gs650 vs 850 final drive question

[Guest]

I searched but couldn't find any info. Does anyone know what the final drive ratios are for a 650 and 850 shaft drive? Or if they can be swapped? I'm looking to lower the cruising rpm on my 650. Thanks for any input.

[koolaid_kid]

Must
resist
chain
versus
shaft
comment...

[Nessism]

Those rear ends are not interchangeable.

[Steve]

Must
resist
chain
versus
shaft
comment...

OK, Kid, I'll have to goad you a bit.

What size drive chain are you using on the TransAm?

And what sprockets on the front and rear?

[/hijack]

.

[Steve]

Now let's answer your question:

Does anyone know what the final drive ratios are for a 650 and 850 shaft drive?

Here are the ratios in the various drive trains:

......... Primary .... Secondary ................. Final
Bike .. Reduction .. Reduction .. 5th gear .. Drive
650 ... 1.775 ........ 0.941 ....... 1.000 ..... 3.09
850 ... 1.775 ........ 1.062 ....... 0.961 ..... 3.09
1000 ... 1.775 ....... 0.941 ....... 0.961 ..... 3.09
1100 ... 1.775 ....... 0.941 ....... 0.923 ..... 2.91

If you bother to do the math, you might see that you can save a few hundred RPM at highway speeds, but, as already noted, the final drives from the larger bikes will not bolt onto the 650.

The only other way to "lower the cruising rpm" is to not twist the right grip quite so much.

.

[salty_monk]

Or find a higher profile tyre... or a bigger diameter wheel that will fit (I think it's 17" already so prob not an easy task)

[67camaro]

Thats pretty much what I figured. Can't fit a taller rear tire on the bike. Thanks for the info.

[Redman]

I searched but couldn't find any info. Does anyone know what the final drive ratios are for a 650 and 850 shaft drive? Or if they can be swapped? I'm looking to lower the cruising rpm on my 650. Thanks for any input.

I understand (mostly from comments here on GSR) that the 650 is probably the size of GS with the least interchangeable parts with other sizes of GSes.

.

[Larry D]

I never understood why folks want to lower the RPM.....these bikes love to rev, they want to rev, revving is what they do, take 'em up to redline and have some fun......

Sure, it may save a few cents in gas, but, you aren't going to blow it up by cruising at 70mph down the highway.

[Steve]

I never understood why folks want to lower the RPM.....these bikes love to rev, they want to rev, revving is what they do, take 'em up to redline and have some fun......

Sure, it may save a few cents in gas, but, you aren't going to blow it up by cruising at 70mph down the highway.

It's not unique in the GS community, either.

newer GoldWing owners compalin that the bike is turning about 3100 RPM at 70 MPH.

My van only turns about 2100 RPM at 70 MPH. That's why the bikes sound so "busy" when they are singing at 5000+ RPM at 70 MPH.

.

[koolaid_kid]

I added a tooth to my front sprocket last year (15->16) and I love it. Not for the fuel economy, not to keep from revving too high, but because at highway speed it put me in the range where the harmonics made my bars buzz and put my hands to sleep. I wanted to add a bar snake or bar end weights, but my bars are solid and neither was feasible. If I ever go to another bar I will put the sprocket back to stock so I can regain all that low end torque at take off I surrendered.