motorman587 Posted January 21, 2006 Share Posted January 21, 2006 Going home, 60 mph, about to go into a nice right hand turn sweeper. The Handlebars go from free play to stiff, I knew something was wrong. I start to slow, and get a little wobble. Then it hit me. Flat tire. Happen to me before. Did not panic, pulled over. Yep, front flat, second time. The valve stem bottom had a rip. No way to fix. Keep riding about 40 mph. Feels good. About 15 miles from the house. Tallman sees me, turns around ask if he help, thanks Tim. Made it home, on a flat for about 15 miles. Anyone else had a valve stem failure. Link to comment
DogGone Posted January 21, 2006 Share Posted January 21, 2006 Like I been trying to tell people, them pnuematic tires are a flawed technology. A solid rubber tire wouldn't have had any problem. And BMW refuses to admit there's a problem. Glad everything worked out ok. Link to comment
lithoman Posted January 21, 2006 Share Posted January 21, 2006 Wow!, glad everything turned out OK!! those from what I heard can have catastrophic consequences!! I have not had one myself, but now I kind of know what to expect. glad your OK Link to comment
Jon_M Posted January 21, 2006 Share Posted January 21, 2006 What does your wheel look like after that? Link to comment
HappyMan Posted January 21, 2006 Share Posted January 21, 2006 That had to be tough on the aluminum wheel! Or are you driving a GS with spokes? Inquiring minds want to know. Glad your o.k. Link to comment
lawnchairboy Posted January 21, 2006 Share Posted January 21, 2006 HOLY %$(*&^#@@ BATMAN... I would be changing my drawers after that. Link to comment
Bob Palin Posted January 21, 2006 Share Posted January 21, 2006 That had to be tough on the aluminum wheel! Or are you driving a GS with spokes? Inquiring minds want to know. Glad your o.k. The tyres are incredibly stiff, you can ride slowly on a smooth surface without damaging the wheel. Link to comment
Eschelon1 Posted January 21, 2006 Share Posted January 21, 2006 Nada on the valve stem failure. Glad you made it ok! Link to comment
motorman587 Posted January 21, 2006 Author Share Posted January 21, 2006 Like I been trying to tell people, them pnuematic tires are a flawed technology. A solid rubber tire wouldn't have had any problem. And BMW refuses to admit there's a problem. Glad everything worked out ok. Rim is ok, it was not the tire that had the blow out but the valve stem. I wonder if the little pig as valve stem cap is to heaviy and causing the valve to crack with time. Like I said this twice. Stopped twice to cool the front. The first stop by a Trooper, wanted to know what I was doing in the county. I guess I looked "suspect" cop, civilian clothes, 40mph in a 60, bicycle lane on a wide open stretch of road. Link to comment
Mike_F Posted January 21, 2006 Share Posted January 21, 2006 40mph in a 60, bicycle lane on a wide open stretch of road. Must be nice to be a cop huh? Sad to see the that a ticket was throw out for a bicycle lane violation and we are working two traffic fatalities where the car crossed into the bicycle lane. Folks are complaining about the police or us for not doing our job. Link to comment
MotoBoy Posted January 21, 2006 Share Posted January 21, 2006 Yer' lucky he didn't run you in for vagrancy or defective eequipment or some such!! Seriously, I've got an acquaintance - a very experienced rider - who had a front tire blowout "with no warning" at speed, riding two up. The bike flipped, as they describe it, "instantaneously." Both were in hospital a long time. In such a case, one always suspects underinflation with resultant overheadint of the tire, but a big-time valve stem failre? Yikes! The story I've always heard is to replace 'em any time we've got the tires off the rims, but I'll sure pay more attention. Glad your consequences weren't any worse! Link to comment
motorman587 Posted January 21, 2006 Author Share Posted January 21, 2006 40mph in a 60, bicycle lane on a wide open stretch of road. Must be nice to be a cop huh? How did I know that somebody would take a cheap shot. Will come to this board. First how many person/s do you that has gotten a ticket for riding in the bicycle lane, with a disable vehicle. What is safer? No, I would not write a ticket for, but would stop and ask if I could help, like the Trooper did. I love this place. Sad to see the that a ticket was throw out for a bicycle lane violation and we are working two traffic fatalities where the car crossed into the bicycle lane. Folks are complaining about the police or us for not doing our job. Lets the difference. Wide open country road or the city. Where would a reasonable person think. You sound like my in laws. Link to comment
motorman587 Posted January 21, 2006 Author Share Posted January 21, 2006 Sounds like nobody has this problem either so it maybe the little "pig" valve cap. Must be too much weight and ripping the valve stem. Link to comment
No_Twilight Posted January 21, 2006 Share Posted January 21, 2006 Sounds like nobody has this problem either so it maybe the little "pig" valve cap. Must be too much weight and ripping the valve stem. Not sure what the "pig" is but the centrifugal force on the valve stem at speed is enough to open the valve and deflate the tire. That's why it is important to have a good valve cap on with an o-ring/rubber seal in the bottom of it. I'm starting to change and balance my own tires and I'm going to a metal 90 degree valve stem. --Jerry Link to comment
motorman587 Posted January 22, 2006 Author Share Posted January 22, 2006 Sounds like nobody has this problem either so it maybe the little "pig" valve cap. Must be too much weight and ripping the valve stem. Not sure what the "pig" is but the centrifugal force on the valve stem at speed is enough to open the valve and deflate the tire. That's why it is important to have a good valve cap on with an o-ring/rubber seal in the bottom of it. I'm starting to change and balance my own tires and I'm going to a metal 90 degree valve stem. --Jerry The "pig" is a little gold valve cap, which is in the shape of pig. You know police, pig. I get some laughs from it from two blow valve stems, I may have to remove it. Link to comment
upflying Posted January 22, 2006 Share Posted January 22, 2006 Most if not all RT-P's come with Dunlop D205's with run-flat capability. Probably why you could keep on riding. Link to comment
FlyingFinn Posted January 22, 2006 Share Posted January 22, 2006 The tyres are incredibly stiff, you can ride slowly on a smooth surface without damaging the wheel. Although sometimes this might be the case, I don't think it is universally true. There is HUGE difference in sidewall stiffness between, say Mez ME880 and M1. And I'm sure also most other sport oriented tires have very flexible (and light) carcass making it a bad idea to continue riding (no matter how slow) after tire deflation. -- Mikko Link to comment
2wheelterry Posted January 22, 2006 Share Posted January 22, 2006 I was riding in the Sierra’s a few years back and ran across a guy pulled off the side of the road. He said that his tire had gone flat fast. His rubber valve stem was cut/broken above the rim. He wasn't sure what happened. We speculated a cause, but who knows. Since then I ask for the metal/chrome valve stems. Link to comment
No_Twilight Posted January 23, 2006 Share Posted January 23, 2006 Here are the 90 deg brass ones I bought: http://cgi.ebay.com/ebaymotors/chrome-me...sspagenameZWDVW Sorry for the ebay link that will expire in a couple of days but the current readers can see it. --Jerry Link to comment
RFW Posted January 23, 2006 Share Posted January 23, 2006 The tyres are incredibly stiff, you can ride slowly on a smooth surface without damaging the wheel. Yes you can, surprisingly! Last summer I had a rear tire that got slashed by some kind of sharp object. Went flat instantly. Blowing air into it with the little compressor I carry did nothing. So I rode a couple of KM home on it... slowly! What happens is the tire squashes under the rim, and rolls so it gets between the rim and the road. No rim damage at all, and what was really surprising was that after I removed the tire, other than the slash (which made it useless), there was no damage at all from driving on it flat. Lucky for me, I had already bought a new set, and was only waiting to wring the last few KM out of the old tires. So the flat really cost me nothing since I was going to pur the new ones on in a few weeks anyway. Bob. Link to comment
Dear_Leader Posted January 23, 2006 Share Posted January 23, 2006 Guys I posted about my 2nd front deflate a few weeks ago. I suggets replacing the std rubber valve stem with a metal screw-in stem that cannot perish or break. Stay up Paul Link to comment
No_Twilight Posted January 23, 2006 Share Posted January 23, 2006 Paul, I think it was your post that caused me to order my metal valve stems. Thanks, Jerry Link to comment
gusanito Posted January 23, 2006 Share Posted January 23, 2006 Sounds like nobody has this problem either so it maybe the little "pig" valve cap. Must be too much weight and ripping the valve stem. I'll take a guess. Replacing the valve stem, if it's the same rubber one that my RT has, is a pain if you don't have the right tool. I use a valve stem cap with a small chain and T handle attached to it. Cover the rubber stem seat with rubber friendly o-ring grease, slide it through the rim, screw on the tool and give it a couple of pulls. I can see if you don't have that tool using a screwdriver or something thin to try and persuade the rubber through the rim hole and puncturing it. Just a guess. George Link to comment
Draftermike Posted January 23, 2006 Share Posted January 23, 2006 Yes, I have had a valve stem give out on me. It may be the luckiest thing to happen to me in my life that this thing didn't come apart before it did. The day after riding cross country to the high speed sweepers of Utah and back I found my bike in the garage with the front tire completely flat. The center of the stem wasn't just hanging by a thread it was just sitting in place and no force at all was needed to lift it out. The stem had been in place no more then 22,000 miles and, I don't know, maybe three or so years. My thoughts are that the stem was flawed when manufactured. Link to comment
ogjimbob Posted January 23, 2006 Share Posted January 23, 2006 after 28 years riding bikes and driving vans/cars I have yet to see a reputable dealer NOT replace the tyre valve when replacing the tyres, seems like a sensible precaution to me and after 100,000's of road miles I have never had or witness a valve failure! of course if I had one in the UK I would be fooked as we don't have many smoooth surfaces on our roads Link to comment
Jerry Johnston Posted January 23, 2006 Share Posted January 23, 2006 I had a rear tire go flat near Thompson Falls MT and tried riding 10 miles, it chewed up the side wall so bad there wasn't enough rubber to keep the small bits of gravel from nicking the wheel - not badly but I wished I hadn't done it. Link to comment
Bob Palin Posted January 24, 2006 Share Posted January 24, 2006 I had a rear tire go flat near Thompson Falls MT and tried riding 10 miles, it chewed up the side wall so bad there wasn't enough rubber to keep the small bits of gravel from nicking the wheel - not badly but I wished I hadn't done it. I had a rear tyre (MEZ4) go flat near San Diego and rode it about 15 miles, couldn't even tell I had done it. Link to comment
Jerry Johnston Posted January 24, 2006 Share Posted January 24, 2006 You know what they say........Location, location, location Those California roads just don't have the gravel on them. maybe a difference in tire brand ? The other reason I wouldn't do it was the wheel was so hot it would burn your hand which I figure is hard on bearings. Link to comment
No_Twilight Posted January 24, 2006 Share Posted January 24, 2006 Installed the right angle metal valve stems yesterday. I don't have tires installed yet as I'm still making my balancer. But here is a photo of the valve stems. I think I'll really like the 90 degree feature too. --Jerry Link to comment
Rob L Posted January 24, 2006 Share Posted January 24, 2006 Installed the right angle metal valve stems yesterday. I don't have tires installed yet as I'm still making my balancer. But here is a photo of the valve stems. I think I'll really like the 90 degree feature too. --Jerry I bought a set of those a couple of years ago, but had a problem with the front one contacting the caliper. I ended up placing it at a 45° angle instead of perpendicular to the wheel to gain the needed clearance. Link to comment
Mr. Frank Posted January 24, 2006 Share Posted January 24, 2006 Installed the right angle metal valve stems yesterday. I don't have tires installed yet as I'm still making my balancer. But here is a photo of the valve stems. I think I'll really like the 90 degree feature too. --Jerry On another list I read that the 90 degree valve stems should only be used to inflate the tire. At speed the centrifugal force will bend the valve stem. In at least one case it caused a failure. Link to comment
DavidEBSmith Posted January 25, 2006 Share Posted January 25, 2006 There's 90 degree adapters for inflating (which shouldn't be left on) and there's 90 degree valve stems (which have to be installed and which do stay on permanently). I'm not sure there's any of the latter that fit the holes in the current BMW rims - BMWRich58 was looking into that and I don't remember if he ever found any. Link to comment
SWB Posted January 25, 2006 Share Posted January 25, 2006 There's 90 degree adapters for inflating (which shouldn't be left on) and there's 90 degree valve stems (which have to be installed and which do stay on permanently). I'm not sure there's any of the latter that fit the holes in the current BMW rims - BMWRich58 was looking into that and I don't remember if he ever found any. Dang..that's one more tricket that I just GOTTA have. Just wish I'd done it when I put the last set of tires on. Will have to wait 'til the next set. I always have a nagging bit of trouble trying to get an accurate air gauge measurement, and the angled valves would solve that. Link to comment
No_Twilight Posted January 25, 2006 Share Posted January 25, 2006 Ok. Now you guys have me worried. I guess tomorrow I'll have to do a stress analysis to convince myself that my valve steps won't fail. I agree that the centrifugal force is high. But I think the metal stem will take it. I'll work on it tomorrow but first I'll have to get batteries for my postal scale so I can weight it. IF someone wants to work on the calc for me the only real formulae you need are F=M*V*V/R. The stress is F/A. For those of you who don't believe they make these for our bikes, please note the photo attached to my previous post. --Jerry Link to comment
Dear_Leader Posted January 26, 2006 Share Posted January 26, 2006 This separation of metal valve stem from rubber sleeve is exactly what happened to me recently. What beggers belief is the apparent design that the metal stem is held in plac by the vulcanising friction - i looked hard and could see no evidence of even glue ... By the way my 1st front tyre was more scary - the rubber part sheared off at the rim about 2/3 away round. Very suddenn deflation, a little bit more and ot would have been more like ablow out. Erk! Also I checked with 3 dealers and they all said that value replacement is NOT part of a tyre change ... IMHO BMW are endangering our lives to save about $5 on a bike. Metal screw-through-the-rim valves ought to be mandatory. Cheers Paul PS Not that it matters to me for the next few weeks now that I am bikeless ... :-( Link to comment
DogGone Posted January 26, 2006 Share Posted January 26, 2006 Two words... Solid rubber tires. Never heard of one of them failing. Damn this new technology. pete Link to comment
Dear_Leader Posted January 26, 2006 Share Posted January 26, 2006 Nah they wear too quickly, Wooden rims with steel hooping, them was the days. Of cousre my Dad still swears by the old faithful rounded stone - good for travel, great for milling wheat. Link to comment
No_Twilight Posted January 27, 2006 Share Posted January 27, 2006 Ok. I did a quick calc and at 150 mph you have the equivalent of 18 lbs hanging on the valve stem. That's conservative--it's probably a lot less. and it would take a lot more than 18 lbs to bend it so I'm no longer worried. And I'll repeat one more time--the metal valve stems I'm referring to do indeed screw all the way through the wheel and I've got a photo of one ATTACHED to a previous post in this thread. Cheers--Jerry Link to comment
tallman Posted January 28, 2006 Share Posted January 28, 2006 40mph in a 60, bicycle lane on a wide open stretch of road. Must be nice to be a cop huh? Sad to see the that a ticket was throw out for a bicycle lane violation and we are working two traffic fatalities where the car crossed into the bicycle lane. Folks are complaining about the police or us for not doing our job. Mike, This was in an extremely rural area. Nearest "city" is about 15 miles away. There are about 6 houses that front this road over a 10 mile stretech. The bicycle lane is really a misnomer for a second stripe along the shoulder. When I saw him, looked like he was practicing off road with the RT-P. I had just come from the direction he was heading and there were no bicycles for miles, a handful of cars. Yep, it is nice to be a cop, until the stuff hits the fan. Link to comment
Mike_F Posted January 28, 2006 Share Posted January 28, 2006 I know that there were factors that were involved that I can't Perceive, but don't you think that Phil's situation may have as well? I am not flaming anyone here, just trying to prove a point. John did not witness, nor does he have any idea what the road was like that day, but yet he passed judgement on Phil. What I see from my computer is "I am a cop so I can do what I want" "My situation was different, because it was me and I am a cop" Again not a flame, just calling it how I see it. Didn't mean to put you on the defensive. Link to comment
tallman Posted January 28, 2006 Share Posted January 28, 2006 Not at all. I can see both sides. Link to comment
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