Rim sprocket conversion

[jeff_t]

Will this let me get rid of the spur, and put a rim sprocket on it? http://www.ebay.com/itm/19071596932...sacat=0&_nkw=190715969326&_rdc=1#ht_500wt_986

It's an older MS270C, around 2004 I think. I read in one of the other listings that older models have a notch in the drum to drive the oil pump, or something like that.

 

[Danno77]

I think that should work, but i don't have firsthand knowledge. That drum should have the little notch and worst case scenario you'd have to grab a file and make one yourself.

 

[Danno77]

why the conversion? just cause, or you have some chains you want to be able to swap from saw to saw?

 

[jeff_t]

Why? The spur is really worn out. The cost isn't that much more to put a rim sprocket on, and that kit above also has a new bearing.

 

[MasterMech]

I'm a big believer in converting to rim sprockets once the spur sprocket is done. I've done my BIL's MS250 and other small saws as well. It just makes sense $$-wise. Then from here on, you need only replace a relatively cheap rim sprocket every once in awhile, and the rims don't wear as fast as the spurs.

 

[Danno77]

I don't disagree, I just wondered if he was replacing for another reason. Although, my 028 has the original spur on it and looks just fine. How much cutting you gotta do to wear one out?

 

[bogydave]

I don't disagree, I just wondered if he was replacing for another reason. Although, my 028 has the original spur on it and looks just fine. How much cutting you gotta do to wear one out?

No set "how much"
dirt , loose chain etc can wear it out quicker.

I'm a big believer in converting to rim sprockets once the spur sprocket is done. . It just makes sense $$-wise. Then from here on, you need only replace a relatively cheap rim sprocket every once in awhile, and the rims don't wear as fast as the spurs.

+1

 

[jeff_t]

No set "how much"
dirt , loose chain etc can wear it out quicker.

I got it cheap from a golf course. It likely wasn't operated by the sharpest individuals.

I already know I'm going to do it. I was just wondering if that kit above is all that is necessary, or if there was something else I needed to look for.

 

[n6crv]

That is all you need but be sure you are runnig the .325 chain.

 

[Nixon]

You might want to get a few extra "E" clips. Seems like once they get even 1 mm clear of the crank shaft the can become invisible ! At that point they are even called by a different name . Having more than one on hand cuts down on the odds of this happening .

 

[kevin j]

Other pluses:
-Flip the rim around and get another life out of it (although for $5, they are consumables.)
-Mentally easier to justify throwing on a new rim more often than to change ann expensive spur and dru
-Less chance of chain derailing say with different chain or differenty bar. As a spur wears, the chain drivers have to follow that exact wear pattern, which may differ slightly from the path the chain would like to take. The spur floats back and forth on the splines as necessary
-Ability to change the gearing ratio, when changing bar size. I run a 8T with 20 bar on the Dolkita, 7T with 28 or larger bar.
-Yes, buy several extra E clips and cup washers for the end of the crankshaft. Changing the sprocket in the field often sends the E clips zinging off. Odds are directly proportional to how important the saw is for the day......

 

[MasterMech]

For hose e-clips, twist a flat-head screwdriver in the opening of the clip to remove it. But make sure you're hand is covering it or drop a rag around it and that clip will wind up right where you need it to be, within easy reach.

kevinj made some excellent points on why the rim over a spur sprocket. Chain speed adjustments via sprocket gearing (for those of us that insist on running 70+cc saws with 20" bars or smaller.... ) and the way the rim "floats" on the spline hub are biggies.

 

[jeff_t]

Thanks all, for the info. I've had this saw for a couple of years, and haven't really messed with it. I like it a lot better since I put a 16" bar and yellow chain on it. I used it a while last summer when I was in and out of a loader, cutting logs off, as it was handier than my bigger Dolmars. Then it quit shutting off with the switch, and has been sitting in the garage since. I got that problem fixed, and I'll replace the sprocket and use it some. It'll be my loaner saw, too.