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Messages - rustybutterknife

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Driveline / Re: Peerless 700 Gear Ratios?
« on: November 27, 2019, 11:31:34 am »
I think there seems to be some misinterpretation here.
When the previous posters were talking about 1:1 ratio, they are referring to one specific pair of gears in their trans, one each on the mainshaft and countershaft.
One will have the shift keys and the other will have the gears splined to be stationary on the shaft.

I did a parts lookup on your model transaxle you specified, and going with the same numbers as others running 700's, 4th gear in yours would be the 1:1 ratio. Your model then has a 3:1 reduction with the input. Then 16.5(total ratio of your 4th gear) divided by 3(input ratio) gives you a rear end ratio of 5.5 to 1.
The reason you didn't reach a 1:1 with any gear is that you calculated your total ratios from the input to the axleshaft, which includes the reduction of the input/bevel pair, and the extra reduction from the countershaft to the differential.
Take all the extra reductions out and we can figure the ratios of the 5 gears/reverse themselves.

1st- 3.03:1
2nd-2:1
3rd-1.21:1
4th- 1:1
5th-0.72:1
reverse-2.42:1

Now, there isn't anything wrong with having figured out the overall ratio here. If you are running a transaxle, which I take it you are, you can use the numbers you have to adjust your pulleys to fine tune your gearing based on track size.

Yes, I suppose I misunderstood the intent with that. I just assumed that the total ratio would be the most useful information so my chart shows the total ratios. I don't know what use beyond the whole transaxle as a unit, people would have for individual gear set ratios, unless we are changing the internals around. I more or less wanted others to know the pitfalls of counting rotations on the bench with an open diff and how it will muddy the results compared to what it should be, and also give a rough idea of what to expect for total ratio for selecting a pulley.
Thanks for the clarification on that,
-Josh
*edit, I went back and read through the whole thread and it makes a lot more sense now, Thanks!

2
Driveline / Re: Peerless 700 Gear Ratios?
« on: November 21, 2019, 03:16:12 pm »
It is easy to figure out yourself.  Just put it in each gear and turn the input shaft counting each full revolution in order to make the output turn 1 revolution.  The 1:1 gear set will be the gear which you need to turn the input 3 time in order to make the output turn 1.
I know this is an old post but I Stumbled across this in a google search. it was the impetus for me to do some work to try to understand how the ratios could be calculated and verified by counting rotations manually, so I felt like it might be worth resurrecting it.
 
Long story short, I took the tooth counts from the gears my transaxle and put it in all into a spreadsheet and did the math on it and for some reason it was not matching up to what i measured counting by hand. Turns out, that if you have an open diff (stock unit) and you haven't put a spool in it, or welded the gears, you will need to make adjustments to your rotation count. with one axle not spinning, the other will turn half the amount due to the 1:1 counter-rotations of the spider gears. So, if you are counting 6 rotations at the input shaft with one axle stationary with an open diff, it is actually 12:1 reduction. My 4150 5-speed ended up being as follows:

1st gear        50:1
2nd               33:1
3rd                20:1
4th             16.5:1
5th                12:1
Rev.               40:1 

Where the higher number is the rotations of the input pulley and the second is one rotation of the ring gear.
All it really takes is looking at the parts diagram, and using the tooth counts and dividing all of the input gears by the output gears in terms of mesh.

an example of this would be:
(1st pinion # teeth*1st gear input # teeth*spur gear # teeth*comb gear min # teeth)/(bevel gear # teeth*1st gear driven*comb gear maj # teeth*final drive ring gear # teeth)

which for me was:
(14*12*14*12)/(42*37*35*32) = 28224/1740480 = 1/62

Or:

0.02 in decimal form
which is 1/50

Hence 50:1

None of the gears were anywhere close to 1:1

Which can be verified by turning both axles together and back driving the input shaft to count rotations, or assembling the unit and making the turns at the input shaft with both wheels on the ground going straight, or by holding one axle still (non locker) and doubling the counts at the input shaft that gives you one turn of the free axle.

working with ratios in decimal form was a bit of a mind bender for me so it took some getting used to. I can provide the spreadsheet and the diagram I used if anyone wants to take a look.

From this, I was able to calculate the speed etc...

Hope that helps!

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Want To Buy / Who Has It? / looking for gas tank and steering wheel/hub
« on: November 21, 2019, 12:58:58 pm »
looking for a steering wheel with hub and a square tank for an 80's craftsman lawn tractor. something like these



Shipping to 47122

Thanks for looking,
-Josh

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