# The Dinasaur



## tlhtr (Apr 1, 2009)

Hi folks,
I've been lurking for a while and am in need of some help. I have a YM 336d and have aquired all the manuals, IE; owners, parts, and a dealers service manual (which has been a godsend). I needed to replace the front tires so I looked in the manual and then looked at what was on the YM, didn't match so I did some digging. The problem is, I found info on rolling circumference ratio and even the tires listed in the book have too much lag, IF I use the ratio (frt AXLE to rr AXLE speed ratio) listed in the service manual. There are several different ratios listed. If I use the listed front to rear axle ratio (1.4848) times the the frt drive shaft GEAR-to-BEVEL PINION reduction ratio (1.2) I come up with a good actual ratio of 1.78. If use that ratio I get a lead of 6 % which according to the info I dug up is fine. Any one know if what I have done is correct?


----------



## winston (Aug 19, 2008)

Sounds about right to me. My 226/220 manual gives a front axle to rear axle speed ratio in the back of the book under specifications. 1.743. Right under that is "Front Wheel Pre-run percent" 1 to 4%, over a little further to the right is a column for "wear limit" and it has 0 and 6%. Not sure what all that means. you probably do.


----------



## tlhtr (Apr 1, 2009)

Thanks for the reply. My book also lists pre-run of 1-4% and a wear llimit of 6% also. There wasn't any way a person could get the proper lead with the 1.4848 ratio when using the listed 8-16 fronts and 13.6-28 rears. I read that no lag is acceptable and can cause hard steering. I won't ever go on hard pavement. (as there isn't any for miles of my place). Still, I've read that to much lag can also stress the trans. 
I already have broken the tractor in half to remove the transmission and replace some bearings and a bad main drive shaft and couplings. Comes apart pretty easy, but man o man getting it back together again is a job. Rube Goldberg doesn't have any thing on me when it comes to makeshift "A" frames to lift it up.


----------

