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i haven't ridden it today, but i will sometime tomorrow.
problem is my backyard it too small to wind it out wot.
i might have to knock up a backyard dyno to run/tune it on
 
i haven't ridden it today, but i will sometime tomorrow.
problem is my backyard it too small to wind it out wot.
i might have to knock up a backyard dyno to run/tune it on

use your street:p its not too loud for it is it?
 
Sounds good mate, give yourself a pat on the back, you deserve it. Now fang it down the street and see how she really goes:grinning-smiley-003
 
nah sorry, i'll give it a miss,
and wait for the backyard tomorrow.
 
been raining here off and on for the last few days.
i have linished the welds back of the expansion chamber and given it 2 coats of black.
needs 1 more coat then will spend an hour inside the oven at 200 degrees, while the wife is at work that is, lol

 
i have just finished doing some baking.....
mmm, smells so nice in the kitchen, lol





now to let it cool, give it a buff then fit it back onto the PW again
i will run it for a bit to harden it more, then remove and wrap it in some heat wrap
 
refitted, and has had 20 mins run time at various throttle settings.





 
nah russ, i haven't swapped the bigger main jet in yet, too much else on the go as per normal, lol

i wrapped the expansion chamber today, using some High Energy heat wrap, cost $18 for the small 2" wide roll.
i had the clamps left over from a Thermotec kit i got years ago.
it is a bit awkward to wrap with the tapered sections, but i think it should be ok.
i let the pipe dry out in the sun for a few hours today, a then ran the bike again for 15 mins or so.

with the bike running, it almost sounds like a YZ80, or a smaller MX bike like a KX60 ?, very crisp now.
it is a touch lean in the higher rpms when held flat, it surges a little, so i think with the 67.5 Main jet fitted it will be perfect.















hopefully Cj wont burn himself now, he has a scar from the first time without trainer wheels.
i can hold my hand on the wrap for maybe 5 seconds on the header pipe before it gets too hot.
the rest of the pipe stays pretty cool, it should give it a cooler intake charge too,
with less heat being radiated towards the carby and airbox,
i reckon the coil will run cooler now too, so it'll last a bit longer.

 
thanks mate,

once you sort some of the little problems they get, the PW 's are unstoppable.
give the carby a pull down, and decent clean out, get a new Pilot jet (#50), and work out what Main jet it needs.
then open up the air box a bit.
take the head off, and file/sand 1mm off the face, it'll bump the compression from 6/1, up to close on 10/1.
fit a new spark plug, and some premix at 32/1, and these little bikes will go forever

the rest of the work that i have done to this,
eg stickers and custom exhaust, etc etc, didn't really need doing,
but i can do that sort of thing easily, so i thought why not modifiy it, lol

a mate and his 14 yo son might be taking their bikes up to Acusa park on friday, think we might even tag along....
 
^^ and i see you sussed your signature pic too now.
 
it's too wet here today for the ride day at Acusa, we wer both looking forward to it.


Cj and i have just got home from visiting a couple of mates, they are motor trimmers.
i got a couple of prices for retrimming the PW's seat, i am getting the purplish one done in 2 colours.
the top section is going to be with black gripper vinyl, with blue vinyl sides (he has some nice blue leather too), will cost under $35
and i am going to get the '81 seat redone too later, black gripper top and probably black vinyl sides.

i'm still undecided on respraying the PW50 plastics in IT Blue, or in YZ Competion Yellow ?
 
've been looking at the PW this morning wondering what's next.
i think it might be gettin a new mod soon.
i reckon i can convert to rear twin shock setup to a mono shock setup.
that would make the bike look pretty modern, and keep people guessing too.

now i need to find myself a new gas charged short shock, i wonder what i can find.
thinking maybe something off a mountain bike, like the RST ones i used on the dune buggy, but with a lighter rate spring.
 
i bought a few numbers for the plates too, 50c each from Peter Stevens M/C





ok, found a few different options, some cheap some are big $$$
i will most likely go for a cheapy first, something to suss out the setup, spring rates/length etc.
then eventually i'll buy something that's rebuilable.
there are so many types out the , some of the Cane Creek shocks are around $700 !!


nice used Fox Float-
http://www.ebay.com.au/itm/Fox-Raci..._Parts_Accessories&hash=item1e7cf3d5c0&_uhb=1

a 5th Element-
http://www.ebay.com.au/itm/NICE-5TH..._Parts_Accessories&hash=item58a2126909&_uhb=1

an RST 21, 560lb-
http://www.ebay.com.au/itm/RST-21-M...cling_bikeparts_SR&hash=item257f10c702&_uhb=1

a cheapy-
http://www.ebay.com.au/itm/Mountain...cling_bikeparts_SR&hash=item257f10f439&_uhb=1

a nice narrow internal spring/air Ke Zhen 450lb-
http://www.ebay.com.au/itm/Mountain...pt=AU_Cycling_New_&hash=item1e792b8ccd&_uhb=1

a DNM AO 30R-
http://www.ebay.com.au/itm/DNM-AO-3..._Parts_Accessories&hash=item4174a708c4&_uhb=1

a M-Wave-
http://www.ebay.com.au/itm/DNM-AO-3..._Parts_Accessories&hash=item4174a708c4&_uhb=1



the other day while waiting for the rain to stop i made up a Bar pad using an old pool noodle.
i also remounted the speedo off the back of the front numberplate.





and this is the blue marine vinyl that will be used for the side panels on the new seat cover, shown compared against the blue number plate vinyl sticker.

 
This thread is a great read, keep em coming the monoshock conversion would be epic
 
cheers Zac,
the PW50 rear monoshock idea/conversion has made some progression today.

i have pulled the rear shocks off the bike, and looked at all the mounting points available for a single shock set up.
and i am currently in the process of making up a monoshock rear lower mount,
using the existing r/h front blades' lower mount, and the rear l/h drive tubes' forward mounting points.


i noticed the other day too, when looking at the internets' book of faces,
that our member that no longer visits, the GDFP, Terry has liked my photo of the PW expansion chamber.
i see his son is doing well racing his PW50 too.
he is almost too big for it, and is ready for a bigger bike
 
here is some of the steel i used for the new supsension mounts







a heavy duty shock off a mates pocket bike, unknown spring rate, 200 mm centre to centre.



rear lower mount is 80% made and welded
the original springs are just sitting there to hold the bike up at the moment, the lower mounting bolts are not fitted.





i need to make some plates up to brace the frame for the top mount
then try it out, should be interesting ?
 

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