Motorcycle Repair: YOST POWER TUBE, yost power tube, barnett clutch


Question
YES I HAVE A 2005 YAMAHA ROADSTAR 1700CC MIDNIGHT SILVERADO 102ci. I HAVE INSTALLED SEVERAL UPGRADES SUCH AS THE NEMESIS INTAKE MANIFOLD,42MM MIKUNI,BARONS BIG AIR INTAKE SYSTEM,DYAN COILS,DYNA IGNITION,31 FRONT TOOTH PULLEY,BARNETT CLUTCH AND 2 INTO 1 MONSTER PRO EXHAUST COATED WITH JET-HOT. I WAS WANTING TO KNOW HAVE YOU EVER HEARD OF THE YOST POWER TUBE? AND IF SO WILL IT MAKE A DIFFERENCE AT ALL IN THE WAY MY BIKE PERFORMS? THANKS BRIAN

Answer

Hi Brian,

The yost power tube just replaces your slide needle and the emulsion
tube under the main jet with a new setup that is better at
vaporizing the fuel. This breaks the fuel down into smaller
droplets or a mist that ignites and burns easier.

The advantages may be slight so don't expect too much.
It might smooth out throttle response a bit.

Tuning your bike well with your present setup will work almost as well.
Take your weather and elevation into account as bikes need different
tuning according to their location so all bikes will not benefit
from the same jetting etc.

Sea level requires a richer fuel mix than a bike at 6000 ft elevation
which would run on a leaner fuel setup.

The slide needle and emulsion jet affect 1/4 to 3/4 throttle openings the most
so that is what the Yost will most affect.

The YOST is well made but cost may not be worth the small changes it makes.

It has many small emulsion holes which can plug up easily so a clean fuel
system is a must.

Good luck whatever you choose.

WS
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