Newbie Questions

That may be, but 50:1 has more gas than 25:1.

Richness is measured from the perspective of the oil not the gas. Gas is gas, but gas with oil is richer than gas without oil, therefore gas with more oil should be richer than gas with less oil, and gas where 50 parts are gas for each part of oil has less oil than gas where there is 25 parts of gas for each part of oil. 25:1 should be richer than 50:1 because there is more oil in it. 25:1 is the same as 50:2, and 50:2 has more oil than 50:1 by double the amount of oil.

Agreed... thanks for your input. ;-)

JimG

"CRWLR" wrote

50:1 has more gas, yes. The rest of your statement is incorrect.

Less oil means more fuel will enter through the same sized jet. More fuel in the fuel/air ratio means a richer mixture will enter the combustion chamber. One will have to jet smaller to achieve the same performance when going from 25:1 to 50:1. It may seem backwards but it's not.

Oil does not figure into the combustion, only the fuel and air. More fuel for the same amount of air equals a richer mixture. The oil is for lubrication and cooling.

Yes. Forget about the oil when considering the richness of mixture and concentrate on the fuel/air ratio. Oil is for lubrication and cooling of the internals. More oil = less fuel + same air = leaner. Less oil = more fuel + same air = richer.

Actually, forget about the air. We are talking about the ratio of oil to gas, not the mixture of fuel and air.

There is more oil in a 25:1 mixture than there is in a 50:1 mixture. We don't care what will run in a motor, we only care that the relationship of ratios is understood. The relationship of 3.73:1 gears vs. 4.56:1 gears is the inverse of a 25:1 oil/gas mixture vs. a 50:1 oil/gas mixture.

The higher numbers in the gear ratio means lower speed and more power, but the lower numbers in the oil/gas mixture means more oil. The analogy was first expressed as though the lower number meant less oil, but it means more oil.

No. Remove lubrication to the point that the motor is still adequately lubed but not spooging out the exhaust and then jet appropriately. In practice it's a bit of back and forth until you find the perfect balance. Using different oil will change the lube/spooge/jet equation. Some lubricate better, some burn more, so on.

"CRWLR" wrote

Not when you are talking about the richness of the mixture, you're not.

Gear ratio 3.73:1 is higher than 4.56:1 Fuel/oil Ratio 25:1 is leaner than 50:1

Trying to build an analogy using these two is not a good idea because they do not relate to each other. Try using pipes. Same pressure in big pipe versus small pipe ... fluid will flow faster in small pipe. Smaller number

• faster flow like the gearing.

My mistake, I used "richer" to describe that there is more oil in a 25:1 gas/oil mixture than in 50:1. This condition may not be richer, and I used the wrong word. In any event, the analogy is flawed when used to correlate gear ratios.

I was going to get out this conversation... but I can't help it :-)

When you say "higher" what do you mean? (It sounds like your saying "higher ratio")

This is the whole point of my argument... 3.73:1 is a lower "ratio" than

4.56:1 (ask your math teacher).

The OP (poor guy... all he wanted was a simple answer) asked: "1) How difficult and expensive would it be to go to a higher ratio? (addition to my wish list)"

And CRWLR wrote: "First, you want a lower ratio, which is a higher numeric value."

That's where I disagreed... The OP is correct in wanting a "higher" ring/pinion gear ratio which produces a more power to turn bigger tires, what we call a lower gear.

We all agree that 4.56:1 is a lower "gear" than 3.73:1

Agreed

JimG

Man we live in an interesting world. Yes, I meant flashlight but unfortunately it has been raining for the past 24 hours and I don't have a covered garage. I'll just have to wait.

TW

Thank you all for your input, this has been a learning experience for me. I do have other questions, but I think I will just wait for the weather to improve here and ask all of them in one post.

I had asked about the a/c went bending because on a couple of occasions I have had water drip down on my feet while driving in heavy rain and highway speeds. At present the a/c went is just a stubby little thing sticking out of the firewall. Any ideas or solutions. Thanks in advance.

TW

Think in terms of the transmission. 1st gear, the lowest gear is probably something on the order of 4.22:1. The engine and input shaft go around 4.22 times for 1 revolution of the output shaft. The highest gear is 5th, with a ratio of about .73 to 1, where the input shaft goes around less than once for each revolution of the output shaft.

Every time you select a new gear (by shifting), you effectively do the same thing as a R&P swap. If you do an R&P swap to a higher numerical value (changinf from 3.07s to 4.56s, for example), you are downshifting to a lower gear. Obviously regearing the diffs and downshifting are not the same at all, but for the purposes of illustrating the higher and lower gear ratios, it works reasonably well. If you had to drive around in 1st all day, you couldn't go very fast, but you would have gobs of power, and if you had to drive around in 5th all day, starting going would be painful indeed, but you could go as fast as you wanted.

Regearing the diffs to lower gear ratios allows you to go slower in a low gear than you would otherwise go, but it also limits the top speed. What it does in the middle though is it raises the engine speed relative to the ground speed in order to get the power band back to a normal location after getting larger tires. If you regeared the diffs to a lower ratio, but retained the original tire size, you would find that you could not maintain the same cruising speed as before. You get the crusing speed back by regearing after larger tires are installed. What happens with the larger tires is that the engine speed drops relative to the ground speed, and it can drop so low as to be outside of the power band. Without regearing, and installing larger tires, you might find that going slow is difficult, and

5th gear no longer works because the power band is gone in that gear.

I had an AC that dripped once, the hose was plugged with a ball of lint. Kind of like belly button lint on steroids.

Wait for what? Just fire up that torch and go check the gas tank. You'll be warm enough soon ... :-)

I understand all of that... you obviously are not comprehending a word I write. By :-)

JimG

I worked in a 2 stroke bike shop for a couple years and we always used the term 'richer' for the 25:1 mix and 'lean' for the 35 or 50:1 mix.

It is a richer oil mix. This is also the way the manuals state it.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Lower gears have higher numbers. You have repeatedly expressed that this is curious. I am only trying to draw analogies that remove the curiosity. Sorry if I have offended you.

Bye. :-)