Been there !
Luckily in the Summer.

Mike

 

Have you had any luck figuring out the problem?

 

No luck yet.

I removed the exhaust, double checked all joints, used hi-temp silicone, added new gaskets, no help. I was thinking about the gasoline coming from breather tube, changed oils and there was some gasoline among the oil.

Yesterday I removed the throttle body and the seals were ok. When I removed the throttle body I noticed that there's lots of oily black stuff inside throttle body and intake ports. At this point I was ready to give up, because first impression was that there's something really badly wrong with the engine.

After sleeping over night (saw really interesting exploding motor dreams btw.) I was thinking that there cannot be something that badly wrong with engine, it runs well without any excessive noises, no blue smoke or anything. So now there's two things on my mind:
1. Tune is badly wrong, at least on idle and it sputters (is that a word?) in to the intake.
2. I have been tuning with Thundermax a lot (bike not running, ignition on) if I have a leaking injector, and lots of gasoline has leaked to engine and mixed with oil? I think this would also explain why the back cylinder is running lean, as suggested here. TB is new SE 50mm.
I have the throttle body on the table now, is there any way to check the injectors?
If I blow to TB:s fuel line tube, should the air go through or not?
What do you think?

Thank You for the help!

 

You had gas coming out of your external breather and found what might be gas in your oil.

Unless I'm thinking of this wrong, the only way for that to happen is for the gas to come from an injector, run into the head from the throttle body and then leak past the rings into the engine.

It looks like everything is pointing to a bad injector. It leaks excess fuel at some point but runs lean when it's idling. I don't know what else to think. I'm just a self tonight mechanic that likes to learn more as I go. I'm sorry I'm not more help.

I wonder what Fuel Moto would have to say about this, I have to believe they've seen it all when it comes to engine and engine control problems.

 

Hi, some updates.
I had the injectors checked and measured and no problems there, everything worked as they should. Changed new intake seals also => no change.

At this point I was running out of ideas. I managed to reserve time from the local dyno shop http://www.hestec.fi/english/ they are mostly doing cars and had no experience with Thundermax but they have a really strong reputation here in Finland, and said that if it's a tuning thing, they can get it running right, no matter what's the system.

Spent the better part of the day there yesterday, and finally the bike is running as it should! . Turned out that problem was with my exhaust pipes. There wasn't any leaks but the left side pipe from the original 2007 head pipe splits from the main pipe before the O2 sensor, and with high lift cams with a lot of overlap, the air starts to move back and forth inside the left pipe and that screws up the sensor info, and with Autotune on, Thundermax screws up the whole system trying to correct the rear cylinder. This “back-draft” was also causing the black oily stuff, inside my intake ports. We closed up the left pipe, and the o2 sensor information straightened immediately.

They tuned the basemap quite a lot, and switched the Autotune back on and bike seemed to run fine, and also the Autotune was running as it should. I didn't want to strain the engine too much and we didn't pull the peak power out of it, but it was obvious that the engine is making serious power, 130tq at 3000 and 109hp at 5000rpm!! Power-curve was going straight up at 5000rpm when we cut it down, so with a better exhaust the peak hp will much higher now it's using just the right side muffler.

It was +2C and raining hard yesterday when I rode it home from the dyno, but there was a wide grin on my face
So it was a bit of a struggle but finally everything seems to work as they should, thanks for the help for everyone here!

Br Sami

 

I'm glad to hear you got it working. This is another example why it's important to upgrade your exhaust when you build up your engine. Where are the oxygen sensors located on your head pipe? They should be close to the head. I think 4 to 6 inches from the exhaust port.