PA50 engine swap

Hi all,

OK... just got the moped bug, and have a PA50i and a PA50ii.

The PA50i is immaculate... 1979, 350 miles, the PA50ii is 1978, 4000 miles and has been sitting outside unused for quite a while!!

I worked on the i for a few days (carb and petcock cleaning primarily) and have that running pretty good, but it tops out @ 15MPH (I am 120lbs), won't idle and has a completely "wooly" throttle response.

I would like to swap the engine from the ii to the i, because the running gear on the i is so good and I would like to hit the magic 30MPH!!. The question is, is this a straight swap??

I have found the shop manual online, and removing the engine does not look to difficult... but, when I come to install it in the i chassis, will it bolt in the same way?? Will the belt be OK?? etc, etc.

I really would appreciate some assistance... y'all have been invaluable so far!!!

Thanks a ton,

Ian :)

Re: PA50 engine swap

The swap is pretty much straight forward if you use complete motor and carb setup. The only other thing you'll need is the snorkle for the air intake, it has larger holes then the one on the PA50 I.

Re: PA50 engine swap

ian rattray /

thanks!!! I have the complete PAii, so perhaps I can try and transfer it from that...

Thanks again...

Ian :)

Re: PA50 engine swap

On a pa50 you can probably unhook the wires and cables, remove the bolt for the pivot and the two lower shock bolts and swap the whole engine/subframe/wheel no problem.

Re: PA50 engine swap

ian rattray /

very good idea!!!

I will check the condition of the whole sub-frame... if it is OK, this would be a very easy way to do it!!

Thanks a ton,

Ian :)

Re: PA50 engine swap

too easy

Re: PA50 engine swap

ian rattray /

... it is amazing the engineering logic... 3 bolts, a couple of cables, and the whole sub frame is laid out before you... :)

Now... getting the 30 yr old carb cleaned out is another issue!!! (it's amazing what a can of carb cleaner will do to the moisture content of the skin of the hand that is holding the carb parts while they are being sprayed!!)

Is the carb on the i VS the ii the same??? Or is the ii carb bigger???

Thanks again guys...

Ian :)

Re: PA50 engine swap

DUDE, the reason you go 15-17 is because the variator is PermaStuck.

Buy a TJT variator and ramp plate for both, or notch the variator in the WIKI.

The TJT and a Proma exhaust guarntee a 44mph downhill tuck.

I swear thge variator is fucked, buy new weights and sleeves and slider ribs for plate or just fold, and get the TJT. With Polini medium weights.....totally awesome.

Re: PA50 engine swap

that's what i'd do. first, i'd get the PAII running. from there, it's a 40-minute job.

Re: PA50 engine swap

ahhaaaa... I would never have thought of this... I will give it a try and I move through this adventure!!

Thanks... :)

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