Have shot 80 hp nitro shot without fuel.

[75-1244721801]

today i tryd my hayabusa in dyno and the tryd 80 % of nitro and 100% of fuel. I had AFR under 10 Then we thinked that it's okey to try 100% nitro and fuel because the afr was 10. But the FUEL solenoid didn't open and about 5 sec the engine worked with 80 hp nitro shot without fuel. It' didnt detonate.

Now the engine can't keep up under 4000 rpm . It revs up okey and dosen't make any noises but dosent work under 4000 rpm.


I'm so hoppyng that the problem is in melted sparkplugs. But then the engine would not work on any rpm .

I had wiseco 13.1 pistons.



Edited By Korke on 1245268305

[PetriK]

so you have a wet kit and worst possble fault that one can have with the wet kit ?

Lets hope its the copper plugs... while the plugs are out the compression test may be a good idea.

Wisecos are known of weaker ringlands for nitrous applications. I had bought a kit but was then advised to use special order JE:s for my nitrous rig.

Nitrous will start to loose power below 9afr. 11.5 is friendly to your engine but good power.

[75-1244721801]

so you have a wet kit and worst possble fault that one can have with the wet kit ?

Lets hope its the copper plugs... while the plugs are out the compression test may be a good idea.

Wisecos are known of weaker ringlands for nitrous applications. I had bought a kit but was then advised to use special order JE:s for my nitrous rig.

Nitrous will start to loose power below 9afr. 11.5 is friendly to your engine but good power.

I have heard lot's of storys how the JE pistons are weak for turbo and nitro bikes ???

[jarim]

I have 84mm JEs as well and I have put nearly 10kg of NOS through the engine and runs still good. Don't know how Wisecos work but can absolutely recommend JE.

[tenhulttio]

I have heard lot's of storys how the JE pistons are weak for turbo and nitro bikes ???

My "old-fashioned" opinion is that all pistons are OK. More like marketing bullshit.
But if you are running lean, no matter who have made pistons and from what, they will melt away.
And spark plugs can have sort of damage, that they doesn't work on low revs anymore (not likely, but possible).
As PetriK advised, first compression test to see that cylinders are even. Next step would be endoscope research.

[PetriK]

Yes - there is always some rumours which are boosted by the personal choise being adviced by seller.

About pistons, lets check the facts - having compared wisecos and je:s side by side last year on my desk, je:s design on ringland area is much better than the wisecos particularly for nitrous use. Also the wiseco design on anti detonation groove may promote nikasil wear as it has been reported, but I dont have personal experience of that from long term use, only what I have been able to detect from the design itsef. Also have seen pins on both pistons failing on race applications. Therefore for nitrous use englargened oiling channels and stronger than stock pins should be selected. JE:s have a very good custom design service to ensure that the piston desing is up to e.g. the rev limit targets of the engine.

I can not have an opinion about the boosted designs for low compression engines as have not had those pistons at hand. Anyhow the boosted application pistons should be very different to nitrous and all motor applications - so maybe the rumours are because not a correct type of piston design was used if compared in same sentence ?

[75-1244721801]

the compression was 6 and lower. Took engine. The pistons were meleted a little and rings worned out.
Now the compression is 10 to 10,6.
Now i must go again to the dyno to get fuel map and then will see what numbers i have in the rear.