Roll Tide
Trolltide
Never looked at it like that.
Stihl MS 661 32" bar size maximum?
- Thread starter tamarack56
- Start date
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HuskStihl
Chairin'em for the sound
The 0.063 is a ***** to sharpen tho. Had to buy heavy duty files.
Haywire Haywood
Fiscal Conservative Social Retard
I can count on both hands the amount of times I've needed to run the 36" bars I've had, so I'll accept it. Still doesn't make any sense to me though. LOL The 36" bar I have for that 395 in my sig is a 50.
Can you put more stuff into a .013" wider groove? More space for oil if the oiler can feed it to carry it around the bar.
The 36" .050" is used for people who want the same chains for all lengths.
Haywire Haywood
Fiscal Conservative Social Retard
I doubt most oil pumps are filling all the gaps in the chain to capacity, so I doubt the extra space is actually used. Like I said though, if it works it works, I don't have to understand it.
Chris-PA
Where the Wild Things Are
Since there are gaps between the drivers a wider groove will be able to carry a larger volume of oil to the end of the bar - but compared to the volume of oil coming out of the pump it's hard to imagine the bar would be a limitation even at 0.050".
Just picturing the space between the drivers and the gap from the tip of each driver to the bottom of the groove at 0.050" - if that is what is limiting the flow of oil, how long would it take to pump the tank dry? 5seconds maybe? 10?
Just picturing the space between the drivers and the gap from the tip of each driver to the bottom of the groove at 0.050" - if that is what is limiting the flow of oil, how long would it take to pump the tank dry? 5seconds maybe? 10?
We run 3/8 pitch, 063 gauge, 36" bars all the time with Stihl MS 660. When I drink a Bud Light in the evening and accidentally count to 105 instead of 114, I drop down to a 32" bar for a slight change of pace the next day.
Roll Tide
Trolltide
I bet the guy who started this thread is thinking WTF I just wanted to know about bar length on a 661 haha. Derail complete !
Chris-PA
Where the Wild Things Are
Right - and I can't imagine that a 0.050" bar groove would not be able to flow that much oil easily. Maybe if it gets packed with chips it's a limitation?
Once again I don't know if the extra volume is the reason but I do know that on a 3/8 Stihl chain the space between the drive links is slightly bigger than a drive link. And in that space an .063 groove will have 25% or so more volume then an .050 groove. Per published specs, the 661 holds 360cc of oil. Assuming fuel and oil are synchronized and assuming further that it burns a tank in 20 minutes then the oiler would be putting out 18cc a minute. If burn rate was 10 minutes then oil would be 36cc per minute. Basic arithmetic I know, oiling differences between bar gauges and a whole lot more things I don't.
To the OP, I say that if a 660 will pull a 36" then so will a 661. I haven't run either so I won't comment further.
Ron
To the OP, I say that if a 660 will pull a 36" then so will a 661. I haven't run either so I won't comment further.
Ron
Mike has a good point about the oil hole if the oil hole feeds through the bottom of the rail (i.e. between the rails) and is the same gauge as the groove - a .063 hole is almost 59% bigger than a .050 hole. So theoretically it can flow into the bar 59% more oil. If this is it then why not drill a second hole in the .050 bars that receive oil off the bottom?
Ron
Ron
tacomatrd98
ArboristSite Guru
A .063 rail may be able to carry more oil, but if the stingy oil pumps on modern stihls cant fill the extra space, what's the point. IMHO, stihls do not oil as well as they should. They are a first class product but the oilers are better at pleasing the EPA vs actually lubing the rails. On long bars, (actually all the time) I have gotten in the habit of revving the saw/ blipping the throttle in between cuts just to keep the chain spinning and oil flowing to keep things lubed up well. Knock on wood, I've never locked up a nose sprocket or really burnt a rail and i run 3/8 .050 on everything. I've used a 36" quite a bit on my 660 with the standard pump. While not wet, it keeps up ok.
hseII
Addicted to ArboristSite
hseII
Addicted to ArboristSite
Party Fowl Mista.
All's mine is 0.063" except for Picco: .325", 3/8", and 404".
Cause I like it messy
hseII
Addicted to ArboristSite
There's more oil on the ground when I piss rev with 0.063" that there is with 0.050".
I know things are different and bigger in Texas, but you're suppose to sharpen the cutters not the drive links
. Ron
Oil on the ground doesn't keep the bar any cooler.
Redbull needs to run a test on bar temps vs. oiler setting.
BTW I run a 32" .404 on my MS660. Seems to work just fine.
Redbull needs to run a test on bar temps vs. oiler setting.
BTW I run a 32" .404 on my MS660. Seems to work just fine.
Trx250r180
Saw polisher
Up to a 25 inch bar. 050 is fine, 28 up I prefer. 063, inside my clutch cover is always oily so it must oil better, again I cut softwoods so my results may be different than other regions, my. 050 used to burn the paint off the bars fast, I do not have that problem with .063 so bar wear is also less with .063
Trx250r180
Saw polisher
Uh
Wider drivers will hold more volume between the drive links. Front to back is the same but the side to side is wider to get more volume,this keeps the bar and chain cooler, chain will stretch less also
Wider drivers will hold more volume between the drive links. Front to back is the same but the side to side is wider to get more volume,this keeps the bar and chain cooler, chain will stretch less also
