650G RPM / speed

[tkent02]

Can't remember, can't find the old posts. Anyone with a stock 650G know what RPM it's doing at what speed in fifth?

Trying to figure out which sprocket ratio I want in the 550/675... Trying to get the same in sixth as the 650 had in fifth. I remember the 650G was set up really well for highway speeds in fifth gear.

[Gorminrider]

that's harder than it sounds, you know..my tach says about 7000 rpm at 75mph per gps (the speedo reads too high on this bike) but if you trust a magazine article from Cycle World Ffeb 1982 it's supposed to be

60mph at 4667RPM (yes, that's about what I see =100kph in Canada) and 122mph at 9500 RPM

[Jedz123]

Can't remember, can't find the old posts. Anyone with a stock 650G know what RPM it's doing at what speed in fifth?

Trying to figure out which sprocket ratio I want in the 550/675... Trying to get the same in sixth as the 650 had in fifth. I remember the 650G was set up really well for highway speeds in fifth gear.

What Speed do you need? I'll break the G out tonight and let you know.

[tkent02]

Any speed, just pick one you can remember. I'll figure it out from there.

[Jedz123]

Roger!
Will do when I get home!

[Jedz123]

Tkent
5th gear
45MPH=3500RPM
55MPH=4250RPM

[tkent02]

Thanks, now off to see what mine does....

[tkent02]

I have something very close, but in fifth gear. 45mph = 3600, 55mph = 4350. Sixth gear is about 3250 and 4000.
Not quite what I expected.

[Jedz123]

Tkent what size rear are you running?

[tkent02]

The rear sprocket is the 550's stock 50, the front I just went from the stock 15 to a 16. This with the standard old 530 non o ring chain the 550s came with. I found an almost new chain off a 550L I parted out a while ago. I'm sure the chain won't last very long on one new sprocket and one slightly used one, but hopefully it will make it until the 700cc engine goes in this winter. I think just slightly taller would be right for that engine, the 16/50 combo sure seems to work well for this one.
Also it's an 18" rear wheel.

[Jedz123]

The rear sprocket is the 550's stock 50, the front I just went from the stock 15 to a 16. This with the standard old 530 non o ring chain the 550s came with. I found an almost new chain off a 550L I parted out a while ago. I'm sure the chain won't last very long on one new sprocket and one slightly used one, but hopefully it will make it until the 700cc engine goes in this winter. I think just slightly taller would be right for that engine, the 16/50 combo sure seems to work well for this one.
Also it's an 18" rear wheel.

I have a 17" on my G.

Now I see where your going with this... When you said 6th my mind went straight to, umm WTH is he talking about the G's never came with a 6th gear.

[tkent02]

Yeah, I just remembered I thought the 650G I had a few years ago had a really nice drive ratio for that engine. 5th would go plenty fast, yet would accelerate nicely without downshifting.
I have basically the same engine on a smaller lighter bike, so as thinking if I got it close I'd probably be happy with it.
I'm happy with it.