Converting Makita EA4300 to .325 Chain

[501Maico]

Hello all,
I'm close to needing a new 3/8LP chain on my saw and got to thinking about a new bar too. The bar is fine but I don't like the very small radius nose and would prefer something larger. The bar is 16" long but it only has 14" of cut and I want to go with an 18" for 16" of cut and easier ground limbing.
Another option is to change over to a .325 bar and chain. I got a new rim style clutch hub as a spare when I bought the saw so I could convert to .325 with just a purchase of a rim sprocket. My main concern is going from a 6 tooth 3/8 spur to a 7 tooth rim. Am I correct in thinking that this will produce a faster chain speed but less torque? I love how fast this saw cuts with the 3/8LP and don't want to loose that by making a wrong decision. The bars I'm looking at are Oregon SpeedCut or AdvanceCut which are .325 narrow kerf. I think 3/8LP is narrow kerf too.

Please any thoughts or .325 user experience, thanks!

 

[Franny K]

There are 9 tooth nose sprocket bars for that 3/8lp.

Torque is not affected by sprocket size, the tension on the chain and chain speed will vary.

The ratio is pretty close to 8 to 9 or 9 to 8 depending on which way you go. 1640 links per 100 feet for 3/8 and 1848 links for a roll of .325

6 tooth drive brings 3 cutters across a given point per revolution and 7 tooth brings 3 1/2. Normal chain with two drive links per cutter.

The Stihl product 23rspro code 3690 is my favorite of the .325nk chains. There have been some minor changes over time to Husqvarna/Oregon .325nk. Some of the chains seem to dig in and stall out the saw and are amazingly hard to get the chain unstuck. Strange never had this with another out of the box chain. Try it yourself. You could also get a 1/4 inch sprocket, 9 tooth drive, I think; the Stihl 13rm would be strong enough the Oregon 25ap says for 38cc max and is lighter.

 

[501Maico]

There are 9 tooth nose sprocket bars for that 3/8lp.

Torque is not affected by sprocket size, the tension on the chain and chain speed will vary.

The ratio is pretty close to 8 to 9 or 9 to 8 depending on which way you go. 1640 links per 100 feet for 3/8 and 1848 links for a roll of .325

6 tooth drive brings 3 cutters across a given point per revolution and 7 tooth brings 3 1/2. Normal chain with two drive links per cutter.

The Stihl product 23rspro code 3690 is my favorite of the .325nk chains. There have been some minor changes over time to Husqvarna/Oregon .325nk. Some of the chains seem to dig in and stall out the saw and are amazingly hard to get the chain unstuck. Strange never had this with another out of the box chain. Try it yourself. You could also get a 1/4 inch sprocket, 9 tooth drive, I think; the Stihl 13rm would be strong enough the Oregon 25ap says for 38cc max and is lighter.

Thanks for the information. My Stihl chains cut a lot of wood before they need sharpening. Low grade Oregon that came on the Makita is very soft. Stihl, Husqvarna X-cut, or best Oregon I'm thinking on. Do you have a EA4300 running .325 chain?

 

[Franny K]

No, I have the small bore variant the Dolmar 351. The 54 dl loop called 15" is essentially the same bar size as the 16" 56dl 3/8lopro. The 18" 72 dl bar and chain loops would be a good fit. The NK bars are generally thinner and have a 10 tooth nose.

That original equipment soft Oregon chain sharpens really easy. The comparable Stihl chain has more metal.

 

[501Maico]

No, I have the small bore variant the Dolmar 351. The 54 dl loop called 15" is essentially the same bar size as the 16" 56dl 3/8lopro. The 18" 72 dl bar and chain loops would be a good fit. The NK bars are generally thinner and have a 10 tooth nose.

That original equipment soft Oregon chain sharpens really easy. The comparable Stihl chain has more metal.

I looked at the SpeedCut again and missed that it has a lightweight aluminum middle plate. K095 mount so I will need to do the oil modification. Guess I'll try the .325.

 

[John Lyngdal]

I was going to change my EA4300F from 3/8" LP to .325 rim drive, but couldn't identify which clutch drum to install.
I went to the local saw shop and they made me a loop of yellow RS Stihl 3/8" LP chain and it was a noticable improvement in cutting speed and durability.
The diameter of chain drive increases with the spacing between the drive links. For instance a 7 pin 3/8" rim is about the same as a 8 pin .325" rim, so I think going from a 6 pin 3/8" to a 7 pin .325" is reasonable for a EA4300.

 

[esean]

You mean Stihl PS chain? RS is regular 3/8" pitch. PS is 3/8LP.

 

[501Maico]

I was going to change my EA4300F from 3/8" LP to .325 rim drive, but couldn't identify which clutch drum to install.
I went to the local saw shop and they made me a loop of yellow RS Stihl 3/8" LP chain and it was a noticable improvement in cutting speed and durability.
The diameter of chain drive increases with the spacing between the drive links. For instance a 7 pin 3/8" rim is about the same as a 8 pin .325" rim, so I think going from a 6 pin 3/8" to a 7 pin .325" is reasonable for a EA4300.

I like the 3/8LP but I'm having trouble finding a quality 18" bar with a larger nose. I would also like to find a use for my spare rim hub going forward.

 

[Franny K]

I like the 3/8LP but I'm having trouble finding a quality 18" bar with a larger nose. I would also like to find a use for my spare rim hub going forward.

All the Stihl bars for that 0.050-gauge picco 3/8 have 9 tooth noses. They can be converted which involves lenglthening the bar stud slot and drilling a few holes. That will be a 61 drive link for the 6 tooth spur. (3005 mount) There are some obselete GB solid one piece bars (no replaceable nose) that claim to be for 68 drive links but 67 seems sensible for the one I got. Or their new version ones with replaceable noses.

 

[John Lyngdal]

You mean Stihl PS chain? RS is regular 3/8" pitch. PS is 3/8LP.

Yes, I incorrectly used RS as that is the letter code for "regular" Stihl full chisel. I should have stated PS for 3/8" LP Stihl full chisel chain.