#of gears in xj700? 5th gear is 2500rpms at 35mph...

First of all, is an 85' 700 airhead a 5spd or 6 spd? and Is it normal that that at 35 mph in 5th gear that the rims are at about 2000-2500? I feel like if I get on the freeway ill be cruising at 65 and the bike will be revved to 6 grand..

 

The XJ's REV !! It's a good feeling.

But only the 550's and the later 600's chain-drive bikes (and the early 400-4's) were 6 speed (I think??)

Also the speedo's and tachs weren't "PERFECT" so some discrepancies can be blamed on inaccuracies.

The actual size of your front and rear tire matter, as well. New or worn??

In 4th gear, 60 should show about 6000 ( on my Seca 750 )

 

Actually, if 35mph in 5th is 2500 rpm, that's 14 mph per 1000 rpm, so 6000 rpm is 84 mph, . 6000 rpm just starting peak torque.

Different 5-speed Yamaha's do have different gear ratios, maxims typically spin faster so the torque comes on at lower speeds.

Time, my 750 Seca does 10 mph per 1000 rpm in 3rd. So it's doing 3000 rpm at 30 mph (maybe slightly less). 4th is faster mph for the same rpm (I don't know the exact number) and 5th I "know" is 14 mph per 1000 rpm (it's how I measure my speed above 85...when I used to do that :roll: ...doing math involving 7's in your head while going over 85 never felt quite "safe")

 

The "official Cruising RPM" per Yamaha is 5000.

The XJ series will happily run all day at 5000, 6000, 7000 RPM. The motor isn't barely even running the charging system at 2500 RPM.

In traffic, I pretty much keep 4K minimum on the tach all the time.

You just need to get used to spinning the motor. Notice the redline?

 

This isn't an old V8 with coke bottle size cylinders, its a .4 - 1.1 Liter four cylinder with very precise tolerances.
Smaller engines spin faster for the same reasons water droplets are always the same size. The tensile strength of steel remains constant, and because the stroke of a motorcycle engine is so much shorter than a large car engine, the piston speeds are lower. Even the bearings are smaller circumference which means they spin slower at a given rpm.

5000 rpm does as much wear on your xj as 2000-3000rpm would to a car engine.

 

Wow, and I was shifting below 3000.. My Mustang is actually my DD right now so, you guys are right lol, its against my nature. Im not used to it. Are there any effects in gas mialage when cruising saaayyy at 35 mph in 5th(2500rpms) vs. 3rd gear(5000rpms)?

 

Don't cruise below 3000 rpm. If you load up the engine under 3000 rpm, you're really lugging it. 3000-4000 is fine for just puttering around, but if you really need to get out of a bad situation fast (i.e. you need a usable amount of torque) be prepared to downshift, maybe even twice, and get the revs over 5000.

Gun the throttle at 3000 and you'll slooooowly pull away, gun the throttle at 6000, and you'll notice the difference.