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parrisw

parrisw

Tree Freak
Joined
Jan 18, 2007
Messages
13,786
Location
British Columbia, Canada
Heh heh. I'm seriously seeing numbers on the inside of my eyelids at the moment. Adding a few more would be disastrous :)
Go nuts though mate and I'll be here in the background lurking. Got the HD filter kit yet? :cheers:

Yup, I'm going. This dang Christmas thing is slowing me down, here with the kids now, putting up the tree, lights, decorations, ect ect......

HD filter kit will be here soon, should be here this week.
 
timberwolf

timberwolf

Addicted to ArboristSite
Joined
Aug 29, 2002
Messages
3,801
Location
Ontario
The staggered transfers can be good, lots of different stratigies, but often the rears are a little higher and pointed up a bit, the fronts are low accross the and later opening. This way the two sets of transfers are not fighting to fill the same part of the cylinder.
 
parrisw

parrisw

Tree Freak
Joined
Jan 18, 2007
Messages
13,786
Location
British Columbia, Canada
The staggered transfers can be good, lots of different stratigies, but often the rears are a little higher and pointed up a bit, the fronts are low accross the and later opening. This way the two sets of transfers are not fighting to fill the same part of the cylinder.

Thanks TW. I couldn't see the set closest to the intake, I was looking through the plug hole, and could only see the ex side ones. I'll know when I stick a ring down there and look at it.
 

MCW

Somebody's talking crap here & it ain't the tree!
Joined
Sep 10, 2008
Messages
13,351
Location
Riverland, South Australia
Righteo then.
Was on the phone to Al before who wondered if a Stihl 460BB piston may fit the Dolmar BB kit to gain a wider skirt - firstly yes it is wider! Funnily enough I have a 460BB kit sitting here! Have just taken a few measurements for those curious parties...
Piston pin is the same diameter and a nice fit as is the 460BB piston in the 7900BB bore.

Anyways, here they be...

DSCF1442.jpg


Measurement 1 is : 15.68mm (0.617")

Measurement 2 is : 13.60mm (0.535")

DSCF1441.jpg


Measurement 3 is : 36.00mm (1.417")

Measurement 4 is : 32.02mm (1.261")

Measurement 5 is : 33.94mm (1.336")

***The two different Dolmar BB skirt measurements are given due to a step in the piston skirt. Not sure what measurements guys may want.

If anyone wants other measurements taken I most certainly can. I haven't got anything other than a good set of metric calipers but they are quite accurate.

Hope that helps and as you can tell I am very proficient in the use of Microsoft Paint, not... :cheers:
 
Last edited:
parrisw

parrisw

Tree Freak
Joined
Jan 18, 2007
Messages
13,786
Location
British Columbia, Canada
Righteo then.
Was on the phone to Al before who wondered if a Stihl 460BB piston may fit the Dolmar BB kit to gain a wider skirt - firstly yes it is wider! Funnily enough I have a 460BB kit sitting here! Have just taken a few measurements for those curious parties...
Piston pin is the same diameter and a nice fit as is the 460BB piston in the 7900BB bore.

Anyways, here they be...

DSCF1442.jpg


Measurement 1 is : 15.68mm (0.617")

Measurement 2 is : 13.60mm (0.535")

DSCF1441.jpg


Measurement 3 is : 36.00mm (1.417")

Measurement 4 is : 32.02mm (1.261")

Measurement 5 is : 33.94mm (1.336")

***The two different Dolmar BB skirt measurements are given due to a step in the piston skirt. Not sure what measurements guys may want.

If anyone wants other measurements taken I most certainly can. I haven't got anything other than a good set of metric calipers but they are quite accurate.

Hope that helps and as you can tell I am very proficient in the use of Microsoft Paint, not... :cheers:

WOW!!! That's awesome!! Much easier swap then the 288 piston!! I may have to order up one of them pistons from Baileys! That step in the skirt is wierd Matt?? Mine here doesn't have that.
 

MCW

Somebody's talking crap here & it ain't the tree!
Joined
Sep 10, 2008
Messages
13,351
Location
Riverland, South Australia
Matt dropped off the Makita 6401BB today,(thanks Matt) I didn't do any cutting with it today
(too hot over 100F) but I did start it, the compression & throttle response is amazing. My previous newest saw is 1990.. running this one will be a real treat.
Will, I hope you get good results from your BB kit, hopefully these kits will be reliable.

Hey remember Wayne that saw has been given a hiding and locked in a shed. It is meant to have caked on sawdust and oil on it. If I ever see it so shiny that you can see your face in it I'm stealing it back in a midnight ninja raid...

Enjoy it mate, they're a good saw and if you do ever have any dramas with that kit let me know and I'll sort it out for you :cheers:
 
parrisw

parrisw

Tree Freak
Joined
Jan 18, 2007
Messages
13,786
Location
British Columbia, Canada
Neither do my other BB pistons I have here ;)
Yeah will the deck height (or whatever you techy guys call it!) be an issue Will?

OH ya, ha ha. Guess I got excited about it. Well, ya it looks like it might be an issue, espicially since I've already decked the cylinder base.:cry:

Its possible it could be made to work, if you don't deck the cylinder and make it into a popup piston.
 
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