What is an Override trannsmission? I read some of you drag guys are using them.

 

The best way to describe it is, an override is made so that the only time you need the clutch is to launch the bike, and then again at shut down. Once you launch the bike, and its under full power, you can just click up through the gears with out using the clutch. But has to be pulling, if you will. You cant allow any back pressure, by letting off the gas, and letting the motor slow the bike down. It will bend the shift forks, and youll be done right then and there. Its a drag only mod.

The bike in this vid has an override, notice how it has continuous power to the wheels once its launched. You can here him shifting through the gears, but notice how the roost behind him is constant with no breaks in it.

YouTube - 2 004

Goodsound, I edited your message to show the You Tube Video you posted.

 

An override transmission is a stock tranny that has been modified so that it can be shifted without the clutch. You launch with the clutch and when its time to shift just pull up on the shifter...no clutch necessary. This shaves about 1 to 2 tenths of a second off of the 300ft time because the clutch stays fully engaged all the way down the track.

The way it works is when you shift, the tranny is temporarily in two gears at once. Once its in the higher gear the output shaft begins to spin faster and "overrides" the lower gear. The reason it does not crash is because the back side (coast down or throttle off) side of each overridden gear is machined on an ange and works together with a spring to slide into their natural position once overridden.

The only down side to an override tranny is that you can not let off the throttle without grabbing the clutch or the gear you are currently in will try to dis-engage and bend a shift fork. Reason being the shift drum has not rotated to the propper position for that shift fork to rest in.

The common override setup for a DS is the 1-2-3 and the 2-3-4-5 or other wise called a "two through five" or "two five".

You can let off the throttle normally on a 1-2-3 in 3rd, 4th, and 5th. But on the 2-5 you can only let off in 5th.

 

Thanks alot for the explanation.

 

does anyone offer a "duneable" override for the ds650? or are they all drag only?

 

i dont know about the ds650 to much in specfic but there are a couple companys that claim they have a duneable over but i would not buy a override unless all you do is drag

 

There is a Rekluse automatic clutch for the DS.

 

Duneable and override shouldnt be used in the same sentance...lol
It will work but not very well and not for long.