I was lookin to buy some new tires, and noticed that my front and back tires are different sizes on my 300 4x4. I was thinking then that the front and rear differentials must be geared differently. Then I started thinking that maybe the rims and tires my have something to do with it to even the ratio's out just right. So someone tell me, are the front and rear differentials geared the same, or differently.

 

They are different. I think the owners manual tells the ratio's. A friend of mine has 26x12x12 Super Swampers on his 300, and it is pretty hard to steer on hardpack, but seems to steer well in the mud.

 

Your gonna want to be careful about changing the tire sizes like your saying. Make sure the new tires you do get will be equally different in size than your stock ones, like if you go to a 27 inch tall tire in the rear from a 26, and your fronts are 25's you need to step them up to a 26. Adding an inch to the front and the rear, if you don't do it equally you could cause extra strain on the axles and tranny, it would push one set of wheels faster then the other, or pull depending on which tires are larger or smaller.

 

Thats exactly what I was thinking. I thought that I had better ask about that. I didn't think that the front and rear had the same ratio's because of the different tire sizes. Thats a bad design idea to me. I guess it works tho

 

Personal experience--I, and most people I know with 300s, run 25" vamps front and rear and have lift from Highlifter. I have run this since '77 with no problems. That is just a fact, not someone telling you "I heard or I think". If you are afraid of a problem, adjust your tire pressure so there is a discernable difference.

 

Knottrider,

Good Question. I first noticed this on a friends Suzuki 250 4x4. Unfortuantely, if you upsize the tires, you won't end up with the EXACT same ratio but don't worry. Example if front/rear is 23/24 inch tires, ratio is .9583 going up 1 inch on both is 24/25 = .96, 25/26 = .9615. So you can see that although mathematically the ratio isn't the same, it should be close enough. The ratio can be off more than this just due to air pressure difference, or even the fact that the tires probably do not have a ride height of exactly and even inch increment.

Just thought since we were talking ratios, somebody should throw out some numbers. I happened to have my calulator handy.

Yammer_Hummer
2000 Grizzly, I got an easy one, 25/25 = 1.00

 

The front and rear end definitely have different ratios. I had a Blackwater big tire kit on mine and they had a inch shorter tire on the front. I don't know the numerical ratio. If you kept the wheeler in dirt, mud or sand all the time I don't think it would matter if they were close to the same size--but, if you run in hardpack or pavement you could have a problem.

Gardner10

 

I ride an average of 45-60 minutes every day on hardpacked ground checking and feeding cows. Some of that is on concrete and asphalt. I just have not had any problems with the same size tires on the front and rear.

 

I am I have almost completely built but I called a miniature rock crawler I build a frame around 81 650 Suzuki used a 15 tooth drive gear and a 40 sprocket the differential I'm using is a front end out of a 500 Polaris and it will go at the most 10 miles an hour in 5th gear how can I make this thing go faster and I'm not talking just a little faster if I try and 18 tooth drive gear will that be enough

 

You would have been better starting a new thread, this one is all about using different size tyres front and rear on a 4WD Honda 300.

If you are using 15 tooth drive and 40 tooth driven, ratio is 40/15 or 2.67 to 1 reduction. Your 18 tooth would bring this down to 2.2 to 1 so probably under 14mph. If you were wanting say 20mph top speed, you would need to halve the ratio. I would be going for 15 engine and 20 diff sprocket to get the 1.33 to 1 ratio for that.