DIY dyno

[JanBros]

Found some free software to make a DIY dyno, so off course I had to give it a try :msn-wink:
thought this was a proper section for it, as it's like building a "buckett" dyno :)

software is here : http://www.rcgroups.com/forums/showthread.php?t=2017678

had it's first run today :


http://s201.photobucket.com/user/janbros/media/dyno2.mp4.html?o=0

not finished yet. I am using a small electric motor as inertia mass which off course isn't enough , as I do not have the space to store a large dyno :(
but it's from a forklift and I have the hydraulic pump attached to it (free from work :clap:) . still need to make some oil tubing, fit an adjustable preasure valve into the system and a small oil tank. I'm hoping I can adjust the preasure in the system in such a way, that the resitance/inertia of the motor is so that it takes about 10 seconds to get to max rpm. I don't care about the HP numbers that come out , all I want is something that can pretty accurate give me a power graph, and that I can see if my "tuning" makes it better or not.

[quallman1234]

Found some free software to make a DIY dyno, so off course I had to give it a try :msn-wink:
thought this was a proper section for it, as it's like building a "buckett" dyno :)

software is here : http://www.rcgroups.com/forums/showthread.php?t=2017678

had it's first run today :


http://s201.photobucket.com/user/janbros/media/dyno2.mp4.html?o=0

not finished yet. I am using a small electric motor as inertia mass which off course isn't enough , as I do not have the space to store a large dyno :(
but it's from a forklift and I have the hydraulic pump attached to it (free from work :clap:) . still need to make some oil tubing, fit an adjustable preasure valve into the system and a small oil tank. I'm hoping I can adjust the preasure in the system in such a way, that the resitance/inertia of the motor is so that it takes about 10 seconds to get to max rpm. I don't care about the HP numbers that come out , all I want is something that can pretty accurate give me a power graph, and that I can see if my "tuning" makes it better or not.

We use simple dyno for ours. Works great, with an arduino and a pick up coil.
We manage to get exactly the same readings for multiple pulls after the engine is warmed up.

Better Link
https://sites.google.com/site/simpledyno/file-cabinet

[quallman1234]

Videos..

https://www.youtube.com/watch?v=aXmAPHSgZXk

https://www.youtube.com/watch?v=b10wk5nIBc8

[mr bucketracer]

will post some pictures later of mine, built 3 so far , 1 motorcycle and 2 kart engine ones

[AllanB]

Very cool.

However


Mine is the best. No doubt.


The Seat of Pants Dyno.


Every time I spend lots on things like mufflers or carbon or fancy levers the SoPD tells me it was money well invested with measurable gains .......

[mr bucketracer]

320712320713 what kind are you planning on building

[mr bucketracer]

320714320715some more

[mr bucketracer]

Kart on my bike dyno��320716we are on the bottom of the world lol

[Jin]

String, skateboard, bungee cord and a pencil is what i use seems pretty accurate though ymmv

[JanBros]

got it working and started playing with preasures, and it worked - ish :-s

raising the preasure slowed down the rise of rev's, but once over 20bar, the engine wouldn't reach it's max rpm any longer. maybe the output line was too slow and limited the flow of the oil ? don't know, but it was enough to ditch the thing :bye:

So came up with another idea :shifty:
it needed to be pure inertia so there are no limits, but small and not too heavy so I can put it in a corner out of my way. So I tried a complete electric motor/reduction/drivetrain from a pallet truck or a stacker (don't know, it was lying on the shelf at work with broken mountings).
thought was : drive the traction wheel with the rear wheel of the moped, and as there are 2 reductions in the unit, the lightweight motor has some serious inertia due to it's high rev's when used in reverse. And it works like a charm :Punk:


http://nl.tinypic.com/r/2zf1kbk/9

in the middle when the rev's drop a bit, that's when the vario opens.

So now I need to have a vario in a fixed position so I can see engine improvements, and than find the best vario setup, all without having to leave my shed :woohoo:
at the end of the video, you se the other side of the electric motor, and a magnetic brake normaly goes on there, so in case of emergency, I know even have a brake 8)

[TZ350]

And it works like a charm :Punk:
http://nl.tinypic.com/r/2zf1kbk/9
So now I need to have a vario in a fixed position so I can see engine improvements, and than find the best vario setup, all without having to leave my shed :woohoo:

Great work, I love it.:niceone:

[JanBros]

spent the whole day on the dyno, getting to know it, find out how to wotk with it, and get the settings right.

first I measured the MOI (cord arround the wheel, pulley, bucket of water, ...). got a MOI of 9.78kg/m². so changed dimensions for the roller in the program to get the same MOI.
did some runs, put couldn't get any usable power figures (only like 0.00xx BHP).
so started changing dimensions/weight of the roller and finaly got a figure of about 2.5/3 BHP (moi was than about 2kg/m²).

next up : excluding the vario. blocked it in the short gearing position, but than a run lastet hardly 2 seconds
so blocked in in the longest gearing position. Only to face a new problem :( : because the clutch comes after the vario, it now spinned at a much higher rpm, making it come on at very low engine rev's. too low for the engine. Putted the stiffest clutch-springs I had in it and the engine just managed it :wari:


http://nl.tinypic.com/r/11r3qr8/9

https://www.2fast4u.be/attachment.php?attachmentid=12967&d=1463680725

very pleased with the result, now the real work can begin

:beer:

[FastFred]

http://nl.tinypic.com/r/11r3qr8/9 spent the whole day on the dyno, getting to know it, find out how to wotk with it, and get the settings right.

very pleased with the result, now the real work can begin

:beer:

Good work ... :drinknsin

[JanBros]

been playing for 2 days, me happy with the result :woohoo:
full line is result, stripes is what it was. only thing that changed : other cylinderhead and programable ignition.

about 20% more power (graphs are with vario working) and on average over 5km/h faster after x seconds 8)

http://i201.photobucket.com/albums/aa233/janbros/Sky%20MX/POWER%20VS%20RPM%2031-5-16.jpg (http://s201.photobucket.com/user/janbros/media/Sky%20MX/POWER%20VS%20RPM%2031-5-16.jpg.html)

http://i201.photobucket.com/albums/aa233/janbros/Sky%20MX/SPEED%20VS%20TIME%2031-05-16.jpg (http://s201.photobucket.com/user/janbros/media/Sky%20MX/SPEED%20VS%20TIME%2031-05-16.jpg.html)

[FastFred]

CVT, very interesting. The dyno curves are different to what I am used to seeing with geared bikes. Can you tell me what to look for in a CVT dyno curve.

[JanBros]

CVT, very interesting. The dyno curves are different to what I am used to seeing with geared bikes. Can you tell me what to look for in a CVT dyno curve.

I neither could learn something from that powergrahp http://emoticons4u.com/happy/1053.gif

I first did the engine with the CVT blocked to get the ignition right (like the graph a few psts before), tested 3 pipes but as I already thought, the one we used before was the best.

than it's setting up the CVT and clutch, and for that I don't use the power graph but only the time/speed table : the faster you get to your top speed, the better the setup is :msn-wink:

[FastFred]

Thanks, I asked because CVT is not that common in racing here, so very few have much experience with it but it looks very interesting.

[Drew]

Hmmmm, CVT transmission would kinda make its own dyno graph. The horse power number isn't relevant at all, just the wheel speed after a set length of time.

That's great for tuning if you graph the speed like is done here. Brilliant.

Edit. Oh, I see this was said in the next page already.

[JanBros]

I neither could learn something from that powergrahp http://emoticons4u.com/happy/1053.gif
thnking again about it, a good graph needs to look like a steady decline in power just like the one on top.

if for example the CVT would open too soon, you will see a sudden rise in power because the CVT will be full open before rpm of max power, so that by the time that rpm is reached, the power will also increase.

if the CVT is setup correct, it should only start to open (change gearing) at max power, and from then on keep the rev's at max power while continualy opening further.
as a result, the actual power of the engine stays the same, but the wheel/roller rpm drops. so the software will see this as a drop in power.

than again, if the CVT starts to open too late (after rpm max BHP), you might not know this from looking at the graph because the graph will show a drop in power anyway. so you'de always have too start with a CVT that opens too soon first, if you do not Dyno the engine first with a blocked CVT.

[FastFred]

Thank you for the explanation, CVT is something we are interested in trying, but first we have to understand it.

[JanBros]

Thank you for the explanation, CVT is something we are interested in trying, but first we have to understand it.


below is an answer from Frits to a question of me regarding a CVT set-up problem on Pit-Lane.biz. My problem was that from standing still everything worked perfect, but when I re-opend the throttle at low speeds (just before the clutch would release itself) after some runs up and down the street, the engine wouldn't pick up. It seemed as if the clutch gripped sooner because of heating up or something like that.

his anwser was a good explanation of how the secondary sheaves, spring and slots work together :

The slots in the secondary pulley serve to support the working of the secondary spring. The more torque that is being transmitted trough the slots, the more the secondary pulley sheaves are pushed together.
If you close the throttle, the torque diminishes and the secondary sheaves can move wider apart. The drive-belt will ride lower in the secondary pulley and higher in the primary pulley on the crankshaft. Engine rpm goes down, exactly what the ordinary customer expects when he closes the throttle.
For racing you want the engine rpm to be constantly at the value for maximum power. You can help this by applying axial slots. But axial slots will not support the working of the secondary spring at all, so you will need a heavier secondary spring in combination with those axial slots.

picture :
https://lh4.googleusercontent.com/-NFNA8NTDdrk/VAjPakmw8zI/AAAAAAAAAUc/bjDBs6Pt6P4/w640-h480-no/vario1.JPG

[oldjohnno]

I built this a few months ago and thought some of you blokes might be interested. The dyno is extremely simple, primitive even. But it works very well, is accurate and repeatable. The only downside is that it doesn't give a direct hp reading, you have to work it out from the rpms and torque reading. I have a spreadsheet set up so that all I have to do is punch those two numbers in and it spits out the hp figure, corrected for current weather conditions.

The absorbing element is a bloody big ventilated disc brake, 380mm and 15kg, so it's bigger than a Chev flywheel and twice as heavy. It's mounted on a hub that spins on needle bearings around the spindle. The caliper is free to rotate around the spindle too, and is only restrained by a torque arm exactly 12" long that is connected via a cable to the torque gauge. This gauge is just a dial type spring scale, just like those of the older mechanical dynos. If you wanted to get fancy a load cell would work just as well.

I used this style instead of an inertia style because I wanted to be able to run at full load for an extended period, something an inertia dyno can't do. I need to know that the engine is going to survive an extended full throttle run without seizing or holing the piston.I also didn't want to deal with the inconsistencies that go with a tyre on a roller. The absorbed energy is converted to heat, just like any other dyno. With short runs - say 10 seconds or so - I don't even have to run a blower on the brake, I just let it spin a bit in top gear and the natural circulation of air through the disc is enough. For longer runs and higher power levels I direct an air blower into the "inside" of the disc, and this allows it to run loaded indefinitely. But for normal tuning work, by the time I've changed the jets or timing or whatever it's good to go again. It's never been hot enough to even turn bluish yet, though it's only had to deal with around 55hp. The only thing I might do is put a shroud around the brake so I can direct the hot air outside where it won't affect the engine output. Because of the bikes overall gear ratio the rear hub never sees more than about 2000rpms so I don't have to worry about it bursting. You certainly wouldn't want to try running the iron disc at anything approaching engine speeds though...

But like I said, it works very well, cost under 2k and took a couple of half-arsed weekends to build.

http://www.oldjohnno.id.au/images/dyn.jpg

http://www.oldjohnno.id.au/images/dyn1.jpg

http://www.oldjohnno.id.au/images/dyno2.jpg

[FastFred]

Looks really good. .... :niceone:

[FastFred]

below is an answer from Frits to a question of me regarding a CVT set-up problem on Pit-Lane.biz.

picture :
https://lh4.googleusercontent.com/-NFNA8NTDdrk/VAjPakmw8zI/AAAAAAAAAUc/bjDBs6Pt6P4/w640-h480-no/vario1.JPG

Thank you for the picture and explanation.

[cotswold]

i will be picking your brains re a race CVT, you have been warned


The slots in the secondary pulley serve to support the working of the secondary spring. The more torque that is being transmitted trough the slots, the more the secondary pulley sheaves are pushed together.
If you close the throttle, the torque diminishes and the secondary sheaves can move wider apart. The drive-belt will ride lower in the secondary pulley and higher in the primary pulley on the crankshaft. Engine rpm goes down, exactly what the ordinary customer expects when he closes the throttle.
For racing you want the engine rpm to be constantly at the value for maximum power. You can help this by applying axial slots. But axial slots will not support the working of the secondary spring at all, so you will need a heavier secondary spring in combination with those axial slots.

[husaberg]

there are some good post from around these pages
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page643?p=1130438278#post1130438278

[Pumba]

Here we go Dyno geeks. Just popped up on my on of the buy/sell groups I follow on FB. Set up for karts but thought it was cool.

https://scontent.fakl1-1.fna.fbcdn.net/v/t1.0-9/14937400_1177943702298951_7353968567270586692_n.jp g?oh=d6e33e50d49cf8abf45bd006bccdd482&oe=58962249

http://www.ebay.com/itm/272435674993?ssPageName=STRK%3AMESELX%3AIT&_trksid=p3984.m1555.l2649

[Bert]

Here we go Dyno geeks. Just popped up on my on of the buy/sell groups I follow on FB. Set up for karts but thought it was cool.

https://scontent.fakl1-1.fna.fbcdn.net/v/t1.0-9/14937400_1177943702298951_7353968567270586692_n.jp g?oh=d6e33e50d49cf8abf45bd006bccdd482&oe=58962249

http://www.ebay.com/itm/272435674993?ssPageName=STRK%3AMESELX%3AIT&_trksid=p3984.m1555.l2649

Ouch... not cheap...

[Pumba]

Ouch... not cheap...

Haha, never said it was. Quality bit of kit though.


Sent from my iPhone using Tapatalk

[husaberg]

https://www.youtube.com/watch?v=-6PQrmvxrfY
https://www.youtube.com/watch?v=gv95EJ6VzVU

[jfn2]

I'm planning to build a bike dyno and I need to come up with a size (inertia wise) for the roller wheel. I want to be able to dyno a 150 hp bike.
thanks, jfn2

[speedpro]

I ran my bike on a Dynajet 150 I think it was and it was OK. 175hp. If you can find what their setup is it'd be a good start. If I remember correctly we spun the roller to something like 130mph in 3rd gear

[TZ350]

The DynoJet has a number on the drum, not sure what it means, inertial weight maybe because it was part of the information needed when installing updated software. I will take a photo tomorrow.

[TZ350]

329821329822

DynoJet 150
Drum Mass 13.82
Drum Circumference 4.67

I have no idea if the units are in Kg's meters lbs feet or good old American slugs and ergs. Google - US common system of units.

[mr bucketracer]

329821329822

DynoJet 150
Drum Mass 13.82
Drum Circumference 4.67

I have no idea if the units are in Kg's meters lbs feet or good old American slugs and ergs. See US common system of units.im shore my dyno jet was lined in lead

[speedpro]

What software is anyone using on a home built inertial dyno?

[jfn2]

I'll be using the Performance Trends Datamite system.

[mr bucketracer]

I'll be using the Performance Trends Datamite system.same here..

[jfn2]

I believe 4.67 is in feet and the 13.82 is in kg/m*2. The new DynoJet roller seems to work out very close to those numbers.

[Moooools]

329821329822

DynoJet 150
Drum Mass 13.82
Drum Circumference 4.67

I have no idea if the units are in Kg's meters lbs feet or good old American slugs and ergs. Google - US common system of units.

A bit of napkin math suggests that I/r^2 (Inertia/(radius of drum squared)) would be equal to about 1.5x the mass of the bike to achieve accelerations similar to on track in each gear.

That would suggest that a bucket would accelerate about 3 times faster in each gear on the dynojet compared to the track. Does that sound about right from your experience TZ or way off the mark?

[TZ350]

Yes I agree with you, they do seem to accelerate quite a bit quicker on the dyno than the track.

[jfn2]

Moooools:
My bike with me on it weights 548.5 kg. Lets say that in top gear it takes me 10 secs to accelerate on the track. Using your equation ( I know it's right) I come up with 28 kg/m*2 with a .457m dia roller. Using TZ350's dynojet number of 13.82 kg/m*2 and a dia of .457m (which I also think is right) I need roughly twice the kg/m*2 to get the same acceleration. So I need to be turning 2 rollers like the dynojet one. If TZ350's dynojet roller measures somewhere around .406m long I'll need one around .816m long. Am I correct? Thanks

[Sketchy_Racer]

I'm selling up as we've bought a section and got to move house, so for sale is my beloved dyno.

It's a humble little inertia chassis dyno that was designed for doing bucket bikes, it has since been used for tuning many bikes, including a lap record setting NSR300.

It comes with everything ready to go minus laptop for screen (or can include for addition $200). That includes cooling fans and exhaust extraction as well as data acquisition module.

if you are interested I can arrange getting some photos and techinical specs sent though.

As for price i'm not sure, if you're interested get in touch 022-089-3234 or G.skachill@gmail.com

Cheers,
Glen

[jonny quest]

Looking for recommendations on a manual hydraulic brake master cylinder for inertia drum braking. 900lb drum.

Going to use a car disk and caliper, but having a hard time sourcing a master cylinder that offers fairly easy mounting and isn't vacuum assist

[Grumph]

Outside the US there are still a lot of British Lockheed non assisted brake masters in scrapyards.

Inside the US, I'd look at aftermarket race car stuff - Wilwood probably. Dirt car applications would be a good starting place.

[speedpro]

Looking for recommendations on a manual hydraulic brake master cylinder for inertia drum braking. 900lb drum.

Going to use a car disk and caliper, but having a hard time sourcing a master cylinder that offers fairly easy mounting and isn't vacuum assist

I used a trailer brake master cylinder and made a bracket with a 1m lever. Cheap as chips and works fine on my rolling road. Rotors and calipers can be had from a car compliance business in NZ for free. I got a 4-pot new-looking Brembo out of a bin

[speedpro]

photos of spare cylinder I used

[jonny quest]

Thank you!

[husaberg]

Outside the US there are still a lot of British Lockheed non assisted brake masters in scrapyards.

Inside the US, I'd look at aftermarket race car stuff - Wilwood probably. Dirt car applications would be a good starting place.

https://www.amazon.com/GIRLING-STYLE-ALUMINUM-CLUTCH-CYLINDER-GIRLING/dp/B00RKGF1QK
http://www.zeppy.io/discover/us/girling-master-cylinder