Best crank for my Polini.
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- Trafficjamz
- CBR1000RR

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Best crank for my Polini.
Does the polini corsa and a ministroke crank go well together.
Is the SEF crank a better choice?
Or should I just stay with a stock crank.
Is the SEF crank a better choice?
Or should I just stay with a stock crank.
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
Re: Best crank for my Polini.
find a stuffer full counter weighted crank. that way it increases case pressure. thats what you want. so a malossi one or sef stock stroke stuffer.
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90 honda dio sp 72cc
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Re: Best crank for my Polini.
I have this one that I got from zr50 ghost

Is the scorpion pipe a good match for this crank/bore

Is the scorpion pipe a good match for this crank/bore
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
Re: Best crank for my Polini.
yeah that will work good. that one has a longer con rod so use a degree wheel to set the duration.
Nothing like getting stroked!
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
- Trafficjamz
- CBR1000RR

- Posts: 5013
- Joined: Tue Jul 14, 2009 7:53 pm
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Re: Best crank for my Polini.
bakaracer wrote:yeah that will work good. that one has a longer con rod so use a degree wheel to set the duration.
Is the duration is set with extra base gaskets?
Do I need to use polini's metal gaskets.
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
- kingkamehameha
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Re: Best crank for my Polini.
Traffic if you use the scorp try polini yellow or blues and a 2k center. It really likes the high revs. Thats a nice crank you got
ua mau ke 'ea o ka aina i ka pono o hawaii
Re: Best crank for my Polini.
yeah. you will have to get thin gasket paper to make your own. Im not sure if polini has metal base gaskets for the dio. I know they have them for minarelli motors.Trafficjamz wrote:bakaracer wrote:yeah that will work good. that one has a longer con rod so use a degree wheel to set the duration.
Is the duration is set with extra base gaskets?
Do I need to use polini's metal gaskets.
Nothing like getting stroked!
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
- Trafficjamz
- CBR1000RR

- Posts: 5013
- Joined: Tue Jul 14, 2009 7:53 pm
- Location: Eastlake, MI
- Contact:
Re: Best crank for my Polini.
This is the "suicide" crank I got from ZRkingkamehameha wrote:....... It really likes the high revs. Thats a nice crank you got
http://www.hondaspree.net/phpBB3/viewto ... =2&t=20165
I had to fix it.......I hope my fix works.

new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
- Trafficjamz
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Re: Best crank for my Polini.
bakaracer wrote: yeah. you will have to get thin gasket paper to make your own. Im not sure if polini has metal base gaskets for the dio. I know they have them for minarelli motors.
A metal gasket came with the polini kit.
I don't know where to get them individually.
Can the metal ones be stacked like the paper ones?
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
Re: Best crank for my Polini.
yeah. they are very soft aluminum so they crush nice.
Nothing like getting stroked!
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
- kingkamehameha
- CB900F

- Posts: 1005
- Joined: Sat Apr 16, 2011 1:11 pm
- Location: kailua kona
Re: Best crank for my Polini.
Ive been reading over jennings two stroke articles and the degree wheel s*** has me real confused. I need to see someone do it in person or make a video.
ua mau ke 'ea o ka aina i ka pono o hawaii
Re: Best crank for my Polini.
I think you can get metal gaskets with different thicknesses from japan.webike
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Re: Best crank for my Polini.
Yeah, I have seen those.Mystic wrote:I think you can get metal gaskets with different thicknesses from japan.webike
Those are much thicker than I need, and the boost port on a polini is not that large.
What I don't understand is, How the con rod is longer , but the displacement stays the same?
why would this crank need extra base gaskets if it is not a ministroke?
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
Re: Best crank for my Polini.
The stroke is the same but with the longer con rod, it changes the port timing due to rod angle to crank angle.so with a longer rod with the same stroke the port timing will be longer. There is also less stress on the wrist pin and bearing due to less angle on the rod.it also changes blow. Down time because of con rod angle so it stays open a little longer without having to port the cylinder or modifing the ports by adding material
Nothing like getting stroked!
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
Thanks to my sponsors
Nos Energy Drinks,themopedcompany.com,nwautoevents.com,Cycle Gear
90 honda dio sp 72cc
87 elite 50 s with 86cc watercooled mini stroke
87 elite 50 race bike mhr 72cc
91 yamaha tzr 250r
- Trafficjamz
- CBR1000RR

- Posts: 5013
- Joined: Tue Jul 14, 2009 7:53 pm
- Location: Eastlake, MI
- Contact:
Re: Best crank for my Polini.
Will the head or jug need modified the compensate for the jug being raised by extra base gaskets.
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight