RPM and Speed

Wanderer · Apr 12, 2007

Over Easter weekend I left the 'Springs and rode overnight to Phoenix, yeah it was all slab, and it sucked, but I was able to ride pretty much any speed I felt like. I-40 is curiously devoid of the Po-Po at 2am. I found myself creeping up to speeds over the ton. In fact "in theory" :lol: I spent more than a few lonely minutes at an indicated 125. This put the tach at over 6k RPM! I felt more than a little apprehension regarding leaving my engine running at nearly 3/4 redline for, what would have been, had I done it,

an extended period and backed off for speeds in the double digits. Any harm in this? The bike sounded great, my MPG went to ****, but it left me with this burning question...

Is 100+ too much for the FJR to cruise at for lets say a full tank of gas??

Bearly Flying · Apr 12, 2007

Uhmm... Nobody on this forum will be able to answer that,,,, cause we all drive the speed limit.......

Ignacio · Apr 12, 2007

I might...since I have a private track in the state of Nevada

It's fine.

The bike will cruise along happily for many, many hours and many, many tanks of gas at a buck twenty to a buck thirty five. Add some 5 or 10 minute stretches at FJRmax and the bike is a solid. Several others on the board can attest to the stoutness and longevity of the bike at elevated speeds as well...and I'm talking about Gen I bikes with shorter gearing.

As you said mileage suffers.....seriously. Seeing the low fuel light come on at 160 is a trip guaranteed to put a smirk on your face and happily flip the handle on one's auxiliary fuel cell.

And I would say the rear tire tends to wear out more quickly. I noticed I only got 4500 miles out of that particular tire.

Individual results will vary. ...and never do this on a public road....that would be crazy

A shot from my private track somewhere near Austin.

E1Allen · Apr 12, 2007

triple digit issues? what issues?

BeeLine · Apr 12, 2007

I would watch the temp gauge and vary the throttle once in a while.

SkooterG · Apr 12, 2007

No issue whatsoever.

At that same test track Iggy is talking about I completely FLOGGED my FJR for 24 hours. Without going into specifics, I will say I was above your 125mph for most of the day. My 04 had about 75,000 miles on it at the time and performed flawlessly.

madmike2 · Apr 12, 2007

RPM and Speed, '6th gear'-like topic

Soooo, you want an overdrive for your overdrive?

Me am habin' trubble to unnerstan' whut yewer sayin' en yer titel tew the post. Jis' whut wood geer 6 be heppin' whin thuh 5th geer is a consarn uberdrive now? Eye 'spose yew kood en-joy usin' thet dang-it-all left foot thingy moor tymes tuh be gettin' tew thuh overdrive geer.

Eye s'pose thet's wye this is en thuh NEPRT. Heh-heh-heh-heh-heh. :lol:

PapaUtah · Apr 13, 2007

Go down to your local dealer with about $600 and ask him to order part number 4XY-46101-00-00, REAR AXLE GEAR CASE ASSY. When it arrives bring it home and remove your back tire and rear axle gear case assembly. Install this new part and reinstall your rear wheel. You will now have reduced your rpms by 10% across the board. Launch will require a little more clutch touch but after that you will be good to go. 3900rpm will now have you sailing across the pavement at about 80. 70mph requires only a leisurely 3555rpm from the FJR.

charismaticmegafauna · Apr 13, 2007

FJR @ continuous high speed? -- no worries, mate. No need to worry about stock gearing, either. Contrary to popular belief; taller gearing (less rpm) doesn't, necessarily, lessen the load on the engine -- in fact, too high a load at too low of revs is more work for the engine.

In the 'old days': Honda sold motorcycles in the '60s saying, "Our bikes are designed to be operated at a continuous 75% of maximum." If you ever witnessed the normal operation of either a CB160 or CL72/77, you'd know that was true.

In the words of Mr. Soichiro Honda: "Revs are free."

turbodave_98 · Apr 13, 2007

MNFJR05 said:
Go down to your local dealer with about $600 and ask him to order part number 4XY-46101-00-00, REAR AXLE GEAR CASE ASSY. When it arrives bring it home and remove your back tire and rear axle gear case assembly. Install this new part and reinstall your rear wheel. You will now have reduced your rpms by 10% across the board. Launch will require a little more clutch touch but after that you will be good to go. 3900rpm will now have you sailing across the pavement at about 80. 70mph requires only a leisurely 3555rpm from the FJR.

In model name terms, what rear axle gear cage assembly are you talking about?? Sounds like the "pumpkin" change I did on my Royal Star by putting in a V-Max pumpkin. Really would like to know!!

SkooterG · Apr 13, 2007

turbodave_98 said:
In model name terms, what rear axle gear cage assembly are you talking about?? Sounds like the "pumpkin" change I did on my Royal Star by putting in a V-Max pumpkin. Really would like to know!!

I am guessing it's the old Venture. Could be the V-Max however.

PapaUtah · Apr 13, 2007

It's the gear case assembly for the Royal Star Venture, which is really the 3rd Gen Venture. You might be able to get into a bike boneyard and get an old Venture Royale unit(you must get the 86'-'93 model if going after the older VR). They are all the same. Difference between the FJR/VMax and the Venture is one tooth on the pinion. Results in 3.33:1 gearing on the Venture and 3.66:1 gearing on the FJR/VMax.

otrfjr · Apr 14, 2007

Lots o' Max owners have done the final gear swap to lower cruising rpms with no ill effect. Not sure about acceleration or mpg (but since you can do a holeshot in 2nd gear, I doubt power would be the issue).

As for the original post: it's my naive understanding that internal combustion engines--well designed & well manufactured--prefer to run at something approaching capacity. Not that I'm advocating full throttle operation all the time anywhere. But if everything is running at equilibrium, what can happen? In terms of spacetime, you're covering the same distance in less time, so internal wear is the same. If it's a constant. Where's Stephen Hawking?

Here's a good one: I saw Hawking speak & one of the most memorable things he said was, "When I assumed the Lucasion Chair of Mathematics...it didn't have wheels."

MNFJR05 said:
It's the gear case assembly for the Royal Star Venture, which is really the 3rd Gen Venture. You might be able to get into a bike boneyard and get an old Venture Royale unit(you must get the 86'-'93 model if going after the older VR). They are all the same. Difference between the FJR/VMax and the Venture is one tooth on the pinion. Results in 3.33:1 gearing on the Venture and 3.66:1 gearing on the FJR/VMax.

timalan · Apr 14, 2007

I'll pipe in shortly on this.

Going from the Concours to the Feejur....

Somewhere between third and fourth on the FJR is the same as sixth on the conc.

So gear ratio????The Fjr is Lower engine speed than the concours at the same speed and much much much smoother.

My wife thinks scarrrry smooth. Speed is easy on the FJR

I find my self 7/8 of the way home on a 30 mile commute sometimes still in third goin 80 in smooth comfort. there is absolutely no need for taller gearing.

JMHO

Timalan

Wanderer · Apr 30, 2007

This was in no way intended to be a "my bike needs a 6th gear" whine.

Think of it more as a 'I'm a skirt and don't want to damamge my precious motor by flogging the dog-piss out of it because I have a heavy right wrist" whine.

Thanks to all who saw this for what it was and informed me that I'm not stressing the bike by holding it at 6-7k revs on the road.

mcatrophy · May 1, 2007

You can play theoretical games with your gearing here.

Scythian · May 8, 2007

I spent more than a few lonely minutes at an indicated 125. This put the tach at over 6k RPM! I felt more than a little apprehension regarding leaving my engine running at nearly 3/4 redline for, what would have been, had I done it, an extended period and backed off for speeds in the double digits. Any harm in this?

No. It'll do that all day; day after day. Hell, it prefers to run between 4.5K and 8K! It's the low-end tooling around that carbons it up. Jestal gave some great insight into this kinda thing on a previous thread.

These 'new' engines are just incredible--compared to even 20 years ago. It's more like a modern aircraft engine than anything....

FJRMGM · May 10, 2007

I have an '04 Ford Focus SVT and it actually gets BETTER gas mileage at 75 mph than at 65 cause it seems to like the rpms at 75 mph better so I concur about running at higher rpms.

Flyguy · May 12, 2007

FJRmgm wrote:

I have an '04 Ford Focus SVT and it actually gets BETTER gas mileage at 75 mph than at 65 cause it seems to like the rpms at 75 mph better so I concur about running at higher rpms.

Didn't you know that EVERYTHING runs better at 75 than 65 - in Texas. (remove hat and place over heart)

That law was passed years ago!

RPM and Speed

Help Support Yamaha FJR Motorcycle Forum:

Well-known member

Well-known member

Intramural Culture Warrior

Youngster

Well-known member

Purveyor of Crooked Facts

Shtirrenuppenmeister

Well-known member

Well-known member

TurboDave_98

Purveyor of Crooked Facts

Well-known member

Don&#39;t tell Mom

Well-known member

Well-known member

Privileged to ride a 2018 FJR1300AS

Well-known member

FJRMGM

Well-known member

Similar threads

Join the conversation!

Join today and get all the highlights of this community direct to your inbox. It's FREE!

Don't tell Mom