Janbros' 2-stroke excel for ports, heads and pipes

Non les 2 liens ne fonctionnent plus.

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

sorry, hosting site dissapeared and fotgot to change links here. new ones are in first post

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

due to a new post from Frits : [Vous devez être inscrit et connecté pour voir ce lien]
new donload in first post

I made a small correction to the calculation of the target Bd and transfer STA to get the correct target-value spot-on again with the new BMEP of the RSA

Nombre de messages : 5 Localisation : Essonne Date d'inscription : 17/01/2010

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Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

another small error reported, which caused the exh port width to be a little too low.
corrected link in first post

Nombre de messages : 1 Localisation : Finland Date d'inscription : 04/01/2023

Hello, the second download link is not working? could you fix it.
Thanks
Regards Eerik

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

should be fixed now

JanBros a écrit:: should be fixed now

can i use this for my single exhaust port 50-80 cc motors? i am mainly interested in designing an expansion chamber and how will it compare to blairs, torqsoft and the simple fos one stage pipe?
cheers

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

yes, read the manual

JanBros a écrit:: yes, read the manual

im reading the manual and straight away i cannot enter any data. only in the blank sheet but it doesnt go into another sheet. i get an error saying its protected. i have enabled editing.

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

you will have to be more specific than that, I just downloaded and tested it, and everything works.

JanBros a écrit:: you will have to be more specific than that, I just downloaded and tested it, and everything works.

Jan, I do not intend to pass judgment on where the problem lies. But this reminds me of a similar situation I once experienced.
A user of my software reported a malfunction that I could not reproduce until I tried it on someone else's computer whose settings were different from the settings on the computer on which I had developed and tested the software.

JanBros a écrit:: you will have to be more specific than that, I just downloaded and tested it, and everything works.

jan bros can you tell me exactly in idiot proof steps how to enter data so it appears on all sheets please? i know youve gone to a lot of trouble inserting all the macros and formula etc so one tiny little step would be much appreciated.

lets say i wanted to enter my cc 50cc. can you tell me where to enter it please. exactly whjich sheet and what should happen to it? thanks

Edit, and now for some strange reason i can input my data into the green squares. ive done nothing at all ive just left it open on my pc for 2 days. maybe it just needed time to cool down or something.....

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

did you save it on a "trusted location" ? if not, google "excel trusted location"
what excel version are you using ?

otherwise, try this, it's a stand alone of the FOS-pioe page
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and for those intersted, a stand alone of the HEAD-page :
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i am struggling. if my port width is 25mm i enter half of that? but then on the diagram of flow it looks too small/ also i cannot enter cylinder height deck height gasket thickness to give me correct readings on the exhaust new page. it comes out wrong ie deck height 0.3mm instead of 0.7. a.nd base gasket 2mm. but its 1mm
i have put the compression height in as you want it. not from centre of pin but top of hole to top of piston.

i am entering numbers into the new exhaust. should i be entering it on the old page?

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

aljaxon a écrit:: i am struggling. if my port width is 25mm i enter half of that? but then on the diagram of flow it looks too small/ also i cannot enter cylinder height deck height gasket thickness to give me correct readings on the exhaust new page. it comes out wrong ie deck height 0.3mm instead of 0.7. a.nd base gasket 2mm. but its 1mm
i have put the compression height in as you want it. not from centre of pin but top of hole to top of piston.

i am entering numbers into the new exhaust. should i be entering it on the old page?

you take a portmap and you enter the width of the port you measure as is. ONLY for the assymetrical ports, you enter the values from the "centerline" (of your own choice, it does not have to be the center) through the port to the in or outside of the port.

a lot of times I have doubted the whole cylinder height/spacer/.... thing, so I re-checked it and it appears to be correct. and yet I still doubt it. maybe you have found something that isn't correct. I haven't used it much, other than for experimenting when I created it. you can also keep it simple and enter the same .
off course this all only works if you enter your data "as your engine is before tuning" on the "old pages" , and than make the changes on the "new" pages.

i will have another look this evening.
on exhaust new page where do the values come from that fill the top left boxes? engine data?
they differ compared to my input

if i enter a totally wrong cylinder height on data page i can get deck height correct.
my port datas are wrong. i casn alter old they are green but new is yellow. and the port map picture for new the exhaust at height 0 is already at 5mm above deck height.
i might try input data for old instead of new.

old seems to be behaving

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

aljaxon a écrit:: jan bros can you tell me exactly in idiot proof steps how to enter data so it appears on all sheets please? i know youve gone to a lot of trouble inserting all the macros and formula etc so one tiny little step would be much appreciated.

lets say i wanted to enter my cc 50cc. can you tell me where to enter it please. exactly whjich sheet and what should happen to it? thanks

first you fill in all the green cell's on the data page.
than you make a portmap of your cylinder, and fill all the nescecary green cell's on the old pages (only the appropriate for your engine, if you for example don't have aux exh ports, leave everything blank for them). after this, you do not change anything on everything "old".
than you create your new "tuning" on the new pages. or you start from scratch, or you copy all data from old to new (see the manual how, as there is a difference between dark and light green cell's) and change the numbers .

are you sure you haven't changed yellow cell's (by accident) ? maybe download it again so you know everything is ok.

no it wouldnt let me change the yellow cells.
i will start again. im gonna do another portmap using graph paper so as to determine the port widths easier om every mm line.
thanks for your help so far.

ok ive managed to fill in the old data and port map and i can see my exhaust port need some work. the safe roof profile is wrong and blowdown is wrong.[Vous devez être inscrit et connecté pour voir cette image]

however i have to bring the exhaust up to 200 degrees to get enough blowdown.

i rode this motor on monday and it screamed to over 10000rpm
and really started pulling from around 7000rpm. just when it should be running out of breath.
the pipe has a tuned length for 11000rpm iirc and i wonder if that is helping it breathe.

the first motor identical to this except 176 124 is also a screamer and revs to 12000 on the road with peak power at 9250 ish yet the blowdown suggests it runs out of breath at 3800.
so what is happening. have i got lots of power to unleash if i adjust my exhaust port?

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

you have left the BMEP at the same level as the Aprilia RSA125 and are aiming for 26HP. obvious it's running out of breath, your goal is way too high.

hahaha. i didnt spot that

ok on old exhaust i set bmep to 8 which gives 13bhp.
the first project motor (176 124) was dyno'd at 10.8 bhp at around 9250 rpm so i think this should be good for 2 more hp with more aggressive porting
so can i deduce that my exhaust port is ok but my transfers need more area?

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Nombre de messages : 6129 Localisation : Limoges Date d'inscription : 19/02/2016

N’y voyez pas d’offense, je suis d’humeur blagueuse aujourd’hui…
Est-ce qu’il y a le même en rayon pour les 4tps ?
Une colonne jaune, une colonne verte..
On remplit consciencieusement le jaune: nombre de cylindres, de soupapes, alésage x course…
Puis le vert.
On rentre:
La puissance souhaitée.
Le régime
Le taux de compression
La taille des soupapes
Et il nous dessine les arbres à cames avec la levée, le diamètre des conduits et la raideur des ressorts !
….et si on obtient trois centimètres à la levée des soupapes, c’est qu’on a été un peu trop optimiste.

Nombre de messages : 351 Localisation : Belgique Date d'inscription : 05/12/2011

aljaxon a écrit:: so can i deduce that my exhaust port is ok but my transfers need more area?

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yes, much more !

see last post

» [2 Stroke] How plug up a 2-stroke wristpin?
» [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 4)
» [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 2) (Locked)
» Help! Please two stroke experts !!
» Two stroke infos