Dolmar 7900 Big Bore Kit Review

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Howdy,
At this time we can only take back orders for future shipment. If you look at the thread from the beginning , you'll see Brad had to narrow the skirts on the pistons. So far, I think this is the only issue with bringing them to market. It will take 6-8 weeks to have them on the shelf once we give the OK. Once again this is considering that the piston is the only change. I also have a 2mm thick gasket in the works, so this kit will also fit the Solo 665, 675, and 681.
Gregg


Hey Gregg, there isn’t any chance I could talk you into a big bore kit for the 5100 Dolmar is there?
If you do, count me in on that one also!
 
Do you guys ever go through the trouble of dynoing your BBK's? Just curious what these saws would be comperable to powerwise.
 
I ran it with the same bar and chain as a Solo 681 at the GTG. The BB outcut it by a small margin. However, the 681 had a 7-pin and the BB had a 8-pin. We also did some timed cuts with work chains in some firewood and the BB was beating a 7900 as well. I've got the saw for sale in the Tradin Post.
 
Any more news or testing results with this kit. I really want to get one for my 6401.

+1

Was sort of hoping the hear some of the thougths/comments from a few of the guys at the GTG if they had a chance to run it? But might be sounding like a broken record. :deadhorse:

The time shown in the small 10" x10" beam dosen't- really seem to show how this saw should run.

Any chance of this saw or one like it, being at the GTG in the PNW?


NIB DCS6401 waiting on the PC 7900 or BB? & air filter VS
 
I ran it with the same bar and chain as a Solo 681 at the GTG. The BB outcut it by a small margin. However, the 681 had a 7-pin and the BB had a 8-pin.

How do you think the the BB would have done against the 681 if it would have had a 7 pin also? Thanks
 
The time shown in the small 10" x10" beam dosen't- really seem to show how this saw should run.
That's because the other saws were wearing fast chains and mine had a regular round ground Stihl RSC on it. We did not record the times when I ran a faster chain on it. That was all done after the racing was done.

How do you think the the BB would have done against the 681 if it would have had a 7 pin also? Thanks
I have no idea. The only way to know would be to try it.

Did you have base gasket in the BB?
It was built just as desribed in the review thread. No base gasket.
 
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I think Brad described it perfect. If both the 681 and 6400BB wore the same B/C and 7/8pin they would be neck in neck. That Dolmar BBK would be a good deal.
 
I ran both the BB and my stock 7900. I liked the BB and will get one. I could feel a difference in the amount of torque the BB made. I have always felt the 7900 is a great saw but you can't lean on them with a big bar the BB made a difference and I felt I could lean on it more.

The 681 solo was impressive. Very strong.
 
Options are always nice. Being around 120 for a BB kit makes it close to the 190 that buys a OEM 7900 top end. I think either way you go, the Dolmar is a nice saw for the money. I will have one some day.:cheers:

Brad, how did it compare to the 064?
 
Brad, how did it compare to the 064?

7900BB 6.97
064 7.00

Both were wearing round ground Stihl RSC. The 064 is still bone stock except for the muffler mod. The 7900BB is muff modded as well. Interesting results. I believe they're both 85cc. I'm very impressed with the 064 for a stock saw. I should have the 066 P&C in a few days. It's on its way.
 
I ordered mine a few days ago, Looks like I'll be getting one of these in the first batch. Can't wait to put mine on my 6401. I just use it for (mainly)hurricane cleanup around mine and my neighbors houses but the added torque will be nice when I tangle with one of these big oaks when they go down in a storm.
 
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