Rim vs Spur Sprocket

I just bought a Husqvarna 55 from another member here. I have a couple different bars I want to try out on it. It's shipping with an 18" .325 sprocket and bar. I also have a 20" 3/8 bar that I'd like to try running, and compare power and cutting speed and decide what I like.

So I'll need another sprocket. I'm not sure whether this saw has a rim or spur sprocket yet - it will be arriving next week. I like the rim-style sprocket that's on my 385, because it makes changeover so easy. But the 55 has an outboard clutch, so the entire hub always needs to come off to change it, whether it's rim or spur.

That being the case, my question is, would the spur type be more durable than a rim? If it is, maybe I'll go with one of those. Maybe I could save a couple bucks today if I only need to buy a 3/8 rim sprocket, but since the entire hub has to come off anyway, maybe I'll go with the spur if it will last considerably longer.

 

No the spur drive isn't going to last longer and it will cost you more than rim sprockets will over the lif of the saw.

 

I changed from spur to rim a couple years ago wondering the same thing. Very easy, and I like the rim better. Seems to be wearing better.
Changing from 20"/3/8 to 18"/.325 makes it a little nicer to run. Cuts a little quicker and I like the balance better.
Might be the "butt dyno" effect, but it feels a touch lighter as well.

 

+1

 

We need to look at the economy of the situation.
You've got a 18" .325 on the way . . . You need to use it or sell it?
The 455 normally comes with a spur sprocket . . .

 

Oh her cookie cutting, shelf queen days are numbered... I'll be putting this baby right to work! So I don't mind spending a few bucks on it playing around with different bars/chains.

I am expecting it to have the spur. Hopefully it already has a rim, then I don't need an entire new assembly to test out the 3/8 and possibly end up disappointed. Sounds like the rim sprocket and hub will be the way to go if it does need changing.

 

I like it with the 18" .325

 

Though it is not directly cross referenced, the diameter of the clutch itself and of the bearing is the same on the 346, 350, 357, 455.

The clutches themselves have different part numbers because the 455 has U-shaped springs and the 357 has coil springs to retain the clutch shoes.

http://www.ebay.com/itm/HUSQVARNA-C...834?pt=LH_DefaultDomain_0&hash=item51c8512802

 

There's another potential problem. The oil pump drive worm is driven from the face of the clutch drum. A spur and a rim drum have a different pattern on the face that mates with the oil pump worm gear.

From my experience the same worm will work with either clutch bell but If there were prior events that damaged the worm or the worm doesn't work for some reason, you know where to look? There is a indented pattern on the face of the worm that supposed to mate with the face of the clutch bell hub.

I run a 357 clutch bell on my 346 with the larger diameter rim and it works fine with the original worm. The original clutch bell had a small pattern rim whereas the 357 has a large pattern rim and this must mate with the worm gear for the oil pump to work.

 

Hmm - I watched a Youtube video, and it made it look easy! May need you fella's help finding the right part when the time comes.

I only vaguely understand what you're saying. The sort of questions I was thinking about asking were more on the level of: "which is the bigger cutter - .325, or 3/8LP"?

 

all the 55's I've had rim type clutch drums. your original post said 55, not 455, I don't think i've ever seen a 55 spur sprocket. when they sold both the 55 and 55 rancher, the main difference was 3/8 chain on the later years of the rancher and the dealer would swap rims out to match bars and chains.

Edit: I'm not saying they didn't make one, or someone didn't put an Oregon spur on at some point in time. I've owned about a dozen 55's over the years and can't recal ever seeing one with a spur.

 

That's good news to me. Care to weigh in with your bar/chain preference?

 

I miss-read the original post and though it said "55", I was thinking "455"

 

when it was my small saw, I used it with a 3/8 and 16". muffler modding will help. I had an 18" on it at one time, but liked it better with the 16" for limbing and balancing. I've never been a fan of .325 for firewood duties. 3/8 chain always seemed to stay sharper. a 20" in 3/8 chain might be too much unless you mod the muff and retune. I never went crazy with bar length because if I needed a longer bar, I used my 365/372 with a 20 or 24".

If I had to run a 20" on it, I'd probably run it with .325.

 

The 55's have a full time oiler and the worm is a interference fit on the crankshaft?

It is not driven by the clutch hub or has any relationship with it.

The worm gear has to be removed with a puller and applied with a drive collar.

 

That Husky 55 uses a rim sprocket and does just fine with 3/8" on a 16" bar. Which is better? That's your call. Either way I think it's best suited to sport a 16" bar but capable of running 20" as necessary. I agree in the longer bar sizes, .325 would probably be best.

 

Heres a question. I have a 262xp with brass worm drive on crankshaft thats continuous oiling. Can I buy the newer 262xp plastic worm gear kit thats clutch activated that will work on my 262?

 

I've done this on a Dolmar.
It takes close examination of the differences and how the oiler drive works with each system.
Sometimes it is difficult to ferret out what's needed?
Sometimes Ebay pictures help? Sometimes the sellers on Ebay are full of crap, not correct, or maybe even act dumb or don't actually know?
One thing for sure, you will need to disassemble your 262 enough to see and understand every part of the oiler drive and why it was there.
Compare these parts with what's on the IPL's so you know for sure what you need. Look at the different dates of the IPL's?

In my case with the Dolmar, I needed a certain shape on the clutch hub that was not documented anywhere to mate with the worm gear and drive it. This special shape was not documented anywhere and I just happened to see it on Ebay one day. This made all the thoughts come together and make sense for the oil pump drive to only work with the clutch bell or hub.

The workshop manuals are usually made when the saw was first introduced and with changes in the saw design the workshop manuals are not updated. Also as the saw evolves the pictures in the IPL's are not necessarily updated.

I've had saws with full time oilers and actually at idle the pump doesn't put out much oil. So even though the part time oiler is a EPA thing to save oil being wasted into environment, there's really not a tremendous difference between full time and clutch bell driven oiling systems in the overall amount of oil put onto the ground.

Out in the woods, the 262 was one of the best firewood felling and blocking saws ever made right in there with the 036. Though I admire them, I do not own one.

Looking at the IPL's You will need to pull the existing steel worm.
Remove the large diameter washer that keeps the rim sprocket on the clutch hub.
Install a plastic clutch worm which includes the built on washer.
Put everything back together. See if it works???

There are other unknowns in that the two clutch bells have different part #'s but I don't know the differences? The bearing may be different OD is the difference?

Do you have the IPL parts lists for your saw and for the 1999-06 (262) saw that you can download from the Husqvarna support site?

 

Yes I have them. It looks like I can delete the press on worm gear and the washer and install the plastic worm gear that replaces the sprocket keeper and also the clutch drum needs to be replaced also because the old style drum doesnt have the 4 splines that engage the new plastic worm gear