Reviving A -99 Tdm 850

[anda3243]

Did you remember to drop the needles back down 1 notch to their original position? This is the most likely cause of your rich fuel/air imbalance when engine braking on part throttle.

 

Your airflow and fuelling will always be high if you are using an aftermarket filter and have altered the airbox like that. So you should expect to run lean to some degree.

Maybe return to the successful setup as a compromise? It got you around Europe so it can't be that bad!

 

Setups like this usually employ a dynojet kit for the carbs, using oddball needle profiles to finely fuel around airflow.

 

Needle position is more to do with where you are on the face of the planet Earth and how much oxygen there is available for your engine to burn.

High altitude - top notch/drop needle

Normal - middle range

Low altitude - bottom notch/raise needle. You'd have to be tuned to the max and have a big bore kit to need this.

 

I did not drop the needles. I only adjusted the idle screws. The bike is running much better with the needles in this higher position.

Now I have done another 500 km on mostly highway, and the problems with running rough are mostly gone. But I need to do more riding in city trafic to be sure.

I still have not had oportunity to measure compresion.

 

In Norway we were riding between sea level and 1000 and more meters above sea level. The bike was running good at both high and low altitudes.

The new needle position gave more power independent of the height above sea level.

I am thinking now that I need bigger main jets (155 or 160 instead of 150), and maybe drop the needles 1 or 2 notches.

 

One more thing that concerns me is that I have different markings on both needles. Should they be the same.

Right side needle marking: 6CLI

Left side needle marking: 6DJP