Nik's Poulan Thread

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What do you guys think of running 8 pin 3/8 rims vs 7 pin rims on 75cc+ saws considering I'm only using 20 - 24 " bars?

Sounds like a really good idea to me. Any down side to this? I'm thinking of the 5200 and the Pioneer P51 (82CC)

Both saws will pull a 8 just fine with those bars. A 3/8's X 8 is close in dia to a .404 X 7 and both of those saws were used with .404.

I really dont think you will see a big difference in the real world though. Try it and see.
 
What do you guys think of running 8 pin 3/8 rims vs 7 pin rims on 75cc+ saws considering I'm only using 20 - 24 " bars?

Sounds like a really good idea to me. Any down side to this? I'm thinking of the 5200 and the Pioneer P51 (82CC)



I think that you will see a 15% increase in out of the wood chain speed and a 15% decrease in power.
You probably won't see a 15% increase in cutting speed (maybe more, maybe less) depending on how your chain is "tuned".
The same chain will not cut the same at 5500 feet per minute as it will at 5000 feet per minute.
The 15% reduction in torque is not really a true measure either as friction will be higher at higher speeds.

It is kind of like a golf game. It can never be mastered. the minute you think you've got it perfect one of the many factors will change and the hunt for the right combination is on again.

Rims are cheap, try it and see what you like best.


Mike
 
Got him working right.

The bearing inner race being .008" longer made the difference. Chain stops at idle now. I did tap the crank/oiler seal in a bit (.005-.010) for good measure.

I bet 10 USD to a donut that the nominal length of the Torrington inner race should be 17/32" or .5312".

He runs stronger on each cookie it seems.

Rustolium 'Lemon Grass' wasn't a good match for the early Poulan yellow/green but it was the only game in town.

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My question would be "Why?" unless you're in a race. I'm sure the saw will pull that on a shorter bar but I think you also increase the chance of collateral damage to the saw and maybe yourself if you throw a chain.

Why? becasue I like to fiddle with my saws. The Homelite XL-902 (77cc) has an 8 pin spur on it and it cuts very well with it (when it's running as I have work to do on it).
I can't see where an 8 pin on these saws will hurt anything or cause them to throw a chain.

Both saws will pull a 8 just fine with those bars. A 3/8's X 8 is close in dia to a .404 X 7 and both of those saws were used with .404.

I really dont think you will see a big difference in the real world though. Try it and see.

I think that you will see a 15% increase in out of the wood chain speed and a 15% decrease in power.
You probably won't see a 15% increase in cutting speed (maybe more, maybe less) depending on how your chain is "tuned".
The same chain will not cut the same at 5500 feet per minute as it will at 5000 feet per minute.
The 15% reduction in torque is not really a true measure either as friction will be higher at higher speeds.

It is kind of like a golf game. It can never be mastered. the minute you think you've got it perfect one of the many factors will change and the hunt for the right combination is on again.

Rims are cheap, try it and see what you like best.


Mike

I have ordered a rim to see what the diff is. I've ordered some NLA stuff with it as well so I likley won't see the rim for a while.

Tim
 
What do you guys think of running 8 pin 3/8 rims vs 7 pin rims on 75cc+ saws considering I'm only using 20 - 24 " bars?

Sounds like a really good idea to me. Any down side to this? I'm thinking of the 5200 and the Pioneer P51 (82CC)

I would use a 8 pin on any 5 cube Poulan with a 24 inch bar as the saw will have plenty of torque to pull it easily, with operating RPM's in the high 7000 these are big torque saws able to pull long bars and big chain. I use a 8 pin on my 2 8500's and have pulled a 28 with ease and enough power that when a linear kickback occurred the saw came completely out of the cut with a 24 inch bar buried.
 
I'm sure the saw will pull that on a shorter bar but I think you also increase the chance of collateral damage to the saw and maybe yourself if you throw a chain.


I can't see where an 8 pin on these saws will hurt anything or cause them to throw a chain.

I have ordered a rim to see what the diff is. I've ordered some NLA stuff with it as well so I likley won't see the rim for a while.

Tim

My post didn't say an 8 pin would "cause them to throw a chain." It said that you might increase the chance of damage "if you throw a chain."
 
Well it looks like I'll be building another of my Poulan 330 "Supers". I bought a cylinder and piston a couple of weeks ago and tonight bought what looks to be a fairly clean 330 with low compression (at least advertised that way). I hope this one goes faster than the 5020 project still in the tub apart.

This will be the first saw that I cut the squish band on and we are going to see just how much one of these can put out. If everything goes well I think I'll sell the first one I did (if this one will run like I think it will).

Poulan Pro 330 Chainsaw for Parts not Runnig | eBay
 
I use a 8 pin on my 2 8500's and have pulled a 28 with ease and enough power that when a linear kickback occurred the saw came completely out of the cut with a 24 inch bar buried.[/QUOTE]

That would definitely wake you up.
 
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I use a 8 pin on my 2 8500's and have pulled a 28 with ease and enough power that when a linear kickback occurred the saw came completely out of the cut with a 24 inch bar buried.

That would definitely wake you up.[/QUOTE]

It came out with some speed, I have had a log pinch a saw before while bucking but usually it will just get stuck until I can drive a wedge, so lets just say I am impressed with the torque of these Poulans.
 
Well it looks like I'll be building another of my Poulan 330 "Supers". I bought a cylinder and piston a couple of weeks ago and tonight bought what looks to be a fairly clean 330 with low compression (at least advertised that way). I hope this one goes faster than the 5020 project still in the tub apart.

This will be the first saw that I cut the squish band on and we are going to see just how much one of these can put out. If everything goes well I think I'll sell the first one I did (if this one will run like I think it will).

Poulan Pro 330 Chainsaw for Parts not Runnig | eBay

Are you going to take some pictures and post some numbers of the timing and what kind of compression you end up with. Also are you going to advance the timing? Just interested.
 
Are you going to take some pictures and post some numbers of the timing and what kind of compression you end up with. Also are you going to advance the timing? Just interested.

I can post pictures and timing numbers, YES on advancing the timing as I think that improves this series in stock form. I'll be shooting for compression in the 190+ range. The one I have has 180 with a pop up piston.
 
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