Slow leak in front tire
William Sitch
Well, I've put about 1000km on the VF750F since I picked it up
two or three weeks ago. It's different from the VF500F, and at first I
didn't like it as much, but it's a kick ass bike and I'm learning to love
it. The weight isn't something that I enjoy (~550lbs), and there are a
couple of peculiarities that I need to get used to.
I rode to a friends cottage in Quebec and ended up doing about 10km on
dirt, gravel, etc. It was scary and rewarding at the same time, but man
did my back and shoulders ever hurt after the overgripping that went on!
Other than that, most of the riding I've done has been highway and misc
touring, with a little commuting and some city riding.
I have a slow leak in the front tire (from 32-25psi in a couple of days,
and down to 5psi in a week or two), and a very slow leak in the back tire
(32-28psi over a couple of weeks). I now carry my mountain bike pump with
me, but it's annoying to keep pumping the thing up. Do I have any options
other than buying new rubber and hoping the rim isn't the culprit?
Another concern I have is the front brake. Under hard-ish braking in
very controlled conditions (read: me practicing), I can feel a pulsing
from the brake. It feels as though it's grabbing and releasing at
different points, but what doesn't make sense is that the grab/release
frequency doesn't seem to be right for the size of the rotor. I'm still
troubleshooting, but the operation of the brake doesn't seem to be
affected.
I locked the front tire in a parking lot while coming to a fast stop, and
quickly feathered it moving again once I heard it chirp. It was comforting
that nothing crazy happened, but I was going in a perfectly straight line,
etc. I locked the back tire a couple of times until I found the right
amount of pressure to keep it rolling. I have had a couple of tight turns
give me the willies, but I'm definitely not pushing the envelope on the
road.
I'm having a blast on the bike. Unfortunately, I'm thinking about
something a little lighter and with a better fairing. Call me crazy, but
I saw the ZX6R compared favourably with the VFR800i in regards to sport
touring.
Anyway, I'm not upgrading for another season or so, but it's fun to think.
--
William Sitch, B.E.Eng. (1999) [Post from: Nortel Networks (CRK/12/1B10)]
M.E.Eng. Candidate, OCIECE http://www.engsoc.carleton.ca/~wsitch
K3
news:9n2rr7$ekl$1...@bertrand.ccs.carleton.ca...
> I have a slow leak in the front tire (from 32-25psi in a couple of days,
> and down to 5psi in a week or two), and a very slow leak in the back tire
> (32-28psi over a couple of weeks). I now carry my mountain bike pump with
> me, but it's annoying to keep pumping the thing up. Do I have any options
> other than buying new rubber and hoping the rim isn't the culprit?
We've got the same problem on the '00 Jeep Grand Cherokee... slow leak... so
slow that two of the local tire shops can't find it. It's been recommended
by both shops to pick up a can of Fix-o-Flat and to ABSOLUTELY remind the
folks during the next tire change that we've used it -- they said that it'll
"piss" the sealant all over the next dude that changes the tire.
--
Kendall F. Stratton III
k...@maine.rr.com
http://home.maine.rr.com/k3
Brian Altenpohl
"William Sitch" <wsi...@lager.engsoc.carleton.ca> wrote in message
news:9n2rr7$ekl$1...@bertrand.ccs.carleton.ca...
> Hey all:
>
> Well, I've put about 1000km on the VF750F since I picked it up
> two or three weeks ago. It's different from the VF500F, and at first I
> didn't like it as much, but it's a kick ass bike and I'm learning to love
> it. The weight isn't something that I enjoy (~550lbs), and there are a
> couple of peculiarities that I need to get used to.
>
> I rode to a friends cottage in Quebec and ended up doing about 10km on
> dirt, gravel, etc. It was scary and rewarding at the same time, but man
> did my back and shoulders ever hurt after the overgripping that went on!
> Other than that, most of the riding I've done has been highway and misc
> touring, with a little commuting and some city riding.
>
> I have a slow leak in the front tire (from 32-25psi in a couple of days,
> and down to 5psi in a week or two), and a very slow leak in the back tire
> (32-28psi over a couple of weeks). I now carry my mountain bike pump with
> me, but it's annoying to keep pumping the thing up. Do I have any options
> other than buying new rubber and hoping the rim isn't the culprit?
Could be one of the following:
1. Tire not mounted properly (poor bead) - you can try to break the
bead, clean the inside of the rim, and the tire itself, and re-seal.
2. Bad RIM (dirty, bent)
3. Bad Tire (junk, or old)
>
> Another concern I have is the front brake. Under hard-ish braking in
> very controlled conditions (read: me practicing), I can feel a pulsing
> from the brake. It feels as though it's grabbing and releasing at
> different points, but what doesn't make sense is that the grab/release
> frequency doesn't seem to be right for the size of the rotor. I'm still
> troubleshooting, but the operation of the brake doesn't seem to be
> affected.
Pulsing could be a few things...
1. Check for air/gunk in your brake line. (doesn't cost a lot to bleed
the brakes and put new fluid in) If you do it yourself, you'll run about
$10 (if you buy good brake fluid) - make sure you get the right type -
probably a DOT 3 or 4 for that bike.
2. Warped rotar/disc... you can either live with it, or get a new one.
This can happen if the bike goes down, or the tire is mounted by a rookie in
a garage, or the rims are mishandled (those are common ones anyway).
3. Brake pads are shot/junk. Check em out.
>
> I locked the front tire in a parking lot while coming to a fast stop, and
> quickly feathered it moving again once I heard it chirp. It was
comforting
> that nothing crazy happened, but I was going in a perfectly straight line,
> etc. I locked the back tire a couple of times until I found the right
> amount of pressure to keep it rolling. I have had a couple of tight turns
> give me the willies, but I'm definitely not pushing the envelope on the
> road.
>
> I'm having a blast on the bike. Unfortunately, I'm thinking about
> something a little lighter and with a better fairing. Call me crazy, but
> I saw the ZX6R compared favourably with the VFR800i in regards to sport
> touring.
>
> Anyway, I'm not upgrading for another season or so, but it's fun to think.
>
> --
> William Sitch, B.E.Eng. (1999) [Post from: Nortel Networks
(CRK/12/1B10)]
> M.E.Eng. Candidate, OCIECE
http://www.engsoc.carleton.ca/~wsitch
Anyway, that is my 2 cents... hope it points you in the right direction.
Cheers,
- Brian
Armin Scheans
news:9n2rr7$ekl$1...@bertrand.ccs.carleton.ca...
>
days,
> and down to 5psi in a week or two), and a very slow leak in the back
tire
> (32-28psi over a couple of weeks). I now carry my mountain bike pump
with
> me, but it's annoying to keep pumping the thing up. Do I have any
options
> other than buying new rubber and hoping the rim isn't the culprit?
Check/replace the valve cores.
----
Armin
DoD #2221
Paul Petach
rain at night.
Most of those chemicals have liquifiers that will eat the wheel rim over time.
You will then need not only a tire but a new wheel also.
Carry a can to get you home. Find the leak and get it fixed. Much safer.
Paul daBare
r_kleinschmidt
> I have a slow leak in the front tire (from 32-25psi in a couple of days,
> and down to 5psi in a week or two), and a very slow leak in the back tire
> (32-28psi over a couple of weeks). I now carry my mountain bike pump with
> me, but it's annoying to keep pumping the thing up. Do I have any options
> other than buying new rubber and hoping the rim isn't the culprit?
We've got the same problem on the '00 Jeep Grand Cherokee... slow leak... so
slow that two of the local tire shops can't find it. It's been recommended
by both shops to pick up a can of Fix-o-Flat and to ABSOLUTELY remind the
folks during the next tire change that we've used it -- they said that it'll
"piss" the sealant all over the next dude that changes the tire.
Assuming it's tubeless, it might be worth dismounting the tire and
taking a look at the rim. I'd had a problem with a slow leak that
got fixed by cleaning some goo off the rim.
The inside of the rim was covered with some sticky stuff that seemed
to prevent the tire bead from really sealing perfectly.
Chris Wells & Shauna Mattie
see if the problem goes away. You will need one of those metal valve cover
that have two little prongs on top. The valve cores have the usual right
hand thread (so turn clockwise to tighten). I have had these loosen up on
several of my vehicles over the years (including bicycle, motorcycle, car
and truck schrader valves).
The pulsing of the brakes sounds like a warped disk. Check the disks for
any obvious dings. Also check the disk mounting bolts VERY carefully for
any damage. FYI another way to warp a disk is from overheating. If the bike
passed a safety then the mechanic probably didn't consider it an immediate
safety problem however if it gets worse then you should probably deal with
it.
Good Luck,
Chris
Kuryliak, Dan [CAR:VG24:EXCH]
>
>
> I have a slow leak in the front tire (from 32-25psi in a couple of days,
> and down to 5psi in a week or two), and a very slow leak in the back tire
> (32-28psi over a couple of weeks). I now carry my mountain bike pump with
> me, but it's annoying to keep pumping the thing up. Do I have any options
> other than buying new rubber and hoping the rim isn't the culprit?
You need to remove the tire and steel wool the inside edges of the rim (assuming it's
a cast wheel) with fine steel wool. The tire sidewall should be clean and free of any
aluminum oxide, dirt or rust. Clean the tire sidewalls with Simple Green. The
aluminum rim can be sprayed with WD40 to make the tire mounting easier and the
bead to form properly after the tire is inflated.
>
>
> Another concern I have is the front brake. Under hard-ish braking in
> very controlled conditions (read: me practicing), I can feel a pulsing
> from the brake. It feels as though it's grabbing and releasing at
> different points, but what doesn't make sense is that the grab/release
> frequency doesn't seem to be right for the size of the rotor. I'm still
> troubleshooting, but the operation of the brake doesn't seem to be
> affected.
Sounds like the rotor is slightly warped or the front cylinder piston is slightly
seized...ie: the floating pads are not pushing the piston back into it's housing
after you take the pressure off the master cylinder. It may be ok for your
style of riding,provided you know where the braking thresholds are. If you want
more sensitive feel to the brakes, then it's time for a overhaul, which can get expensive
if the rotor(s) are slightly warped.
Dan K.
--
********************************************************************
Dan Kuryliak da...@NortelNetworks.com
karen hall
tire. Those tools are readily purchased from CDN Tire for what $5.00?
Once you've eliminated the easy, go for the more time consuming and
difficult;rims, tires etc.
Good luck. Happy Riding.
----------------------------------------------------------------------
Math ap Mathonwy Y Draig Goch.`Y Gwir Yn Erbyn Yn Byd'.
Anghared Yr Hen Ddihenydd
B.A (Hons.) Art History
----------------------------------------------------------------------
r_kleinschmidt
> William Sitch wrote:
> > Another concern I have is the front brake. Under hard-ish braking in
> > very controlled conditions (read: me practicing), I can feel a pulsing
> > from the brake. It feels as though it's grabbing and releasing at
> > different points, but what doesn't make sense is that the grab/release
> > frequency doesn't seem to be right for the size of the rotor. I'm still
> > troubleshooting, but the operation of the brake doesn't seem to be
> > affected.
>
> Sounds like the rotor is slightly warped or the front cylinder piston is slightly
> seized...ie: the floating pads are not pushing the piston back into it's housing
> after you take the pressure off the master cylinder. It may be ok for your
> style of riding,provided you know where the braking thresholds are. If you want
> more sensitive feel to the brakes, then it's time for a overhaul, which can get expensive
> if the rotor(s) are slightly warped.
You might try putting the bike on the centerstand and looping a
rubber band over the brake lever to keep the front brake lightly
applied. You now ought to be able to spin the wheel and see the
points where resistance increases and decreases. The rotor could
be warped or the whole disk may be slightly cocked.
SG
the leak first. I had a tire with a slow leak due to a bad rim. You
could see the leak in the rain as the water would bubble. You should
be able to find the leak with some soapy water if it is the rim or
bead.
In article <9n2rr7$ekl$1...@bertrand.ccs.carleton.ca>, William Sitch wrote:
>Hey all:
Kuryliak, Dan [CAR:VG24:EXCH]
> You might try putting the bike on the centerstand and looping a
> rubber band over the brake lever to keep the front brake lightly
> applied. You now ought to be able to spin the wheel and see the
> points where resistance increases and decreases. The rotor could
> be warped or the whole disk may be slightly cocked.
Most of the earlier (non-floating) thin rotors warp to some degree.
This is normal "wear and tear", provided the warpage does not exhibit
a serious lever pulsation that detracts from the sensitivity feel of the brakes.
On the older bikes, the stainless rotors were thick enough that this was never
really a problem, but then in the mid 90's they came out with the thinner
rotors that were not considered floating and the models of bikes that have
those equipped would have some warpage. All the newer ones have floating
rotors where the rotors are not one piece attached to the hub, but assembled in
two pieces.
William Sitch
: I have a slow leak in the front tire (from 32-25psi in a couple of days,
: and down to 5psi in a week or two), and a very slow leak in the back tire
I haven't had any time to play Mr. Fix-it, but I have found some time to
do a little riding. *grin*
Unfortunately the leak is now a big deal and requires some real attention.
I'm getting good at feeling when the tire is low, though, as it starts to
wallow in corners, and the bars get a lot harder to push around corners.
Anyway, thanks so much for all the great ideas. I'm going to try soaping
and looking, examining/replacing the valve cores, and if that doesn't work
I'll try taking the tire off and mucking with it further.
I guess it's a good thing it's the front tire. How hard are they to
remove?
01d...@my.house
Sitch <wsi...@lager.engsoc.carleton.ca> casually remarked:
>In ott.motorcycles William Sitch <wsi...@lager.engsoc.carleton.ca> wrote:
>: I have a slow leak in the front tire (from 32-25psi in a couple of days,
>: and down to 5psi in a week or two), and a very slow leak in the back tire
>
>I haven't had any time to play Mr. Fix-it, but I have found some time to
>do a little riding. *grin*
>
>Unfortunately the leak is now a big deal and requires some real attention.
>I'm getting good at feeling when the tire is low, though, as it starts to
>wallow in corners, and the bars get a lot harder to push around corners.
>
>Anyway, thanks so much for all the great ideas. I'm going to try soaping
>and looking, examining/replacing the valve cores, and if that doesn't work
>I'll try taking the tire off and mucking with it further.
>
>I guess it's a good thing it's the front tire. How hard are they to
>remove?
1. Remove the caliper, tie wrap it to the fork or foot rest so it
takes the pressure off the brake hose(s).
2. Disconnect odometer cable.
3. Loosen axle bolt (check for cotter pin first, remove if there).
4. Pull axle out, tire will fall.
5. Reverse to install.
For a slow leak, once the tire is off, I'd use a large washtub or even
the bathtub. Fill it with enough water to submerge the first 5" or so
of the tire (or to cover the lower part of the rim). Roll the tire in
the water and look for bubbles. Very fast and easy way to figure out
where the air leak is coming from.
cheers,
-aki
Kuryliak, Dan [CAR:VG24:EXCH]
> In ott.motorcycles William Sitch <wsi...@lager.engsoc.carleton.ca> wrote:
> : I have a slow leak in the front tire (from 32-25psi in a couple of days,
> : and down to 5psi in a week or two), and a very slow leak in the back tire
>
> I haven't had any time to play Mr. Fix-it, but I have found some time to
> do a little riding. *grin*
Don't use that Mr. Fixit crap on a motorcycle tire! Your life is worth more than a $%%^&&
$2.50 can of goo that may or may not solve the problem! Take the front wheel off and remove
the tire with a good set of tire irons, clean the rim and the tire sidewalls if that's the problem.
If you have cracked sidewalls..discard the tire immediately and get a new one. You can get
a decent Bridgestone Spitfire tire for under $200.
>
>
> Unfortunately the leak is now a big deal and requires some real attention.
> I'm getting good at feeling when the tire is low, though, as it starts to
> wallow in corners, and the bars get a lot harder to push around corners.
Don't ride the bike with a questionalble front tire. You WILL lose it sooner or later on a
corner when you least suspect it. Tire pressures are very important on motorcycles. They
should be checked each time ride (preferred) or at least weekly on a maintenance basis.
>
>
> Anyway, thanks so much for all the great ideas. I'm going to try soaping
> and looking, examining/replacing the valve cores, and if that doesn't work
> I'll try taking the tire off and mucking with it further.
Pull the front wheel off and inflate it to the recommended pressure (ie: 33psi).
Put the tire in a bathtub filled with water and rotate the tire checking for leaks around
the rim and the valvestem. If the tire has a tube, the tube will need to be discarded and
a new tube purchased. If the tire is a tubeless type, then the leakage could be from around
the rim, or the valvestem/valve or the sidewalls of the tire. A minute crack (not visible to the
naked eye) on the tire tread or sidewall is all it takes to bleed off the pressure.
>
>
> I guess it's a good thing it's the front tire. How hard are they to
> remove?
>
You need to undo, the speedo cable the front axle bolt nutm pull out the axle shaft with
the front forks lifted up a bit. To lift up the front forks a bit, put a cement block and some
boards under the front of the bottom of the engine oil sump. The other thing you may have to
do is to remove the caliper from the front disk to remove the wheel easier. Get some rope
and suspend the caliper off the forks to reduce stress on the rubber brake line.
That's pretty much it as far as removing the front wheel. You need to get some tire irons at
a motorcycle dealer (or make some yourself out of spring steel) to remove the tire off the rim.
It's not hard but can be tricky. Just don't go using sharp tipped screwdrives on a aluminum rim,
as any damage to the rim (or tire bead) will comprimise the seal.