I can't find a serial number on the frame.

i don't know, but i'll guess...

given the 1020 frame w/o a derailleur hanger, the cottered crank, stem shifters, i'll guess a '70s era nomad. strange you didn't find a serial nbr on the underside of the bottom bracket shell. although, if found, would not lead you to determining the year or model (most likely).

really nice moto step-thru frames like the mirage/super mirage are incredibly hard to find. with exception of the fender color and fit, yours looks like a bike in very good shape.

My guess would be a mid seventies Nomad. Have a look at this page.

Anytime you are trying to find something out about an old bike, try adding the word "catalog" to the Google search. Surprising what will pop up.

From what I've seen looking at the catalogs online it doesn't look like a Nomade. It looks like Nomades don't have chrome on the lower forks and the spec sheets in the back of the ctalogs show the Nomade as not having a 1020 frame. The only bikes with 1020 frames I've seen in the catalogs are the Mirage, Grand Toring and Jubile. The headbadge is different in the mid 70s catalogs as well. My headbadge is two winged helmets face to face resembling the winged M. It says Motobecane above and Pantin below. I've seen other bikes with this headbadge online, but I haven't been able to figure what era these were used.

Hi Lumpy welcome to the forums. Perhaps you could post some more and better pic? I am sure a close up of that headbadge would be useful. Also what country are you in? Alot of the members here are in the US and we usually compare posted bikes to what we know about US market bikes but, like cars, bikes are built for different markets.

I am not a follower of Motobecanes but I agree with T-Mar that the flat bars were likely added later in life.

I appreciate all the help with this. Here are some more pics. The 3rd pic is the headbadge, the 4th is a sticker on the frame on the seat post. You can see that some of the welds are painted gold, I don't know if that helps.

I looked at the frame under the crank and it is stamped 609. Is this the serial number? It seems like a 3 digit serial number is hard to believe for a company that's been around since the 20s.

My guess is a Mirage, with the chromed fork socks, very early 70's. The next step up (Gr Touring) would have had DT shifters.
AFAIK, the "Pantin" badges were used up to the 70's when they were replaced by the round badge.
I've seen them on 60's Motos but I think the Pantin designation goes back further because Pantin was where Motobecane had their factory.