--- In
DSN_KLR650@yahoogroups.com, "revmaaatin" wrote:
> --- In
DSN_KLR650@yahoogroups.com, "E.L. Green" wrote:
> > --- In
DSN_KLR650@yahoogroups.com, "revmaaatin" wrote:
> > One thing I will point out is that running an HD tube in your rear
> > tire at high speeds on the highway will cause a serious reduction in
> > your tire life due to the higher tire temperatures caused by the
> > heavier tube.
> Is your 'thesis' empirical data, seat of the pants, local list
> wisdom? Is there something to read more about this?
Tire temperature data is definitely empirical. With super-heavy-duty
tubes in the back, the tube gets so hot at high speeds that it
actually *melts*. A Conti TKC-80 rear lasted barely 4,000 miles with
the super-heavy-duty tube in it. With a regular tube in it, its
replacement lasted over 6,000 miles.
> Seems to me I vaguely remember that one of the benefits of tubeless
> is reduced tire temp. Does that sound right to you?
That is correct, and that comes from the tire manufacturers themselves
(when explaining why they do not recommend running tubes in tubeless
tires unless absolutely necessary because of wire rims).
> Is it a logical leap that the heavier tube, retains heat etc and thus
> reduces tire life due to hotter tires?
Not a logical leap at all. It agrees with the reported and observed data.
> If I also recall, some ~90% of the flats occur in the rear--due to
> the front tire kicks up the object, the rear tire 'receives' it.
I would say you also have to consider the tire itself. For example, a
TKC-80 has a very stout carcass that will retain a lot of heat
compared to, say, a Kenda 270 that has a very flimsy carcass. In a
K270 I'd probably use heavy-duty tubes front and rear because the
flimsy carcass needs the extra rubber to help prevent flats. I
personally have never had a flat with or without a heavy duty tube in
the rear, but I haven't run flimsy tires like the K270 for a while and
when I did, I ran heavy duty tubes front and rear.
> All things equal; Personally, I would rather replace a tire early for
> wear, than change flats between tire replacements.
I guess it depends on how far you're going. If you're riding within a
few hundred miles of home with cheap tires like a Kenda 270, you're
probably correct. If you're riding thousands of miles from home with a
more expensive tire like a TKC-80 or Avon Gripster, you want all the
tire life you can get, because changing tires in the middle of a
multi-thousand-mile trip is a PITA. And if you're doing an expensive
tire like a TKC-80 you might want to extend its tire life simply
because the bloody thing costs over $150! Luckily TKC-80's are
*stout*, and thus resist flats a lot better than something like a
K270, or I'd have a dilemma for sure.
-E