Lambretta auto ( 125 skipper a/c engine )

Discussion in 'Maxiscooter Tuning' started by skibretta, Jul 2, 2009.

  1. skibretta

    skibretta New Member

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    Hi just looking for some advice on tunining a skipper 125 a/c engine ...
    Have done a search and seem to be confused with peoples aproach to tuning ...

    at the moment the engine is standard apart from a scorpion exhaust as this was easiest to fit with the lambretta bodywork ..

    I am looking to fit the 172 a/c cooled kit as a start but as said above am confused as to use a bigger carb , different variators , clutches , up gear kit ..

    I have ridden tuned lambrettas for years but this is my first venture in tuning autos ..

    any help with a basic set up much appreciated ...

    Thanks in advance Justin ...
     
  2. 2stroke-power

    2stroke-power New Member

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    basic fast reliabal setup would be ,mallossi 172 kit 25 ml carb ,mallossi rollers and belt ,uprated clutch springs,gear up is a must ,and a performence pipe ,jolly moto ,mallosi or polini ae the best pipes if you want more speed go for ,aftermarket crank ,porting work and some kind off billent head ,mallossi cdi ,,,alll depends on what it is going to be used for .wekkends ,daily use once a mouth whats your plans
     
  3. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    no billit heads are avalable for the ac engines... but yes all the above is about right..
    the malossi cdi wont fit onto the ac stator (well it fits but the timing is incorrect so the engine runs backwards)

    one of the BEST mods on any ac engine is to fit the wc stator flywheel and cdi. you need to tap the holes in the flywheel to take the fan screws but other than that its a bolt on conversion and instantly revs more frely.. the timing advance on the ac cdi is absoloutly pants and THIS is the ONLY reason the ac's are slower than the wc bikes. as far as bolt on or even semi ported setups there is no need for the hassels associated wiht the POOR wc system's used on these engines.. more to the point the main advantage of wc over ac is even heat disapation wich means you can go finer with the piston tollerance... even tho the wc ands ac have the SAME poor tollerance.

    wc is a WASTE of time ion my opinion (unless of course your a commuter siting in lots of traffic or all out race bikes) ac is king of simplicity and power for less cash
     
  4. skibretta

    skibretta New Member

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    Thanks for the quick replies ..

    Just a couple of questions ..

    I have got a couple of 25mm carbs that i have used on lambrettas before obviously thes are not autolube ...

    Can these be used by premixing in the tank and do away with the autolube ?
    Whats involved in disconnecting the autolube is it just a case of removing the cable that runs into it ?
    Are up gear kits easy to fit or is it a big job ?

    sorry for all the questions ... Justin
     
  5. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    if you wish to run premix then do so as you normally would (i prefer this way tbh) can completly remove the oil pump/drive gear (gives you a little more power/free revving) throttle cable is better to replace with a single peice (no spliter as there will only be one cable)

    you CAN just bang up an oil tank and drill a hole in the carb for an oil nipple... ive done a fair few now. considdering the 25 from dell is 60 quid, but with a vac and oil nipple its 110? malossi are wankers

    but ye, wants around a 106 jet, needle top possition (think its a 73 needle? NOT the fat one's, nice an thin needle) slide leave alone for now, idle mix dependant on the jet tbh..

    any probs just post here and we will do our best to sort it ;)
     
  6. 2stroke-power

    2stroke-power New Member

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    must off been high ,didnt clock that it was a/c ,,so yer no billet head but yer ,w/c stator and mallossi cdi, the way foward , :
     
  7. gulliver

    gulliver Member

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    any pics would be nice of your bike
     
  8. skibretta

    skibretta New Member

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    Ok the 172 kit turned up today bit of a result at only £220 from Kegra every where else wanted about £260 ....

    I have plundered my 135 mallossi vespa smallframe for the 25mm carb and up gear kit is on order should be a couple of weeks ...

    Still trying to get my head round the whole roller weight and cutch spring thing ...

    any ideas as to a starting point regarding roller weights and clutch springs ?

    Sorry for what may simple questions to some but after 12 years riding tuned smallframe vespas and lambrettas automatic gearboxes are a bit different for me....

    Thanks in advance Justin ...
     
  9. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    easy.. if its a wc start at 13.5 if its ac start at 12.5 on the rollers.. clutch springs always run blues.. ALWAYS
    contra spring isnt needed at this stage really so we can get back to that bit. roller guide in the guides section should give you the info you need to know on how it works and why it doesent when it doesent.. they are usually pipe dependant but the stock unported malossi kit is VERRY passive, it will run with many wrong weights and show no sighns of performance loss to the untrained ear. the weights given are prittymuch baseline/benchmark roller weights for any bolt on setup altho playing wiht them will give results (some go as high as 15g some as low as 7 but its all dependant on port spec and pipe)

    the 25 carb will need a 106 mainjet 56 pilot and the needle on top position (altho it may be a different needle.. think its a 73 needle, not sure) if you get stuck somone will gladly pull there needle and give you the "malossi" needle code that works wiht the 172's. jet correction kits are a fucking waste of time and money. just get a range of jets, set it as above and play.. again theres a couple carb guides in the guides section, one simple, one advanced.. good luck
     
  10. skibretta

    skibretta New Member

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    Thanks minor for the quick reply ....

    Will have a look at my carb tonight have got a rake of spare jets and needles from my lammy and vespa spare dellortos ...

    Just another quick question can i still use the standard variator and clutch with the kit ,carb and up gear kit ?

    And just replace the rollers and clutch spings as you have suggested ?

    Thanks again ....
     
  11. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    ye of course.. just match thew size, start wiht pointed needles not round ones (verrty vague i know but the sizing on needles is strange and i cant be arsed to look it up)

    springs go in the stock clutch, thats the idea ;)
     
  12. Blue dwarf

    Blue dwarf New Member

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    342
    Prob been said before but check your roller sizes.

    Std 125 takes 19x17mm and not 20x17mm although they can be played around with by shimming the variator (best not go there just yet).

    Gear up is a must with the 10" wheels of the Skipper and 172 kit or you will over-rev and stress the kit.
    Red Dwarf is a hexagon based engine and runs 10" wheels (fastest thing on 10" inchers in the world ? lol!) and the gear kits are a mine field, just make sure you get the right one,forget primary kits for now and just go for a Malossi secondary gear kit but check the year for your model, some take a spline fit and others a press fit.

    \just did a search for you and it seems no one lists a gear kit for the Skipper 125 on 10" wheels!!

    My bet is it`s similar to the Hexagon 125lc and I know we`ve fitted a skipper kit to the Hex so if I remember i`ll post part numbers after the weekend testing at Pod.
     
  13. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    just to add, the tyre size makes up for the lack of diameter on the wheel (10" wheel uses an 80 profile) where as the 12" uses a 60 meaning 40mm less circumfrance on the tyre wich is actually pritty similar..the 20 of the profile means both tyres are pritty similar size (ye the 10 is still undersized but nowhere near as much as 2") using low profile tyres kills this effect.
    go for the lowest ratio secondary you can find for your engine type (whip the gears out.. the ley shaft (in the middle) will ether be splined or pressed and the oputput shaft the opposit.) its not dependant on old or new shape engines tho as both old and new CAN use the same gear up if pressed correctly.. its the difference in the output and ley shaft not the imput shaft (imput shaft is the difference between the old and new shape engines)

    all the press fit gears seem to be OLD OLD engines as fitted to the hex/skipper and SOME of the typhoon engines (the big engine number version with the silly small crank) ill be having her gearbox out of the misses bike after iow tho so ill throw pics up of everything i have klying about. :)

    but ye.. whip the gears out and throw a pic up (get one fo the bike wihile your at it) im sure the dwarf's or myself can imediatly tell you the gear up type needed and help with what ratio to use.
     
  14. skibretta

    skibretta New Member

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    Thanks for the replys ...

    Sounds as if the gear kit is going to be a pain in the arse then ?

    Anyway taking it for the mot this afternoon so will start tearing it down at the weekend will try and get some photos of gear type and a couple of the bike ...

    Only problem being i'm good with spanners but shit with computers and only have acess to a works one ....

    If i email someone the pictures could someone perhaps whack them up on this thread please....
    :)
    sorry to ask but i am really that shit with computers and have limited acess to one guess i'm old school and would rather spend time in the garage than behind a screen ... :)

    cheers Justin ...
     
  15. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    of course..... can email me or the main site email address (terro will have to deal with that)
    but ye happily throw some pics up for ya. email is in my profile/the site email is admin@scootershack.co.uk (i think) LOL

    this doesent mean everyone should add me to msn btw... yes i have email, yes its my own email not bike related usually
     
  16. skibretta

    skibretta New Member

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    Cheers minor ...
    I must be bad with computers as i can't seem to see your email address on your profile....
    You can pm me it if you want i know how to retrieve those lol ...

    By the way don't expect some show winning series 5 lambretta conversion with trick paint ...
    Just my old series 3 LI italian import iv'e had about 8 years battered and abused :)
     
  17. Purplepill

    Purplepill Member

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    He's right minor, I couldnt find your email in your profile.

    Iv just PM'd it too you skibretta.

    He's on the Isle of Wight until monday though so i'd send the pics to the admin email address he gave you it'll probably* be quicker.....


    *- You never know with terro :whistle: :mrgreen:
     
  18. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    back now, wil sort them in the morning ;)
     
  19. skibretta

    skibretta New Member

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    No worries ....
    Been busy myself all weekend ...
    If i get time i'll pull the engine out tonight and get some pics of the gears for you ...

    Cheers Justin ...
     
  20. MiNoR cOnFuSiOn

    MiNoR cOnFuSiOn Administrator Staff Member

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    nothing waiting in my inbox.... ive pm'd you my email again
     

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