The ol shoulder doesn't hurt running the saw but I pay the next day if I swing the maul much anymore. Running the saw is more funner.
400c Rumors… or just internet trolls.
- Thread starter JKendrick87
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A dyno is the fairest method to use. Assuming it's a legit dyno will a full compliment of sensors in place and a competent operator.
DittoThe ol shoulder doesn't hurt running the saw but I pay the next day if I swing the maul much anymore. Running the saw is more funner.
I gotta dyno in my head and hands. It's not very accurate but always works fine plus it's portable
I have seen enough cycles & sleds dyno'd never seen a saw done lol .I gotta dyno in my head and hands. It's not very accurate but always works fine plus it's portable
Do they run on the track or off the clutch directly?I have seen enough cycles & sleds dyno'd never seen a saw done lol .
I'd imagine 30% driveline loses in those.
The dyno just tells the torque and computed hp. It doesn’t really tell which saw will cut faster.I have seen enough cycles & sleds dyno'd never seen a saw done lol .
@Red97 has the chainsaw dyno stuff down pat. Folks send him saws to test all the time. https://worksaws.com/
Our local kart guy would dyno the stock appearing kart motors.
Like he told me got to have a dyno that is right on the mark and base set and tested to known stock. Some read high some low. Lot more to it then just putting on a dyno.
Our local kart guy would dyno the stock appearing kart motors.
Like he told me got to have a dyno that is right on the mark and base set and tested to known stock. Some read high some low. Lot more to it then just putting on a dyno.
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I'd have to agree with that 1,000% because most people look at Peak numbers they don't understand how to read it across the board. Show me a pancake and I'll show you some **** that checks out.
High or low is an environmental condition change from shop to shop mostly. All are know factors and never an issue if you stick with the same machine or adjust accordingly. In the grand scheme of things you're looking for power under the "usable" curve. Everything else is just numbers. Please tell us how he sees it. Numbers don't lie but like people, machines can and do. Being consistent about environment and temps separates the amateur from the pro. If you DO NOT have an in-depth weather station your readings are not consistent to adjust according. Plus altitude or is that a fairytale bit? Many have no idea.
Does he infact make corrections or is that just too hard?
I'm real curious what season turns out the highest horsepower saws there?
This is a nice can of worms to open up and see what is inside.
Please continue
Any meaningful results on a dyno are done in a temperature controlled environment. The dyno room at the machine shop had its own hvac system, as well as a full "weather station" however outside temp/humidity didn't matter. It was always 72*f and 30% humidity. Base lines are kind hard to screw up, the load cells just don't go out of whack for no reason, and was easily spotted by the operator if something wasnt adding up. Braking action was always consistent as the brake fluid was temperature controlled as well. There's zero real world reason why 2 different dynos shouldn't show very close to the same results. You could most definatly tell which chainsaw will cut the best, it takes all the bs out of the equation no chain sharpness, wood density, digging in the spikes etc. The power curve vs rpm will give a very good indication of how it will preform vs other engines. Same with any other engine. Take as many variables away, account or control all the others and the results will speak for themselves.
The automotive companies have dynos like this, but other than that they are pretty uncommon. To make results valid correction factors are used and a dyno is only as good as its operator.
As a result dyno results are mostly of value for tuning over the course of a a few days. Or for doing a comparison with multiple motors the same day. Even then it's not the exact science people think they are. It's really just a data point.
The other thing is often motors can look great on a dyno, but in the real world fall on their face. How many guys selling chainsaw porting over port them and end up with screamers that most certainly would make nice peak numbers, but fall on their face in the cut? I woukd wager that there are many.
Only way to know for certain is to try it for yourself. You’ll probably be surprised at the results
Doubtful, I've dynoed hundreds if not thousands of engines at this point. Any human intervention in testing leads to screw ups, hence why we try to remove our influence as much as possibly. Timed cuts is saws is a very vauge way to determine which one is more powerful.
No doubt, go look at the hp and torque curve of that engine. High rpm doesn't mean it makes meaningful power, and it can be seen on a dyno very easily. A engine that doesn't have a nice torque curve, peeks and or drops off early no matter if it make more peek hp than another engine won't preform as well as the engine that gets into its torque curve quickly and maintains it throughout the working rpm range. Hp is only one thing you look at and I'd argue it's much less important then the torque curve.
Very true.
Exactly Kevin . All the Dyno's I have seen are engine Dyno's or Chassis Dyno's for that exact reason . Cycles or sleds have Chassis & Suspension components that effect & can affect the final net horsepower & torgue figures , along with real time performance on the track or the trail . When I was racing for Polaris the Engine Dyno was in the Engineering Shop , while the Chassis Dyno was located within the suspension / chassis development shop . The Cycle Engineering Shops I have visited were pretty much the same with various clutching & suspension & driveline components being switch out to dial in the chassis to the engine rpm requirements . Much like how a simple b & c ( semi chisel or full chisel ) or round grind vs a aggressive square grind will affect a saw . The torgue prerequisite on a Milling saw vs a Felling saw requirement is apples & oranges . A balanced engine is what I like in a properly ported saw .. No use in having peak horsepower if the saw falls on its face within the cut .The 7900 you just did for me fills that balanced niche very well brother !
Both actually . The Engine Dyno's are driven of a jackshaft connected directly to the crankshaft on sleds . The chassis Dyno's are run similar to the cycle Chassis Dyno's , or Auto Dyno's where the sled is strapped down onto the dyno roller . I have seen some composite chassis Dyno's also utilize the jackshaft connection also with the engine mounted into the chassis for real world performance testing , to enable more precise ( cause & affect) header & jetting & clutching testing ! The most sophisticated was at Kawasaki Midwest Engineering in Wisconsin . When I was there they were dyno testing their current yr. Factory Modified Thunder Jets engines & titanium chassis for Jim Adema for the upcoming Inaugral Sno-Pro racing season . I would assume diagnostic dyno testing has evolved significantly , since then !
Dyno good for showing changes made and what gains or losses made. Long as same dyno used. Cant compare a saw from one dyno to another dyno and say mine got more power.
Like kart dyno guy said again. He had guy huff and puff my SA made 22hp on so and so's dyno one day.
My guys dyno showed 18hp. He said his is calibrated to known engines. Then you got to take in fact the weather etc.
Was amazing the difference in our hot motor and slower dependable motor.
Boy and then talk about carb modding the difference that can make.
Like kart dyno guy said again. He had guy huff and puff my SA made 22hp on so and so's dyno one day.
My guys dyno showed 18hp. He said his is calibrated to known engines. Then you got to take in fact the weather etc.
Was amazing the difference in our hot motor and slower dependable motor.
Boy and then talk about carb modding the difference that can make.
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