I am sailing a Tornado. Upwind it is very difficult to get the upper tell tales at the wind side streaming? I am not sailing too high as the low tell tales are all right. If I pull a lot of downhaul at the jib it improves. Sometimes it looks like the luff of the jib gets more loose when hard on downhaul and sheet of the main? Not very logic I think. Mastrotation has no influence. What can it be?

Try changing the point on the clew where the sheet connects. This will affect the amount of twist in the sail. It sounds like you have too much twist. Assuming you have a clew plate on the jib with multiple holes for connecting the sheet, I would attach the sheet to one of the holes higher up on the jib to put more sheeting force toward the top of the sail to reduce twist.

Jake's answer is spot on. Unfortunately some jibs don't have multiple adjustment points in the clew. Some others like the jib I am working with on a N20 as crew don't have a sweet spot. If I run in the normal position I have too much twist at the head. Moving 1 hole up and the sail is too flat. On this particular sail, I will use the lower hole to about 10 kts of breeze (just double trapping) as it gives the sail more belly. I go one hole up (contrary to what I would do with a new sail) as the breeze builds. This flattens the sail and prevents leech flutter upwind in bigger breeze. Again, not what I would do with a new or nearly new sail but its what works on this particular sail. Normally you would go one hole down to open the leech up and de-power the top of the sail, but if you don't have full battens or a stiff leech doing the opposite has proven faster.

Good luck.

yes, too much twist. Apart form changing the clew, less mast rake could be an option too.

Cheers,

Klaus

As Jake says if you have a clew plate (back corner of the sail) try the top hole. If you don't or if this doesn't fix it put a big shackle at the base of the jib to move the whole jib up the forestay. You are trying to make the jib sheet more vertical so any changes you make should have that goal in mind.

I sailed this weekend and changed to a higher hole. The problem was fixed. However in a gust all the tell tales at the wind side flutter upwards. Better to neglect this.

you are either experiencing a change of wind direction with the gust or you are pinching to depower. You should try to keep them flowing 90% of the time even through the gusts. Depower by manipulating the sails and downhaul but if you can keep the boat mostly on track through the gust, you will get speed in return for your efforts.

Right, and even if wind direction doesn't really change, apparent wind does, which explain why it is repeatable.

Correct, but too much steering gives a loss. You have to give the boat time to gain speed, so you have to sheet out.