*the everything from scratch buggy- by voodoo*

[trans man]

WTF!!!!!

[Yummi]

Glad to see your out putting  some miles on her.

 


Vodoo - looks good.  Good to see you enjoying your hard work. 

[Voodoochikin04]

according to my gearing, on paper 101mph is my top speed.     with two people and a strong headwind I was hitting 86mph on the gps speedometer on my gf's phone..   feels plenty fast..

[fabr]

according to my gearing, on paper 101mph is my top speed.     with two people and a strong headwind I was hitting 86mph on the gps speedometer on my gf's phone..  feels plenty fast..

I'll bet!

[mr.bob]

how do you do the math to find out mph?

[Voodoochikin04]

ohh.. fabber posted a link like 30pages back in my thread i think... or maybe it was in another thread i posted..  you put in your gear ratios of each gear, tires diameter, engine rpms.. and such..

[mr.bob]

i was thinking all the gears had to be put in the calc.i have the link to a calc.but never looked for gear ratio on the motor.
sweet buggy ive been watching your vids for a wile,thats how i found this site.you should post some more.

[Voodoochikin04]

http://www.apexgarage.com/tech/gear_ratios.shtml

heres the link i used and a quote from masterfabber..

"I guess I should mention that the rpm value you use when working with a bike engine or any engine for that matter with a primary reduction is the engine rpm divided by the internal reduction ratio. In voodoos case his redline rpm is 13000 and his primary reduction is 1.744 so you use 7454 as the input rpm. I rounded his off to 7400. There is another variable that can and does make a difference also. Tire diameter is most often used in these calculators. IMO if you want better accuracy you need to measure out the ROLLOUT of the tire and then convert that circumference into diameter for the true tire height.  You may ask how a tire can be a certain height and not have its rollout(circumference) be mathmatically different. It has to do with how a tire contacts the ground. With some tires that run at low pressures(don't we all?) the rollout can be significantly different than the diameter would indicate. Best thing to do is adjust air pressure to running pressure and with the tire on buggy and with buggy at running weight make one revolution of the tire and measure the length of the "footprint" on the ground and convert that true ,real world, circumference into diameter and use that diameter in the calculator.  Yes,I know, low pressure tires grow with higher speeds (think top fuel dragsters)but our speeds will not make much difference. "

[mr.bob]

thanks thats better than the one i had.
http://www.compgoparts.com/TechnicalResources/SprocketCalculator.asp

are you using a 13/60 set up?

[Voodoochikin04]

currently using a 13front 60rear with 22" tall tires..   but as i found out, this same configuration is vastly different with different engines, due to the different ratios for each gear....through out different brands of engines.

with 13 front and 60 rear,, thats a final drive ratio of 4.61  (60/13=4.61)  think of it just like a cars rear end gears...

[mr.bob]

i have a 95 gsxr 750. i think it would be the same?

[Voodoochikin04]

your 1995 750 would be closer or the same to my original engine.. a 1995 suzuki gsxf-600. (katana) quite a bit different than my 2003 gsxr600..

[mr.bob]

oh i thought you had a 750

[Voodoochikin04]

nope..you susre you checked out my build log?? lol

[mr.bob]

i thought i did.to many buggy to read about