• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

curious thing happened after my chain swap

  • Thread starter Thread starter Boriqua
  • Start date Start date
B

Boriqua

Guest
I had a 16T front and 40T rear 630 chain and after the usual outstanding help I got here I went to a 18t front and 48t rear 530. The old chain was beat to death, was not an o ring chain and like most chains that are crapped out it would have tight spots when trying to adjust and then a big sloppy spot.

My new setup gives me a lower top speed but makes it a fair amount more perky. It of course raised the rpm at any given speed.

So I just went through my first tank of gas with my new chain set up and ..... I gained 3+ miles per gallon!?

I fully expected to lose some mileage since I am up on rpms throughout the ride but I went from a steady 40 miles per gallon over the last 4 or 5 tanks to 43.3 after the chain swap.. Im thrilled but ... what do you think happened.
 
Volumetric efficiency. Increased intake charge speed. Likely something along those lines. Lower engine speed doesn?t necessarily equal better mileage.
 
Maybe now you will understand and agree when we say (over and over again) "Let it SPIN". :encouragement:

.
 
All motors have what I call their happy place, as in rpm. I think you found it.
 
The old chain may have been absorbing more power.
Flapping around and noise is not free.
 
Did 80 miles yesterday at 75-80 mph and it really did feel in the zone.engine was just singing right. Very happy with the new gearing!
 
So I filled up today after my long highway jaunt from the post above and a few extra miles. Now considering it was singing along the highway at about 5000 rpm I was curious to check mileage.

45.25 MPG.

Now I never checked the mileage the last time I owned a GS 750 in the 70's but that is better than my last three bikes. I am assuming that is good MPG for this machine.

It certainly does seem to like to spin some!!
 
I get slightly over 40mpg on my shaft driven 850, and I have it a touch on the rich for jetting. I like mine that way. So 45 seems reasonable to me.
 
With the changed gearing your motor probably isn't labouring as much. An engine under load will consume more fuel than one that is coasting.
 
Most inline four cylinder bikes get there best fuel economy between 5-6 k rpm, they seem to burn the fuel more efficiently. The newer fuel injected models may differ some.A couple years ago I did a trip out to Colorado with a friend of mine, he was riding a HD ultra classic and got 51-52 mpg @ 65mph. I was riding my 05 FJR 1300 @65 mph I was only getting 39-41 mpg, but if We ran at speed up 75-80 I got 47-49 mpg and he got 35-40 mpg(. And started using oil) so the happy medium was to run at 65-70 and I just follow him in 4th gear and kept rpms up
 
Last edited:
Changed over to my summer oil about 300 miles back and thought it would really hurt my mileage since its 20w50 but I checked today and got 48mpg from the old girl on my last tank !! WOO HOOOOOOOO

It really does seem to enjoy a little more rev.
 
Spin to win!

Grip it and rip it!


Seriously, these engines LOVE to spin. They NEED to spin. If you don't wind your GS750 or GS850 to redline a couple of times per ride, you're missing out and making your engine sad. They hate putt-putting around like little old ladies or V-Twin pirates.

Once you get comfortable with RPM, the GS750/850 engine is one of the more entertaining powerplants ever created; that rush between 6,000 and 9,000 is downright addictive.


And personally, I think if you're worrying much about mileage on a motorcycle, you're doing it wrong. I pay some attention to mileage so I have a rough idea of when to fill up (you can't trust a GS gas gauge), but riding to maximize mileage is boring.


And yeah, I've never quite figured out how Harleys get such surprisingly good gas mileage. I guess the EFI is set up REALLY lean to pass emissions, and mileage efficiency is one side effect.
 
bwringer said:
Once you get comfortable with RPM, the GS750/850 engine is one of the more entertaining powerplants ever created; that rush between 6,000 and 9,000 is downright addictive.
Click to expand...

I agree with this wholeheartedly! When I'm cruising on my 750 Katana the RPMs are always in the 5000 and above range. And you're right - when you crack the throttle and the engine gets to around 6000, it's just hold on tight and enjoy the ride! My old GS650GL used to give me a little rush when it took off, but nothing like this! Perhaps my gas mileage suffers a bit because I ride at high RPMs, perhaps not, but it's well worth it regardless.
 
Last edited:
I would have been pleased to get 35 mpg. I didnt get the bike because I was thinking mileage but I am kind of a nerd about some things and I like to check the mileage to see how things I do to the bike affect the mileage and running. Getting that kind of mileage is just a bonus!

To think a year ago I couldnt get it to hold idle!

When I was young and had my 8v GS with original gearing I always rode at around 5000 rpm. I lived in NYC and I called it my escape RPM. At that RPM on my 750 if something came up I could crack the throttle and Whoosh! The brake isnt always the answer to an "Oh Sh*t" situation.

The gearing I got with this bike .. probably because of the long highways stints to get anywhere here .. was really tall and it cruised along at about 3600. Now that I changed the gearing some I have been riding in normal riding at about 4300 where it seems to be happiest cruising around town and man its a dream ... and its at about 5200 at full on AZ highway speed.

and

WHO CAN COMPLAIN ABOUT 48 MPG!!! woo hoo
 
You must log in or register to reply here.
Back
Top