Chainsaw Repair

Chain - Grinders - Filing - Wood Milling - Tools - Welding - Machinist - Mowers - Tillers => Chain - Bars - Grinders - Filing => Topic started by: Windy_Acres on November 08, 2014, 06:27:57 pm

Title: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Windy_Acres on November 08, 2014, 06:27:57 pm
I picked up an NOS Dolmar 7300 last week. It has a Dolmar 24" bar on it. Id like to buy a 20" and a 28" bar for it.

So I go to the Oregon product selector online, and here is where I get confused, it mentions and 7 and 8 drive sprocket. According to the manual that came with the saw, it has a 7 drive sprocket. I looked at the factory parts list, it only shows a 7 drive sprocket, no other options, and I believe that is the same for the 6400, 7300, and the 7900.

So my confusion is this, does it matter ? Is this 8 drive sprocket a larger diameter, will it affect the size of chain (as far as fit) ? I assume it effects the speed. And if you do run and 8 drive sprocket, where do you get one, is this aftermarket item or an OEM sprocket ?

Looking at the selector, running a 24" bar, as it does in its stock form, its supposed to have an 8 drive sprocket on it now, which according to the owners manual, it does not. I know Oregon is not the last word on how the dolmar saw is setup to run, but still confused.

I looked through this whole sub section of the forum for some info on this topic, so please excuse me if this has been beaten to death in the past, if it has, please direct me in the right direction, and Id be thankful for the direction.

To better understand my confusion, I included "capture" of what I was looking at, please note it calling for an 8 drive sprocket, in the 24" bar ? But then when I move up to 28" it calls for the 7 drive ?

I bought a Oregon 72LGX084G at my local farm store, Im now under the impression that chain is supposed to have an 8 drive sprocket run it ? I just wanted a replacement chain for the stock 24" bar ?

See my confusion ???

Thanks in advance for the enlightenment !
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Cut4fun . on November 08, 2014, 08:14:28 pm
IMO just run a 7. You could run the 8T 16"-20" bars but it will cost you torque which you wont notice on the small bars but will on the longer bars. 8 gives you more chain speed at the cost of giving up torque.
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Windy_Acres on November 08, 2014, 08:21:19 pm
Thanks, so your saying, run the stock 7 drive sprocket on all 3 bars 20" and 28" ? and the chains will all still fit ? As in not too long or too short ?

Thanks !
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Cut4fun . on November 08, 2014, 08:55:02 pm
I would. Chain is same on 7-8
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Cut4fun . on November 08, 2014, 08:56:29 pm
Buy a 7 and 8 and test for yourself on all 3.  Rims are $5 at most.
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Windy_Acres on November 08, 2014, 09:13:19 pm
Okay, got ya thanks.

Off topic, but

 the PMR-30, looks and feels like a toy, due to its plastic and its weight or lack of it. I like mine, I think its allot of fun, but its a PIA to load more than 20 rounds in the clip. Their is a Kel-Tec forum, and I think I read there is a trick, but Ive not really paid much attention to it. Gun is also supposed to stay pretty well lubed to feed well.
Title: Re: Confused on Oregon bars and Chain per their "selector" 7 or 8 drive sproket ?
Post by: Cut4fun . on November 08, 2014, 09:59:01 pm
Okay, got ya thanks.

Off topic, but

 the PMR-30, looks and feels like a toy, due to its plastic and its weight or lack of it. I like mine, I think its allot of fun, but its a PIA to load more than 20 rounds in the clip. Their is a Kel-Tec forum, and I think I read there is a trick, but Ive not really paid much attention to it. Gun is also supposed to stay pretty well lubed to feed well.

Cool Thanks for the info.  Hmmmmmmmm do you need chainsaw for the pmr  ;D :P Hey I tried.