Question about Stihl chain length

[kennyz]

Stihl MS261c and MS251c both run an 18" bar with .325 chain. Why does the 261 run more links (74) than the 251 (68) ?

 

[Van462]

They use different bar patterns. The 251 has a single bar mounting nut vs the 2 on the 261. If I remember right the 251 uses bars with 3005 part numbers and the 261 3004 part numbers. The single nut bars usually have a bar with an open end and mount very close to the spur/sprocket. Where the double nut style have a closed rear and mount a bit further out.

 

[HarleyT]

Bar studs are a different diameter too,

in case you are wondering.

 

[Wood Doctor]

The 18" bar for a Stihl 025/250/251 is about the same length as a 16" bar for an 026/ 260/ 261. Two company divisions out of synch. Happens all the time.

 

[Ryan'smilling]

They use different bar patterns. The 251 has a single bar mounting nut vs the 2 on the 261. If I remember right the 251 uses bars with 3005 part numbers and the 261 3004 part numbers. The single nut bars usually have a bar with an open end and mount very close to the spur/sprocket. Where the double nut style have a closed rear and mount a bit further out.

Pretty close. It's 3005 mount for the small saws, 3003 for the large ones.