i was going to drop a tooth on a front sprocket for more low end on my scrambler 400 4x4 but i have been reading this will mess up gearing is this true

 

yes it will mess up your 4x4.

 

Not trying to start an argument here but, Ive been running a 400 4x4 since 98, And Ive run 13-36, 12-36, 13-38, even 12-38... Ive also run 22" 24" and 25" rear tires and have never had a 4x4 prob. (knock on wood)
Rite now Im using 13-34 with 24 rears 23 fronts
Just my 2c

 

dropping one tooth should be fine. all it will do is make your front shafts spin faster in the front hubs. just make sure you have oil in the hubs or it could possibly sieze up and jerk the wheel out of your hand. if it siezes up you will probably take more damage than the machine does unless you are going 50 down a paved road and it locks up. then it will be about the same. :-) hope to be of some help.

 

I been doing it for over a year with no problems

We've had several good discussions on the consequenses and so far they are all just speculation. The real question revolves around how the front hub reaaly works.

My theory is that as long as rear tire travels farther with one rotation of the output shaft then the front you will be ok.

 

its not just speculation. i saw it happen to a good friend of mine.

 

it took him and threw him into a guard rail at 60 miles an hour. he broke 10 ribs in multiple places and his shoulder. his lung almost collapsed because of a "speculation". he also had 1 inch bigger tires on the back. and it couldnt have been electrical either because i plugged in the wires after the wreck and they were unplugged to begin with. i know because the four wheel drive never worked to begin with. i know exactly how those front hubs work. keep oil in them. it will be fine.

 

I am trying to figure out how the front shaft would spin faster. Nothing changed in the ratio to the front shaft. The rear axle will spin slower. Everything else being the same the ATV should go slower. I agree if the hubs run dry then they could sieze, but that would happen in the stock configuration also.

 

A friend of mine had his kick in at high speed also. He didnt wreck, but it was close.
Come to find out the hub was dry. All the oil leaked out over the summer, and he didnt check em.

 

its all a ratio. if you have a smaller sprocket the tranny spins faster to go the same speed. right? its direct drive from the tranny to the front drive shafts. that how they would spin faster.