[Mulvaney]

heys guys thanks for the help in advance. i am running a 900 kawasaki and was wandering since i can't get the front sprocket off if there is any way to copensate for it with the back one? i have a 16 on the front and a 54 on the rear and i need to get somewhere around 14 on the front and 51 on the rear ratio can it be done? how big would i have to go to get the same ratio? thanks

[dant]

59 to 60 tooth rear sprocket ball park

[TQ29m]

Good rule of thumb, from my old karting days, 1 tooth on the front, is about the same as 4 on the back, so if you take or add one on the front, that's close to removing or adding 4 to the back, same thing Dant said. Bob!

[DAD]

54 divided by 16 equals 3.38 to one
51 divided by 14 equals 3.64 to one
take the size of your front sprocket and mutply by 3.64 and you get rear sprocket size but you will be way off probably.

16 times 3.64 equals 58.24 teeth you arent taking the trans ratio and primary ratio into account. In second gear that is probably about 3.5 to run (3.64 times 3.5) is 12.88 to one way too low for that track. Get a manual for your motor. Look in specs. Get primary gear ratio and second gear ratio multiply primary by second gear times sprocket ratio get you your final ratio. We run about 12 to one at little salem.

[Mulvaney]

hey dad if i understood you correct i am runnung about 11.245 to 1
that is primary 1.714 times 2nd 1.94 times gear ratio 54/16(3.375)so now how do i get to 12 thanks

[dant]

Hey ...come on guys//when I started racing they said there would'nt be any math problems

[DAD]

****************CROSS MULTIPLY AND DIVIDE-------------------------
Good racers pay attention in school it ashame school don't have many racer teachers.


9500 rpm is to 11.25 as

12000rpm is to X (what I want to know)

12000 x 11.25 = 135000

135000 divided by 9500 = 14.21 to one gear ratio needed to get to your desired rpm if the motor will do it. That should be like running in 1st gear.




The 14/51 gear is equal to 3.64 x 3.32 (ratio in second) = 12.08 to one

the 16/54 gear is equal to 3.38 x 3.32 (ratio second) = 11.22 to one

this would require 16/58 3.63 x 3.32 (ratio second) = 12.03 to one or

16/59 = 3.688 x 3.32 (ratio second) = 12.24 to one You pick probably need to talk about that front sprocket and fold over washer and impact wrench now. Check your gears again because this seems more like a 3rd gear ratio # that you are giving me.

Now would be a good time to go back and thank that math teacher for teaching you something you can use, It would have been a lot easier for you to do math if you could have seen the use for it in racing in the future.


If you could change the front sprocket to 15 teeth. 54 divided by 15 = 3.6 x 3.32(second gear ratio) equals 11.95 to 1.

DAD

PS. "Dant" when did "Big Daddy Roth" get a ride in a 270 sidewinder or is that ol "Rat Fink" in there?

[dant]

Actually 'Dad'.. the picture was drawn by a artist Who saw me race [410 sprint]...I was a one man team -brought the car to the track -ran it solo without a crew...the announcer always made note of that all night long..so low and behold one night this stranger presented this to me as a gift..he was influenced by rat fink and i never mentioned that we were direct drive [no shifter] the drawing is odd ..but so am i..so it fits

[DAD]

Rat Fink needs the shifter, sure looks like a stinger for a tail pipe, you have to be 50+ just to know ol Rat Fink. I bet I drew 10,000 of these things when I was younger. You don't have to be odd to race but it sure help. The only guy I know who could move a sprint by himself was Roy Robbins I called him Sir.

"What me Worry!" DAD