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diff ratio calculation...confused.com
AndyW - 16/9/15 at 08:17 PM

Hi all

just happened to check my diff ratio to eliminate an odd ratio from being a potential problem.

Now, with BOTH rear wheels off the ground I rotated the n/s and the diff flange didn't move. It only moved if I reversed the wheel rotation and tried again. I got 19.5 turns of the diff flange to 10 turns of the wheel but this was with the o/s wheel locked so it could not spin, that was the other way to get the n/s wheel to actually turn the diff flange.

Am I confusing my self, or should when either rear wheel turns the diff flange should turn? Even if you do it really slowly?

I'm going back out in the garage now to check a few more things so any advice welcome.

I will have my ipad with me to check for suggestions

TIA

Andy


cliftyhanger - 16/9/15 at 08:30 PM

3.9 ratio......
one wheel locked means the other turns twice as much. So both wheels would have turned 5 times.
19.5/5=3.9

[Edited on 16/9/15 by cliftyhanger]


dave_424 - 16/9/15 at 08:32 PM

Easier way, rotate the prop and count the wheel rotations


AndyW - 16/9/15 at 08:48 PM

I can get two rotations of the wheel to 1 rotation of diff flange. If I turn the wheel fairly slowly the diff flange doesn't move.


AndyW - 16/9/15 at 09:40 PM

I have checked the drive shafts and both connect ok.

So, should I be able to turn one rear wheel (the other spins in opposite direction) and get no movement from the diff input flange? Or should this always turn at the slightest move of the wheel?

HELP.......

Ta

Andy


dave_424 - 16/9/15 at 09:44 PM

Yes, turn one wheel, the other one counter rotates and the diff flange doesn't.


r1_pete - 17/9/15 at 06:43 AM

quote:
Originally posted by AndyW
I have checked the drive shafts and both connect ok.

So, should I be able to turn one rear wheel (the other spins in opposite direction) and get no movement from the diff input flange? Or should this always turn at the slightest move of the wheel?

HELP.......

Ta

Andy


Yes the planet gears reverse the opposite wheel if the pinion is locked, or has the most resistance to turning.

Nothing wrong there, & Cliftyhange's response is spot on....