MS461 Tuning Question

[markds2]

I have been trying to tune my stock MS461, with a mild muffler mod and don't quite know where to go next..... After warming it up I checked with my Stihl EDT5 tach and it seemed to be 4 stroking at 13,800 or thereabouts, I had a fiddle with the H screw but it didn't seem to make much of a difference until I had it nearly 2 turns out where the rpm dropped to 13,500..... this is all before I realised it has a limited coil! Why is it then maxing out at 13,800? I checked tonight and sure enough, it has the stock 1128 1313 limited coil which shouldn't let the saw go above 13,500. Compression sits at a nice 175psi and all I have done is to double the size of the stock muffler outlet. Question is, was there a version of the coil with a higher rpm limit, or do limited coils do funny things to tachs? Currently, the H screw is 1.5 turns out (limit cap pulled) and its sitting at just under 13,800rpm WOT. Also, should I swap the stock coil out for an unlimited coil to simplify tuning? Any help would be appreciated.

 

[Deets066]

461 coil is limited at 13,800 best I remember. I swapped mine with an 046 coil.

 

[Glock37]

Yes as you get too the limit tachs will go crazy giving readings all over the place

Replace coil with a 460 coil and tach will act normally


Sent from my iPhone using Tapatalk

 

[huskyboy]

Richen it until it just starts to come off the limiter and leave it there if you don’t want to replace the coil. The one I tuned liked it there.

 

[markds2]

Thanks for your help chaps, as the saw isn't ported I don't see there's a lot of point replacing the coil so I'll go along with what @huskyboy suggests.