ESE's works engine tuner

[SS90]

The first one from the same series of runs, (different exhaust), same carb, same head, but had a very high primary compression

All early runs I have saved are from screen shots, because at the time
of all this work, we had a printer compatibilty problem, and I had to save screen shots of everything, everything from the end of summer 08 can be printed.

The second run, (believe it or not), is exactly the same cylinder as the first run we have been comparing to bucketracers cylinder (20.1PS), and I mean EXACTLY, and we fitted the same exhaust as the first graph..... I assure you, the cylinder is the same 100%...... only the primary compression is more suitable to the set up.

The "hole" at 5,500 rpm, with some effort can be tuned out, its not easy, but it can be done (Baffle angle).... this cylinder and exhaust set up, if optimised, will see 23PS with 24 mm carb, and, if you have the energy (and a 34mm carb, or bigger) I have seen 27PS....... it is worth noting, 23PS is where the clutches start needing "a little work"

[F5 Dave]

. . .
The "hole" at 5,500 rpm, with some effort can be tuned out, its not easy, but it can be done (Baffle angle).... . . .

Do you think? Odd. Typically if the baffle angle is too steep the hole is considerably closer to peak power & the peak power is pretty peaky. Dual stage baffles are supposed to provide an extended over but are harder to get right than single cone. I would have thought that dip would have been an inlet compromise. A symptom of loading up perhaps. What was the inlet method? Over enthusiasm on the throttle on the dyno & a rich needle?

[SS90]

Do you think? Odd. Typically if the baffle angle is too steep the hole is considerably closer to peak power & the peak power is pretty peaky. Dual stage baffles are supposed to provide an extended over but are harder to get right than single cone. I would have thought that dip would have been an inlet compromise. A symptom of loading up perhaps. What was the inlet method? Over enthusiasm on the throttle on the dyno & a rich needle?

The dip at 5,500 is a really well known thing here, and is due to the exhaust... (Shallow long baffle angle) many people in the scooter scene have battled that for years (before my time), and indeed to you can tune it out with some carb set up, but it is never perfect (although it shows up much more on the dyno than on the road)

If you scroll back to about February or march, I posted a picture of the baffle angle of an exhaust.... It's the same design as the power graph.

the problem is more pronounced depending on which reeds you use in my experience... And the best ones for these types of exhausts, weirdly enough come from Polini, but they don't make them anymore! I will post a picture in the morning.

I used NSR250 reed blocks (which are pretty damned generic anyway), and one day on eBay I saw this weird reed block, from the early nineties, it cost €10 incl. Shipping, so I brought it, it took me ages to get round to testing it, but it cleaned the curves up massively...... The problem seems to be the with the high "scavenging suction" this exhaust design provides, the top reeds just stay open too much, causing a flooding of the inlet (boost bottle anyone?) when it "comes on the pipe"

When you see the reed valve you will see why it is effective in this area.

I am sure you are aware Dave, computer program designed pipes only get you so far.... Clip joints and A dyno.... That's how you learn, and the truth is every person I know who spends the time with clip joints comes away with a more powerful expansion chamber than the one they started with designed on a computer program .

[TZ350]

I am sure you are aware Dave, computer program designed pipes only get you so far.... Clip joints and A dyno.... That's how you learn, and the truth is every person I know who spends the time with clip joints comes away with a more powerful expansion chamber than the one they started with designed on a computer program .

The computer programe was usefull for getting us started on the right track, and now we are planning on a bit of chamber development of our own after Taupo, the plan is to make several sets of straight pipes with slip joint in the middle and try them on a dyno.

But for now we have to concentrate on getting the best out of what we already have.

I am very interested in these two curves and how the power spread was extended by retarding the ignition.



Fixed ignition blue, retarded green, usefull power spread looks like it could be from 8,500 to 11,500, for 3,000 rpm.

The boys have fitted a programmable ignition to Ned Kellys bike and are figuring out how to set it up and programe in a curve, dyno time is expensive but it will be interesting to see what can be done.....



The Ignitech ignition can also control water injection, green line, who knows if we can make that work but if it does and we can broaden the useable power by another 500 rpm then we would have a 3,500 rpm wide power spread and that has to be good.

But wait, there is more, and if we can make any of those ideas from Richban, Yow Ling, or Bucket for changing the plenums internal inlet tracts diameter work, then we could have a power spread over 4,000 rpm wide and that would be seriously good.



Red line 24mm carb, Blue line 34mm inlet tract. If the inlet tract inside the plenum could be varied from say 22 to 34 then the power spread would be a lot wider, maybe by as much as a 1,000 rpm.



Although making more power is nice, going for a wider power spread, like this graph would be better........

So at the moment we don't need much more power, we only need to concentrate on extending the power spread as wide as possible as we see that as the way to compete with the FXR's at Mt Welly, that and good handling bikes ........

[SS90]

Haha, yea, I relate to all that... Never tried water injection myself, thought about it many times though.

Honestly, have a look at your baffle angle and stinger length, if you could get the boys to make a up a clip section just for baffle angles and stinger lengths, you will be pleasantly surprised.

Do you remember the home built dyno, that used recorded sound?

The guys that invented it are not too far from me, they have a roller set up, it works really well, and accurate too... Would be a good project for Bucketracer.

I am of the opinion many shops in NZ charge too much for Dyno time.

[F5 Dave]

From what I've seen it is hard to make money out of a dyno in NZ.

I've made rudimentary joints for testing cones with clamps & thick foil tape. It lasts only a short time & you have to be prepared to check it after the run to confirm it was a valid one & clearly you need to have muffler totally self supporting.

[SS90]

From what I've seen it is hard to make money out of a dyno in NZ.

I've made rudimentary joints for testing cones with clamps & thick foil tape. It lasts only a short time & you have to be prepared to check it after the run to confirm it was a valid one & clearly you need to have muffler totally self supporting.

It's sort of true in Europe too (making Money from a dyno), there are some very specialized manufactures over here, that make cutting edge dynes for top companies, and they replace them every year, so you can lease last years hitech best for €150 per month... If you can't pull that in a month you should shut up shop I say.....

The best clip system I have seen to date was Graham Harris's Honda RS125 set up, of course it very bulky, and like you say, sealing it is the pain in the arse.

[Spearfish]

It's sort of true in Europe too (making Money from a dyno), there are some very specialized manufactures over here, that make cutting edge dynes for top companies, and they replace them every year, so you can lease last years hitech best for €150 per month... If you can't pull that in a month you should shut up shop I say.....

The best clip system I have seen to date was Graham Harris's Honda RS125 set up, of course it very bulky, and like you say, sealing it is the pain in the arse.

Is it possible to make a half decent dyno at home?

I knew someone who was building his own with an old commercial exercise bike connected by chain to an old set of electricians cable rollers. From memory the bike computer can load up the effort needed with some measurement of energy expended with revs etc?
He was interested if tinkering made improvements from his own datum rather than knowing accurately the hp.
It was going to be used to tune a kt100 cart engine his son was racing but I think it was a short lived interest and never finished.

[bucketracer]

.

I came across these photos of where it all began for Team ESE. NedKelly's barn fresh bike and a few photos of Ned and Tim punting the old GP's around Mt Welly.........

[SS90]

Is it possible to make a half decent dyno at home?

I knew someone who was building his own with an old commercial exercise bike connected by chain to an old set of electricians cable rollers. From memory the bike computer can load up the effort needed with some measurement of energy expended with revs etc?
He was interested if tinkering made improvements from his own datum rather than knowing accurately the hp.
It was going to be used to tune a kt100 cart engine his son was racing but I think it was a short lived interest and never finished.

Very possible, the hard stuff is the data box to calculate the correction factor. (atmospheric conditions)

There are plenty of home built dynos that have no correction factor, and you can buy pre made windows based programs very cheaply all over the place.

If you wanted one for a commercial venture, data boxes are critical (even then, top end stuff is about €5,000) but for "home", a basic programe, a pick up to count the roller speed, and you are away.

[koba]

Very possible, the hard stuff is the data box to calculate the correction factor. (atmospheric conditions)

There are plenty of home built dynos that have no correction factor, and you can buy pre made windows based programs very cheaply all over the place.

If you wanted one for a commercial venture, data boxes are critical (even then, top end stuff is about €5,000) but for "home", a basic programe, a pick up to count the roller speed, and you are away.

I have a few ideas on all this but its not going to be high on the project list for a great number of years yet!

[Leed]

...I have observed a fog of fuel and air outside a carburetor opening at certain rpm on the dyno...

probably just water vapour in the air condensing at the bellmouth in the same way as can be seen on Aircraft carrier jets throttling up - rather than carb coughing up any fuel mixture

I cant find anything decent (photo/video) of exactly what I mean but have a look at 3minutes 30seconds...
http://www.youtube.com/watch?v=QprQcfr45fk
observe how the intake flashes briefly white when the water condenses - better seen stationary or at takeoff
the same thing can sometimes happens on a plane (seen when landing) etc the air on top of the wing has to speed up to match the air below... pressure drops, water condenses

there is a velocity profile across the Bellmouth/Velocity stack, Mach 0 outside, maybe Mach 0.23 in the throat
at some point the air accelerates enough that the vapour pressure is sufficiently low for the water to condense

http://www.richard-seaman.com/Aircra...por8oClock.jpg

[F5 Dave]

Interesting, but why would this happen at some revs yet not occur, typically, when the engine is running at it's most efficient range?

[koba]

probably just water vapour in the air condensing at the bellmouth in the same way as can be seen on Aircraft carrier jets throttling up - rather than carb coughing up any fuel mixture

I cant find anything decent (photo/video) of exactly what I mean but have a look at 3minutes 30seconds...
http://www.youtube.com/watch?v=QprQcfr45fk
observe how the intake flashes briefly white when the water condenses - better seen stationary or at takeoff
the same thing can sometimes happens on a plane (seen when landing) etc the air on top of the wing has to speed up to match the air below... pressure drops, water condenses

there is a velocity profile across the Bellmouth/Velocity stack, Mach 0 outside, maybe Mach 0.23 in the throat
at some point the air accelerates enough that the vapour pressure is sufficiently low for the water to condense

http://www.richard-seaman.com/Aircra...por8oClock.jpg

What the hell?

I think fuel standoff outside a carb is a well established phenomenon.

Even just google it.

You see it accounted for in the design of airfilters and the like.

[speedpro]

I can see his point. Pressure drops in certain circumstances can definitely produce visible condensation. You would see it on 4 strokes as well if that was the cause of what we've observed. I think someone should try holding a lit gas torch up to the carb intake. That should answer the question.

I'd like to video the results, just out of scientific curiosity of course