ms 261 8 tooth sprocket

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Anyone know where I can get an 8z picco rim please? Mini spline. Nup, I ain't joking, just really want to learn by trying.

Or, is there such a beast as an 8z .404 mini-spline (or step-down adapter to get it back down to mini spline) rim that someone has turned down to suit picco chain?

Because looking for needles in a haystack is fun, right?
 
Iv'e just installed a 8 on my 261 cm with a 3/8 set up 18" bar. I'm running full skip rmf chain. With the exhaust mod. This saw really performs well over the stock set up. It now clears the chips very well and no pinching . I thought It would bog for sure, but the saw has great torque. The full chain was a okay the 8 but would have been much better with a 7. going to the skip chain with the 8 made it so you could even push into the wood without bogging the saw at all. Just to compare I have a 7 pin coming to try with both chains next week. No other mods as of yet.
What your created is a recipe for blunt chains, really quickly. This may not be an issue in the wood you cut.
Skip gets dull faster than full comp, less cutters doing the work.
Increased chain speed dulls chains faster.

You've got the double whammy - everything has a downside.
 
So today I received my 7 pin and rushed out to see how it would perform. For those just tuning in I'm running a 261cm exhaust mod, 18"bar, 8rim with full skip 3/8 chain and really like it. I ordered a 7 rim to compare with the 8 rim. My test tonight was quick and simple slam on the 7 and get in the big spruce laying on the front lawn then try the 8.

the motor was working harder under the load to keep digging very torquey feel. I felt a slightly more subtle digging motion in the saw as it cut. I felt like I was working more as well. All in all the 7 did just fine and cut well. I questioned the sensation of working harder so I put the 8 to work. No doubt it cut faster and I felt less exertion I like this set up a margin better for what I'm doing with the saw. I think the 7 would be better on a 20" inch bar or with a more aggressive chain. One person commented the chain wear would be more substantial with the set up I like. This made sense but have not yet had the time on these chains to see how they play out with one another. At least the full skip will be quick to sharpen. LOL! lazy man talking. Thanks for all your input fella's and please remember I did mod my exhaust so this information would not pertain to those who didn't have a exhaust mod. If I get the time I'll do a video of the two with times in some harder wood. And yes I did run both in oak with similar results.
 
It never ceases to amaze me how many operators recommend 8-pin rims, especially after they bought one to replace the 7-pin that Stihl supplied with the saw. I wonder what they would say if somebody gave them the 8-pin rim for free.

An 8-pin rim is going to require more torque while delivering more speed to the chain. Assuming there is enough horsepower to deliver the torque required, you might cut faster. If there is not, then you will not cut faster.
 
l am running a 9pin .325 drive sprocket on a stock 555at husky with a 15" 58dl windsor speed tip bar. lts a hoot on sub 14" wood!! Have l got something wrong?:surprised3:

It looks like a bit much - but if you like it, there is no reason to not do it.

Lots of factors are involved, and no answers are carved in stone.

I really liked using 3/8"x8 on my Euro MS361, for limbing and "light" bucking, also with a 15" bar. :D
 
It never ceases to amaze me how many operators recommend 8-pin rims, especially after they bought one to replace the 7-pin that Stihl supplied with the saw. I wonder what they would say if somebody gave them the 8-pin rim for free.

An 8-pin rim is going to require more torque while delivering more speed to the chain. Assuming there is enough horsepower to deliver the torque required, you might cut faster. If there is not, then you will not cut faster.

It certainly takes more torque to keep the rpm and chain speed up, so it is a fine balance. The 13% or so gain in chain speed is soon lost if the rpm isn't kept up.
 
It never ceases to amaze me how many operators recommend 8-pin rims, especially after they bought one to replace the 7-pin that Stihl supplied with the saw. I wonder what they would say if somebody gave them the 8-pin rim for free.

An 8-pin rim is going to require more torque while delivering more speed to the chain. Assuming there is enough horsepower to deliver the torque required, you might cut faster. If there is not, then you will not cut faster.
It never ceases to amaze me how many operators recommend 8-pin rims, especially after they bought one to replace the 7-pin that Stihl supplied with the saw. I wonder what they would say if somebody gave them the 8-pin rim for free.

An 8-pin rim is going to require more torque while delivering more speed to the chain. Assuming there is enough horsepower to deliver the torque required, you might cut faster. If there is not, then you will not cut faster.[/QU_OTE]

This is what this operator did say. Did you read my entire postings? No. Didn't think so.... One more time the FREE 8 given to me out cuts the 7 in speed and no bog buried in the wood. I then paid $$ to get the 7 after more positive comments were given. I will wear out both set ups for sure! RECAP... I changed over from the "supplied" .325- 7 to a 3/8. because it didn't clear chips well enough for me pinching the chain in the bar often enough. No more problem with the 3/8 and I happen to like both rims but slightly prefer the 8 so far for my cutting. The 261cm can handle it no problem with the exhaust opened up and skip.
 
So today I received my 7 pin and rushed out to see how it would perform. For those just tuning in I'm running a 261cm exhaust mod, 18"bar, 8rim with full skip 3/8 chain and really like it. I ordered a 7 rim to compare with the 8 rim. My test tonight was quick and simple slam on the 7 and get in the big spruce laying on the front lawn then try the 8.

the motor was working harder under the load to keep digging very torquey feel. I felt a slightly more subtle digging motion in the saw as it cut. I felt like I was working more as well. All in all the 7 did just fine and cut well. I questioned the sensation of working harder so I put the 8 to work. No doubt it cut faster and I felt less exertion I like this set up a margin better for what I'm doing with the saw. I think the 7 would be better on a 20" inch bar or with a more aggressive chain. One person commented the chain wear would be more substantial with the set up I like. This made sense but have not yet had the time on these chains to see how they play out with one another. At least the full skip will be quick to sharpen. LOL! lazy man talking. Thanks for all your input fella's and please remember I did mod my exhaust so this information would not pertain to those who didn't have a exhaust mod. If I get the time I'll do a video of the two with times in some harder wood. And yes I did run both in oak with similar results.

I'd love to see a video of this 8 pin 3/8" cutting faster on a 261. I have a 261 and have tried every variation of .325, .375, and lo pro... 8 pin 3/8" has no business on a 50 cc saw.
 
This is just a 3/8" 7T against a lo pro 7T. The 3/8" 8T is sad in comparison. As other stated. Unless it's a BIG saw. 8T doesn't help..

You do not need a stop watch for this...



 
I'd love to see a video of this 8 pin 3/8" cutting faster on a 261. I have a 261 and have tried every variation of .325, .375, and lo pro... 8 pin 3/8" has no business on a 50 cc saw.

Video? LOL.... As i said, I haven't even timed trialed any of this yet. My experience with all this is feel at this point. I get it. I know the saw is 50.5 HP and I've put more load and rim to it. It needs power to maintain the rpm to run this large sprocket . I'm not trying to insult anyone or claim the 8 is a clear deal for this saw. I just like the way the saw feels and cuts, in the short term testing This set up was not intentionally. The rim was given to me a with some other stuff. The verdict is out on chain wear. I'm just messing around after working full time and have limited time for this and videos. Next time out I'll get someone to time them . If the 8 is still faster Ill try to get a video of it. It may be that the 8 feels faster or better in the hand I don't really know for certain yet.

Dexter,
Whats set up did you settle on after all your testing of chains? Is your saw stock?
Thanks
 
I hear a 8 tooth FEELS faster a lot, take out the stop watch with the same brand new chain and keep the saw at the peak HP rpm and report back, if you are one that lets the saw scream the 8 will cut faster than a 7 but not when the saw is kept at the right rpm. Steve
 
OTW (off the wall?) is using full skip. I am not sure everyone has noticed that. Pretty sure 18" bar is shorter than the chain manufacturers recommend for skip chain probably for safety reasons at the top of that.
Hey Franny, Thanks for your input. I had never heard of this but thought for safety of it all I had better double check.
This is copied off the Stihl website. It says it can be used on short bars as well. I keep chain short so the bar is close to the rim. I thought the chain might pinch and throw otherwise. Its a pain to get the chain on but it seems to work.

STIHL RAPID™ Super Full Skip is the skip-pattern version of STIHL RAPID™ Super. There is an extra drive link and tie straps between each cutter, allowing better chip discharge and higher chain speed. The RSF chain is an extremely fast-cutting chain. The razor-edged, square-cornered cutter shape ensures minimum chain friction for an exceptionally smooth and clean cut in hard or frozen wood. It offers excellent cutting and plunge-cutting efficiency. Since there aren’t as many cutters, RSF chain reduces the amount of time needed for sharpening. RSF chain typically cuts faster than RM chain, but requires careful maintenance and sharpening to continue to perform well. It is especially suited for long bars on large diameter logs, but can be used on short bars as well.
 
OTW (off the wall?) is using full skip. I am not sure everyone has noticed that. Pretty sure 18" bar is shorter than the chain manufacturers recommend for skip chain probably for safety reasons at the top of that.[/QUOTE

OTW ....Off To Work! )
 

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