My Dolmar 7900 and Solo 681.

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Okay. After the suspenseful, dramatic, intense anticipation, I am here to reveal what you already know - I got me a Sling'r Ported 7900!!! :D

But the anticipation wasn't what I had received in the mail - it's running it with the Snellerized Solo 681 I acquired very recently. First, let me say that both saws are just plain SICK. They're both a little bit different and shine in their own way as they are meant to serve slightly different purposes.

When purchased brand new in August of '09, my 7900 (stock) was very impressive. It's antivibes and air filtration with the HD air kit are outstanding. Though over time, I was looking to get more out of it since I mainly use it as a milling saw. Every now and again I dive into some nice hardwood for lumber and that's where I could really use the extra torque. I got a hold of Jasha and sent my 79'er off to Cali. I explained to him that I wanted my 7900 not necessarily to be fast, but to have a lot of torque - I want'er to run rich and be nice and FAT! Actual cutting speed in this case is put on the back burner since I really want to be able to lean into the saw after it's ported.

While waiting for my 7900 to come back, I unexpectedly made a little deal with Brad Snelling to buy his Solo 681. He had already ported it and gave it an unlimited coil. At a recent GTG in Ohio, he was NOT impressed with the 681's performance. He went back to the drawing board to see what he could do with it to make it worthy. It being Brad doing the port work - it was a success! The 681 was running just behind his 372 and his 440 with a 460 top end - his exact quote to me in a PM was "this 681 is now running right with the fastest of my 70cc saws". I got the 681 and put'er into some wood - and good god this saw is FAST! It also has an impressive amount of torque as well. For me, it's purpose is to be a damn good work saw while the 7900 wears the Alaskan SawMill.

Now that you know a little bit of history - time for the good part!! :)


Here's a video of the the 681. It's a cold start and me revving the engine so you can hear it's note. It's pretty throaty in comparison to the 7900, and it's also running quite a bit leaner - which is what I want. Brad put quite a bit of time into this saw, and it paid off pretty darn well. It has one extra port in the muffler and the stock port has not been played with. This saw kind of makes you think of a newer turbo charged import - something like a Toyota Supra. It's sleek and has a real smooth yet fast power band - notice the smooth and fast idle. I love it. This saw is a real keeper, and I couldn't be happier with what Brad did to it.

Solo 681: Cold start.

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http://www.youtube.com/watch?v=Tcu5pTb-9-E
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Now for the 7900. This saw is down right insane. Jasha certainly knows what he's doing - you make the request and he definitely delivers. I wanted torque, he gave me torque. I wanted rich, he gave me rich. This saw has a ton of ass behind it - and that's exactly what the doctor ordered. I'm really happy with the Sling'r port job. The muffler is modded a lot like the muffler on the 681. It has a second port and the stock port has been left alone. This thing sounds downright nasty. It isn't as "zingy" as the 681, but it roars. It's idle is definitely different from the 681 - it's real poppy, almost as if it's an old muscle car with a big cam. It doesn't sound as throaty as the 681 but when it's idling and being revved at WOT you can tell it has some serious balls. Dang Jasha, what did you do to this thing?! :)

Dolmar 7900: Cold start.

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http://www.youtube.com/watch?v=Gz-366zcc3I
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Now for actually running the saws. Both saws are running 7 pin rims with a 24" Oregon bar with 3/8, 050 full chisel Oregon LGX chain. They're both running 93 octane gas with Klotz R50 mix at 40:1. Both saws are using Stihl BioPlus biodegradable bar and chain oil. The saws share the same bar - my 24" Windsor SpeedTip hasn't shown up from Bailey's yet. Dan (the westapartan) is running the saws in each video. I already took much time prior to recording to run and compare each saw while in and out of the cut. I'm not running the saws in the videos because I wanted to make sure I got good footage of the saws in question.


__________________________________


Obviously, the 681 is the winner when it comes to speed. The chain is practically singing around that bar. It screams through bar sized (24") wood without a care in the world. It's a darned fun saw to run. It's awesome knowing I have such a sweet worksaw. Thanks to Brad Snelling of course. :cheers:

Solo 681: In wood.

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http://www.youtube.com/watch?v=nyM1LTShfB0
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The 7900 is slower, but it's what I expected (and also hoped for) because I wanted torque, not speed. The saw is running pretty rich, and I think it could be leaned out quite a bit and it would keep up with the 681 rather nicely. But I am comparing the saws in the condition that I will be using them - I'm currently not leaning them out to see which is faster...... yet. :D The 7900 is a friggin' hoss, a real brute you can lean right into. You can push the snot out of this thing and it doesn't slow down. It'll cut through the knottiest pieces of the hardest of hardwoods like it's not even cutting. I milled with it for a little while with Dan yesterday and I'm very impressed with Jasha's results.

Dolmar 7900: In wood.

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http://www.youtube.com/watch?v=DwcAyA5eYhI
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The verdict? Well, I don't really know if there is one. I am absolutely ecstatic about each saw and the results. I'm not disappointed at all. What you are looking at are two very alike saws built by two different builders with intentions of building the saw for a slightly different purpose. The unfortunate thing is you can see how much faster the 681 is than the 7900, but you won't be able to feel how much more you can push on the 7900 by viewing the video. As the viewer, you'll only be able to comprehend one of the saws advantages and not the others. Which is okay - most people seem to be intrigued by cutting speed anyways - so you get to view the latter (as defined by me observing that most like speed more than anything else).

I have two great saws thanks to Brad and Jasha. Gentlemen, my hat goes off to you. Take a bow, and know that you are both great at what you do. I'm not kissing ass, I'm just recognizing talent and experienced workmanship. Thanks again to the both of you for doing such an outstanding job. It's guys like you who keep us all humble here on AS - even if some don't want to admit it. :laugh: :)


Soon enough I plan on cleaning the saws up really good and doing a comparison of aesthetics and construction. But I think I have enough to keep us busy for now.


:greenchainsaw:
 
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That was an excellent write up, Jason! Thanks for sharing. How many tanks of fuel have you put through the Solo since you got it? It sounds like it might be breaking in and freeing up. I had only put a couple tanks of fuel through it. The keyless flywheel is obviously holding well.
 
That was an excellent write up, Jason! Thanks for sharing. How many tanks of fuel have you put through the Solo since you got it? It sounds like it might be breaking in and freeing up. I had only put a couple tanks of fuel through it. The keyless flywheel is obviously holding well.

Thanks a lot Brad! :)

I've run about 3.5 tanks through it so far. It doesn't take long to fly through fuel with that saw! I'm sure the 7900 will consume fuel just as fast. I've probably run about 3/4 of a tank through my 79'er - all the fuel consumption has been strictly from playing around! :clap:

:greenchainsaw:
 
One bit of advise. I'd recommend that you give the saws a little more warm up time before going WOT. The piston expands faster than the cylinder. So you want to let the cylinder warm up before going after it, or you increase the risk of a cold seizure. It can and has happened, though not often.
 
^^^^^^

Tee-he-he....

Yeah I get that a lot as comments from viewers on YouTube - Andyshine recently suggested that to me as well.

It's rather dumb to do so - but I only do it in the videos - there's something about seeing that blue smoke on a cold start at WOT. :) Still rather dumb? Yes.

But I figure if I do it once and record it, I get to view it over and over but will only have done it once. :laugh:

Horrible logic on my part, I know. I'm just a big weirdo and a goofball kinda guy I guess. :D
 
Great write up and nice vids

You two are collecting some sick saws for sure.



Mr. HE:cool:
 
very good comparison/video work. Good quality stuff to look indulge in while at work too:popcorn:
 
One bit of advise. I'd recommend that you give the saws a little more warm up time before going WOT. The piston expands faster than the cylinder. So you want to let the cylinder warm up before going after it, or you increase the risk of a cold seizure. It can and has happened, though not often.

Hi Brad

How much time do you recomend? I usually start the saw and let it idle as long as it takes to put on eye&ear protection. Approx. 30sec. Do you believe that that is enough?

7
 
Hi Brad

How much time do you recomend? I usually start the saw and let it idle as long as it takes to put on eye&ear protection. Approx. 30sec. Do you believe that that is enough?

7

Probably not, IMHO. Most saws you can touch the cylinder fins above the clutch. Make sure they're warm before putting much load on it. If I've got little stuff to cut, I'll do that to let the saw get up to temperature before getting into the bigger stuff.
 
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