7,8,9T Sprockets

[Aled Hughes]

Hi all, can you experts explain to me advantages/disadvantages of the above sprocket sizes as in my head as a biker im thinking smaller gearbox sprocket more bottom end and bigger more top end speed if the engine has enough power to pull it, then i suppose the length of bar comes into the equation. Usual saws used 346xp 15" 560,562xp 15+18"  thanks 

[Stubby]

5 minutes ago, Aled Hughes said:

Hi all, can you experts explain to me advantages/disadvantages of the above sprocket sizes as in my head as a biker im thinking smaller gearbox sprocket more bottom end and bigger more top end speed if the engine has enough power to pull it, then i suppose the length of bar comes into the equation. Usual saws used 346xp 15" 560,562xp 15+18"  thanks 

Yes you are pretty much right . Most saws seem to come as standard with a 7 pin . All my saws are ported so , dependent on bar lenght they can run a 9,8 or standard 7 pin . For example my ported 560 with a 18" bar will pull really well with an 8 pin . my ported 372 has a 24" bar and I find it better on a 7 pin . For any given bar lenght the faster the chain speed  ( 8 or 9 pin )the less torque you have . There is a sweet spot and you will find it when you cut wood . Another thing to consider is a standard chain loop will accommodate an 8 pin over a standard 7 pin but will need another driver link  in it fi you go above that .

[adw]

I hate to be a kill joy but increased chain speed will start to require class 2/3 trousers, just saying not looking for an argument.

[pleasant]

1 hour ago, adw said:

I hate to be a kill joy but increased chain speed will start to require class 2/3 trousers, just saying not looking for an argument.

Yup...it will just take a bit longer to get down to the bone wearing that class. 😁