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Sym dd50 build!!
Posted: Wed Apr 25, 2012 12:04 pm
by Madman
Measured it many times now and it's not growing and it's 48mm every time I measure it, what's funny is that it has 82cc printed on the side of the cylinder, think its wrong don't know why they would bother!!

Re: Sym dd50 build!!
Posted: Wed Apr 25, 2012 3:15 pm
by evilone
Madman wrote:Measured it many times now and it's not growing and it's 48mm every time I measure it, what's funny is that it has 82cc printed on the side of the cylinder, think its wrong don't know why they would bother!!

Looks like it says 82cm to the third to me.
Re: Sym dd50 build!!
Posted: Wed Apr 25, 2012 5:20 pm
by Mystic
CuBiC CeNTiMeTeRs

Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 12:07 am
by veedubh20
evilone wrote:Madman wrote:Measured it many times now and it's not growing and it's 48mm every time I measure it, what's funny is that it has 82cc printed on the side of the cylinder, think its wrong don't know why they would bother!!

Looks like it says 82cm to the third to me.
that is a 50mm bore with stock crank 81cc it is a taiwan bore!
we have the right bore kit has 50mm .
I havent seen a bore kit has smaller piston on 82cc..
that grey base gasket is wrong , you need to get a gasket sheet. trace it and cut.
japanese and chinese are making deals .
Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 12:49 am
by Madman
veedubh20 wrote:evilone wrote:Madman wrote:Measured it many times now and it's not growing and it's 48mm every time I measure it, what's funny is that it has 82cc printed on the side of the cylinder, think its wrong don't know why they would bother!!

Looks like it says 82cm to the third to me.
that is a 50mm bore with stock crank 81cc it is a taiwan bore!
we have the right bore kit has 50mm .
I havent seen a bore kit has smaller piston on 82cc..
that grey base gasket is wrong , you need to get a gasket sheet. trace it and cut.
japanese and chinese are making deals .
Thanks for posting!
But I dont understand, when I measured the bore its 48mm
To my understanding 48mm is a 74cc kit.
I may be wrong, it often happens. please get back to me if you can enlighten me!
Thanks
Luke
Sym dd50 build!!
Posted: Thu Apr 26, 2012 2:10 am
by Madman
The main reason I'm confused is the seller called it a 50mm kit
I also just got a kit from kn kikaku which was also 48 mm and they state that it's 74.? Cc
It's build quality is far better and packaged perfectly I'll have photos up tonight!!
Sym dd50 build!!
Posted: Thu Apr 26, 2012 2:16 am
by Madman
At least the gears look ok and if they work it will make up for the gaskets and BS about the size of the bore!
Compared to original piston!

Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 3:02 am
by paulpauly7
those gears are the same as i got with my cheap as bore kit altho my kit said 82cc and the piston and bore measure 50mm not 48 mm the ports aint that flash they need some work before it gets installed
Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 4:42 am
by tabs808
48mm rounded off with stock stroke is 75cc.
you should calculate those gears to see what they come out to be
49mm rounded off is 80cc
50mm rounded off is 82cc
51mm rounded off is 86cc
thats with stock stroke tho
Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 4:44 am
by paulpauly7
the gears i got are 8.44 to 1
same brand as madmans EXACT
Sym dd50 build!!
Posted: Thu Apr 26, 2012 5:36 am
by Madman
paulpauly7 wrote:those gears are the same as i got with my cheap as bore kit altho my kit said 82cc and the piston and bore measure 50mm not 48 mm the ports aint that flash they need some work before it gets installed
The ports are shocking compared to the kn kikaku one!
Re: Sym dd50 build!!
Posted: Thu Apr 26, 2012 5:53 am
by paulpauly7
night and day to a corsa
Sym dd50 build!!
Posted: Thu Apr 26, 2012 6:08 am
by Madman
The gears are 15 , 42. I think or 16, 42!
Sym dd50 build!!
Posted: Thu Apr 26, 2012 6:12 am
by Madman
Found this on another thread
DD50
15x42=10.9 7.93to1
16x42=10.2 7.43to1
17x41=9.44 6.83to1
18x39=8.4861 6.13to1
19x38=7.8333 5.66to1
VS.
Elite S
15x41=9.8
16x42=9.18
17x41=8.44
18x39=7.58
19x38=7.0
Sym dd50 build!!
Posted: Thu Apr 26, 2012 6:21 am
by Madman
I'm gonna go with the kn kikaku BBK it's 75cc that should be enough to be happy I guess,if not I'll get 50 mm kit in the future!! I'll keep this bore for a back up as its the exact same size as the kn bore 48mm or find somewhere to bore it out to 50mm but it may be cheaper just to buy one later!!
I'm gonna start the build tonight as I have all the required parts and any others like new hoses or clamps I can pick up at drivers stand 2rinkan. = bike shop in Japanese!!