Question for the pros. I've always tuned by ear and my saws have ran well. I have placed a tach on a couple and see that they are running around 1500rpm less than the stihl manual suggests as max rpm not under load. While trying to increase the rpm using the tach it feels as I may be pushing a little to hard. And both that I've done this with sorta pulsed it the top end. Is this just par for the coarse? Or should I back them off as they where.
Thanks. Jason.
Jason.
A few things to take into account along with the quality of the Tac you use to take any readings (0.5 second re fresh rate is good).
Is the saw coil RPM limited ....
The heat of the saw when you make the adjustment...
The fuel to oil ratio that the saw will run on.. IF.. its different to the mix your using to tune the saw on...(this is important if your working on saws that are not yours)
Air filter state....
Is the saw in a good overall state and well maintained.....
Is the saw going to be used for milling....
I always ......Tune with the bar and chain on plus cut for a test, then check
These are some things to take on board and can help form the result in how close the saws RPM can/should be set to the makers guide.
Myself...I do use a Tac (PET 302) for the final tune ...even with a saw that is RPM limited as it can still be to lean or to rich.
On a customers stock saw I stay just under the makers MAX by 200-300 rpm to allow for a bit of latitude .
The... "free load RPM " with a well warmed up saw is the best way to get the right state of tune through the rev range as per the manufacturers specs.