Home Forums Gear Horses and ATV's yamaha Ultramatic transmission opinions

I might be needing a 4X4 ATV and I will only buy one with lockers front and rear.

Yamaha is the leading manufacturer with this diff lock feature. Almost all the models offered with this have the Ultramatic transmission. I'm not anti auto transmission, but I am curious about the pulling torque, or low speed high torque output.
The Yamaha has a 2WD/4WD and diff lock selection.

Actually my Rokon is an auto Transmission and has tons of torque but it's nice to hear from others if this ultramatic has good powerful low speed pulling power and torque.

I do not own an ultramatic, but know several that do. As far as belt driven auto's they seem to hold up real well. I think all of Yammi's that are auto are called ultramatics so you have a pretty wide range of power to choose from. If you were looking in the 400-450 class the Grizzly 450 has a low range and plenty of torque, however the the 400 does not.

If you don't want to go the auto route but like the Yammi, the Big Bear is a 400 with semi-auto shift and it has the diff lock feature. This machine is made to pull and is bullet proof to boot.

I just bought three 2007 450 kodiaks for work. The belts go forever IF you use low range when appropriate. I don;t recommend the 350 or 400 models because they only have a high range, though they are otherwise decent machines.

the Kawasaki also has a good front diff-lock on a lever that you can just grab when the front needs more traction. the yamaha you have to either lock up before entering the mud/hill, or else stop and engage.

the belt/drive system is essentially the same as in a 150 hp snowmachine, so there is no durability issue. in low range they will generate enough torque to break axles (i've seen it happen on frozen up machines)

The ultramatic tranny provides constant belt tension unlike the cvt used by polaris,which constantly flexs and wears,not to mention slips easier.. If the ultramatic design had hit the market first you wouldn't have all the bad press about belt drives. Polaris earned that deserved bad reputation for belts and cvt.

Arctic cat runs a very similar belt design to the ultramatic and has real good durability.

The ultramatic was introduced in 1997 on the grizzly. I bought my first grizzly in 1999 and the dealer had two 97 grizzlies in the shop. A rancher owned both and had them in for service. One had a little over 19000 miles and the other had 14000 miles. They took the covers off both trannies while I was standing there. Both belts were still like new and well within spec.And that was the first time the tranny covers had been removed. Durability isn't an issue. I've got access to two differant mechanics that work on yamahas not to mention they both ride the hell out of yamaha atv's. Both swear up and down that they don't even pull the cover on the tranny until the quad has 5000 miles on it and then its usually not a belt issue,its a lube issue

The ultramatic tranny is considerably differant then a sleds belt drive. I can burn up sled belts all day long. A sleds belt drive is alot like a polaris cvt drive which is why belts are easier to burn up on a polaris. Especially when you get into the 700 and 800 models that produce good power.


The breather vents on the current Yamaha's are really good. I've had creek water over the handlebars on both of my grizzlies and never slipped a belt or took on water. The trannies also have easy drains on them if you did swamp it. Which you'd have one hell of a time swamping one.


Get a grizzly if you're going to buy one. You won't regret it and you will use all the power,wether you believe it now or not. I put on 3000 plus miles on an atv every year and I get to test ride all the latest models and brands. Can Am or bombardier has a [bleep] of power,but durability isn't there. Polaris is a nice stable ride but will nickel and dime you to death,plus a junk tranny. AC has good tranny design,and good features,but durability is no where near what yamaha has. Honda has set on their nuts for too long. Good durability,but everything else is sub par.

You're on the right track with the locker. Its the only way to go.

Wow Mr. Sledder......Great post, I'll have to go get this little 4X4 this weekend. It's the IRS model with the 350 engine. Your post was a great help to me.

I'm tellin' ya get the 700 griz.

I cannot imagine anything I would need that big one for. I owned a Fortrax 300 for about 8 years and it did everything I ever asked of it, One of my best friends has it right now and he won't sell it back to me! If I were to move up in size the 400 would be as large as I would go. However if the Fortrax 300 did everything I ever needed with an open diff then this full locker with 50 more CC's should work out just right. Plus full independant suspension and that clever drive train sealed life time braking system.

Maybe if I were using it full time for farm work the 700 would be a good choice. However for that cost I would rather buy a small John Deer tractor!

JJ,

I rode a Griz 350 and a Griz 400 and I thought the 350 had a little more grunt on the low end. Maybe not but that is how it felt. I thought it was a better price than the 400 because there was not a lot of difference between the two. I think you'll like it.

The only tranny problems I had with one was a first-year model 600 Grizzly that I ran super hot (air-cooled) and then hit a deep water hole. I suppose the expansion and contraction of the metals allowed water to get in as the belts began to slip like crazy and we had to tow it back to the trailer. The dealership said the model has been experiencing these problems and that a new seal or case would be installed. Never had any tranny problems after that. I would really prefer a low range option on a mid-size bike with auto tranny just for the granny-low situations.

it sort of strikes me as bass-ackwards that the big bore quads have a sub-tranny with low range and the mid-small displacement machines do not.

jj if you don't want the 700 and once you have it you will rethink your position at least get the 450 Big difference between that and the other two for example hi/lo range. that
is a requirement as well for me.

OK...........I bought the 450 Grizzly

After looking them over and riding them a bit it became very clear that the extra 650 bucks to go from 350 to 450 with the electrical outlet, high/low range, digital display, and the exact same physical size made the bigger engine the right choice.

450 auto with diff lock and on the fly 2WD/4WD is a hella lotta machine! In low range with the diff lock it's a freakin tank!Thanks for the feedback and saving me from a big mistake!

Excellent choice! My forester buddy who has one is a big guy at 6'3" and is abnormally hard on all things mechanical. Nobody will loan him a vehicle of any kind (we know better). If he can't tear his 450 up using it almost daily, it must be a decent machine. My father is also a forester and runs the 660, the high/low and lockers get used often. He loves it.

You did good. I think you will really like it. For the price and in that range it is a hard one to beat!!!!

Great choice. You WILL like it. The low range really helps when you need it. The salesman at one dealer we look at tried to talk me out of the low range saying I will never need it, When in fact I used it yesterday.

You got a great machine...VERY reliable

tzone

A friend of mine has a 450. His even came with maxxis 6 ply tires instead of the dunflops.What did yours come with JJ?

His 450 hangs with the 660 real well.

Mine has hidious Maxxis tires that are so cheap they are not even listed as a tire on the Maxxis website!

I will be swapping these out ASAP for something else. My concern is tire weight. Most of the better tires weight about 40% more. I sure don't want to lose anything on the bottom end. I need to haul a meat trailer up steep hills, or have meat on the racks up those same hills. I'm talking Bison not deer. So you can see the weight I'm hauling could be plenty high!

I have used the Bighorn radials on my Rokon and they were spectacular. But they are also heavy. I'm not convinced I should go to the 26" tire, but the 25" size has limited width choices.

I may just stick with the bighorns in stock size. They run much bigger then they are marked. When My Rokon was parked next to my Griz, both with 25X8X12 tires the bighorns were massivly larger.

ITP has Mud Lites in the 25X10X12 for the front and a 25X12X12 for the rear, They are the same weight as the Maxxis bighorns. These are nice wide tires but staying with the 25" height. In either case they will be going on Black Sportlock ITP wheels

two of the 450 kodiaks have 26" mud-lite XL's (you can buy mudlites in an AT 3/4" lug and the Xt which is 1-1/2" lug). These two machines won;t ever see much use on forest roads, but burning around on them compared to the one with stock tires there is a significant loss in acceeration. In low range or off-road it is not an issue as far as acceleration, but it is noticeably more difficult to try and pop the front end up over a log or bank, I suppose a combination of the tire height and the few extra pnds in the front end. If they were my own machines and weren;t around so much rock, I'd definitely use aluminum wheels to offset the extra weight

Supposedly the bighorns are true to size or slightly larger.

Have you used the bighorns in snow much? How do they do.

And I'd stick with the 25" tire to help with weight.