standard pk 50 tuning??? newbie low on cash

[covdave]

hi, i have a pk 50s, i'm finishing the body at the moment but would like to get some more go out of the motor as it's going to be my daily transport, i'm not after silly performance but i have 12miles each way to commute on various roads/conditions

what would yo say to fit, the motor at the moment has a sports pipe! dont know the make but it looks a decent bit of kit!

i was thinking of a piston/barrel kit?

any other mods that will make it a reliable daily would be helpful too, its a kickstart & has the leccy coil, non leccy start

also, i've lost my keys, what do i do?

also what realistic speed/cruising can i get from this little 50+cc motor when tuned a bit! i have a lightend pk flywheel for it to! i dont want to fit a race crank just the basics to get it going

cheers all

[covdave]

i have been looking at this kit, obviously needs more bits/cash??? hmmmm i'll have to think hard!
www.sip-scootershop.com/pages/index.php?ID=14480&EXPLODIM=px&_requested_page=%2Fpages%2Fdetails.php


i also thought of the 110/112cc cylinder kit

what is going to get me my best bang for my buck

[me]

PK crank is a good bit of kit anyway so no need to change that for a basic tune.

You could tune the 50 barrel with a bit of work to the exhaust port, and a bigger carb 16/16 or even a 19. would see you good for about 50-55, one of the biggest restricting factors on the 50 is there primery drive (gear) what ever you do your gonna need to upgrade the primery, maybe a standard 90 primery on a tuned 50 would be best.

Ploini and DR do a good basic kit for the 50 crank

[covdave]

the primery, is that the gear that takes the drive from the gears to crank?

is this a fairly easy-ish swap??? if there is any link reguarding this or what part to by would u/anyone pop it up!

just stripped my fork today & got to change the bearings & pin :oS

so a bigger carb barrel/piston kit & the primery? & i should have an ok tune motor for a daily!

what would i need to do to make it have enough go to hit 70/75mph?

if its too costly to get it to hit 70mph the 50-55 is enough for me!

if theres any links to how to do this work at home plz post them up, i do appreciate it

[Juan]

TBH I'd forget about the 70 mph bit unless you want to spend fairly serious wedge.

If you're happy with mid 40's flat out then go with a Polini 75cc, 16/16 or 19/19, left hand pipe and the Polini rectangle clutch spring still running standard gearing.

If you're happy with mid 50's flat out then a Polini, Pinasco etc 102/ 112 with a 19/19, lhp, clutch spring and 3.00 gearing.

Gearing swaps are fairly easy, here's a link.

[covdave]

my exhaust is an expasion type & exits on the hub side of the engine, its quite short!

i think 50-55 sounds pretty good, i'm nearly finished doing the body & other mechanics, suspension & brakes, just new cables to fit after painting so i'll have to pop pics up of my engine/scoot body!

i'll have a proper look at the engine then!

any best/safest methods for geting it started out of the scoot! mine is a non-leccy start model

[ozzy]

for running out of the scoot; i made up a little stand out of bits of steel. i've also seen them made out of wood before if you don't have any welding kit. make it pretty sturdily as kicking the engine over is quite a load.. then you just need some kind of auxillary fuel tank... you can balance your vespa tank somewhere or you can buy and auxillary tank, i just got one from a bike shop who let me have it at trade, £11, its a nice little plastic 1lt thing with a tap and chain so you can hang it... i've also used fuel bottles from r/c cars, they about £1.50 and have a nozzel that you can just fit fuel pipe over, then when you've finished with it its great for filling the oil up

o

[covdave]

what a bonus i have an old fuel bottle from a remote control car!!! nozzle is the right size for the pipe too after checking it! ;D

right checklist for running the standard 50cc 4speed out of the bike

frame to mount the motor - making it!

engine
fuel & 2stroke oil
fuel pipe
carb
black box with the ign lead to the plug, black box is refered to as the cdi is'nt it???
air filter
exhaust
patiance

what have i missed? if anything?

i'll operate the carb by hand, i think its best to check the engine like this before it go's in the bike to set it up as best i can without using a rolling road or before further tuning really

i'll try to do a little video on my phone, i'll probobly be checking the search & making a few posts for advice on this & that anyhow

any critasism/advice is welcome,i'm new to 2stroke/scooters

[vinrouge]

Hi Dave,

From what little experience I've had, from bulk standard pk50 get about 28mph on flat, no more, uphill well lets put it this way I wouldn't have wanted to have got stuck behind me, could walk faster.
Polini 112 kit, with polini lh exhaust, 40 on flat, hills no longer a problem, much more lower end grunt, confortably handles local traffic condition.
Still got 16.10 carb, this should be changed next week to 19.19 so I let you know effect on performance.
Rob

Btw you'll need a manifold

[covdave]

any update on 50cc+ performance???

still a little unsure what to go for for my engine ?

whats the biggest cylinder kit i can put on & the right carb size to match, can i use a carb from a px (if its the right size-ish)
i will get it setup properly to get the best of it

my budget is going to be around enough for a piston barrel kit & decent 2nd hand carb, i'll try with the exhaust i have as it is'nt standard but cant make out the brand???

painting the frame/body this week on a dry day so things are moving well

[Juan]

Biggest kit you can fit on the standard crank is a 112 but it depends on if you're up gearing. If not then a 75 is your realistic maximum.

A PX carb won't fit, they're completely different.Smallframe carbs are side draught while large frames are down draught.

If you're staying on standard gearing then the 75's can go really well (comparitively) if you use a 16/16 or 19/19 carb, manifold and uprated clutch and spring.

[covdave]

right chaps i've been struggling to find an exhuast the same/simular design to the one i have, just to get your opinion as to wether its any good, anyhow its seems to be the same or very very simulat to this one on the link below



is this design any good, mine as i've said i belive to be a stock 50cc

any help always appreciated

[Juan]

That's for a reverse barrel, it won't fit.

[jonnysnatchsniffer]

unless you reverse the barrel