DYNO eddy current brake. take 2!

[keatonx]

Here's a dyno I built a month ago to prove a power increase from one of my 2 stroke design mods-





Rm125 bottom end. Think you get the idea. Weed eater shaft fits over the square on the impeller side, clutch slip is adjusted with that adjustable clutch arm to adjust rpm, the fishing scale on the end of the torque arm (which is welded to the primary gearshaft) reads in ft. Lbs. Everything runs dry on the inside. Took 4-5hrs total of building and messing with to get it working right.

For rpm there's an iphone app called "engine rpm", costs $8.99 but works fine if you know how to work it. It uses the engine sound. I started using a laser tach later on tho.

I made a few inertia dynos too, they all were super dangerous and I didn't want a big piece of metal flying off at 12000rpm.

 

[HeadSmess]

^^^^ your weldings looking nicer should do the job. wet clutch? will help get some heat away from it

currently sidetracking... i got leaking roofs in need of rebuilds taking precedence!

 

[HeadSmess]

I dont always just talk

finally. today...well, lets say, i had the urge. the itch!

i apologise to all and one and none and whatever for taking so long...




so, the theory actually worked. im impressed myself...

theres a fair bit of momentum building up in that disc first time i spun it up it caught me out...

anyway. make a nice bench and bore out that lovejoy coupling on the drill to fit the ht crank.

lovejoy couplings...i got a few hiding somewhere...( i just realized where! ahuh!)


this isnt just for the ht, of course

a dyno is born. all for about hmmm...the magnets are the biggest cost...100 bucks total say cheering.

oh yeah. it needs balancing...

read this plois

http://www.rcgroups.com/forums/showthread.php?t=1267814

 

[HeadSmess]

few pics..







i didnt break one tool despite my speed control going haywire!

something else to fix now it never ends

 

[HeadSmess]

latest update.... i fixed my bandsaw so its cutting straight again. why the **** do they put shielded bearings on the guides that get full of grit, and sealed ones where it remains clean? grrr.

so, out with the welder! and some handy council road work stands note the close proximity of that jerry can to the welding, erm...bay...



the idea behind this stand is to be useable on other engines, so now its time to hack up an old frame for the V, and make a nice bracket so engine will line up like thus...



starting will be fun! i think just the old "rope on a pulley" will suffice.


hey! thats the first HT engine i ever bought, right there! must be nearing six years now! why havent i melted it down yet? cus the case comes in handy at times, i guess.

 

[Fabian]

That jig is looking impressive.
I can't wait to see the engine running flat out with various cylinder heads and ignition systems and induction systems and exhaust systems and mechanical alterations to see what's giving the best numbers on the dyno

 

[HeadSmess]

its the ugly duckling! but far nicer to work on than in a bike frame...this thing simply CANT spin round and whack me in the head with a handlebar!

not juuuust flat out gunna be some low speed tests too!

well, i got to the point of firing an engine up...




i think...yes, im sure now... i took that pic AFTER the slight failure...

this ones definitely after



i had a vague feeling that these cast iron (small as well) flexible couplings were a bad idea! oh well, one uses what one has lying around and suffers the consequences....


well, for my first attempt at cutting a keyway, it worked pretty well

and the engine fired up! just not while the camera was recording inch: murphy must be taking a break for once? hes had a busy day so far!

surprising really.

thats it... for probably the next six weeks. i got a boat to build tomorrow! yeah....i do it backwards. i got an engine that needs a boat. normally its the other way round?

 

[Fabian]

I like the progress reports. Can't wait for the video of different performance combinations being tested, or even different standard items being tested.

 

[HeadSmess]

new cush drive



the shaft is tapered. i never noticed that before!

getting tapers spot on is enough to make one cry. got there in the end



blat blat blat...

 

[Fabian]

Can't wait for the calibration to be completed so we can start seeing some real power numbers.