4 speed/5 speed/or 6 speed, what do u prefer

the 6 speed is only in the yz 125, the yz 250 has a 5 speed. had it tapped out today btw! the 5 spd gives plenty of gear for the 250! :banghead:

So basically looking at those ratios, you can sum it up as this. The 426 in first gear has a lower ratio, then is close in 4th gear, but then you have the 5th gear that is below a 1:1 ratio effectively making it an overdrive.

Basically just like stated. But on a MX track, you never use 5th unless you are at a place like Honey Lake. 5th makes the bike more versatile to a wider variety of riders (from SX, to MX to offroad)

There's a little more to it, however. You cannot compare the two properly unless you examine the overall gear ratios in each gear, since in the end, that's all that matters. The 426 has a different primary reduction ratio (lower) than the 450's (and the 05 was higher yet than the '03/'04), and as delivered, also has a lower final ratio. Stock for stock the overall ratios look like this:

YZ426: 19.073 15.839 13.204 11.272 9.836

YZ450: 18.637 15.101 12.348 10.145

So, the stock final ratio of a YZ450 in top gear is over 96% as tall as the 5th gear in a YZ426. Most people I know who ride 450's in the desert or even in MX, gear the bike higher than stock anyway. Usually, they go two or three teeth off at the rear, or the equivalent. Mine is geared 15/49, which is the same as 14/46 (more or less), or two teeth off the back. That gives me the following comparison to a stock 426:

YZ426: 19.073 15.839 13.204 11.272 9.836

YZ450: 17.757 14.388 11.765 9.666

As you can see, it's damn near the same in top gear, and the other 4 are sort of stuffed between the 5 of the older bike. Low gear is a bit tall with this setup, but not as bad as it looks; 17.757 is 93% as low as 19.073. The massive torque of the 450 lets me get away with it pretty easily, and the only thing I have to watch out for is running it so slow that it suddenly decides to reverse direction in a tight spot. :banghead:

The concept of "overdrive" is often a bit misleading. It's a left over automotive term that comes from the fact that for most of the 20th century, standard practice was to have top gear in an automobile transmission, whether manual or automatic, be a direct, straight line coupling of the input and output shafts, resulting in a one-to-one ratio involving no gears. Such an arrangement is not possible in most modern motorcycles, because they generally don't have concentric input and output shafts, although, at one time, that was common. Overdrives were usually a separate transmission unit built to add on to the back of the main transmission, and when engaged, produced ratios below 1:1, giving the driver a gear high than, or "over" drive. In current motorcycle and even automotive practice, it's actually quite common to see 6 speeds with two gears at the end of the parade at less than 1:1, and fifth almost always is. But there again, even in cars, the overall ratio is still a reduction from the engine to the wheels.

My 4 speed is fine on the tracks over here in AUS but sometimes find I could use a fifth on some of the trails I ride, my mate always seems to blow by me when I run out of gears. I'd say if I had that extra gear he'd stay chopped...

i like the 4 gears. less shifting=-)

My preference is for the 4speed - for MX only.

The problem is Yamaha has been forced to keep up with Honda by going to a 5 speed to increase bike sales for everyone else that rides woods, desert etc....Marketing sux sometimes...I hope that the 07 WR is the same bike as the 06 YZF only setup for woods and a 5speed. I hope that Yami goes back to the 4speed for the YZF. :banghead:

I agree 100% with Ga426, BLEEP Honda and this whatever, sell more bikes bull excrement (what next we go to a unicam 80 hr switch 'er to stainless I do valve job's more than I ride horse shizit?), cater to real racers, provide us with a "true" MX bike, everybody else get a damn Wr., I have got a 00 426, and never get into 5th (at my local track), if I did I would constantly be landing flat and I would blow my front forks to hell. Cuz when "Nelly" comes on that Jardine it ain't no bullsheit.

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