I don't know how you took your speed measurements, but the only one that is correct is 6th gear.

The speedometer drive is coming from the output shaft of the transmission (front sprocket). It just counts how many times that shaft turns. It doesn't care what sprockets you use or even if you have a rear wheel mounted. It always shows the same speed in relation to RPM for a given gear.

 

I agree.

You may want to repeat your test - because the data (in the lower gears only) does not agree with what I have experienced, and it does not agree with how the V is set up.

Then, you also may want to repeat the test - using a GPS as a speedometer, while riding on a flat, level road.

The 43 tooth sprocket will cause your actual (GPS) speed to be greater at any given RPM, in any gear. In other words, if you cruise at 5,000 RPM, you will arrive at your destination about 7% sooner - than if you had stock gearing. But your V speedometer will (falsely) tell you that your cruising speed did not change.

I updated my response in bold, for clarity.

 

I have same setup on a 2008 gen1,my speedo correction was similar to what you experienced, because the speed attand at rear wheel will be greater at the same RPM as before, you will have approximately 6 percent difference in odometer reading 100 miles traveled 94 miles indicated on odometer.YES I DID THIS WITH A GPS, AND SEVERAL HUNDRED MILES OF TESTING.

 

Sidebar here

Did you have to remove some link on your chain to reduce to 43t ?

Thank's

LOP

 

Sidebar: I mounted the same rear sprocket, 43T, and did not shorten the chain. New chain and new steel sprockets. I'm still undecided whether or not to keep the 43, I may go to 44, but 46 was too low for my riding. The V is a street bike that can handle most gravel roads. I know riders take the V everywhere but it's not a small KLR. I've figured out that my speedo after the change doesn't know how fast I'm going exactly. I think it's reading slower than I'm actually moving. The tires aren't exactly the stock size or profile either. I've noticed in a 90Kph zone where most traffic moves at 110+Kph my speedo now reads a bit over 100 and I'm keeping up. What a dumb way to measure speed....

 

Thanks for all the replies. More info:

That's my understanding, as well; indicated speeds are taken from the drive sprocket speed. Speedometer interprets speed from that figure, with 6 formulae (1/gear.) That's why I was surprised at the indicated results, which I listed in my OP.

What I mean by "indicated speeds" is simply what the speedo is stating. I repeatedly checked these figures, before and after the sprocket swap, so I'm confident that they are accurate. I'll do a GPS check, this weekend, but didn't do one with the 46t sprocket, so won't be able to compare, without swapping back, which I doubt I'll do.

I replaced the chain, along with the rear sprocket and yes, it is shorter than the prior chain.

Figures aside, I am satisfied with the results. Less shifting in traffic and highway cruising speeds seem to be in the less-buzzy 4,500rpm range.

PS. What "generation" is my 2012 650? Thanks.

 

PS. What "generation" is my 2012 650? Thanks.

You are Second Gen

If you want to have the speedo agreeing to your GPS get a Speedo DRD.

Mine is now spot on (but my odo (distance) is out).

 

OR - change your rear tire to a 150/70x17. W/ one on mine, my speedo reads VERY close to my GPS speed (100 on the GPS and 99 on the speedo, while the odo UNDER-READS by 1.7%)....