Tire pressure

[maxtog]

That's very impressive. Would love to see what you get out of the PR4 GTs

?  That is what I got out of the PR4 GT.

[Ghost Rider 2]

  I Have been wondering about dropping pressure on my 1400.  I also ride a 1800 Goldwing.  On all the wing forums everyone talks 40 and 42 pounds.  Been doing that for several years.  Older guy in my area kept saying that pressure I what wearing out tires.  Last set of 1800 tires I ran 36 front and 38 rear.  Normal rear tire I get 8 to 10 thousand. Front I will get 10 to 12 thousand.  This past set with lower pressure I pulled rear at 10,500 it was shot.  Front however went 15,000 and was just barely at wear bars. I did increase some and on this bike is commuting back and forth to work. so not much in the way of curves.

[sailor_chic]

To me, it seems that a lower pressure would create more friction. For me, I run mine at 43 psi

[maxtog]

Nothing will wear tires out faster than running them with lower-than-it-"should"-be pressures.  It allows the center to deform and the sidewalls to flex more.  The tire can't be held at the proper angle and the carcass can flex more.  It makes cornering harder and wears the center even more than typical.  It will also hurt fuel mileage.  To a degree, it MIGHT add some traction through additional friction, but if you plan on cornering hard it might backfire.

Over-inflation will also distort the tread some, will prevent the NEEDED flex to help hold the tire on the road, make the ride hard/uncomfortable, and won't necessarily extend the tire life much.

I think most on the forum agree that the factory-recommended 42psi is very near where it seems to wear the least and perform as expected.  42 is what I would recommend, unless you were riding 2 heavy-people with full luggage and wanted to add a few PSI to compensate (in which case you also probably need to adjust the preload and also adjust the headlight aim).

Besides, 42 is the answer to the ultimate question!  https://en.wikipedia.org/wiki/Phrases_from_The_Hitchhiker%27s_Guide_to_the_Galaxy#Answer_to_the_Ultimate_Question_of_Life.2C_the_Universe.2C_and_Everything_.2842.29

[B.D.F.]

Me too, and I think everyone else who has tried 42 PSI vs. lower tire pressures.

This usually stirs some kind of strange, Internet argument about the tire carcass having some stiffness but anyway.... tire pressure controls the tire contact area and it also controls, to a large degree (no pun intended) the friction of the tire and how it heats up. The C-14 is a big, heavy bike and by increasing the tire pressure above what is wanted or desired in much lighter sport bikes that use the same tire size, it reduces the contact patch area but also helps keep the tire cooler. For better or worse, a C-14 simply will not keep up with, say, a liter- bike using the same size tires. Sport bike tires and lower pressures work fine on a C-14 but not for long and it wipes out the tires and in the end, will not allow it to behave as a sport bike anyway.

Bringing the tires up to, let us call it 'normal pressure' for this bike, seems to work best overall. There is some 'grippiness' to be had by lowering the tire pressure but it is at the cost of fuel economy, overall handling feel, at least IMO, and certainly tire life. Some people have tried bona fide sport bike rubber on the C-14 with posted results of excellent handling for very few miles and extremely poor tire life.

42 PSI has worked best for me on my C-14. That is cold, and may register up to 44 PSI on the TPS display, after the tire is up to temp. (and the TPS sensors are temp. compensated- go figure).

Brian

Edited to use correct words. Long ago, people were taught to read, write and spell. Then came computers and lots of us (I am pointman on this!) gave up entirely on spelling and just use a spell check to correct spelling. The result is that instead of miss- spelling words, we have the machine simply use the wrong words in place of our perhaps correct but misspelled words.

To me, it seems that a lower pressure would create more friction. For me, I run mine at 43 psi

[maxtog]

For better or worse, a C-14 simply will not keep up with, say, a liter- bike using the same size tires.

Just a clarification based on my understanding/research.  When it comes to hard cornering, most liter bikes will likely win.  As far as straight acceleration and power,  most liter bikes can't keep up the C-14.  Take for example, the brand new (2017) Ninja 1000 sports bike- it posts about 10.6 to 10.92 1/4 mile times (and that was faster than the other bikes in its class which is was tested, and lightest too at 524 pounds).  The [stock/unflashed] C-14, on the other hand,  regularly posts sub 10.6 1/4 mile times.  The C14 is pretty evenly matched to most street/sport liter bikes on the straight or moderate cornering.  It's power and usable torque can usually make up for its feature-and-comfort-packed weight in most (but not all) situations.   Jump to super-sport liter bikes like the Kawasaki ZX-10R, Yamaha R1, or BMW S1000R and bets are off     Not exactly sure how tire sizes would change things all that much, as long as they are matched properly to the weight of the bike.

[B.D.F.]

What I was trying to convey was that while a C-14 will corner harder with lower tire pressures, it is really hard on the tires and IMO compromises the overall performance of the bike, which includes decent tire life and fuel economy. I think the gain in performance will be small compared to the losses. And my referencing a liter sport bike was to make the point that if one really wants performance, it is readily available at the local motorcycle store and used motorcycle markets without trying to squeeze performance out of a 700 lb. sport tourer and suffering the resulting downsides.

It seems that a lot of others think this way regarding the C-14, specifically regarding tire inflation vs. performance. Or at least it seems so to me based on ten years of listening to and reading about what others are interested in regarding C-14 use. And in turn I would steer others asking about tire pressure toward 42 or so PSI inflation as the best overall way to get the most out of both the bike and the tires.

That said, there is nothing wrong with running with lower pressure in the tires but it seems that most people do not want what that will result in, and are not particularly concerned about the small loss, and then only if pushed hard, in the bikes' performance.

Brian

Just a clarification based on my understanding/research.  When it comes to hard cornering, most liter bikes will likely win.  As far as straight acceleration and power,  most liter bikes can't keep up the C-14.  Take for example, the brand new (2017) Ninja 1000 sports bike- it posts about 10.6 to 10.92 1/4 mile times (and that was faster than the other bikes in its class which is was tested, and lightest too at 524 pounds).  The [stock/unflashed] C-14, on the other hand,  regularly posts sub 10.6 1/4 mile times.  The C14 is pretty evenly matched to most street/sport liter bikes on the straight or moderate cornering.  It's power and usable torque can usually make up for its feature-and-comfort-packed weight in most (but not all) situations.   Jump to super-sport liter bikes like the Kawasaki ZX-10R, Yamaha R1, or BMW S1000R and bets are off     Not exactly sure how tire sizes would change things all that much, as long as they are matched properly to the weight of the bike.

[oldnslo]

Just a clarification based on my understanding/research.  When it comes to hard cornering, most liter bikes will likely win.  As far as straight acceleration and power,  most liter bikes can't keep up the C-14.  Take for example, the brand new (2017) Ninja 1000 sports bike- it posts about 10.6 to 10.92 1/4 mile times (and that was faster than the other bikes in its class which is was tested, and lightest too at 524 pounds).  The [stock/unflashed] C-14, on the other hand,  regularly posts sub 10.6 1/4 mile times.  The C14 is pretty evenly matched to most street/sport liter bikes on the straight or moderate cornering.  It's power and usable torque can usually make up for its feature-and-comfort-packed weight in most (but not all) situations.   Jump to super-sport liter bikes like the Kawasaki ZX-10R, Yamaha R1, or BMW S1000R and bets are off     Not exactly sure how tire sizes would change things all that much, as long as they are matched properly to the weight of the bike.

my 09 c14 did a9.98 @141 mph in a quarter, oh yeah , i had a little help with a little blue bottle with NOS  on the lable.it was somewhat scarey when the front wheel kept coming up in 3rd gear.  took the nos off and never did it again...

[maxtog]

i had a little help with a little blue bottle with NOS

Cheater!!   

[Tree]

BUMP

I bumped this post in order to update the mileage.  I have over 12,000 miles on this set of Angels and they are just about finished.  Very happy with them and will replace them with the same.

I'm still considering a trip to the Dark Side but I'm too much of a chicken**** to make the move.  Maybe after the next set of Angel GT-A's wear out...  Maybe.

[B.D.F.]

I assume you mean car tires? Yep, those work to greatly increase tire mileage.

Still, I think it was really only a big advantage in the olden days when motorcycle tires would only last 2,000 to 3,000 miles. People resorted to car tires just to be able to make one trip, say, across the country and back, on one set of tires. Today's tires offer much, much better life and so a lot of the car tire advantage is gone, at least IMO.

Not saying there is anything wrong with trying out a car tire on a bike, I have no opinion on that other than certainly it works because people actually do it. Just reflecting that the original push to use them is pretty much gone.

Brian

BUMP

I bumped this post in order to update the mileage.  I have over 12,000 miles on this set of Angels and they are just about finished.  Very happy with them and will replace them with the same.

I'm still considering a trip to the Dark Side but I'm too much of a chicken**** to make the move.  Maybe after the next set of Angel GT-A's wear out...  Maybe.

[maxtog]

I assume you mean car tires? Yep, those work to greatly increase tire mileage.

On the rear only, however.   My experience is that the fronts only last a little longer than the rears (MT).

And with other issues (CT), of course.

[B.D.F.]

In the olden' days, the ultimate mileage trick was to mount a rear tire on the front wheel, then a car tire on the rear wheel for some truly long distance tires.

Again, while a CT on the rear will last much longer than most motorcycle tires, and they are less expensive, I still believe a great deal of the attraction of doing this has been eliminated by modern motorcycle tires, specifically sport- touring and just touring tires yielding a long enough life- span to make them practical for any and all motorcycle use. Even hard- core IBA riders are hard- pressed to find sanctioned rides of any extreme that can still not be finished with one set of motorcycle tires.

Brian

On the rear only, however.   My experience is that the fronts only last a little longer than the rears (MT).

And with other issues (CT), of course.

[gPink]

You had to mount the rear tire on the front backwards didn't you?

[B.D.F.]

Yeah, I think that is how it was 'normally' done.... such as that was ever normal. And I never did it myself- I never rode a bike far enough in one shot to have the problem until the C-14, and by that time the tires were more than up to anything I could manage to get the bike to do, mileage- wise.

But on a side note, I do find the whole car tire on a motorcycle thing very interesting. First because it works at all, and secondly because it seems to work pretty well. Now I am not suggesting that people do it, and have no interest in doing it myself (though I would take something like a C-14 for a ride with a C.T. on it if the opportunity presented itself- I am always curious about things such as this) but let's face it, there are too many people doing it successfully to believe anything other than it works at least reasonably well. Sure it may be less- safe but again, it works and it sure looks like it should not given those almost square profiles. And to be honest, given two bad choices like riding a bike with a good C.T. and a bald, 'cord showing' M.T., I would choose the C.T.

Brian

You had to mount the rear tire on the front backwards didn't you?