Derbi Senda 50/75 cc pre 2006

Discussion in '2 smokers' started by Navin, Feb 6, 2020.

  1. Navin

    Navin Long timer

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    Cross pollination of GPX and Derbi parts. It was bound to happen. Working front beam in place. Derbi headlight on display with my old number plate collection. Its too ugly to even be cute/ugly!

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    #61
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  2. Navin

    Navin Long timer

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    Vac petcocks gotta goooooo. Junk. Surprised it worked at all, not that it worked well. Usually needed an "oral prime" to get it flowing. Thankfully never any fuel in the mouth, just suck open the valve to get it flowing.

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    #62
  3. Navin

    Navin Long timer

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    And there she sits today. Less green (blech!). Running mean, for an 80 with no PV anyway. GPX headlight is no flame thrower but it would get me home at night if necessary. H4 bulb. Its brighter than the stocker by a good bit.

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    #63
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  4. mikeysduck

    mikeysduck Slow Ride to Nowhere

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    Lookin' Good!
    Are putting many miles on this? That front fender reduces the top speed by???
    #64
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  5. Navin

    Navin Long timer

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    Its up around 275 km now? The air box n carb slowed it a bit and require a down shift to 5th on our slight hills where it wasn't necessary before. It used to pull 100kmh everywhere, now uphills are 85, flats 100 if theres enough room.

    I might be a single main jet step too high from getting that right back. Its ever so slightly rich but it feels really good thru the mid. I can live with it like this. The current situation has me doubting a Rieju 50 Pro is in my near future.
    #65
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  6. Franque

    Franque Been here awhile

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    Dallas, Tx -> Aubagne, France
    Just keep riding it! I love that little bike. There's an air-cooled small displacement Cagiva 2t enduro in my neighborhood, I'd love to wring its neck.
    #66
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  7. greasyfatman

    greasyfatman Long timer

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    I have gotten a lot out of 80cc and air cooled. Know anything about the port timing? A53BFC72-69B5-4806-A585-5C36F33E9990.jpeg 73DA1E4C-2BA6-405D-B7D6-C62215FF2C94.jpeg
    #67
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  8. Navin

    Navin Long timer

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    I havent pulled the jug off, its good as is for my needs. I did drop the front sprox from a 14 to a 12t and the stock rear 48 is going on a shelf when the 52 shows up.

    Now if I pick up one of those Rieju AM6 engined bikes, theres a bolt on BB cylinder with a vac operated power valve I might just want to try. This ebe075 engine is just odd enough nothing really bolts in the top end. Thankfully it shares the gearbox (at least) with the ebe50. Crank and up to the head its kinda one off.
    #68
  9. greasyfatman

    greasyfatman Long timer

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    That bike looks like a lot of fun. I just zoomed in it’s water cooled that’s awesome, I need to look for one.
    #69
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  10. Navin

    Navin Long timer

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    There is a red one in Va for sale on Fb. Its a neat little bike, Ive listed mine on n off as Id just as soon have a new one but worst case if this needed an engine swap down the line (50/80/125/250?) the basic bike itself is pretty decent. Super mini sized but the 21/18" wheels are great.
    #70
  11. -Z-

    -Z- Been here awhile

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    Location:
    Aix en Provence, France
    Haha Derbi... they are great bikes! This was my first motorcycle

    I had a couple of thoses... They are very common in France Italy Spain Germany and others european countries.

    crankcase & gearboxes are similar for 50/80cc.
    Your one is a euro2 version, my one, on picture, is a later version, euro3

    They are bulletproof engine, my one was above 40.000kms still on original piston, never been rebuild.
    You can go up to 90-100km/h just with an aftermarket exhaust
    Original carb is Dell'orto 17.5 PHVA or PHBG

    They are still sold brand new nowadays, and some dudes fit 80cc or 100cc cylinders on it, it can go above, 30-35hp!

    Brand new price was 2200EUR in 2010...

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    #71
  12. Navin

    Navin Long timer

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    Any chance you could share the differences between Euro # engines? Ivd read there was a swing arm pivot bolt upsize at some point. And that these are Derbi build/designs that don't really match the AM6 engines, but maybe they use the same standard mounting points?

    Thank you!
    #72
  13. -Z-

    -Z- Been here awhile

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    Euro3 are different because they suits the new pollution regulation

    - different : cylinder / crankset / gearbox / cooling system / carburetor / exhaust / ignition & fairings

    So you can't swap parts between euro2 and euro3 but you could swap the whole engine as it got the same mounting point ( that's what internet says, haven't done it myself )

    and here are the different Derbi versions model :
    - senda
    - xtreme
    - drd
    - drd pro
    - gpr nude
    - gpr

    they all got the same engine ( euro3 ) but different equipment, Xrace model being the cheapest one, and drd pro being the top of the range ( usd fork, 300mm disc brakes, alloy exhaust ... )

    Derbi engine's are produced by Piaggio and used only in Malaguti & Derbi mopeds
    All the other brands uses AM6 which are Minarelli engine

    To fit an AM6 in a Derbi frame I guess you would need some adjusting here & there...
    #73
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  14. Navin

    Navin Long timer

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    Thank you Z! Good info!
    #74
  15. -Z-

    -Z- Been here awhile

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    You're welcome!

    I didn't knew that you guys in north america had some 50cc mopeds...! I only knew that there was some 50cc scooters in Quebec
    #75
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  16. Navin

    Navin Long timer

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    I think most were brought in the 1990s and not many survived. I believe there was a Derbi importer in Miami Fla back then. These bikes aren't seen very often on the East Coast anyway. A very odd duck. A few Aprilias got in too, less rare but still not common. Mostly the RS50 road race replicas by what Ive seen.
    #76
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  17. Navin

    Navin Long timer

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    The previous owner got me again last week. Rear flatted but I limped home on the 18 year old rear tire on the sidewalk... pull it apart and find 2" of the steel tire bead exposed on one side (WTF?) and about 3/4" of a flat head screwdriver tip inside the tire. No rim strip either.... not sure who to blame for that but its taped up now. New rubbers on the back for todays ride. In for a dime, in for a hundred dollars. :lol3

    The wheels mount crudely by modern standards. Spacers are loose and a washer between the rear caliper bracket and the swing arm. Not ISDT friendly in the least. But changing them is more like a bicycle tire than a moto so that parts easy. Barely needed an iron to pop it on.

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    #77
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  18. SloCalSpode

    SloCalSpode Been here awhile

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    Glad to hear you still have the Derbi
    I pulled mine out of the shed after two years sitting.
    Checked the air filter to make sure it was not crumbs.
    squirt some 2-stroke oil in the spark plug hole.
    It started on the third kick. Whoohoo!

    Attached Files:

    #78
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  19. Navin

    Navin Long timer

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    That pic brings me that much closer to dropping the $$$ on a new plastics kit and black seat cover.

    The new tires have a tighter tread pattern, cruise speeds up about 8-10 kph over the hard knobish stockers. Every little bit helps with these micro engines!
    #79
  20. Navin

    Navin Long timer

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    DERBI. WTF? The stock goofy radiator with an open to atmospheric pressure cooling system was jettisoned for a new KX85 rad ($50 shipped!) with a proper pressure cap. The factory top mount bracket got a 90 bend and a new L fabbed for the bottom, rubber mounted the rad and "close enough" for shroud mounting for this bike which had original wacky gaps anyway.

    The factory fan still works but I had to force it to activate as the bike ran cool even with the OEM bent rad and zero pressure system. In fact, the KX 1.1 bar cap was a match to an old Pitster Pro 1.4 bar cap so thats holding the coolant inside her. So the original fan is in the shop, I don't see ever needing it. Id need to pop a thermo switch on the rad if I did but eh, 2T so meh.

    Went 25 miles ridden from WFO 100kph to sitting at red lights at 97f, the big cooling test passed with a cloud of blue smoke!

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    #80
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