I was just looking at the Oregon webpage matching up a bar and chain for an 075, it says that the 075 uses an 8 tooth sprocket, I would think that this saw would be optimized with a 7 not an 8 tooth on it, unless an 8 is standard for this saw and a 9 is optional or was at one point in time. Kevin, perhaps you know which sprocket is right for this saw. I am only talking about a STOCK 075AV running regular fuel for sawmilling not racing, just to make sure that there are no misunderstandings there. I dont have a clue which one is the right one, I think a 7 tooth would be best, but an 8 is the one listed for an 075 by Oregon cutting systems. TIA.
calm down icalm down i've not sent it yet
missed the 075 on ebay uk by £10
got stuck in traffic taking linda to work
but have found parts in germany so we'll see what happens now
do you think i could put the 84 on the pulling side with the other 75 pushing (so to speak) to finish a job or would that be to unbalanced?
I'll go out on a limb without my rope and say 8 tooth for 3/8 and 7 with .404.
Would a 7 3/8 bo too much torque? Just wondering.
Likely be more chain speed and less torque.
You''ll be driving a smaller chain faster with the 7.
If you are cutting big wood you would likely be better off with the 8 and 3/8 pitch.
Kevin, I have no idea what I'd do without your expertise on this sort of thing. I'm confused though, you say the 7 tooth will give more speed with a smaller chain, while an 8 will work better in bigger logs. Are you sure that you didnt make a mistake there? It just didnt sound quite right to me as I have been taught that a 7 tooth will give lower chain speeds, but more torque while an 8 will give more chain speed with slightly less torque. This is what I learned if I'm wrong then please correct me. Thanks for the help guys, I appreciate your assistance.
If I'm wrong it won't be long before someone corrects me. :D
Try to think of it like a 10 speed bike.
Small sprocket at the back for more speed on the flats and a large sprocket at the back for the hills while the horsepower(you) remains the same.
Ok it all seems to be coming together now, thanks for clearing that up for me. I have a slight issue understanding how that can be that I get more torque with an 8 tooth and more chain speed with the 7, but since you explained it to me, I understand it better. Thanks kevin, you are an asset to us all.
QuoteIf I'm wrong it won't be long before someone corrects me. :D
Try to think of it like a 10 speed bike.
Small sprocket at the back for more speed on the flats and a large sprocket at the back for the hills while the horsepower(you) remains the same.
Your wish is my command. Your analogy would be correct if you were driving the chain from the rear axle on the bike for some reason.
For each drive sprocket revolution, a 3/8×7 will pull 5.25 inches of chain, a .404×7 will pull 5.66 inches, and a 3/8×8 will pull 6.0 inches.
Yabut the drive sprocket on the chainsaw is at the rear.
The drive sprocket on the chainsaw is the equivalent of the front sprocket on your bike.
I'm not going to argue with you; you wanted to be corrected and I had to register just to do so. Do the math and you'll come up with the figures I provided.
This board software sucks harder than any I've ever seen. Got to enable javascript just to use the stupid stuff and the quoted portions are black text on a black background.
Kevin, me thinks he's got ya on the sproket thing. I think you're looking at it backwards.
BUT, I have NO idee what he's talking about on the rest. I never had no problem with any software ??? ??? ???
There's no argument from me, it's been awhile since I did any sprocket changing and I'm too tired to look into it tonight .
If you're right that's good with me.
Thanks for your input.
Turn the bike upside down. Put it on the big gear. Spin the rear wheel. With the big gear the pedal will be going really really fast. Put the rear end on a small gear. Turn the wheel. The pedal won't be moving as fast. There will be more torque at the pedal with the small gear, and more speed with the big gear.
I made a mistake one time too, just hard to remember when ;D 8) 8) 8)
oldsaw, in the manner that you compile data and parrot it I'm surprised you had to ask this question; well, not really, but that's another topic for another time maybe.
The Oregon site suggests 3/8×8 if you want to use the lighter chain with more cutters per given loop. That saw should be able to pull that all day every day. If for some odd reason you wanted to both use the lighter chain and an effectively higher "gear ratio" (lower gear in typical terminology) you could get Oregon's Standard 7 Spline 3/8×7 rim. Would not be a smart move in my opinion.
If you must go with 3/8 chain stick with the 8-pin driver.
If you want slightly less chain speed as well as pulling fewer, heavier cutters per loop revolution and with more authority then stick with the .404×7 setup, as Oregon also recommends. That saw might could pull the .404×8 quite satisfactorily.
Glen
I had it backwards, here's a bit from Madsens ...
Information on Rim Sprocket Size & Gearing
http://www.madsens1.com/sprktsaw.htm
glens, you are getting a poor start here. This is not a public commercial site this is MY website.You had to register for that reason. I would appreciate it if you keep you negative thoughts to your self and the language appropriate for a family site, which this is. Is is listed as a resource by several educational organizations . Save tha attitude for where ever it is you came from and we will get along fine. Your comments put you in a very poor light in front of THOUSANDS of guests and also our members that appreciate what we have here.
That's what I like about this site, you can always get the right answer by putting out the wrong one first. :D
Jeff,
There's no good reason to /require/ javascript be enabled to do anything being done here, and you have to admit that black text on a black background is pretty questionable in terms of usability design (and I should be able to insert simple HTML directives to do things like make the word "require" above be presented in an italic font face). I appreciate you wanting a friendly atmosphere. Perhaps you did not realize you were being unfriendly via the site setup. This is one of the problems which arise when testing/evaluating software configurations without considering some of the simpler, fully standard ways it might be used by others.
Kevin,
That Madsens link is generally good but contains a couple of errors. They say
"The eight tooth sprocket has the same effect as a high gear ratio rear end has in a truck - the speed is great, but you better have plenty of horsepower when you come to a hill."
which is exactly backwards. A high gear *ratio* means the input (in this case) is a higher multiple of the output while a low gear *ratio* is what they're describing. It's a common mistake, much like saying current flows from positive to negative in a DC circuit when in reality the current flow is a result of the electrons migrating toward the positive.
The second mistake is much the same, where they say
"the 3/8 X 7 sprocket is the smallest diameter of all sprockets. This gives these small pro saws low "gearing" and enables them to run fairly long bars"
when it should maybe say ``gives these small pro saws a lower "gear"...'' (or more correctly ``higher "gearing"...''). The result of what they're trying to say is the crank throw has a greater leverage against the pitch diameter of the drive sprocket as the sprockets decreases in pitch diameter (the pitch diameter is the circle through which the link rivets travel).
The mistakes should not be perpetuated merely because "sixty million Frenchmen can't be wrong".
I've read through many of the threads in this forum over the last week or so and finally felt like I had to address something. My apologies for the manner in which I've done it.
Glen
Glen, as to the problems you are having with the forum. THey are your problems due to configuration of your computer. Either you have an old, devective, or incompatable browser. You are the ONLY one seeing the forum in that manner. You should not be so quick to point when the problem is your own. In most cases I make every effort to help a member with a computer glitch. I promise you, this is your defect.
Remember also as I said. This is my website. I might want it pink some day, and if so, pink it'll be with maybe green polka dots. Maybe I'll make every instance on the forum where it says "C.h.a.i.n.s.a.w" say: "tree whacker"
I took the time to do a screen shot. Here is a picture of your post. This is what everyone else sees and what you would see if your computer was working properly.
https://forestryforum.com/images/03_21_04/post.gif
QuoteRemember also as I said. This is my website. I might want it pink some day, and if so, pink it'll be with maybe green polka dots. Maybe I'll make every instance on the forum where it says "C.h.a.i.n.s.a.w" say: "tree whacker"
(https://forestryforum.com/smile/headscratch.gif)
That is well cool Jeff, I kinda like it. strange but cool. Lets keep it this way for a while :D the bright green is really cool to look at, its easier on my eyes to read posts now. Nicely done Jeff, nicely done.
Huh? :D
(https://forestryforum.com/smile/headscratch.gif)
(https://forestryforum.com/smile/headscratch.gif)
(https://forestryforum.com/smile/headscratch.gif)
What the...... I was just lookin at this board a minute ago and everything was a different color, now its all normal, I'm seein things aint I? Its either that or I'm really havin a freaky hallucination here. I better go lay down for a while, this is confusing. Oh well, IF I was seeing the colors I thought I was, They were pretty cool to me, If not, then I'd better see my doctor soon :D
Huh? Colors?
Hi Jeff,
Glen is rather vehement in his dislike for all things Microsoft and has had multiple compatibility problems on other forums as well, all of which are the fault of the website webmasters. I cannot tell you what browser he is using because I have never heard of it before. On the other hand he is quite intelligent and has added interesting perspectives on several topics.
And he was correct on the sprocket gearing thing, although his last post was incomprehensible to me. ;)
I might have to abandon the shop-vac driven D9 turbo chainsaw in favor of dat bicycle driven chainsaw idea of Kevin's. I sure hope we don't have a quiz on shifting it though ;D
I'm not putting up with him. He is rude and has no place here. He can stay at those other forums. I dont care how intelligent he is as he has proven otherwise to me. I got better things to do then molycottle someone with an attitude. I am throwinghim out of my house. What he is doing is no different then if he walked in the front door of my home for the first time and said that the color of my house sucked, that my dog was ugly and that my tastes were bad and oh by the way, this chair is unconfortable. He would be escorted out on his ass.
BILL GATES IS MY HERO
And basic social skills count for something... even on the net ;)
Making your 1st post a 'this place sucks' ... oh dear... ::)
QuoteI'm not putting up with him. He is rude and has no place here. He can stay at those other forums. I dont care how intelligent he is as he has proven otherwise to me. I got better things to do then molycottle someone with an attitude. I am throwinghim out of my house. What he is doing is no different then if he walked in the front door of my home for the first time and said that the color of my house sucked, that my dog was ugly and that my tastes were bad and oh by the way, this chair is unconfortable. He would be escorted out on his ass.
BILL GATES IS MY HERO
Jeff, You're the BOSS! Thanks for keeeping the ship so nice and tight.That reminds me, if I stop by your place I'll keep my coments to myself, OK? You work hard to keep things nice and friendly here, I appreciate it a lot.
(https://forestryforum.com/images/03_21_04/trollworldus_1785_6226%5B1%5D.gif)
Forsest Troll; Known for poor upbringing , rudeness, lowself esteem .
Known predators in the wild ....administrators and loyal members.
Bravo Jeff! - The one thing unique about this site is the respect, kindness, and patience the members show for each other; even when we ask a dumb question or one that's been asked many times before. If someone says something wrong or incorrect an other member will help without making anyone feel like an ass (usually).
I get sick and tired of the arrogance and rudeness that exists on other forums that people occasionally try to bring here. We have folks here from many walks and different education backgrounds. People with different talents, skills, opinions, and sizes (bigger is better) and that's what makes this place work. We don't have to worry about someone jumping all over us because rudeness isn't tolerated.
Mark
Jeff works hard to keep this site so friendly, I'm glad he does. Its nice to be able to ask a question and get nice honest answers that are probably correct, plus nobody get picked on for asking dumb, or odd questions. I dont know what we'd do without him making things work so well, personally I'd go nuts. I believe we've earned the right to say we're one of the most friendly places on the web. Nothing better than a wealth of knowledge and its owners willing to share it and educate the rest of us, unless you add a BIG stack of hundred dollar bills for each one of us, but I doubt the stack of $100s thing is gonna happen not unless I hit the lottery!.
jeff what dog you got then? ;)
old saw where you find the blue (on my screen) ;) head scratcher?
iain, there is a whole bunch more smilies when you click on the more smilies link.
We have a
Australian Shepherd named Sydney
An Alaskan Husky named Juno
and a yorky/pomeranian mix named scooter.
Pick one. :) I'll slap on some stamps and...
Well Jeff, I'd like to see what they look like. I'm sure they're much nicer than my uncle. :D
Thanks for allowin' me to stay, Jeff, I'll be good. :-*
Back to the original question. When I was racin' motorcycles if we wanted more speed we'd put a bigger sprocket on the engine, or a smaller one on the wheel. For better accelleration just the opposite. On your chainsaw the sprocket on the engine end gives the same effect as on the motorcycle engine. Bigger sprocket=faster chain speed, smaller sprocket=more torque. :P I hope that helps oldsaw.
Thats how I had figured it worked, Kevins post earlier just had the facts backwards and got me all confused, I'm glad I wasnt on the wrong track in the first place. Stan, Thanks you have helped out a great deal for me here.
the boys want the husky :)
found the smileys
i see the words MORE SMILEYS every time i type
but ive only just READ them just now linda says its just typical male observation >:(
Dang it I wanted the husky, then second choice is the austrialian shepard. My aunt had one when I was younger, lovable and smart was he.
jeff was juno the name of a lead dog on a famous team?
im trying hard to remember
Its the capital city in Alaska. We just spell it like its pronounced. I posted some pics of the dogs on the general board in a thread called madogs
In these parts, Jeff, tellin' a man his dawg's ugly, is taken as a compliment. :D :D
I had a similar problem. I have a Stihl 026 Pro. The only chain listed for it is .325, 63 gauge. I have a lot of 3/8", 50 gauge chain that I want to use. I wanted to know if the 7 tooth sprocket that's used with the .325 chain was the correct one for the 3/8" chain. I went to a Stihl dealer last week, and we looked through his book. Both chains use the 7 tooth sprocket. The .325 chain has 74 drive links for an 18" chain, and the 3/8" chain has 66 drive links for the 18" chain. I think that the 8 tooth sprocket is for a smaller chain.