Modifying choke flap on MS260?

[rustyb]

Hi,

I was excited to see BWalkers post re this simple mod so gave it a shot last night. I was hoping to feel some seat-of-the-pants performance gains but in all honesty, I could not tell any difference. However, a few weeks had passed since I last used this saw so maybe that had something to do with it. I now wished I had done some cutting just prior to making the mod.

Anyhow, I was wondering if anyone who has done this little mod has actually done any timed cuts or other tests to verify performance gains.

BTW. I did readjust my carb which is the fully adj version.

Thanks,
r

 

[bwalker]

Rusty, Keep in mind my saw has been ported and as such has a increased appetite for air. Mine acftually runs even better with the filter off, but that not really a option for a working saw. BTW what rpm did you set it to? Did you try the cut and feel method to obtain the the correct hs screw setting?

 

[rustyb]

Ben,

I'm not sure of the RPM as I don't have a tach. I just set by ear.....doing the standard adjustments and finalizing them by turning in the HS until screaming then back to a slight 4-cycle. I repeated this and did some cuts & adjustments. It runs quite well..... but how much gain from the choke mod I'm getting I don't know. It would make sense that your 260 would gain more being that it's ported. Mine's stock except for the muffler & adj carb.

I also just had a thought that my muffler could probably stand to be opened a tad more as the opening is smaller than the exhaust port. Perhaps doing this would get me a noticable gain being that the saws aircleaner will now allow more air in. What do you think of that theroy?

The lesson I have gained here is to always do some cutting to get a good feel for the saw right before making a mod.

Thanks.