ESE's works engine tuner

[SwePatrick]

Thanks SwePatrick for the good pics and info on your dyno. Looks like it will turn out very nice. Did you weight the roller after you filled it with concrete and did it figure out for the right numbers with the concrete inside? If I may ask what numbers did you come up with and how large of an bike/engine can you use with just the roller. I also have the performancetrends datamite setup. But I have mine on a water brake dyno now but want to change to a inertia dyno soon. Nice feature about being able to use roller rpm right in the program. What setup did you get from performancetrends for measuring rpms. Because they have different ones available. Nice work.

Thanks
It´s actually calculated weight, you measure all dimensions and add them into datamite.
And as the concrete is just about the same density as aluminium i have given the data in aluminium for the concrete, i have rounded it downwards, actually i have rounded all measurements downwards so it won´t give me a 'happy dyno'.
The total weight of my roller including the brake is 305kg´s
But it´s actually unimportant, the important is where the kg´s are located.
To get high inertia you want it as close to outer diam as possible.
I use rare earth magnets(4pcs) and a sensor to pick them up when rotating.
This is a area to get careful in, just minor difference in distance between magnets will cause funny rpm readings.
Must be machined if you can´t get it 100% correct by hand

And to return to weight again, i have put it on a scale, and it said 307,3kgs
And calculated weight in Datamite is 305kgs(converted from pound)

And for my dynopulls with my racer, i still need to make a coastdown on the roller without the bike.
And measure the time on that, it will give me the dyno´s own frictionlosses(a parameter one need to fill in)
This actually, as is in this point gives me low readings from the bike.
My 62.16hp(64.71hp corr) actually is a bit low, but it´s about ~1-2hp low(in high rpm´s) from earlier experiances from my earlier dyno(engine dyno)

Rgds
Patrick

[WilDun]

That roller looks like (and I'm just guessing) it would be spinning at twice the revs of the rear wheel, so will balance come into the equation ?
If it does need to be balanced (I think it might) I just wondered how you would go about balancing a large long tube filled with concrete!

[SwePatrick]

Well,, first things first.
The concrete i used doesn´t contain large rocks.
It´s more like 2-3mm big 'rocks'.
And i blended the concrete 'low on water'. thereby when filling the tube the small rocks didn't 'fall out' and landed at the bottom.
I had the tube standing up when filling.
And when 'burning' the concrete increases in volume by ~2%
So it fills tube nicely after i vibrated it a bit to get air out.

Second, i have run the roller at 2600rpm as of today, no vibrations(this tells me i can rev it further).
And i have just balanced it roughly by heating the bearings to get lower resistance from grease in the bearings.
And then just added material(about 300g, not much at all actually) at the point that was always straight upwards when the roller stopped when i spun it by hand.
This gives me only static balancing, i know.
But it gives me a clue where to add or retract weight if it starts to vibrate on higher rpm´s.

And lastly, This spring i will when i take it apart for painting, I´ll go to a friend of mine that has a engineshop.
He owns a crankbalancingmachine(for different car/truck crankshafts) that can take my roller with ease.

So, i can´t see any problems with concrete...

[mr bucketracer]

Well,, first things first.
The concrete i used doesn´t contain large rocks.
It´s more like 2-3mm big 'rocks'.
And i blended the concrete 'low on water'. thereby when filling the tube the small rocks didn't 'fall out' and landed at the bottom.
I had the tube standing up when filling.
And when 'burning' the concrete increases in volume by ~2%
So it fills tube nicely after i vibrated it a bit to get air out.

Second, i have run the roller at 2600rpm as of today, no vibrations(this tells me i can rev it further).
And i have just balanced it roughly by heating the bearings to get lower resistance from grease in the bearings.
And then just added material(about 300g, not much at all actually) at the point that was always straight upwards when the roller stopped when i spun it by hand.
This gives me only static balancing, i know.
But it gives me a clue where to add or retract weight if it starts to vibrate on higher rpm´s.

And lastly, This spring i will when i take it apart for painting, I´ll go to a friend of mine that has a engineshop.
He owns a crankbalancingmachine(for different car/truck crankshafts) that can take my roller with ease.

So, i can´t see any problems with concrete...

that worked good then SwePatrick , was a bit worryed it may not work out with out to much weight added , i was going to make mine the same at the start then thought iron sand with glue mixed with it , ended up machineing a 500kg piece of steel ,

[mr bucketracer]

when near finshed

[Frits Overmars]

i was going to make mine the same at the start then thought iron sand with glue mixed with it

Bucketracer's remark made me decide to react after all. At first I did not want to spoil the party, but when others start thinking of building their flywheels the same way, I feel I must speak up. I'm not trying to be friendly today, I'm trying to avoid accidents.

The roller i use is a heavy steeltube... 300mm diam and 870mm long. It´s filled with concrete... that actually increases in volume when hardening.

So your steel tube is already pre-tensed by the concrete that is trying to expand, even before centrifugal forces set in.
That concrete may have about the same specific density as aluminium, but it has nowhere near the same tension strenght.
In other words: it won't be able to keep itself together.

Milling grooves to help traction

Those grooves also reduce the steel tube's effective wall thickness, so the centrifugal forces will have an even better chance of creating havoc.

i have run the roller at 2600rpm as of today, no vibrations (this tells me i can rev it further).

Does it also tell you how much further before it explodes?

I will also add some protection around roller and flywheel.

That's a good idea. A bunker would be nice; it's concrete might just be able to contain your concrete (better being sarcastic now than sorry afterwards).

I´ll go to a friend of mine that has an engine shop. He owns a crank balancing machine... So, i can´t see any problems with concrete.

I hope your friend can, before he revs it any higher than you have done. With your 62 rear wheel-HP you can easily do 200km/h on the street and if you try to approach that on the dyno, your 300 mm roll will be doing 3536 rpm...

i have just balanced it roughly by heating the bearings to get lower resistance from grease in the bearings.

The bearing seals will probably cause a lot more friction than the grease. But seals do not take kindly to being heated. It's better to just run them in with moderate revs until their friction has stabilized. And then you can help balancing by putting a vibrator (not the kind that Adegnes used as a porting tool, but the real deal that is used by roadworkers) on the dyno frame. It will make your flywheel dance in its bearings, greatly reducing friction.

[SwePatrick]

Bucketracer's remark made me decide to react after all. At first I did not want to spoil the party, but when others start thinking of building their flywheels the same way, I feel I must speak up. I'm not trying to be friendly today, I'm trying to avoid accidents.

So your steel tube is already pre-tensed by the concrete that is trying to expand, even before centrifugal forces set in.
That concrete may have about the same specific density as aluminium, but it has nowhere near the same tension strenght.
In other words: it won't be able to keep itself together.

Those grooves also reduce the steel tube's effective wall thickness, so the centrifugal forces will have an even better chance of creating havoc.

Does it also tell you how much further before it explodes?

That's a good idea. A bunker would be nice; it's concrete might just be able to contain your concrete (better being sarcastic now than sorry afterwards).

I hope your friend can, before he revs it any higher than you have done. With your 62 rear wheel-HP you can easily do 200km/h on the street and if you try to approach that on the dyno, your 300 mm roll will be doing 3536 rpm...

The bearing seals will probably cause a lot more friction than the grease. But seals do not take kindly to being heated. It's better to just run them in with moderate revs until their friction has stabilized. And then you can help balancing by putting a vibrator (not the kind that Adegnes used as a porting tool, but the real deal that is used by roadworkers) on the dyno frame. It will make your flywheel dance in its bearings, greatly reducing friction.

Wow Frits!
That was a lot of guesswork and negativity from you today.
Do you think my tube is equipped with ~5mm thickness?
Let me just say,, ,it´s not.

[SwePatrick]

that worked good then SwePatrick , was a bit worryed it may not work out with out to much weight added , i was going to make mine the same at the start then thought iron sand with glue mixed with it , ended up machineing a 500kg piece of steel ,

Been calculating a lot on centrifugal forces, and even if Frits are negative so am i very positive, as i have worked with concrete earlier in my jobcarrier and know some stuff that some might not
My tube is quite 'thickwalled', and won´t explode at 200km/h that i have set at maximum speed before balanced it properly.

Rgds
Patrick

[SwePatrick]

when near finshed

Looking good.
I used more spacing between grooves thou.
It might shred sticky tires if having them 'side by side'.
Keep an eye on that

rgds.

[speedpro]

I would have thought a mirror polished surface would have been better than grooves, something the rubber can adhere to. After all, in a tyre it isn't the tread that grips the road but the rubber, hence slicks for racing.

[WilDun]

Looking good.
I used more spacing between grooves thou.
It might shred sticky tires if having them 'side by side'.
Keep an eye on that

rgds.

Patrick I think Frits is only being cautious (not negative and not wanting to see you splattered on the walls and ceiling) no harm in that? - Lets just call it "positive negativity"

[mr bucketracer]

Looking good.
I used more spacing between grooves thou.
It might shred sticky tires if having them 'side by side'.
Keep an eye on that

rgds.

i knurled it like a dyno jet roller , at least 10 hours work to do lol .

[SwePatrick]

Patrick I think Frits is only being cautious (not negative and not wanting to see you splattered on the walls and ceiling) no harm in that? - Lets just call it "positive negativity"

Yes.. but there are better ways to get people to listen.
Negativity either good or bad,, makes me just think the person is a.... 'wellwhateveryouwannacallit'.
If using some competence in handling people one can ask leading questions and then lead the person in the directions one want them to go.
In this case Frits vomits negativity all over me, all before he actually knows anything about my design.
That´s just lame if you ask me, and all flavoured in dictatorship.

Rgds

[SwePatrick]

i knurled it like a dyno jet roller , at least 10 hours work to do lol .

Hehe,, took me 12hrs to mill the roller for me *lol*
Had to go slow as this was about absolute maximum my old mill could take.

Rgds

[SwePatrick]

I would have thought a mirror polished surface would have been better than grooves, something the rubber can adhere to. After all, in a tyre it isn't the tread that grips the road but the rubber, hence slicks for racing.

Actually no, you want ridges to have the rubber being able to 'grab' something.
Many people have been using polished rollers, and they all seem to have problems with traction.
This results in having the bike/car strapped down really hard, deforming the tires a lot.
And that is really dangerous.
And gives you erratic numbers as the tire takes a lot of power in the process.
I did a fast test before i did any full pulls.
I was carefully to begin with so i strapped my bike quite hard.
I lost about 10hp, i made more pulls and strapped the bike looser and looser.
And finally figured out i didn´t need to strap the bike downwards at all.
I just strap it on front wheel and in sideways at rear wheel.
I need to sit in the seat ofcourse to make 'lifelike' situation when doing a pull.


Rgds