Everyones preffered clutch drum type?

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Rim drum or sprocket drum?

  • Rim

    Votes: 26 92.9%
  • Sprocket

    Votes: 2 7.1%
  • Doesn't matter

    Votes: 0 0.0%

  • Total voters
    28
  • Poll closed .

Efisher26

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so I have a craftsman 3.7 that came with what I think is called a "rim sprocket" drum. I found replacements that are the regular sprocket drum. Is there a difference or people preffer one over the other? I may have the name incorrect, please correct me if wrong, thanks!
 

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I love rim/sprocket combination but there is added noise and on some saws it's quite a bit of ringing and clicking till you load the chain.

One huge bonus is better bar and chain life as the rim self aligns so you don't have a chain that trails off to one side and damaging the chain and the tail of the bar and way less jerking of the chain so it lasts longer.
 
Besides saws with outboard clutches... I think its a cost saving measure by the manufacturer to use spur sprockets. A spur sprocket/drum is cheaper than a drum + rim sprocket. However for the end user, when its time to replace the sprocket the rim is MUCH less. Typically the sprocket will wear well before the drum.

For the average homeowner who might never change it, its not a big deal. For the pro, that goes thru lots of chains it would add up quickly.
 
I've found a Oregon replacement rim on eBay for about $6pc. New ones have wear gauges, I'm surprised how these aren't the norm for manufacturers.
 
Also, on my 3.7, the drum is reversed, so the the clutch is visible with the cover off, I'll need to take the drum off regardless... Suck
 
As noted, rim sprockets self-align, and are easier, and less expensive, to replace when worn, or to change tooth count or chain pitch. Most users would choose these if given a choice. Spur sprockets are less expensive to supply with new saws, and often found on consumer saws, that will see less use, and with smaller pitch chains (1/4", 3/8 low profile, etc.). Rim sprockets are not available for all saws or all saw/chain combinations.

http://www.oregonproducts.com/pdf/sprockets/SpurSprocktFB0601.pdf

http://www.oregonproducts.com/pdf/sprockets/RimSproxFB0601.pdf

Philbert
 
I know I figure that, I was surprised companies like Oregon recognize the older saws people are still using, like my 3.7(3700). I have the rim in mine now and will probably keep it that way because u helpful guys Recommend it.
 
The rim sprocket supports the chain load by the chain side plates and the drivers. This "spreading of the load" seems to extend the life of the sprocket. My MS260 is still sporting its factory original rim and the rim is still good even though I have cut a couple hundred ricks of firewood with it. I feel quite certain that a spur sprocket would not have lasted that long. Oh, and I will admit that sprocket is nearing its end of life.
 
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