AccueilGalerieRechercherDernières imagesS'enregistrerConnexionNouveaux messages depuis dernière visite
Rechercher
 
 

Résultats par :
 
Rechercher Recherche avancée
Qui est en ligne ?
Il y a en tout 35 utilisateurs en ligne :: 7 Enregistrés, 0 Invisible et 28 Invités :: 2 Moteurs de recherche

CDVC, demeilliers, dga, Garelli250, MONET H2, philippe7, thierysp

Le record du nombre d'utilisateurs en ligne est de 588 le Jeu 26 Sep 2024 - 6:33
Derniers sujets
»  [oldies] BOURG en BRESSE 1972
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeAujourd'hui à 9:26 par philwood

» Honda V3 en préparation
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeAujourd'hui à 9:14 par Dan42

» [Interview] Guy Coulon
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeAujourd'hui à 8:25 par bartau

» Malheureusement ils sont partis... et ils n'avaient rien à voir avec la moto
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 21:16 par Joel Enndewell 2424

» Bourg en Bresse 1964
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 17:48 par DidierF

» [Technique] La petite histoire du Desmo
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 14:20 par Charly

» [Oldies] Questions (vitesse 1947-1976) (2)
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 12:46 par DidierF

» [Oldies] Casques Premier 1974
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 9:50 par philippe7

»  [WSBK] Infos 2025 .
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeHier à 8:54 par les marluches

» [Oldies] Quizz (30)
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMer 6 Nov 2024 - 16:57 par jeannin

» Der de der Barcelone....
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMer 6 Nov 2024 - 15:46 par Aragon

» [Oldies] 80cc de vitesse : Toute leur histoire !
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMer 6 Nov 2024 - 15:13 par Nonoche

» [Oldies] Des livres sur la course moto
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMer 6 Nov 2024 - 14:19 par dga

» [oldies] GP Autriche Salzburg 1974
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 20:38 par DidierF

» [Oldies] Barry Sheene, trajectoire d'une star
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 16:45 par philippe7

» [Oldies] Jack Findlay, pilote de légende
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 13:29 par jack177071

» [Technique] Réglage Keihin PWK28 sur 2t de trial
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 10:24 par Troli

» Intempéries Valencia.
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 8:55 par Aragon

» Bretagne Moto Classic 2024
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 5 Nov 2024 - 5:52 par diablo262

»  [MotoGP] GP 2024 de Malaisie à Sépang - Les 1 , 2 et 3 Nov 2024 .
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 4 Nov 2024 - 23:12 par Charly

» PROGRAMMES MANQUANTS - PGPM
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 4 Nov 2024 - 20:09 par sidthouv

» [Oldies] Les Koehler Escoffier
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 4 Nov 2024 - 19:01 par jeannin

» TT 1979:le dernier pour Mike Hailwood.
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 4 Nov 2024 - 12:51 par jack177071

» [Oldies] Questions (vitesse 1947-1976)
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 4 Nov 2024 - 12:46 par DidierF

» epoquauto 2024
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeDim 3 Nov 2024 - 20:40 par cateralp

» [Oldies] Side-Car: quelques images
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeDim 3 Nov 2024 - 20:01 par Fanchiom

» [Oldies] Aux origines...
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeDim 3 Nov 2024 - 18:35 par Apriliabarth

» Bourg en Bresse 1958
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeSam 2 Nov 2024 - 22:34 par DidierF

»  [MotoGP] Infos , nouveautés , potins , tests et plus pour la saison GP 2025 ...
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeSam 2 Nov 2024 - 15:31 par EDOUARD Jean

» [2Stroke] Les MZ & Mr Walter Kaaden
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeSam 2 Nov 2024 - 10:42 par jack177071

Mots-clés
artisanales bourg rouge fior moto 1973 ROAD zone side ducati charade suzuki motos coupe yamaha aprilia wanted 1976 inventaire bresse francaises 2013 oldies classic Mans RACING
Meilleurs posteurs
Marc
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
EDOUARD Jean
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
philwood
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
Pierre"PhilRead"
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
mickey
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
yves kerlo
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
bubu
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
Fügner
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
Dialmax
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
Dan42
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting16[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting13[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Voting15 
La réclame...
-25%
Le deal à ne pas rater :
PC Portable Gamer 16,1” HP Victus 16 – 16 Go /512 Go
749.99 € 999.99 €
Voir le deal

 

 [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)

Aller en bas 
+104
wos
koenich
LeonardoMRF2
Rookie j.
Zrt1200
motori49
F888
pagi
Eric_91
Panas
Charly
polcat88
Adco
Scalvo
tenney
andreas länström
EDOUARD Jean
flatart
Peljhan
RAW
thankspipe
op76
iizquierdo
Fredrikgu
fullgazlolo
Virgil Tripp
Vannik
ReinanRacing
carlovitch1
patouille
taliesin
Laci
Institute of TwoStrokes
tzrcarbonn
Freitas_rt
porttiming124
Döllinger
freret alain
ORC
pascaltz
GtG001
Iker
alextatic
marsheng
Ken Seeber
dutch
Jseb89
uniflow
crayou
Jenco
lvs
50cc
Howell
peter1962
Apriliabarth
41juergen
fd-racing
marlow
Paul Olesen
seattle smitty
bentou
Polux rsv
jona2t
LucF
CVS
alwoodman1
Maurice Specken
pierre95
laranjateam
Manuel Rainer
Forgi
Berglund
alcatelko
williamsmotowerx
lodgernz
jfn2
pfpraider
Mks-Racing
husaberg
cassandre
gab
Toop
Niels Abildgaard
motoholic71
tjbw
Phytus
Howard Gifford
yeahhim
MANETON
ktuningteam
fpayart
Al mach
Rose Noire
Bob van der Zijden
Senne s
Marc
Piquer
JanBros
ambike
Frits Overmars
Jan Thiel
Lef16
yesyes
Dan42
108 participants
Aller à la page : Précédent  1, 2, 3, 4, 5 ... 22 ... 40  Suivant
AuteurMessage
alcatelko




Nombre de messages : 32
Age : 41
Localisation : slovakia
Date d'inscription : 26/09/2011

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 13:22

less friction have pistons from powder aluminium :) left is Al-Si cast piston, right is forged from nano Al powder
[Vous devez être inscrit et connecté pour voir cette image]
Revenir en haut Aller en bas
http://www.50cm3.eu
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 13:25

quote="williamsmotowerx"]In my opinion cast pistons have less friction than the forged[/quote]

Forged pistons always have a tendency to deform at the 'bottom' which is really the top.
You get worse flow, and a lower compression ratio.
With a cast piston you don't have these problems.
As the 'bottom' can be reinforced by ribs.


Dernière édition par Jan Thiel le Mar 15 Mar 2016 - 13:51, édité 1 fois
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 13:32

I have lost a lot of postings because I thought this topic had been closed......
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 13:58

The Tansini later called Jamathi had about 9HP, aircooled
The Dutch TT winner of 1968 had about 12HP I think, watercooled
These are estimates, because at the time we did not have a dyno...


Dernière édition par Jan Thiel le Mar 15 Mar 2016 - 14:19, édité 1 fois
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 14:06

The RSA connecting rod was only lengthened to improve inlet flow Howard.
At Bultaco I once tested a 95mm connecting rod, instead of the usual 85mm.
With the 50cc engine.
The result was less power.
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 15 Mar 2016 - 14:18

The inlet disc diameter was 126 on the RSW and RSA.
A bigger diameter was tried, but proved to give no more power.
The biggest disadvantage of the RSA was the inclined carburator, causing a lot of trouble.
The carburator was made by Dell'Orto, I did not like it at all!
Japanese carburators usually don't give any problems when inclined.
The KEIHIN used on the 125 reedvalve Derbi engine 'made' by Bartol never gave any trouble.
It's only problem was very low HP, about 47,5
Revenir en haut Aller en bas
williamsmotowerx




Nombre de messages : 15
Localisation : usa
Date d'inscription : 24/12/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeJeu 17 Mar 2016 - 6:34

Jan Thiel a écrit:
The RSA connecting rod was only lengthened to improve inlet flow Howard.
At Bultaco I once tested a 95mm connecting rod, instead of the usual 85mm.
With the 50cc engine.
The result was less power.

I built a cr125 for motocross, going off memory 100mm stock rod, I currently have a 110mm rod in motor.

Bottom end power is lacking, I'm probably going to go back to 100mm rod and try that.

I thought main reasoning for 120mm rod was less friction. You're saying 120mm rod allowed a less obstructive intake port? That's reason for long rod?
Revenir en haut Aller en bas
Lef16




Nombre de messages : 12
Localisation : Hellas
Date d'inscription : 02/03/2014

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 29 Mar 2016 - 21:09

Could you tell us a little more on how tailpipe length affects power?
Cheers
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMer 30 Mar 2016 - 5:57

If you put a 'restrictor' just at the end of the pipe the length of the tailpipe will become a lot less critical.
You can find a design of such a restrictor in earlier posts on this site.
I think the first one to use this system was Helmut Fath.
Revenir en haut Aller en bas
Berglund




Nombre de messages : 3
Localisation : Sweden
Date d'inscription : 10/02/2015

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeJeu 31 Mar 2016 - 13:54

Jan Thiel a écrit:
If you put a 'restrictor' just at the end of the pipe the length of the tailpipe will become a lot less critical.
You can find a design of such a restrictor in earlier posts on this site.
I think the first one to use this system was Helmut Fath.

What information would you normally take into account during testing when determining a good restrictor size / diameter?

I strive to run with as large restrictor diameters as possible to increase the reliability of the engine. Most often, a small peak power loss as a result of increasing the restrictor diameter can be compensated with a slightly shorter overall tuned length of the pipe. The downside is that it usually costs some low end power.

Do you know if the RSA where ever driven with different restrictor sizes on the track than what was delivered with the standard exhaust?


// Karl-Magnus

Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeVen 1 Avr 2016 - 4:47

Om the 250 a diameter of 23,25 was used, on the 125 23.0
Once determined they were never changed.
And they were welded to the pipe
For the rest I fully agree with you!
Revenir en haut Aller en bas
Berglund




Nombre de messages : 3
Localisation : Sweden
Date d'inscription : 10/02/2015

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeVen 1 Avr 2016 - 9:28

Jan Thiel a écrit:
Om the 250 a diameter of 23,25 was used, on the 125 23.0
Once determined they were never changed.
And they were welded to the pipe
For the rest I fully agree with you!

Thanks for your reply Jan! Much appreciated!
(I will do my best to avoid asking already asked questions)

Where there any HP sacrificed for reliability's sake? (My guess would be Yes).
If so, would you dare to guess what could have been produced on the dyno in terms of HP if the reliability aspects was breached?

// Karl-Magnus
Revenir en haut Aller en bas
Jan Thiel




Nombre de messages : 517
Age : 84
Localisation : Bangkok
Date d'inscription : 12/10/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeVen 1 Avr 2016 - 10:54

Never on the dyno Karl-Magnus
We always started with a too rich carburation.
Then jetted down until maximum power was reached.
We could then go still weaker, losing power, without problems.
On-track was a different story.
Carburation had to be richer because of detonation problems at part-throttle. (auto-ignition)
And because of the air-box giving higher air pressure at speed.
On the dyno the air-box gave less power....
Revenir en haut Aller en bas
Berglund




Nombre de messages : 3
Localisation : Sweden
Date d'inscription : 10/02/2015

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeVen 1 Avr 2016 - 12:21

Jan Thiel a écrit:
Never on the dyno Karl-Magnus
We always started with a too rich carburation.
Then jetted down until maximum power was reached.
We could then go still weaker, losing power, without problems.
On-track was a different story.
Carburation had to be richer because of detonation problems at part-throttle. (auto-ignition)
And because of the air-box giving higher air pressure at speed.
On the dyno the air-box gave less power....

Many thanks Jan for taking your time answering these questions!
Have a nice weekend!

// Karl-Magnus
Revenir en haut Aller en bas
Forgi




Nombre de messages : 29
Age : 42
Localisation : Budapest
Date d'inscription : 19/09/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeSam 2 Avr 2016 - 22:18

Dear Jan!

Do you know how did the geometry of pistons used in the Aprilia look like? How much was its taper (under and above the ring, and how long), did it have ovality and if the answer is yes then how much was it?

Thanks in advance!
Revenir en haut Aller en bas
http://mibavit.com
Manuel Rainer




Nombre de messages : 98
Localisation : Italy
Date d'inscription : 30/10/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeDim 10 Avr 2016 - 17:57

hello

a question to all.
can someone give me a tip what can cause this problems with detonations and the crack in the center of the piston. let away the damage under the piston ring.

a few information the the engine.

94 ccm polini 52x44 CVT engine, rotary valve, 30 VHSH dellorto carburetor 95 octane unleaded fuel, driven on a smal kart track constant on 13000 rpm. exhaust temp max 350 °C about 45 mm away from the piston, NGK 10 iridium.

[Vous devez être inscrit et connecté pour voir cette image]

it can be the ignition or the carburetor setting what i think. ignition is a non digital one set to 28° btdc like said from the factory. i have testet many carburetor settings put i dont know.

thanks Manuel
Revenir en haut Aller en bas
laranjateam




Nombre de messages : 20
Localisation : Palmela Portugal
Date d'inscription : 04/03/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 0:31

A tip , this engine is sealed ?
Revenir en haut Aller en bas
alcatelko




Nombre de messages : 32
Age : 41
Localisation : slovakia
Date d'inscription : 26/09/2011

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 9:36

bad design of the cylinder head? squish, compression ratio due to octane nr.
Revenir en haut Aller en bas
http://www.50cm3.eu
Manuel Rainer




Nombre de messages : 98
Localisation : Italy
Date d'inscription : 30/10/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 20:47

hi

laranjateam
what do you mean with sealed? the cylinder to the crankcase is sealed with a gasket, head to cylinder with O ring. and the crankcase with silicone sealing.

alcatelko
the cylinder head design is nearly like the RSA. squish is 0,9 and the compression is 15:1 on 95 octane like i said.

i think the numbers should work, but i don't know.

thanks manuel

Revenir en haut Aller en bas
JanBros




Nombre de messages : 362
Localisation : Belgique
Date d'inscription : 05/12/2011

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 21:27

Manuel Rainer a écrit:
the compression is 15:1 on 95 octane like i said.

I'm no tuner, but that seems very high for only 95
Revenir en haut Aller en bas
Manuel Rainer




Nombre de messages : 98
Localisation : Italy
Date d'inscription : 30/10/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 21:41

JanBros a écrit:
Manuel Rainer a écrit:
the compression is 15:1 on 95 octane like i said.

I'm no tuner, but that seems very high for only 95

the RSA has 16:1 with 95 octane as a think
Revenir en haut Aller en bas
JanBros




Nombre de messages : 362
Localisation : Belgique
Date d'inscription : 05/12/2011

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeLun 11 Avr 2016 - 22:07

Manuel Rainer a écrit:

the RSA has 16:1 with 95 octane as a think

so with 95 octane you do not mean euro 95 Embarassed
Revenir en haut Aller en bas
alcatelko




Nombre de messages : 32
Age : 41
Localisation : slovakia
Date d'inscription : 26/09/2011

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 12 Avr 2016 - 7:31

I use 15:1 ratio at 50ccm engine and normaly I use RON 100 fuel...if is used RON 95 fuel main jet must be bigger (120 @ RON 100 fuel and 128 @ RON 95 fuel)
Revenir en haut Aller en bas
http://www.50cm3.eu
pierre95




Nombre de messages : 111
Localisation : val d'oise
Date d'inscription : 14/12/2010

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 12 Avr 2016 - 18:06

hi
i am not a tuner too but first for 50cc a squish at 0.9 it's big remember what Jan said 10% of the stroke or just a bit more , whatever the fuel you use try to use always the fuel which provide the higher octan ratio, also it seems you carb jetting was too lean.Maybe also not enough advance to you ignition timing.
Pierre
Revenir en haut Aller en bas
Manuel Rainer




Nombre de messages : 98
Localisation : Italy
Date d'inscription : 30/10/2012

[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitimeMar 12 Avr 2016 - 21:08

hi

JanBros
i use normal italian 95 octane unleaded super

alcatelko
thanks for the info. i drive a 175 main jet on this 94ccm. that's also my decision to use 100 octane.

pierre95
this engine has 44 stroke. 0,9 is on the safe side. but if i want to reduce the squish, i have to modify the head geometry, otherwise i have too much compression.
i have to check the ignition in the high revs. on 13000 rpm 14°-12° i think.

thanks manuel
Revenir en haut Aller en bas
Contenu sponsorisé





[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Empty
MessageSujet: Re: [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)   [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5) - Page 4 Icon_minitime

Revenir en haut Aller en bas
 
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)
Revenir en haut 
Page 4 sur 40Aller à la page : Précédent  1, 2, 3, 4, 5 ... 22 ... 40  Suivant
 Sujets similaires
-
» [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 5)
» [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 1) (Locked)
» [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 3) (Locked)
» [GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 2) (Locked)

Permission de ce forum:Vous ne pouvez pas répondre aux sujets dans ce forum
 :: ACTUALITES :: [GP] :: [GP125 (et 250 Snif!)]-
Sauter vers: