Choose the language.
Tkart magazine

True or False | 6 quizzes on the optimal ratio of your kart

go down go up
ENGINE PERFORMANCE
TRACK CONDITIONS
PINION WEAR
kart
quiz
START
SEARCH FOR THE OPTIMAL RATIO
COMPOUNDS
GEAR WHEEL
THERE IS NO DIFFERENCE IN ENGINE PERFORMANCE USING TWO EQUAL RATIOS BUT WITH DIFFERENT GEAR WHEELS AND SPROCKETS
Answer
Andrea Bossaglia
IAME Engineer
or
Next question
WELL DONE!

With the same ratio, it is the mass of the rotating parts (pinion, gear wheel and chain) that is different and affects engine performance. Let’s compare, for example, the “pinion 10/gear wheel 89” and “pinion 9/gear wheel 80” pairs (where the numbers represent the number of teeth). With the same substantial ratio, the sprocket/gear wheel composition with fewer teeth causes the engine to behave as if the ratio is a little shorter, that is, the engine will have a minimum extra tendency to reach high revs quickly, thus obtaining more torque on the axle. In this case, acceleration will be preferred over top speed. The opposite is true for the pinion/gear wheel composition with more teeth: the ratio in this case will be slightly longer, bringing the engine to work at slightly lower speeds, preferring the top speed compared to acceleration coming out of a bend.

WRONG!

With the same ratio, it is the mass of the rotating parts (pinion, gear wheel and chain) that is different and affects engine performance. Let’s compare, for example, the “pinion 10/gear wheel 89” and “pinion 9/gear wheel 80” pairs (where the numbers represent the number of teeth). With the same substantial ratio, the sprocket/gear wheel composition with fewer teeth causes the engine to behave as if the ratio is a little shorter, that is, the engine will have a minimum extra tendency to reach high revs quickly, thus obtaining more torque on the axle. In this case, acceleration will be preferred over top speed. The opposite is true for the pinion/gear wheel composition with more teeth: the ratio in this case will be slightly longer, bringing the engine to work at slightly lower speeds, preferring the top speed compared to acceleration coming out of a bend.

Continue reading your article

Don’t waste time: register now for a 24-hour free trial period. Unlimited articles.

Start your 24-hour free tour
No Credit Card required
or
Skip the free tour and become a TKART Magazine member now.
  • Constant updates
  • Interactive content (360°, Video, Gallery, etc.)
  • 15 sections
  • Over 600 in-depth articles
  • Access to the entire archive
  • Available in Italian, English and Spanish
  • Access from your desktop and mobile devices
Subscribe