Polini Powered Home Built Bicycle Motorcycle Conversion

Polini powered home built scooter

Polini powered home built scooter

Got a note from Derek about a trip he took to Seattle. He was walking down the street and came across this really interesting home built bicycle conversion locked up in front of a theater in the university district. The owner and/or builder was obviously using it for around town transportation and Derek thought it was a great example of the type of small displacement homemade scooters he saw much more of in the west than back east. In fact, he observed it wasn't until he was west of Denver that he really started to see scooters and mopeds anywhere.

Polini powered home built scooter

Polini powered home built scooter

From the photos, it appears this moped/scooter/mini motorcycle (NOT a moped, no pedals) is powered by a liquid cooled Polini 2 stroke engine, the frame may have started life as some sort of BMX unit with various parts and pieces found, made or modified to serve the needs of the build.

Polini powered home built scooter

Polini powered home built scooter

He had no info about the bike other than what you can glean from the photos but, like Derek, I think it shows some real ingenuity on the part of whoever built this. If anyone from Seattle recognizes this bike, maybe even the builder, we would be glad to hear a few more details. Pretty cool example of the kind of really inexpensive build you can create with a little outside the box thinking.

Thanks for the photos, Derek!

UPDATE: I changed the title of this post and removed the word moped. I agree with the comments, without pedals it isn't a moped.

Polini powered home built scooter

Polini powered home built scooter


  1. says

    Hi everyone, from my french point of view, it appears to be a french moped but the engine is totally changed and upgrade with competition parts and the rear tubular frame is very particular.
    it’s strange to find that kind of vehicule on the west coast.

  2. trickMETRIC says

    Well, it’s not a moped. Us moped guys are pretty critical about scooters and motorized bicycles without pedals being called mopeds. No pedals… not a moped.
    We defend this distinction for legal reasons. In many states, to be legally registered as a moped, you must have pedals. Many people register vehicles that they can’t legally register any other way as mopeds. This makes the cops suspicious of anybody with a moped tag. It also gives state legislators incentive to drastically change moped law. Go ahead and call this bike a scooter. But it’s not a moped.

  3. Kenny says

    Don’t think there are very many bicycle components on it unless that front end is off a bicycle. Though it looks more like something you’d find on a NSR 80. I love the way the owner has a spare drive belt slung over the handlebars, it puts emphasis on the utilitarian nature of the build and perhaps the owner. I’m just curious, how does it stop? I see two levers and I’m assuming one is a clutch (unless it’s an automatic). Does it have drum brakes?

  4. kneeslider says

    I probably shouldn’t have said moped, especially because the “ped” portion of the word implies pedals, but I was searching for the right words to describe this and I wasn’t exactly sure what to call it. I changed the post title and the image captions removing the word “moped.”

  5. says

    Now i got some informations: you can find many of that kind in my country –> France.
    – Motob├ęcane 51v model wheels and fork.
    – frame from Peugeot 103 (mvl, sp,spx etc) moped cutted and rear frame customized with iron tubes.
    – many competition parts from Polini.
    – variator Malossi.
    – clutch in the pulley like Peugeot 103 spx model but customized in aluminium.
    – Polini exhaust probably.
    – Peugeot 103 seat.

  6. marc says

    french myself and agree with mafieu….did not see one those kind of machine since i was a teenager….

  7. Scotduke says

    I race BMX bikes as it happens and yes, that does look like the remnants of a BMX frame there. The toptube and headstock have been retained, as has the downtube and the frame cross piece that would connect the bottom bracket where the cranks are to the seat. The rear of the frame has been cut away to make way for a swing arm. the tank looks like it could have come from a Mobylette or Puch moped. The cooling system is a neat touch. A BMX frame would be a good choice actually – they tend to have large diameter tubes and are made from much thicker tubing than most other bicycles to cope with all the shock loads they have to endure.

  8. rafe03 says

    Saw a BMX bike at a garage sale on saturday. $40.00 OBO Shouda snapped it up! F & R suspension; Big tube frame; Hefty tires; Spoke wheels; Etc.

    Did I miss a real chance? Now, where was that house?

  9. Clive Makinson-Sanders says

    I have several questions including the one about brakes… is that a dry clutch? Where are the wires? Why is there a bungee cord looped around the final drive belt? Why isnt this guy mass producing these? and how much would you pay for one…. id say 2000-3000 beans.

  10. nortley says

    I was wondring about that bungee myself – some sort of anti-theft nut snapper? I love the machine, there is true owner involvement.

  11. doppio says

    I love it, nice ride.
    I’m with Mafieu on the Peugeot origin of the bike… I’m French as well and happen to live in Seattle… I commute on a bicycle and ride in the U District almost everyday. I’ll keep an eye out for the bike and its owner… From the pics background, I think I know where the bike was parked.

  12. Gareth Matthews says

    I saw this bike last Wednesday at the Backfire meet in Ballard, Seattle. Thought it was very cool at the time, I know the Polini motors can make some pretty respectable HP figures for something that small. There was a lot of weird and wonderful moped / small motorcycles at the meet, wort a visit if your into that kind of thing.

  13. says

    Really nice.I like the triangulation going straight to the top of the rear shocks.Started life as a Peugeot 103 I think.You can have a lot of fun with 50cc machines.I am currently fiddling with a Puch Maxi.You should see some of the great and crazy customs based on these .Also they can go fast and they are so cheap to fiddle with too.

  14. says

    this bike belongs to the nazty naz and it is a peugeot moped that he has heavily modified. despite the lack of pedals, it is a moped. it came from peugeot with pedals, and naz removed them.

  15. Scoop3 says

    as mr. terrydean said it… Peugeot 103 +Naz Magic = one of the gnarliest mopeds in seattle.. ­čśÇ

  16. kneeslider says

    Well, one of you that knows Naz, ask him to stop by and enlighten us. This is outside the bounds of the normal fare here.

  17. naz says

    Frame: Peugeot 103 tank with modified with thin wall chromoly tubing for the rear triangle of the frame.

    Forks: Factory Peugeot at this point but have some some hydro forks going on soon.

    Wheels: They are of a Motobecane and where converted over to sealed bearings and powder coated black, Thanks RJ for the trade!

    Radiator and Circulator : KTM50 radiator with some simple brackets made to mount it up with Bosch 12V water pump.

    Engine: Polini engine cases with a Doppler brand crankshaft and Malossi GR2 50cc LC kit using a Doppler made expansion chamber using a little 16mm PHBG Dellorto carburetor.

    Ignition: Ducati Energia made system sold by Malossi who builds the backing plate and distributes it. I use the 60watts to run the headlight and also convert to regulated DC to supply power to the 12VDC bosch water pump.

    Drive Train: Malossi Variotop Variator with a Gates Brand AX32 belt running to Doppler “Clutch Pulley”. The clutch is dry and dimensions match up to most 150cc scooter centrifugal clutches. Oh and 11×56 gearing at the moment going to 11×54 or 11×52 soon.

    Bungee: Used to hold down the u-lock for riding around, I just leave it on the bike when I lock up the bike.

    oh and yes it did start out life as a moped with pedals and might make it back to being a moped, but haven’t taken the time to build a new pedal shaft yet. The grips are from a BMX shop since I prefer longer grips instead of short grips.


  18. GenWaylaid says

    I’ve seen some pretty extreme custom mopeds down here in the Bay Area, but it’s like Naz has combined the most extreme elements of them all into one bike!

    Mopedders tend to heavily modify almost any moped they ride on a regular basis. When the stock version only goes 30mph, there’s a lot of incentive to make changes! All of those slow mopeds sold back in the ’70s are now cheap raw materials and parts for barely-legal customs. It’s amazing how unique a bike you can create for $1000. The Moped Army site has lots of interesting photos (www.mopedarmy.com).

    By the way, mopeds aren’t just a Western phenomenon. In addition to the major cities on the West Coast, there are many clubs in the upper Midwest and a few in the cities of the Northeast as well.

  19. David says

    I enjoy the fact that there is a great amount of Mad Max in all of us and invention is its mother

  20. Marc says

    Considerating its tuning and its supposed speed, I would call this thing a rocket… Is it legal in the USA? In Switzerland: no chance! Greetings!

  21. FREEMAN says

    Interesting ride. I like it. If I’m ever in Seattle I’ll be sure to keep my eyes open for this one.

    To those wondering about the brakes. You can see the front brake line in the very top left corner of the picture of the radiator. You can also see it in the first photo if you zoom in on it. It’s just behind the front forks. This line appears to run to the right hand side lever like a traditional front brake. The other lever is probably the rear unless it’s a manual. Is it a manual?

  22. naz says

    both levers actuate drum brakes at the moment. Pretty traditional moped kinda stuff, it stops ok but I would love to have better brakes. Oh and since it was a moped, it is a automatic :-)


  23. kneeslider says

    naz, thanks for the rundown on all of the work you’ve done. That’s an impressive bit of moped reengineering. Personally, I wasn’t aware of the level of work you and other moped enthusiasts have been doing on these 2 wheelers. Nice job!

  24. Pete P. says

    Just FYI. Legal definition of “moped” here in VA does NOT mandate pedals.
    Only three criteria, according to VA law.

    1. Seat height > 24″ (to keep micro-bikes off the road).
    2. Displacement < 50cc.
    3. Top speed < 35 MPH.

    Mopeds may be operated without license, insurance, registration, or helmet (state law, local laws may supercede). They are indeed popular in the Eastern cities, but the suburbs are tough places for 35 MPH vehicles.

  25. Paulinator says

    So I wasn’t imagining it. The French are really big on these things. When I was in France 15 years ago, crossing the street at a corner was a high-risk proposition. You’d get half way across before you heard the high-pitched crackle of a radically tuned little 2-stroke on the pipe. Those things can drag their handle-bars in a turn! What’re the stats for moped-padestrian collisions in France? If I ever make it back there I’ll wear goalie pads.

    KOOL RIDE!!!

  26. todd says

    This one, for sure, would beat my modified Peugeot 103. Mine looks mostly stock but I did a bunch of work to the motor just to get the thing to go over 40 mph. There’s definitely some room left for more.

    Mopeds are great fun but they don’t get respect from either motorcyclists or scooteri. Go to a pocket bike race and you’ll find a venue for moped racing as well. Great fun and quite a counter culture if there ever was one.


  27. Eddie says

    I love it. In my mind this is the real engineering. Art.
    Just as it should be to do the job. I love the frame. If you have more detailed pictures, please post it.

  28. CanyonCarver says

    The base for this project is a Peugeot 103 SP. I had one in 1982 and modified it with a Simonini 80cc kit. It was air cooled at the time. It actually looked very much like this one. The rear section of this frame has been modified.
    Peugeot moped came with pedals but we used to buy billet aluminum pegs that were mounted in place. We would bump start it. Easy.

    This machine brings back fond memories…

  29. Dudel says

    With a BMX frame it would have been more properly called a motorized bicycle. As it stands, I would describe this as a moped converted to a mini-motorcycle. Anyway, it’s a great-looking bike regardless of how one describes it. I also live in Seattle and am building a mini-motorcycle (mini-chopper) with a custom bent tube frame and a 96cc (49cc base) scooter engine. On the BMX theme, I would love to build a mini-motorcycle using an aluminum or carbon-fiber bicycle frame as a base; a sub-100 pound bike in the 10-15hp range would be fun around town.

  30. says

    I hope to build something like that one day. I would love to know more about the transmission. I’m working with a 05 TFR, I was thinking of a dual variator setup or something. Thats the kinda post-appocoliptic stuff I like. Looks like something from Road Warrior or Barbed Wire.

  31. says

    Peugeot 103
    The top half of the frame is all custom, but the engine, swing arm, seat, and forks are all from a Peugeot 103.
    The motor case is the upgraded Polini kit with the watercooled top end. It would normaly have pedals but they have foot pegs sliped over the ends of the shafts.

  32. says

    Hi there

    Funny to see all the french guys waking up on this site, to the sound of the so famous 103.
    I guess during the 80’s one out of two french teenager had one like that, and there was so much challenge around the tuning of this thing that you could see a guy on his 103 bypassing you at 60mp/h + (specially in Reunion Island where I live)
    Now that the teenagers are grownup, people start to rebuild and collect those jewels :)

  33. WillD says

    Totally a moped
    and if it’s not, it’s not for the lack of pedals, its the oversize engine, that makes a bigger legal deal in ALL states, not just the few with the pedals distinction.

    Anyhow, I still consider it a moped because it was designed with pedals. It’s a moped with the pedals removed. It’s still a moped.