chainsaw ?regulator?

Post by **parrot** » May 31, 2016, 6:28 pm

I bought a chainsaw today at one of the home supply stores. While assembling it for me, the tech asked if I wanted it to be stronger than normal? I told him yes......and before he attached the bar and chain, he removed what I believe is muffler of sorts and then took off the item in the photo below. He told me if would have no ill-effect on the motor.
So that has me wondering what this small item does...exactly. My main concern is no doing any unnecessary damage to the engine. Can anyone out there clue me in? (I'm the equivalent of John Sutherland.....'Zen and the Art of Motorcycle Maintenance'.......I don't care much about how it's done.....just do it).

Post by **FrazeeDK** » May 31, 2016, 6:49 pm

2 stroke engine?? perhaps the piece is to maintain a certain level of back pressure within the cylinder.... I would take with a grain of salt sales people in the mega stores claiming they know what they're doing...

Post by **macca46** » May 31, 2016, 6:54 pm

An un- educated guess it could be a baffle plate that would cut down on noise and also restrict power?

Post by **fatbob** » May 31, 2016, 6:54 pm

What sort of chainsaw is it? Bottom line is doe's the Thai sales rep know more than the chainsaw manufacturer, he thinks he doe's but I doubt it!

Post by **parrot** » May 31, 2016, 7:39 pm

It's a 2 stroke.....and a baffle plate seems to fit the description......and there are links like the one at http://www.ebay.com/gds/How-to-Modify-a ... 173/g.html that seem to apply.

As the guy at the shop told me, 'you can always put it back on easily enough'.........and with that, I'll probably do some test cuts tomorrow to see if there's a visible difference.

In the meantime, I don't want to do something that increases the already high danger risk of using a chainsaw. Any knowledgeable inputs welcome.

Post by **Stevo** » May 31, 2016, 8:41 pm

It's a 'Restrictor' plate, parrot...
When fitted, it restricts the flow of exhaust gases therefor capping the RPM of the motor.
Here's a pic of a similar item used by Evinrude/Johnson in their small 2 cyl outboard motors...
when fitted it reduces the power of the 15 HP model to 9.9 HP.

Post by **parrot** » May 31, 2016, 8:54 pm

Stevo wrote:It's a 'Restrictor' plate, parrot...
When fitted, it restricts the flow of exhaust gases therefor capping the RPM of the motor.
Here's a pic of a similar item used by Evinrude/Johnson in their small 2 cyl outboard motors...
when fitted it reduces the power of the 15 HP model to 9.9 HP.

GT10 restictor.JPG

Thanks..........so, that leaves me, John 'clueless' Sutherland, wondering why they would do such a thing. One of the other stores I check had 3 very similar looking chainsaws, a few hundred baht different between each model. I inquired. The salesman said, each was a slightly different horsepower. Why would you want to reduce a 15HP model to 9.9? Just wondering.

Post by **Stevo** » May 31, 2016, 9:16 pm

parrot wrote:Why would you want to reduce a 15HP model to 9.9? Just wondering.

As far as outboard motors are concerned... mainly, 'Competition regulations' i.e. If a certain type of boat race has a limit of 10HP motors which can be used, why redesign one from scratch when it's so simple to restrict a slightly more powerful model already in your line-up.
In the UK, 50cc motorcycles were restricted to 30MPH in a similar way... Yamaha (as an example) welded a washer inside the top of the exhaust downpipe, which capped RPM, thus reducing top speed. They did a similar job with some 125cc machines which were restricted by law to 12 BHP.
Import taxes could also be a factor in some countries.
On a chainsaw... I would imagine it has been done for either engine longevity, or perhaps the standard chain cannot cope with higher RPM (safety reasons).

Post by **noosard** » June 1, 2016, 7:46 am

In the meantime, I don't want to do something that increases the already high danger risk of using a chainsaw. Any knowledgeable inputs welcome.

Keep the sharp end away from ones self
Pays to keep two hands on the machine
Keep blade sharp as works better and is safer
Ideally you would have head protection including ear muffs and visor
Leather apron and work boots
Try not to use the tip for cutting as it can/will cause the machine to flick towards you

Post by **FrazeeDK** » June 1, 2016, 8:58 am

OK... restricts RPM... So, you'd have to wonder if the chain spinning above a certain RPM becomes dangerous... That would make it a safety issue and we know that Thais and Safety don't always mix well.. Kinda like taking safety covers off weed wackers, lawn mowers or riding motorcycles without a helmet... Or, like my nephew, using a lawn mower wearing flip flops which ended up costing him a big toe!

Post by **Barney** » June 1, 2016, 9:16 am

Good to see a post with informative answers especially Stevo's mechanical knowledge.

Parrot you should have the owners manual to advise, it may even show all the motor parts in a diagram?

I'm no mechanic and that's been proven many times, but perhaps Stevo could answer, if you take out any restrictor to increase the exhaust outlet to provide more speed or power would you not have to adjust the fuel , like running to lean or rich, and not just take out a mechanical restriction orifice?

Others with safety tip are absolutely correct. Correct PPE and keeping all guards in place are paramount.

Post by **12345** » June 1, 2016, 9:23 am

Yes Parrot, please report back with test results, as curious if removal may increase cutting efficiency.

Mine leaves a bit to be desired on occasion.

As always to the others, well, never pass up an opportunity to bash the locals.

1. I would take with a grain of salt sales people in the mega stores claiming they know what they're doing...

2. Bottom line is doe's the Thai sales rep know more than the chainsaw manufacturer, he thinks he doe's but I doubt it!

3. we know that Thais and Safety don't always mix well.

Thais and safety vs foreigner and safety. I personally don't know the names of any Thais who have died in scooter accidents because of not wearing a helmet. But every foreigner I know who has died from an oops on a scooter, was not wearing a helmet. About 5 so far, and considering I know many more Thais than locals..........well, nuff said.

Post by **parrot** » June 1, 2016, 9:45 am

Barney wrote: I'm no mechanic and that's been proven many times, but perhaps Stevo could answer, if you take out any restrictor to increase the exhaust outlet to provide more speed or power would you not have to adjust the fuel , like running to lean or rich, and not just take out a mechanical restriction orifice?

Yes, the guy had fine tuned the carb before asking me if I wanted the high performance tuneup. Once he removed the baffle, he restarted the engine and readjusted the carb. I did a few test cuts this morning, about half throttle, 6 inch diameter wood, cut right through.

I did ask the guy about any negatives to removing the baffle. He said the only negative was that the engine would use more gas.

I'm almost tempted to go back to the store that had 3 Models that looked exactly alike.......a few hundred baht different in price.......and a fraction of a hp higher with each price increase........and dissect the models to see what caused that increase.

Post by **12345** » June 1, 2016, 9:54 am

parrot wrote:Yes, the guy had fine tuned the carb before asking me if I wanted the high performance tuneup. Once he removed the baffle, he restarted the engine and readjusted the carb. I did a few test cuts this morning, about half throttle, 6 inch diameter wood, cut right through.

Was wondering about the carb adjustments, as when buds of mine took baffles out and or modded their Harleys, major carb air/fuel intakes had to be adjusted. So the sales / tech rep obviously knew his stuff. That can be hit and miss at times, mostly hit though, as impressed with reps I've dealt with and have learned a thing or two.

Thanks for the performance review. Next time I take it in for a tune up, may make do the remove and adjustments.

Play safe.

Post by **rick** » June 1, 2016, 10:16 am

I think the power restriction is to limit deforestation - i did read some time ago that you need a permit for chainsaws above a certain length of blade, could be a Horsepower restriction as well. Then manufacturers make these adjustments to a standard model to suit the Thai market. Obviously the impact this has on illegal tree felling is probably minute, and like selling guns which have been modified to make them not work, easily reversed.

Post by **12345** » June 1, 2016, 10:25 am

They seemed to have eased up on the restriction or enforcement of chainsaws, as don't remember seeing them, retail, until about 5 yrs ago, and only 12 inch bars.

Law also being a bit vague on registering 12 inch or not, so do check with you local Police, to see if they mind, if rural, as they'll be the ones to stop by. Hefty fine it is, so stay close to home when using if not registered.

Post by **parrot** » June 1, 2016, 10:59 am

According to the Forestry Dept, under 2hp, not more than 12" bar, no permit required. Inside the English owner's manual is a letter, in Thai, from Sripatum University (มหาวิทยาลัยศรีปทุม) verifying the chainsaw's specs.
I bought my first chainsaw over 4 years ago......I can remember the first time I saw one for sale about a year before that, it was a big deal as you couldn't buy one for the first 14 or so years I was here. Global had a Hitachi for about 8k and the Tuf for around 3k. I decided to go cheap.....and didn't regret it. Take care of it, keep it oiled and the chain sharp, and don't try to cut huge trees.........they should hold up fine.