• 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.

Which tires for me and my 1978 GS750?

  • Thread starter Thread starter titanfus
  • Start date Start date
T

titanfus

Guest
First, let me say that I am a motorcycle newbie, so please don't leave out any detail in your replies because you think I may be offended.

I have a 1978 GS750 that I just revived from the dead and both the front and rear tires definitely need replacing.

I ride very conservatively and defensively. I do not need performance or speed tires. I need safe and comfortable tires that are suited for commuting and weekend cruising short distances.

Here is what it says on the bike for tire sizes:

Front: | Rear
3.25H19-4PR | 4.00H18-4PR
19x1.85RIM @ 25PSI | 18x2.15RIM @ 32PSI

Here is what is on the bike:

Front: | Rear
Nankang | Dunlop K391S
3.50H19-4PR | 130/90 V16
Max PSI: 40 | Max PSI: 42


Ok, here are my questions:

  1. Can you give me a summary of what all of these numbers mean? I have googled many times and cannot find a definitive list.
  2. I have what appear to be stock, spoked rims will I need tubed tires?
  3. What type/brand/size do you recommend for my purposes? I would like to emphasize stability and safety over price and anything else.
Thanks in advance
 
Look like you need a 100/90/19 front, 120/90/18 rear (100mm is the width, 90 is the aspect ratio, 19" is the rim size)

You can use tubeless tires with tubes. (the only street tires that fit will be tubeless)

As far as the brand and model, you'll get an endorsement for every one if you watch this thread long enough. :-D
(I like Dunlops, the model depends on what I'm using the bike for)
 
Last edited:
Good!

Good!

You happen to have the perfect attitude because I think you realize that your tires are "where the rubber meets the road" on a motorcycle.....it's amazing how some people overlook that fact. As the others have said, get a good tire in the right size, have it mounted properly, check for problems and check air pressure often...and you'll do just fine.!! OH,.....and, be careful!!!:-D
 
Thanks for the quick reply and the clarification on the numbers.

I just thought of another question:

There is a PSI rating that is on the bike itself (Front: 25, Rear: 32).

I have always put in the maximum PSI when filling my car tires, should I match the value on the bike? or on the tire?

Should I get a tire that matches that PSI? or is it OK to inflate a tire with a max PSI of 40 PSI to only 25 as it says on the label on the bike?

Thanks again,

-Paul
 
I have the same bike and am in the same position with tires. I shoped around and bike bandit has a set of tires that have gotten very good reviews on this site. They are a no name brand Ching something (you'll know what brand i am talking about when you see them) I got both front and rear tire delivered for $97. They are rated for the driving you are looking for. Good luck.

P.S. if anyone knows what tires i am talking about if you could help me out with the name. I'd run out and look but their in the locked shed.
 
I just happened to be on bikebandit.com when you replied. :-)

Like I said, I am more interested in stability/safety than price, so if a little more money will provide this then I'd like to know if this is the case.

On the other hand, since I do not need high-performance tires maybe these are just fine and spending more is just throwing money away?

Anybody else have some thoughts on this?
 
titanfus said:
I just happened to be on bikebandit.com when you replied. :-)

Like I said, I am more interested in stability/safety than price, so if a little more money will provide this then I'd like to know if this is the case.

On the other hand, since I do not need high-performance tires maybe these are just fine and spending more is just throwing money away?

Anybody else have some thoughts on this?
Click to expand...

The hardest part is finding the correct sizes. You don't have a whole lot of choices with the narrow tires that fit on our bikes.
 
One bit of advice for you, don't listen to the knuckleheads that tell you to run the maximum pressure stamped on the tire. They'll tell you that because of today's construction you need to run higher pressure, hogwash. Start out at what the bike specs call for and go from there. The maximum pressure stamped on the tire also has a carrying capacity that goes along with that pressure. In most cases you aren't carrying anywhere near that weight.

If you really want to know you are running the right pressure for your needs check the cold pressure before you start riding. Then after about 10 minutes of constant riding recheck the pressure. Ideally you should now have 3 lbs more pressure than when the tire was cold. Less and the tire is staying too cold. Like this you have less grip and will run the center out of the tire quicker than you should. If you have more than a 3 lb gain you are running too little air. The tire is going to run hotter than it should and wear out quicker.
 
Billy Ricks said:
Then after about 10 minutes of constant riding recheck the pressure. Ideally you should now have 3 lbs more pressure than when the tire was cold. Less and the tire is staying too cold. Like this you have less grip and will run the center out of the tire quicker than you should. If you have more than a 3 lb gain you are running too little air. The tire is going to run hotter than it should and wear out quicker.
Click to expand...

I've never heard this before and it sounds like great advice. Is this a well known *trick* for the racers or am I just an ignorant dude?

Josh
 
Billy Ricks said:
If you really want to know you are running the right pressure for your needs check the cold pressure before you start riding. Then after about 10 minutes of constant riding recheck the pressure. Ideally you should now have 3 lbs more pressure than when the tire was cold. Less and the tire is staying too cold... If you have more than a 3 lb gain you are running too little air. The tire is going to run hotter than it should and wear out quicker.
Click to expand...

I heard something similar to this at a seminar that was presented at the Aspencade Rally in Ruidoso, NM back in 1981. What was presented to us was 3psi for the front, 5psi for the rear. On the GoldWing board that I visit frequently, their rule of thumb is 10%.

Titanfus,
Tires for bikes, cars, trucks, whatever have a maximum inflation pressure, as you have noted. They also have a maximum weight. In order to carry that weight, they need to be inflated to max pressure. If you are not carrying maximum weight on the tire, there is no need to run max pressure.

Car tires come in many more sizes than bike tires, and each size has a different weight rating. If the actual weight of the car is near the maximum load of the tire, it makes sense to run max pressure. I have always run more then the car manufacturer suggests, as they tend to go for maximum comfort. Since the edges of the tires wear out sooner on my cars, I run more pressure to help balance the wear.


.
 
You must log in or register to reply here.
Back
Top