ESE's works engine tuner

[Frits Overmars]

The other part that was and still is very confusing is the 2 pipes. They are cnc made from bar stock with very similar volumes, the std performance pipe has stinger of 4.5mm the slow pipe has stinger of 4.6mm , the slow pipe is 1.6 mm longer, but is 1600 to 1700 rpm slow. Only could do 38100 rpm, compared to 39700 of the std pipe. The header temp on the slow pipe is around 230 to 235 C, unsure of the header temp of the 1st run.

Neil, if I'm not mistaken you're playing with the Profi F2A engine that happened to cross my desk when Profi started producing our MB40 F3D engine.
I dug up some old files: 190° exhaust timing, 140° transfer timing and 0,14 cc combustion volume, does that sound about right?
I found a huge mismatch between blowdown angle.area (good for 26500 rpm) and transfer angle.area (good for 44000 rpm) but as Profi was happy with its performance, he decided not to change it, so all I did was calculate some pipes. If I remember correctly pipe #1 would be delivered with the engine while pipe #2 was experimental.
All pipe lengths are from the piston edge; all diameters are internal. Notice the narrow header and the 4,2 mm stinger diameter on #2?

[Lightbulb]

Thanks Frits, What design do you suggest I make ?
What wall section would you recommend ?
Some people used to use pipes with the smaller 4.2mm stinger, but they found that at the end of the flight it would be burning down,
ie going slower. Quite often resulting in a no flight as it would stop on lap 7 or 8 of 9. Some how, they are getting it hotter or something
and making it run faster in the model and in the air under load than the engine ever could on a test bench situation and some are getting
3% more in the top end, so are running to 40700 rpm when on the bench only does about 39500 or so.
Neil

[Flettner]

Thanks Frits, What design do you suggest I make ?
What wall section would you recommend ?
Some people used to use pipes with the smaller 4.2mm stinger, but they found that at the end of the flight it would be burning down,
ie going slower. Quite often resulting in a no flight as it would stop on lap 7 or 8 of 9. Some how, they are getting it hotter or something
and making it run faster in the model and in the air under load than the engine ever could on a test bench situation and some are getting
3% more in the top end, so are running to 40700 rpm when on the bench only does about 39500 or so.
Neil

Same as with a gyro engine, tie the autogyro to a fence and you might see 6200 then in flight it will pull to say 6500 or so. The difference is having to pull the air through the blade (static) veres air being introduced to the prop in flight, I guess angle of attach of the blade. I've just woken up so I might have the wrong end of what you are talking about.

[Frits Overmars]

Thanks Frits, What design do you suggest I make ? What wall section would you recommend ?
Some people used to use pipes with the smaller 4.2mm stinger, but they found that at the end of the flight it would be burning down,
ie going slower. Quite often resulting in a no flight as it would stop on lap 7 or 8 of 9. Some how, they are getting it hotter or something
and making it run faster in the model and in the air under load than the engine ever could on a test bench situation and some are getting
3% more in the top end, so are running to 40700 rpm when on the bench only does about 39500 or so.

As these straight pipes are fairly easy to build, I would try both designs, using 0,3 to 0,4 mm mild steel sheet. And you might want to try lower compression ratios than the Profi F2A's standard 19:1.

Same as with a gyro engine, tie the autogyro to a fence and you might see 6200 then in flight it will pull to say 6500 or so. The difference is having to pull the air through the blade (static) veres air being introduced to the prop in flight, I guess angle of attach of the blade. I've just woken up so I might have the wrong end of what you are talking about.

Must have been a fruitful nap Neil; I was going to give the same answer. And you can put the effect to good use: impede the airflow to the prop, so it gets to run in its self-created vacuum, and the revs will go up.
When I first demonstrated the technique, it must have looked like magic to the bystanders. There was an engine running on the test bench (nothing to do with a dyno, just a heavy lump of cast iron) and it couldn't manage to pass the torque dip and get on the pipe. I just put a pan lid right in front of the prop, almost against the spinner, and the revs shot up. It's like putting your hand on a vacuum cleaner's hose and hearing the revs rise.

[TZ350]

Page 1370 ....

http://www.con-rod.com.tw/motorcycle-connecting-rod.htm
http://www.google.co.nz/url?sa=t&rct...MVppLeMVAqjHUA

Found this cattledog today it a euro one so useful for weird euro stuff
http://http://www.pbr.it/index.php?o...mid=99&lang=en

It is actually made for a RG500 but........
http://www.maranello-engineering.com...3mm-p-244.html
Nice site though. Nice Rg500 cylinders as well.

http://www.mxcomposites.com/con_rod.php
http://www.connectingrod.com.tw/ktm.htm
http://www.pro-x.com/downloads/Technical.pdf
http://www.kevinbreedonracing.co.uk/...ts_conrods.asp
http://www.connectingrod.com.tw/honda.htm
http://www.samarin.nl/webshop/index....ewCat&catId=32
http://www.tkrj.co.jp/
http://findebookee.com/c/connecting-rod the one is capt
http://dl.dropbox.com/u/399336/Pictu...ted/HotRod.pdf
http://www.kingrod.com.tw/products.p...t&pc_parent=22
http://www.crankshaftparts.com/index...7_93&limit=100
http://shop.atlanticmotoplex.ca/prod...catalogId=2016
http://jjmachineryonline.com/snowmob...onnecting-rods
http://www.scooter-center.com/scoweb...y2=CAT&lang=en
http://www.bansheedepot.com/products.asp?cat=17
http://http://www.samarin.net/?productos
http://www.pvlsverige.se/vrm/index/index22.html

If you are looking for 2T tuning technical information I have found this thread is best read backwards, ie start at the last page and read back towards the beginning.

Transfer Port theory

There are also over 7000 images on this thread, use "Thread Tools" to view them and then click through to the original post about them.

Use Google so to search this site use an ordinary search phrase and after it add


site:www.kiwibiker.co.nz


for example


Frits priceless site:www.kiwibiker.co.nz
or
Frits pisa site:www.kiwibiker.co.nz


the same will work for other sites with the appropriate site address


Mick

A lot of the decade pages have collections of quotes and links to other interesting things.


Page 1250 Links List
Page 1240 2T development Software, Port Theory, Interesting Sites
Page 1230 Compression Ratio, Ex duct shape and length, Fancy spark plugs.
Page 1220 Reed Valve Petals, Oxygen Sensors, Exhaust duct step at the pipe flange.
Page 1210 Ignition Trigger Woes, EngMod 2T and Blow-Down, Fuelling Curve.
Page 1200 Frits on power spread and the ratio of the maximum and minimum points in the power band.
Page 1190 No data, but a lot of talk about what the Ryger engine might look like.
Page 1180 Frits on 2T fuel consumption. M50 cylinder portmap and EngMod2T analysis.
Page 1170 Engine/Gearbox oils and bearings. Transfer duct shape and optimal Ex port timing.
Page 1160 Frits - Engines need large crankcase volumes, Power vis Handling.
Page 1150 Serious talk about crankcase volume.
Page 1140 Measuring the transfer duct length, Ignitec, Expansion chamber design, Trombone pipe.
Page 1130 Team GPR Edgecumbe Videos …. Cooling 2T’s …. 3xEx vis T port,
Page 1120 Crank Balancing, Ceramic Coating, Plugs, Piston Edge chamfers, RS125 pipe dimensions.
Page 1110 TeeZees progress on the EFI thing with the Beast.
Page 1100 No Data but some talk about pickups and EngMod 2T transducer position in the pipe.
Page 1090 Links about the Detonation Sensor and Temperature Data Logger.
Page 1080 No Data, the plenum is protested, Frits on Blowdown and Transfer window height.
Page 1070 Exhaust Duct shape, Kawasaki and BRC EFI dyno videos.
Page 1060 No Data but talk about Port shape and Flow in a duct on this page.
Page 1050 EngMod2T setup talk about pipes, transfer ports and the TubMax graph.
Page 1040 Basics of pipe design and how to influence where the point of maximum depression occurs.
Page 1030 Racing at Greymouth, its well worth a look to see Team GPR in action.
Page 1020 Pipe dimensions, Seattle Smittys hydroplanes. Husaburgs piston link.
Page 1010 Suspension Tuning.


Page 1000 has a lot of useful information and links. http://www.kiwibiker.co.nz/forums/sh...post1130773139

Page 990 Blowdown STA, Ex porting plated cylinders, port layout and port angles.
Page 980 No links list but there is talk about spark energy and EGT
Page 970 Fuel - Oil and EGT talk
Page 960 Wob - Fuel and Oil Talk and Crank inertia.
Page 950 Its all about exhaust blow down …..
Page 940 Fixers 50cc adventures – ports & heads – Wob talks about Bad Gas.
Page 930 Frits 50cc pipe – Husburgs large links list, parts books, steering head brgs
Page 920 Big links list, allsorts. Tokoroa GP videos.
Page 910 No links list but the page is about fitting a 12V generator stator.
Page 900 Frits thoughts on O2 sensors – EFI Fueling theory – Wob on EGT
Page 890 DIY Foundry tips – EFI data – Detonation Management (tec paper) – more EFI
Page 880 Big list of Flettners Foundry posts and pictures.
Page 870 YZ & Bighorn Dyno results – Dyno Vids and EFI talk
Page 860 Air cooling and ducting and Carb air inlets, next page Greymouth Race
Page 850 1st run of the EFI Beast
Page 840 Husaburgs big links list on Power Jets – High temp epoxy and Ex port dam.
Page 830 Plugging piston pins – Cyl Heads (no radius) and Plug to Piston distance.
Page 820 Det sensor & Ignitec setup – Exhaust port dam – Boost Bottle – Insulating Paint
Page 810 Links – about Razing the Exhaust port floor
Page 800 Link to dyno graphs for the YZ & BigHorn EFI Bikes & a lot of EFI stuff
Page 790 Car & bike museum pics _ Wobs pipe.
Page 780 Setting up an IgniTec DC-CDI-Race-2 ignition – Big list of links.
Page 770 Wobs views on triple ex ports – first run of the EFI YZ250
Page 760 Port Angles – lots of Pipe design info – Fast model aero engine.
Page 750 Case Com – Basic 2T tuning – BigHorn EFI
Page 740 Case Vol – Deto – Inlet Length – Over rev deto.
Page 730 Pipes – Deto – Lambda – Temp probes – CrankCase CR – Variable headers.
Page 720 Inlet tract length – GP125 service manual – Picture of how to read a plug + Wobs comments
Page 710 Fuel and Power Jets - EGT and CHT - Crank build
Page 700 Talk about wide and low transfers – Case volume and dyno graph – det and Lambda sensors.
Page 690 Pipe talk and ideas about making mufflers.
Page 680 Talk about the Trombone pipe and more of Frits and Wobs views on pipes.
Page 670 Pipes – blowdown STA numbers – Trombone pipe.
Page 660 Lots of links on pipes – Ariel Arrow – and CVT
Page 650 Links – Frits and Wobs views on pipes – CVT transmissions – 30 vis 24 carb dyno graph
Page 640 Links to Wobs views on pipes – crank balance factor – connecting a laptop to the Ignitec
Page 630 More of Wobs views on pipes – Frame & wheel weights – correct O ring grove sizes
Page 620 Links to Cooling Water Flow – Case Comp and Pipes – Setting up 2T carburation.
Page 610 Simulation packages – combustion efficiency – transfer ducts – chamfered exhaust top edge.
Page 600 Books that can be down loaded and Frits talks about why 190 Ex duration is so good.
Page 580 No links but page is about mounting carbs and the 24mm pumper carb & 28hp dyno graph.
Page 570 No links but the page talks about carburation – emulsion tubes and pilot jets.
Page 560 No links, the page is mostly about 96 vis Av gas with dyno test.
Page 550 No links list but the page is mostly about TZ400 build and cranks and rods.
Page 540 No links, the page is mostly about Wobs success with the 400 project.
Page 530 Ignition – setting up det sensors without a dyno – wings inside reed valves – poly quad head
Page 520 Mostly about what some wheels weigh, ATAC valves and crank stuffers.
Page 510 Bucketracers general Links List
Page 500 Bucketracers links list of how to make a mid 20’s hp Suzuki GP125

Page 490 The Trombone, Ex port resonance and Transfer port stagger.
Page 480 A vid of the Trombone, transfer timing and hot gases entering the transfers because of insufficient blow-down for the rpm.
Page 470 Blow-down STA ... Specific Time Area.
Page 460 No list but the page talks about Boost Bottles.
Page 450 Links to the basic info for building a 30+ hp Bucket.
Page 440 No list, page talks about power and air correction jets.
Page 430 Carb inlet lengths and crankcase volumes.
Page 420 Transfer ports and the importance of the up swept angles, the Leaning Tower of Pisa principle explained.
Page 410 Rolling road dynos, main and power jet ratio.
Page 400 Links to the basic info for building a 30hp Suzuki GP125 Bucket engine.
Page 390 Links to Frits collection of Aprilia stuff.
Page 380 Transfer duct shape and STA's.
Page 370 No list but the page talks about Jan Thiel and racing 50's.
Page 360 Frits chamber calculations formula.
Page 350 PJ switching, Wob and crank shaft balance.
Page 340 Muriatic Acid, main brg float, Husburgs con rod dimensions.
Page 330 No list, page talks about expansion chambers, race gas.
Page 320 High temp silicon, Yama Bond, crankcase sealing, air solenoids Vid clips of Mamola.
Page 310 Copper for cooling, sprockets for cooling, steering head brgs.
Page 300 How to determine STA numbers.
Page 290 B/E dimensions, delivery ratio, Honda Ex Step, stinger nozzel
Page 280 Aprilia RSA port layout explained, pumper carb, links to gluing up the GP cases.
Page 270 Link list on how to make a decent high 20's hp Suzuki GP125 Bucket engine.
Page 260 Over rev cough and what it means, Mallory metal for crank balancing.
Page 250 27hp from a 1978 Suzuki GP125
Page 240 Aprilia RSA cylinder stuff.
Page 230 Porting Calculator and a lot of other useful tech links.
Page 220 RG50 part numbers, 2-stroke carb atomisers explained
Page 210 Page is mostly about the results from the TRRS
Page 200 Simple 18 hp Suzuki GP Bucket engine using a RG250 pipe.


Etc ...

On Page 500, Bucket has links to how Team ESE built their 26, 28 and 31 hp engines:- http://www.kiwibiker.co.nz/forums/sh...-tuner/page500

[chrisc]

Question for Wobbly/Frits/anyone else with lots of inlet testing experience below

From what I've read on the ESE thread I believe the straightest and shortest path from reed to carb (or disk to carb) is best for a highly tuned 2 stroke. I'm unsure if this is generally what all race 2 stroke tuners should aim for or if it's something that depends on the engine performance level and tracks raced at.

The Honda RS125 manifold changes went:
pre 95 NF4 (far right in photo) - Medium length rubber mount with a horizontal angle, small square 'stuffers'
95 to 97 NX4 (far left in photo) - Short straight rubber mount, longer larger stuffers
98 onwards NX4 (middle in photo) - Longer straight rubber mount, same longer larger stuffer and 95-97 NX4

Am I right in saying that the 98 onwards longer manifold was to increase lower RPM power? Would the short straight manifold be better for a highly tuned 125 for use on tracks with larger straights?

[TZ350]

.............

[wobbly]

The shorter old model straight rubber is best.
Here is a very old dyno test I did on a TM125MX motor we used to race in 125 National class karts, this was used with a VeeForce 2 and a bored SPJ powerjet carb..
Its a crap printout - used to be orange and red, but the short manifold looses no mid power, but is near 2 Hp up around peak.
The short rubber is obsolete and all but impossible to find.

[TALLIS]

I'm sure Honda spent millions dollars updating and developing there engine before it was erelevant , it's not like they have a dyno, or experience in 125's or people that know what there doing, what would they know.

[Frits Overmars]

From what I've read on the ESE thread I believe the straightest and shortest path from reed to carb (or disk to carb) is best for a highly tuned 2 stroke. I'm unsure if this is generally what all race 2 stroke tuners should aim for or if it's something that depends on the engine performance level and tracks raced at.
The Honda RS125 manifold changes went:
pre 95 NF4 (far right in photo) - Medium length rubber mount with a horizontal angle, small square 'stuffers'
95 to 97 NX4 (far left in photo) - Short straight rubber mount, longer larger stuffers
98 onwards NX4 (middle in photo) - Longer straight rubber mount, same longer larger stuffer and 95-97 NX4

The NF4 was really a motocross engine; the slant manifold served to move the carburettor out of the way of the central rear shock absorber. The effect was twofold:
The flow was reluctant to follow the bend; it concentrated on the outside, so the reeds on that side were overloaded and perished, while the reeds on the opposite side could have been much thinner because they hardly saw any flow at all.
The same was true for the crankshaft main bearings: the left-side bearing hardly received any premix lubrication. And boy, were those Honda main bearings expensive.
The short straight manifold worked a lot better, as Wobbly wrote.
So why substitute it with the long straight manifold? My guess is: to better isolate the carburettor from engine vibrations.

[Frits Overmars]

I'm sure Honda spent millions dollars updating and developing there engine before it was erelevant , it's not like they have a dyno, or experience in 125's or people that know what there doing, what would they know.

I don't really see the relevance of your reaction, but since you're here, tell us about your years at Honda R & D.
I'm getting the impression that each time Wobbly posts anything, it gets scorned. I've done my best to stay out of the dispute but the next time Wobbly says farewell, so will I. I'm sorry for all the good people here but I'll leave it to them to deal with the rioters that are destroying the atmosphere of the thread; I don't need this aggro.

[dtenney]

I don't really see the relevance of your reaction, but since you're here, tell us about your years at Honda R & D.
I'm getting the impression that each time Wobbly posts anything, it gets scorned. I've done my best to stay out of the dispute but the next time Wobbly says farewell, so will I. I'm sorry for all the good people here but I'll leave it to them to deal with the rioters that are destroying the atmosphere of the thread; I don't need this aggro.

Excellent reply Frits! You and Wobs have been very generous with your posts....thanks for that. I can assure you there are a lot of folks on this thread that really value the information being shared. For 2 stroke geeks this IS the place to hang out!

[teriks]

Excellent reply Frits! You and Wobs have been very generous with your posts....thanks for that. I can assure you there are a lot of folks on this thread that really value the information being shared. For 2 stroke geeks this IS the place to hang out!

The best place I'm aware of for sure, much due to real knowledge being shared so generously in contrast to many other forums.
Unfortunately I dont have much to contribute with compared to people like TZ, Wob, Frits, Flettner, Ken, Lightbulb.. to name just a few.
Perhaps because I have learned enough about the seemingly simple two-stroke to know that I know just about nothing..

[Martin1981]

I'm sure Honda spent millions dollars updating and developing there engine before it was erelevant , it's not like they have a dyno, or experience in 125's or people that know what there doing, what would they know.

stop that bullshit because we don`t want Wobbly and Frits to leave. Some stupid braindead Idiots seem not to know which Guys they are talk to when getting into a fight with wobbly and Frits. To Idiots like that i can only say shut up and leave before Frits and Wobbly do. Having worked and developed 2 stroke racing engines for probably 50 years or so seriousely and then getting told by an idiot that one is telling rubbish and bye the way, as far as i know wobbly worked for honda, didn`t he?

[F5 Dave]

Yeah cmon guys. Most of the issue are 4 stroke riders posting late at night. If you want to get drunk and stick it round a bit, and I've been guilty of internet cajoling after a few bevies, - But please leave this thread alone. It is a unique and long running resource.