Variables

[jack1018]

Hi, My son and I have two identical 33cc stand ups. We went for a city block drag race and I found that mine accelerate quicker for the first 3/4 of the block and his has higher top end. We have the same weight. What are the variables to make them different. I used the same method to set the carbs and we burn the same gas and oil. thanks

[Dac]

maybe tire inflation ?

maybe spark plug ?

i dont know how new they are but it ever could be the air filter?

[MotorMaker]

Are they friction spindle drive?

[noiseguy]

Wow, a Goped on the forum.

I'll bet that there's a slight difference in the gearing from engine to wheel drive, with the slower accellerating scoot having a lower drive ratio

[jack1018]

They are chain drive with same gearing. The chains have the same tension. I tuned both of them at the same time before we raced. By the way, we have a 86 Honda Spree that I am trying to make it go faster. thanks[/img]

[keithw]

The two go-peds are mass produced with expected variances is tolerences. If you got ten together they would all be different. Also there are differences in wear and tear.

The Sprees are fun to work on. I'm about ready to do more speed runs and add to my "spree test bed for mods" string. Some of the common mods work and some not so much.

keithw

[MotorMaker]

With all things equal (including engine rpm) I would guess either Tire pressure or tire wear. A larger tire (higher pressure or less wear) will give you higher top speed with less take-off. Conversely a smaller tire (more wear or less pressure) would yield a better "hole-shot" but a lower top speed. Rider weight would also in effect change tire radius. This could be ruled out by switching scoots and running the same course again.