The member photo gallery is now integrated and live!!  All user albums and pictures have been ported from old gallery.


To register send an e-mail to admin@bmwr65.org and provide your location and desired user name.

Author Topic: Innertube or Not?  (Read 1371 times)

Crossrodes

  • Guest
Innertube or Not?
« on: July 14, 2008, 04:28:19 PM »
I'm just in the process of changing my front tire (among other things) ....'79 R65 with 18" snowflake rim.  The tire I'm removing is a 90/90-18 Pirelli.  The new tire is a Bridgestone Battleaxe BT45...same size.  Both tires are tubeless.

I discovered an inner-tube inside the Pirelli as I was removing it.

I know there has been some discussion about whether inner-tubes are necessary or not on these wheels.  What are the thoughts out there.

Mike

Offline Bob_Roller

  • Global Moderator
  • Mt. Olympus Resident
  • *****
  • Posts: 9122
  • -7 hours GMT
Re: Innertube or Not?
« Reply #1 on: July 14, 2008, 04:35:09 PM »
The snowflake rims, are not designed for tubeless tire use.

I guess the tubeless tires have a larger bead area, as compared to a tubeless tire.

There are riders out there that use the tubeless tires without a tube, and don't seem to have any issues with it.

I personally would not use a tubeless tire on these rims.
'81 R65
'82 R65 LS
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!

Offline Justin B.

  • Administrator
  • Mt. Olympus Resident
  • *****
  • Posts: 5983
  • I love my Beemers
Re: Innertube or Not?
« Reply #2 on: July 14, 2008, 04:53:33 PM »
There is a difference, as Bob points out, in the bead area which technically makes them unsuitable (from a technical point of view) to run tubeless.  "Experts" are split on this and some say it's fine and others wring their hands and cringe.  If you do decide to run without tubes I have also read that (at least on the bigger bikes) some of the Snowflake rims suffer a porosity issue in the casting and don't hold air very well...
Justin B.

2004 BMW R1150RT
1981 R100RT - Summer bike, NEKKID!!!

crazy_dan

  • Guest
Re: Innertube or Not?
« Reply #3 on: July 14, 2008, 05:22:31 PM »
i've got all the service records for my bike, including bill of sale (wow!), and on all the tire change records, i've got a listing for a tube with the tire.  i figure if the bmw dealership is putting a tube in those tires, i'll spend another $10 and put a tube in too.
 [smiley=3stooges.gif]

Offline montmil

  • Mt. Olympus Resident
  • ****
  • Posts: 8371
Re: Innertube or Not?
« Reply #4 on: July 15, 2008, 07:04:26 AM »
...And if Ford Motor Co feels that Firestone tires are just fine for their Explorer models, who am I to argue? After all, they -Ford- are the "experts".   [smiley=2cents.gif]
Monte Miller
Denton, TEXAS
1978 BMW R100S
1981 BMW R65
1983 BMW R65
1995 Triumph Trophy
1986 VW Cabriolet

Jon_P

  • Guest
Re: Innertube or Not?
« Reply #5 on: July 15, 2008, 07:20:42 AM »
i have had blow out with tubes and with out tubes. i run tubes in everything even if the rim is supposed to be set up for running tubeless. the tubeless blow out almost killed me and my then wife. the shop who put the tire on also didnt put on the tire keeps which didnt help. so now i run tubes and if i get a flat it gets soft and not air the air out at 65mph blow out flat with the rear tire coming off the rim and wedged in the swing arm accident.

for the extra $10-15 i think it is worth it.

(isnt Ford and Firestone/Bridgestone family? think a son of Henry married a Firestone gal??? and that is why use those tires???)
« Last Edit: July 15, 2008, 07:22:38 AM by Jon_P »

Offline Justin B.

  • Administrator
  • Mt. Olympus Resident
  • *****
  • Posts: 5983
  • I love my Beemers
Re: Innertube or Not?
« Reply #6 on: July 15, 2008, 10:04:14 AM »
Jon, I have also heard the opposite from self proclaimed "experts" on another forum.  Their contention being that often a tube will rip and deflate instantly whereas a puncture in a tublerss setup will leak slowly.  I suppose it all depends on what type of tube.  In my experience a lot of the synthetic tubes don't hold up very well when holed compared to a natural rubber tube - but natural rubber tubes are getting harder to find and are several times heavier.  I think the last natural tubes I ordered were Pirelli, they are very thick, and weigh almost as much as the tire!  Well, maybe not that much but they are extremely hefty...
« Last Edit: July 15, 2008, 10:04:43 AM by admin »
Justin B.

2004 BMW R1150RT
1981 R100RT - Summer bike, NEKKID!!!

Offline nhmaf

  • Global Moderator
  • Mt. Olympus Resident
  • *****
  • Posts: 5156
  • Free at last, Free at last!
Re: Innertube or Not?
« Reply #7 on: July 15, 2008, 10:53:42 AM »
BMW designed those cast wheels to be used with tubes, so that is what I do.

Bridgestone/Firestone have had some quality issues, but one of the biggest factors in the Ford SUV debacle was that the idiots at
Ford decided that it was best to run the tires underinflated, as the softer tires would partially offset the stiffness of the truck-suspension
upon which the earlier explorers were based.   Mrs. Soccer Mom didn't want to have a harsh truck-like ride, and the quick/easy/cheap answer
at Ford was to state the tires should be run at 26-28 PSI.    I wonder how many motorcycle riders would be convinced if BMW told us that we
should be running our modern tires pressures at 26 PSI as they didn't want to do something to redesign their bike suspension system ?
26 PSI might have been OK to do in the late 60s'early70s when tires were made out of very hard, thick rubber, but we've long since left
that technology behind.

BTW, I have found that running my automobile's tires at 35-36 PSI instead of 32 PSI is netting me between 1 - 1.5 MPG better fuel mileage.
On our 2007 Mazda, one cannot tell the difference in ride quality at all, and the tires are rated for up to 42 PSI anyhow so there is no danger.
On my 2000 Nissan truck, the ride is noticeably harsher, but I'll happily take the improvement in gas mileage.
Airhead #12178 ? BMWMOA #123173 ?BMWRA #33525 ?GSBMWR #563 ?1982 BMW R65LS ?1978 BMW R100/7 1998 Kawasaki Concours

Offline Semper Gumby

  • Mt. Olympus Resident
  • ****
  • Posts: 2173
  • Dances with cow!
Re: Innertube or Not?
« Reply #8 on: July 15, 2008, 11:26:54 AM »
+1 with the tubes.
Bill Gould ?1980/03 R65 When at first you don't succeed....Moo!

BigJohn

  • Guest
Re: Innertube or Not?
« Reply #9 on: July 15, 2008, 02:23:45 PM »
If you run your car tires constantly overinflated, yes, you will lower rolling resistance and use less gas. BUT it will also make the center patch of the tire wear out much much sooner and I think the cost of new tires is not going to be favorable versus the small savings in gasoline.  The manufacturers recommended pressure as labeled in the driver's door jam is the best pressure to run and get maximum life from your tires.  The cost of which is going to increase due to their main ingredient being oil.  The pressure listed on the side of the tire is the maximum that the tire maker says it can withstand before having an explosion risk.

Offline nhmaf

  • Global Moderator
  • Mt. Olympus Resident
  • *****
  • Posts: 5156
  • Free at last, Free at last!
Re: Innertube or Not?
« Reply #10 on: July 15, 2008, 07:49:31 PM »
I trust the mfgr of the TIRES, not the auto that they happen to be mounted on, to be the definitive answer on inflation pressure.
Otherwise, you would believe what the F*rd people put on their explorer model SUVs, which resulted in premature tire wear and failure,
and which were determined to be underinflated by the tire mfgr.   If you have a 70s era bike, the placard on it probably shows you to put
26-28 PSI in the tires, which was OK for the ancient rubber of yore, but is not applicable to today's tires on the same bike.

Of course, if one carries anything to one idiotic extreme or another, ride quality, handling, and safety will suffer.

As long as one doesn't go to the limits of the tires, they are not overinflated.  One can also observe the tire profile to
see if it has become convex - it is fairly obvious to me, though perhaps not everyone has worked in an auto garage. Many cars, trucks, and bikes also
have different pressure ratings for different load ratings.    Staying within the nominal range of inflation pressures,
as in this case 35 PSI is only at 83% of maximum rated 42 PSI, there is no danger, and the tire profile is not compromised.
The tires max rating on the sidewall are also derated to provide safety margin for heating up (tire pressure measured cold)
but I am not advocating going near the pressure limit.

Depending on what tires you have, these specific numbers may or may not apply.   Maybe you have tires with lower max pressure, which will
also probably mean that you run them at a lower pressure still.   What I have observed on my vehicles thus far has been that increasing
tire pressure from ~ +/- 76% of rated pressure to +/- 83% of rated pressure  has yielded an improvement of about 3.5 - 4% improvement in fuel
mileage, and so far tire wear does not appear to be affected, though I do monitor how many miles I get out of a set of tires.
Airhead #12178 ? BMWMOA #123173 ?BMWRA #33525 ?GSBMWR #563 ?1982 BMW R65LS ?1978 BMW R100/7 1998 Kawasaki Concours

Crossrodes

  • Guest
Re: Innertube or Not?
« Reply #11 on: July 15, 2008, 08:09:26 PM »
Alright already  :)  I paid $7.50 for an inner-tube and installed it with my new tire.  By the way I've been running my car/truck tires near sidewall max pressure for years.  I get great mileage out of them and they don't wear at the crown...they wear evenly and they run cool on the highway.

OTOH in 2000 when I bought my first Goldwing I ran the first couple of sets of tires at Honda's recommended pressure (36 and 38 I think).  These tires cupped badly and both failed with either a sidewall bubble or a longitudinal split in the tread.  One was a Dunlop and one was a Metzler...both rear tires.  After that I started putting max pressure in these tires...  No more failures and minimal cupping.  

Offline nhmaf

  • Global Moderator
  • Mt. Olympus Resident
  • *****
  • Posts: 5156
  • Free at last, Free at last!
Re: Innertube or Not?
« Reply #12 on: July 15, 2008, 08:57:16 PM »
Glad to hear that you put in the tube !   I think that it is a small, but important safety investment, IMHO.

Many of the modern heavy bikes need alot of air pressure it seems, to avoid scalloping the sides of the tires.
I think that the mfgrs have gotten the rubber tread compound to be quite sticky and pliable and the right
cross sectional profile for handling turning into curves without relying on sidewall flex.  And actually, if the
sidewalls flex on these modern tires, then you DO get excessive movement and the scalloped edge patterns.
So, the ready antidote is to use some more air pressure.   My Kawasaki Concours is not as heavy as a 'Wing,
though it can wear the same size tires as the older ->1500cc Wings and it is very tough on front tires.  It is
around 685 pounds wet and carries alot of weight on the front.   I have to run 40 PSI in the front tire to avoid
scalloping, and generally run 40-42 PSI in the rear tire, too.  This is the "norm" for these bikes, and for others
as well , from checking various internet forums.
Airhead #12178 ? BMWMOA #123173 ?BMWRA #33525 ?GSBMWR #563 ?1982 BMW R65LS ?1978 BMW R100/7 1998 Kawasaki Concours