TW125/TW200 - Dynojet Perfomance Test

[macbig2k1]

Hello,

I made today (Saturday) some tests with a friend and his TW125 and my TW200 on a Dynojet Performace test stand (banc d'essai/banc d'épreuve).

The tested bikes:
Test 1
Bike: Yamaha TW125
Type: DE01
Engine: 125ccm
Modifications: -----

Test 2
Bike: Yamaha TW125
Type: DE01
Engine: 125ccm
Modifications: Giannelli exhaust (nearly identical with the G.P.R. exhaust)

Test 3 (my bike)
Bike: Yamaha TW125
Type: DE01
Engine: 200ccm (cylinderhead, cylinder, crankshaft)
Modifications: high compression piston, Mikuni VM28-418, bigger outlet, YZ450F exhaust

Test 4 (from a Yamaha cataloge)
Bike: Yamaha TW200
Engine: 200ccm
Modifications: ---




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And here are the results:
Test 1
Bike: Yamaha TW125
Max. power: 11,42 PS/CH

Test 2
Bike: Yamaha TW125 with Giannelli exhaust
Max. power: 11,28 PS/CH

Test 3 (my bike)
Bike: Yamaha TW125@200ccm
Max. power: 18,90 PS/CH

Test 4 (from a Yamaha cataloge)
Bike: Yamaha TW200
Engine: 200ccm
Max. power: 16 PS/CH


You see, for the TW200 ~3PS/CH more power (with still 200 ccm) with a high compression piston (from 9,5:1 to 10,25:1), the Mikuni flatside carb and a optimised outlet.
My Mikuni is not perfect adjusted, the mixture is a bit too rich (too much fuel). I had some missfire on the test stand.


I will add soon some pictures from the test's.
Questions?

Salut, Sebastian

[george-le-yeti]

Yeah right man !! 

[george-le-yeti]

gianelli suck

[macbig2k1]

Why?
Just the max. performance is just 0,1kW (= 0,14 PS/CH) lower. But the performace is in the lower rpm 0,4-0,8kW (= 0,54-1,09 PS/CH) higher as with the org. exhaust.

Take a look on the Nm (just the TW125)




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The results:
Test 1
Bike: Yamaha TW125
Max. torque: 0,8 kgm = 7,848 Nm

Test 2
Bike: Yamaha TW125 with Giannelli exhaust
Max. torque: 0,82 kgm = 8,044 Nm
Max. raise torque: +0,19 kgm = +1,864 Nm -> +13%


Result: Giannelli does not suck!
You have to look on the complete rpm range, not just the max performance. You will have compareable results with all the other exhaust systems on the market.

[Taitai]

Thanks a lot, Mac ! Very interresting to have some real tests, not just reports based on the driver's sensations...
The modifications you made on your 200 ccm are just using quality/performing parts without changing the ccm ? Do you think possible to have gain just by changing the piston and exhaust, and enlarge the exhaust valve hole ? What is the risk with the original breech when using a high compression piston ?

Don't hesitate, if you can make some comparative tests it's very interresting ! Keep in touch...

[yan]

Don't hesitate, if you can make some comparative tests it's very interresting ! Keep in touch...

Là on sent le mec qui va avoir un peu plus de temps pour bidouiller sa TW 

[nico-dem]

Là on sent le mec qui va avoir un peu plus de temps pour bidouiller sa TW 

j'dirais plutot que ça sent le démontage vu qu'il a une brele de remplacement  , n'est - il pas ?

[warnours]

Là on sent le mec qui va avoir un peu plus de temps pour bidouiller sa TW 

j'dirais plutot que ça sent le démontage vu qu'il a une brele de remplacement  , n'est - il pas ?

les deux en fait , y va la perfectionné et la bichonner sa tite 200 ésperont .
La brelle de remplacement est quand même très pratique pour pouvoir passer du temps sur sa tiwie. y'en a qui on de la chance d'avoir plusieurs brelle , même qui en a qui en on plus de deux....

[Taitai]

Là on sent le mec qui va avoir un peu plus de temps pour bidouiller sa TW 

Zut, ça s'est vu ?! 

[macbig2k1]

Là on sent le mec qui va avoir un peu plus de temps pour bidouiller sa TW 

Hmm...not realy.
It's always the time after the work or the weekend. Not to have a girlfriend saves time

Thanks a lot, Mac ! Very interresting to have some real tests, not just reports based on the driver's sensations...
The modifications you made on your 200 ccm are just using quality/performing parts without changing the ccm ? Do you think possible to have gain just by changing the piston and exhaust, and enlarge the exhaust valve hole ? What is the risk with the original breech when using a high compression piston ?

Don't hesitate, if you can make some comparative tests it's very interresting ! Keep in touch...

The ccm upgrade was very small (from 196,4 to 199,3), because I use the 67,5mm piston, because the cylinder was very old.
A 10,25:1 compression isn't very high, if you compare it with a YZ450 with a 12,5:1 compression.
I made just these (for the engine important) changes:
- open airbox (http://yamaha.tw.free.fr/filtre_boite_air_tw.htm#boite)
- Mikuni VM28-418 (kit: 125_VM28_1)
- 10,25:1 piston
- bigger outlet
- open exhaust

-> That is everything

My engine works fine, no problems.

[stepf321]

Heuuuu...! comment dire , A oui je parle pas anglais, Hé oui c'est un site Français ICI, Hein ?
C'est dommage, parceque je serai intéréssé par la sujet.

[yan]

Heuuuu...! comment dire , A oui je parle pas anglais, Hé oui c'est un site Français ICI, Hein ?
C'est dommage, parceque je serai intéréssé par la sujet.

Disons que lorsque des Tiwistes allemands ont des choses à expliquer, ils préfèrent le faire en anglais qu'en allemand.

Quelle partie t'intéresse, que l'on puisse te la traduire (enfin si on y arrive, parce que les courbes de couple, ce n'est pas trop mon fort  )?

[5star]

Christddel cést un vrais specialiste  pas seulement en mecanno !
Christddel  is een echte specialist niet enkel in de mekaniek !

[george-le-yeti]

Sorry for the mistake Macbig, I thougth test1 is with Ginaelli.. It's wrong sorry.
Gianelli is better.

[macbig2k1]

It's OK.