sprocket sizes?

[randallp1]

i have a 426 11:1 (for now i want the 13:1), port polish, stg 2 magnum cam, stock carb and im wondering what sprokets to change to. im into drag racing and i find i have the holeshot on top of everyperson i race against just can keep up after 1/2 distance. i see this MORE SPEED 16tooth sprocket and i want to change to it but a 15 tooth would it be too much? what about the rear sprocket?

[BluBeaSSt]

you need less teeth would give you top end, if you have a 16 tooth drop it down to 14 or 15, but remmeber that will take away from your holeshot

[oleboy87]

to get more top end ya can go up one in the front and down in the back depending on how much you want to go... i THINK but not sure going up one in the front is equivalent to going 2 or 3 teeth down in the back going down in the back is jsut not as drastic as going up in front

yea i think have it right but if someone see different just correct me...

[drew416ex]

To hear it up for more top end you go up in front and down in back. 1 tooth difference up front equals about 2 on the rear.

[oleboy87]

yep he said it way better than me

[randallp1]

so what can i just change 1 tooth in the rear and give me a little more top end? how much do you think i will lose from my hole shot?

[BluBeaSSt]

Originally posted by randallp1
so what can i just change 1 tooth in the rear and give me a little more top end? how much do you think i will lose from my hole shot?

It depends, how bad are you getting beat up top? like 2-3 bikes?

[drew416ex]

What size rear tires do you have. If its 20" i would say try 1 tooth down on the rear. If you have 18" i would say 1 up on the front or 2 down on the rear.

[randallp1]

i can beat this suzuki 450s and the yamaha 450s at this spot by the house everytime. its a spillway and the drag strip is loose dirt and i run these 4snow tires. so im getting traction and they are spinning. but if any bike has motor work done or an extended swingarm then its like 2 bikes 3 at the most. then again not bragging but i run the piss out my bike and im prob the best at putting it down on the strip out the guys that i race. but i also drag in the sand too so i dont want to be weak off the line in the sand.

[chipworkz]

Originally posted by R_Hoaglin2
you need less teeth would give you top end, if you have a 16 tooth drop it down to 14 or 15, but remmeber that will take away from your holeshot

You got it backwards. Bigger in the front or smaller in the rear for more top speed.

Here is a gear ratio chart courtesy of Renthal so you can see exactly what your changes will be.
Gear Ratio Chart (http://www.renthal.com/features/ratio.asp)

[randallp1]

no one answered me. if i change the rear to a 37 tooth would it be a waste? is one tooth even worth it?

[chipworkz]

Originally posted by randallp1
no one answered me. if i change the rear to a 37 tooth would it be a waste? is one tooth even worth it?
You never said what rear gear you have but I am guessing you have a 38 tooth. I personally wouldn't change the rear by only one tooth. I went one size bigger in the front and I did see a difference. It did take away from the snappiness on take off but not by a HUGE amount. Once I do some power mods I will also lower the rear gear two teeth to get even more top end.

[randallp1]

is it better to change the front or rear. if i go two lower in the rear then that would be going like 1 3/4 in the front?

[chipworkz]

I would prefer to change the rear because going bigger on the front can cause some clearance issues with the chain. You may need to modify your case saver and the chain will ride on the chain guide / roller more. I changed my front and tons of people do so it is up to you. If you do go bigger on the front you probably will need to add one link to your chain. Going smaller in the rear you may need to remove one link. It depends on how much adjustment you have to play with.

[espergre]

if you have motor work resulting in plenty of torque, which you do. A bigger front sprocket gear will not slow your take off as long as you can keep from spinning the tires. The bigger front sprocket increases your wheel rpm/motor rpm ratio. The wheel will spin faster in every gear compared to a smaller sprocket as long as your torque is not limiting you. To compensate for this you just need to adjust your shifting to stay in your torque powerband. I would recommend going up one tooth in the front, this will increase your top end by (16-15)/15 = (1/15) = 6.67% GOOD LUCK!

[randallp1]

as well as in the sand? so dont change the rear correct?

[espergre]

A different size sprocket will not guarantee a faster quad, especially in a drag race. Personally, I am faster with more top end, I tend to really wind out my gears, Others who shift sooner, find a smaller gear to really help with their acceleration but lack top end. I do just fine off the launch and keep from spinning. This leaves me with more top end to really pull away once in 3rd and 4th gears.
A good set of sand paddles will really help keep you from spinning the tires.

[Brauap]

Originally posted by R_Hoaglin2
you need less teeth would give you top end, if you have a 16 tooth drop it down to 14 or 15, but remmeber that will take away from your holeshot

not meaning to sound "harsh" but your 100% WRONG! Lower you go, more bottom end and better holeshots. Higher you go, more top end and worst holeshots, unless you have it bored out and can go through the gears fast with stock.

[espergre]

im not wrong, you are correct that a lower gearing will give you more torque, but as long as your motor has the power to move the wheels (torque), and you can avoid spinning, a bigger gear will have a faster takeoff. There is such a thing as being under or over geared. Depending on the power he is putting out, a small gear may not allow him to utilize his torque to the wheels fully.

[clhuff]

drop down to 14 in the fornt and put 18" tires on and start in 3rd gear

[drew416ex]

Originally posted by clhuff
drop down to 14 in the fornt and put 18" tires on and start in 3rd gear

Why would he want to do that? He wants more top end, doing that would kill the top end.

[clhuff]

yeah but depends on how far has to go