Just switched back to dirt and used the SM speedo drive.

[MuddDawg]

I bought one form Denroll when he ordered the SM Speedo Gears. Running D606s, Stock S gearing 15/44, and the SM speedo. As Per my GPS the Speedo is 1 MPH fast. I only tested up to 30. 25 MPH speed limit in my neighborhood. For those that care or actually dualsport their 400S's. ?

[DRZBigB]

What exactly is that part - the small metal piece ON THE HUB??

So - you're saying the "SM" speedo drive - it fixes the "S" speedo too??

If that's the case - shouldn't the "SM" speedo drive be even smaller?

We "S" guys should all install it then!!!!

[fartsmeller]

What you talkin' 'bout willis?

in other words please explain for us noobs Is this something I can use to correct my speedo when I change the gearing on my SM?

[MuddDawg]

Sorry guys I lost track of this thread and just saw it. So you take off your front wheel/rim and on the right side of the bike is a black speedometer drive that the speedometer cable plugs into(it is held in by a Phillips head screw.) That black piece of plastic has the gears in it that run the speedometer. I got a factory SM version of that, and it brought my error down to 10% from 20% with my 17s. The speedometer and odometer is still off, but not as bad. Now if I leave this SM speedometer drive on when I put the dirt gear back on it is about 1% off. I hope this helps. Would I do this mod (if you can call it that) again? probably not. I could use the $40-$50 for something else. I have a GPS and a Tach, so I usually watch those. With my 17's in 5 gear I add 300 rpm = Speed. 6700 RPM plus 300 RPM = 70 MPH.

[Fred_Bear]

let me get this straight

the stock SM speedo drive corrects the speedo on the dirt model to within 1% right?

[Fred_Bear]

MuddDawg?

[bayoubikebruiser]

It sounds like he's saying that the +/-8mph error factor on the "S" model speedo can be narrowed to only a +/-1mph error factor by swapping a SuperMoto speedo drive gear in place of the original "S" model's speedo drive gear.

As the wheel/tire diameters are pretty close between K, E and S models, it should have the same effect on an E or K.

[MuddDawg]

Yes, and it should be the same on the E/Ks, but I have not tested that. I have been getting bad head shake @ 70ish, and I don't remember if the speedometer is accurate up to that point.

[Linco]

The "S" speedo with 17's is 9mph off, when it reads 30mph you are going 21mph. I highy doubt that the SM speedo drive is only 1mph off the other way.

[anathema]

He is saying that using the SM speedo with the bigger 21 inch dirt wheel corrects the indicated speed down to 1%

[Neil Claydon]

Just a thought here, cause it's late and my maths is a bit slow.

1/ How much smaller is the rolling diameter of a 17" compared to a 21", as %.

2/ What is the difference between a Kilometre and a Mile as a %.

If the two %'s are similar, could you use an in-line Kilometre to mile converter in the speedo cable to correct the inaccuracy caused by the 17's ?

Neil.

PS. Never looked, but I would assume that there is a converter from Miles to Kilometres as well.

[Linco]

He is saying that using the SM speedo with the bigger 21 inch dirt wheel corrects the indicated speed down to 1%

How can the speedo drive from the 17 inch wheel correct anything?? Its calibrated for a 17 inch wheel, Its a gear that spins set up for a 17 inch circumference. If the 21 inch wheel is on it theoretically would be 9mph to fast!!

I checked muddawgs post again, I beleive he was saying that with his 17's on he was still not accurate, this means that its a waste of money to put the speedo drive from the DRZ400SM on the DRZ400S with 17"s on. The part is still on BO here in the states anyway!!!

[anathema]

Sort of linco but what he is saying is that because the SM speedo gear is calibrated for a faster spinning wheel (so lowers indicated speed)..and since his speedo reads high all the time...the combination of SM speedo gear and S tires makes the stock speedo within 1%.

[MuddDawg]

Yea, what he said.

[Fred_Bear]

Yea, what he said.

I thought so. It would be nice to be within 1% instead of 10% I wish that it was dead on!!

[Linco]

I live with mine at 9mph off when I'm running my 17's. When trailtech comes out with a backlit unit I will junk my stock speedo.

[MuddDawg]

I wish mine was dead on as well. My 400s handle bars are getting quite cluttered with hand guards, GPS, Tach and all the other S model stuff. My problem now is remembering what I am running. Dirt set up or SM, Then what speedo drive am I running. So... am I 10 % off, 20% off or 1% off. My little brain just cant handle it. The GPS is the way to go, but... if you get pulled over by Johnny Law you don't have much of an excuse.

[jsb223]

If the SM plastic thingy will fix a S speedo, will the odometer then be affected and show too many miles?

[DaveI]

Resurrecting this old post...

So what was said is that ordering the SM speedo gear and installing it on a DRZ"S" with normal size wheels will lower the DRZ"S" speedo error down to about plus or minus 1%. Who has done this? Can you verify and please advise what part number to order? I still haven't made up my mind to go with the Trailtech as I want to retain the indicator lights. Thanks. ?

[HooterHonker]

If the SM plastic thingy will fix a S speedo, will the odometer then be affected and show too many miles?

I believe it would be the other way around, it would show too few miles. Remember, you can calibrate the trip meter on the instrument cluster to make it accurate. The SM hub is going to spin fewer times per mile than one from an s on the same tire.

HH