How big a hole?

[woodyguy]

I shall tune it on a tacho so interesting to see if there is much change needed.

[Gerbutt]

Yeah it'll be interesting to see the results!

[peatff]

If you make a too big hole you could weld a repair washer on to cut it back down. Do you drill the hole straight through the lot or just in the outer casing of the silencer ?

[wisecobandit]

As Spud and WYK say its around 80% size of the exhaust port size is prob the best guide line.

Ive always been tempted to try and make an exhaust outlet you can fit a separate flat plate/screen in that you could either adjust or replace easily so to allow you to fiddle and find the sweet spot-but that's me just thinking out loud.

[mikerecike]

As Spud and WYK say its around 80% size of the exhaust port size is prob the best guide line.

Ive always been tempted to try and make an exhaust outlet you can fit a separate flat plate/screen in that you could either adjust or replace easily so to allow you to fiddle and find the sweet spot-but that's me just thinking out loud.

 

like it:thumbup1: got a pic of one?

[wisecobandit]

like it:thumbup1: got a pic of one?

Only in my head as yet tho I cant believe no ones actually done it before (well to my knowledge)

[woodyguy]

Ok, so made a couple of 8mm holes that didn't make much difference.

So increased to 5x 8mm holes and its great.

Revs very freely.

Tuned with a tacho and the L screw is fine.

The H screw only comes out 3/4 turn and at that it is doing 14000. Leaning the mix increases it so I left it full out.

It runs very well and doesn't bog down in the cut as it used to. So I'm happy with it.

Presumably to make it richer and tune it to the desired 13500 I'd have to remove the H stop. How do I do that and is there any need if it's happy doing 14000? Is 4 stroking nicely but then running cleanly in the cut.

Advice welcomed!!

[wisecobandit]

Personally I wouldn't panic as 13500 is a guideline and normally a 500rpm safety net on the guide. The main thing is you've tached it, your happy, and is 4 stroking so I would leave it as is.

 

Not sure what carbs on that model (zama?) but I dare say the limiters are just plastic sleeves with little tabs on that fit over the adjustment screws, its just a case of trimming the tabs off which can normally be done with side cutters nd cleaned up with a Stanley knife although im lazy and just use a dremel and sand it down..

[woodyguy]

Thanks. Useful to know. To be honest, as its running well, happy at 14000 and being a small saw, doesn't tend to run at 14000 for great lengths of time, I'll probably leave it at 3/4 turn open.

[wisecobandit]

Once its in wood it wont be at 14000 anyway.

Just a word of advice once you start to use it do a few sparkplug checks soon after and make sure the colour is good on the plug. Just a little reassurance for yourself its all hunky dory.