13T too much

[stang9gt]

Have an 05 400EX, the 13T front is just too low for my type of riding. Its great for slower trails and play areas but sucks for high speed trails and the township roads we ride on around Pa. Thinking about going back to the stock 14T front and running a 37T rear. Will this kind of be a compromise between the 13T front and 14T front?

[procircuit406ex]

The 13/39 is a good setup

[stang9gt]

Originally posted by procircuit406ex
The 13/39 is a good setup

That is what i have now. 39 is stock for the rear on the 05. I am reving too high just cruisin around on the open trails.

[j450rking]

a 14t front and a 37t rear would be about the halfway point in between 13t and 14t so that should work pretty good

[procircuit406ex]

Originally posted by stang9gt
That is what i have now. 39 is stock for the rear on the 05. I am reving too high just cruisin around on the open trails.

Umm no its not. The 2005 400ex's have 14/38 gearing out the door.;)

[lpmaster]

05's have 14/39 gearing otd actually

a 14/37 is taller than stock and much taller than 13/39 so how is it halfway between?

[procircuit406ex]

Ok sorry that I doubted you when I am sitting here counting the teeth on it, but Im wrong it is 39.:rolleyes:

change front cause its cheeper and works better. Go 1 tooth up in front.

[Eviltanker]

My 06' is 14/38 and it works great.

older 400ex's i thought had 15/38 and newer 400ex's i thought had 14/39 :confused:

[underpowered]

Originally posted by j450rking
a 14t front and a 37t rear would be about the halfway point in between 13t and 14t so that should work pretty good

not quite. going up in the front is same as going down in the rear and up in the rear is same as goind down in teh front. so you would want like 13/37, 13/38, or 14/40, 14/41 to be about halfway between 13/39 and 14/39. 1 tooth up from is equal to about 2-3 in the rear.

[procircuit406ex]

Originally posted by LTD
older 400ex's i thought had 15/38 and newer 400ex's i thought had 14/39 :confused:

NO, the new models have 14/38 and older is 15/39.

[400exfan19]

u guys r all wrong, im not sure bout the newer models but im sure that the older 1ns are 15/38

[procircuit406ex]

Ok I give up, me and my friend counted the teeth on his sprockets on his 04 and then the teeth on my 05.

2004- 15/39
2005- 14/38

But bi God you all think what you want to...:scary:

[lpmaster]

you dont need to count them, the number of teeth is engraved on the side of the sprocket

99-04 15/38
05 14/39

06+ i dont lknow

[northwest Texas]

Okay, a 14/39 gives a final drive ratio of 2.79:1. A 13/39 gives you a FDR of 3.00:1

That's a pretty small range to stay in and here's what fits in between those two ratio's.

14/41 2.93:1
15/44 2.93:1
13/38 2.92:1
12/35 2.92:1
15/43 2.87:1
14/40 2.86:1
13/37 2.85:1
15/42 2.80:1


Pick your poison and good luck to you.

To add to the confusion here's some more

15/38 2.53:1
14/36 2.57:1
15/39 2.60:1
13/34 2.62:1
14/37 2.64:1
15/40 2.67:1
13/35 2.69:1
14/38 2.71:1
15/41 2.73:1
13/36 2.77:1


Just remember, in case you don't already know, that the lower the FDR, the faster the top speed while sacrificing bottom end power and vice versa for the larger the FDR number.

[j450rking]

Originally posted by underpowered
not quite. going up in the front is same as going down in the rear and up in the rear is same as goind down in teh front. so you would want like 13/37, 13/38, or 14/40, 14/41 to be about halfway between 13/39 and 14/39. 1 tooth up from is equal to about 2-3 in the rear.


yeah sorry had it mixed up my bad

[AZ_TRX400EX]

I run 15/38 and have a ton of top end (FDR of 2.53:1)
. I also do not notice any real loss of bottom end (torque).:blah:

[450Rchaser]

I'm puttin a 13T on my 416ex. I want low end. Don't care about top end. I want that hard grunt why i gun it in like 3rd and 4th gear.

[250X_project]

I agree 100%. I don't care how fast it goes, just how snappy it is.

So you can go from 227 - 366 on a 400EX?

[anderson3064]

Originally posted by 450Rchaser
I'm puttin a 13T on my 416ex. I want low end. Don't care about top end. I want that hard grunt why i gun it in like 3rd and 4th gear.

exactly what im thinking, i trail ride in tight trails. I dont think i have ever hit 4th or 5th except on the country roads getting to trails.