When and how did you hurt your ankle Andy? I'm sorry to hear that. I'm also glad to hear that your saw was running rich. That can make a huge difference, especially if you were a whole turn out. I'm anxious to hear how it turns out.
So who has modded there Dolmar 7900??
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Andyshine, sorry to hear about the ankle. Ouch! 
Do you have a tach? Only real way to set carb on the 7900 IMHO.
Depending on the cold weather, mine could change big time. I think I was close to 2-2.5 turns min out on my ole one in 30 degree weather to get if off the limiter.
Do you have a tach? Only real way to set carb on the 7900 IMHO.
Depending on the cold weather, mine could change big time. I think I was close to 2-2.5 turns min out on my ole one in 30 degree weather to get if off the limiter.
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I was carrying some boxes down the steps at my parents on Christmas eve, I missed the last step and I badly rolled my ankle, it literally went pop. The doc said I need to stay off of it for 2 to 3 weeks, then com back in for a check up.
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I have an EDT-5. Ed said to set it just at the limiter for work, and about an 1/8 of a turn in past that for cutting cookies. When I can I'll just make some timed cuts to see ware it likes to be.
Brad. Kevin. I've been in some pain, the Percocet helps the pain, but it also makes me sick to my stomach.
Brad. Kevin. I've been in some pain, the Percocet helps the pain, but it also makes me sick to my stomach.
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davefr
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The 7900 has a rev limiter so a tach isn't that useful. I'm not sure how to set a 7900 other then to cut wood. Anyone have a service manual. What does it say?
The best way to tune any saw is to do it with timed cuts in the wood. However, I do that while checking WOT RPMs at concurrently. That way I can retuned it to that setting any time.
Well the EDT-5 tach sure worked for me to tune the 7900. Right against the rev-limiter just as Andyshine was told too.
Even got a few ribbons with it cookie cutting and it sure would rip cut a log.
Knowing how to use a tach on a rev-limited saw, may just be the key eh.
davefr
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Well the EDT-5 tach sure worked for me to tune the 7900. Right against the rev-limiter just as Andyshine was told too.
Even got a few ribbons with it cookie cutting and it sure would rip cut a log.
Knowing how to use a tach on a rev-limited saw, may just be the key eh.
Exactly how do you tune it in the shop with a tach? Do you go way rich and gradually lean it out until you hit 13.5k?
My 7900 ran perfect before my muffler mod using the factory setting which was all the to the limit of H. After the muffler mod it's even better but I'm worried that it should be richened slightly. I was planning on cutting off the limiter tab and going 1/8 turn richer to compensate for the mod.
Without a pile of wood to cut, how do you optimize the 7900 tune in the shop with a tach???
TIA. These rev. limiting saws seem like they can fool you.
P.S. Anyone have a factory service manual for both the 5100 and 7900 in pdf? I'd be grateful for a copy.
You need to get rid of the restrictor tabs (limiters) on the carb.
Put a good tach on it with a fast refresh. Set rich at first and then take it just before the 13,500 rev-limiter (out of the wood). mine liked 13,440. But the colder it got the richer I would have to go to keep it off the limiter. or you could just set rich at 13K and cut wood and forget about it.
This is just what worked for me running 7900 and never had a problem tuning a rev-limited saw with a TACH. IMHO you have to have a tach for the rev-limited saw to tune them right. But what do I know.
Put a good tach on it with a fast refresh. Set rich at first and then take it just before the 13,500 rev-limiter (out of the wood). mine liked 13,440. But the colder it got the richer I would have to go to keep it off the limiter. or you could just set rich at 13K and cut wood and forget about it.
This is just what worked for me running 7900 and never had a problem tuning a rev-limited saw with a TACH. IMHO you have to have a tach for the rev-limited saw to tune them right. But what do I know.
Cut ...Can you post a video of your 7900 cutting with the 32" bar.....Mine cut great with a 28" and I have not had time to try a 32" yet..
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The 7900 is now in Oregon earning a living, so I could get this new 084 I wanted sooooooo BAD.
Mine, key word MINE cut great with a 32" bar.
You want a pic of the 32" bar? Because I dont do videos for here anymore.
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The 7900 is now in Oregon earning a living, so I could get this new 084 I wanted sooooooo BAD.
Mine, key word MINE cut great with a 32" bar.
You want a pic of the 32" bar? Because I dont do videos for here anymore.
Lets see the big 32"
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Just how many times does a guy have to look at the same LITTLE 32" bar in the same pics to get the idea that I ran a 32" on the 7900.
Whats the big deal anyways?
Some pics from when it was new. :monkey:
Just wanted to see a picture of the 32" actually cutting .........Here is a 28"
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Austin1
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Ya let's see it! a 32'' tree were I live is huge!
P.S I like my 7900 and how Quiet it is I have read hear not many gains trying to port it but who know's what's in it's the future for my new baby. But Stock I like it it is really more saw than I need even cutting at 5000ft . But Dam it's a nice saw.
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Austin1
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For those of us who are curious that's allJust how many times does a guy have to look at the same LITTLE 32" bar in the same pics to get the idea that I ran a 32" on the 7900.
Whats the big deal anyways?
Some pics from when it was new. :monkey:
romeo
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Redprospector has a full race port 7900. It is wicked fast, much faster than his stocker. I think the problem with them is limited coil when modding, they are pretty peaky to start with and the rev limiter is set to low for the saw IMO.
romeo
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There are two ways around it. The first is to find a non limited 7900 coil. The other, is to adapt a different ignition system to it. I have heard that they will easily turn a four stroking 15k stock if you can get around the limiter.
Romeo
Yeah, I new all about the RS coil abroad and the Husky coil change over. But it was my work go to saw and gtg fun saw 0-80cc.
So if it wasn't a direct bolt up I wasn't messing with changing the flywheel and timing etc to run a Husky coil.
Yeah, I new all about the RS coil abroad and the Husky coil change over. But it was my work go to saw and gtg fun saw 0-80cc.
So if it wasn't a direct bolt up I wasn't messing with changing the flywheel and timing etc to run a Husky coil.
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