Final drive tools

[SkooterG]

Couldn't you get close to the same results by changing tire size?

Just wondering, Dave

Or..... the ultimate high speed tourer: Gen II+ with it's lower gear ratio middle gears, Venture FD gearing in the pumpkin, and a car tire installed!

 

[Rogue]

Couldn't you get close to the same results by changing tire size?

Just wondering, Dave

How much larger would you have to go to increase by 10% and how would that affect the handling/steering geometry?

 

[08FJR4ME]

Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
180/55-17 3.9in 12.4in 24.8in 77.9in 813 0.0%
190/55-17 4.1in 12.6in 25.2in 79.3in 799 1.7%

Well it looks like to be only a 1.7% decrease. How that relates to engine RPM's is another question.

 

[Kelvin]

Kelvin, what FD did you get from Ebay?
The Venture (RSV) Final Drive (FD) unit will not fit on your FJR (they do look similar).
What you need is the RSV GEAR-SET and those must be installed in your FJR FD case. And this is the Service that had been offered by the guy who passed last year (John Furbur @RMSportMax). He had the tools and expertise to make the swap, set the gear lash etc.
Regards,
Mr. BR

I am going with the FD that BugR so generously is gifting me. Gonna swap out the ring and pinion from that Venture FD into my FD. I don't know what year it is.

 

[Mr_Canoehead]

Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
180/55-17 3.9in 12.4in 24.8in 77.9in 813 0.0%
190/55-17 4.1in 12.6in 25.2in 79.3in 799 1.7%

Well it looks like to be only a 1.7% decrease. How that relates to engine RPM's is another question.

Revs/Mile should directly correlate to RPM's (and speedo error if it reads off the back wheel). I wonder how far off your revs can be between the front and rear before the ABS unit starts to get upset? I suspect the basic unit on my '06 wouldn't care but the newer bikes might act up if they have traction control. It's an issue on KTMs - when someone changes wheel sizes, you need to change the abs rings to compensate.

I know people have gone to 190s for a while. If you go much bigger, your centerstand probably won't lift the rear wheel off the ground. I raised my rear ride height with my Penske shock and found I couldn't go very far before the centerstand wasn't working.

 

[Mr. BR]

Mr_Canoehead,
Valid points for sure... fortunately, my '05 is non ABS so no issue there. I've run the 190/55 for years and yes, on the centerstand, the rear tire is now barely off the ground AND, I also have a Penske rear shock which is just a tiny bit longer than stock. Btw, on my '05, I did end up installing a "speedo-healer" to get my speedometer a bit more accurate after I installed the RSV geared FD unit.
Mr. BR