StromTrooper banner

1 - 20 of 24 Posts

·
Registered
Joined
·
485 Posts
Discussion Starter #1
Got a quick question for the more experience wrenches on the forum...

I installed brand new Shinko 705s front and rear last summer. Around mid-autumn, I got about a quarter mile down the road from my house and noticed that the front tire was flat. Long story short, I re-inflated the tire, sprayed it down with Windex and looked for bubbles, but found nothing. The bike did great for another week or so, when I noticed the front was flat again. Repeat troubleshooting above, and nada again. Next, I released all pressure from the tire, then inflated it with high pressure really quickly, like I was trying to seat the bead (which, in fact, is pretty much what I was trying to do, just in case the bead had broken), but that didn't make any difference. After a few days, there was a noticeable loss of pressure in the tire again.

The first time I noticed the flat was two or three weeks after a trip I took up along Petersville Road -- a thirty-some-odd mile (one way) rough, gravel road (think fire road, and you'll be close). I was definitely pushing the bike on the road, and I did drop the front tire into a good sized pothole at one point. It was a pretty solid hit, and I think I might have bottomed out the (stock) front suspension at about 35MPH.

Based on the problem and circumstances, I'm concerned that I may have either damaged the tire or damaged the wheel, although I am still hoping I only broke the bead. So...how do I go about troubleshooting? Here are my thoughts:

1) Remove and reinstall the tire. If the problem goes away, I only broke the bead. Simple, and best of all, cheap, lol.

2) Replace the tire. If the problem persists, I munged up the wheel on Petersville Road. If the problem goes away, I only munged up the tire. However, it's almost a brand new tire. I hate to buy a new one when I don't know that there's anything wrong with the old one.

3) Take it to a mechanic to troubleshoot. I'd rather not, since I would like to learn to maintain and troubleshoot the bike myself. If I take it to a mechanic, then I have to trust that he actually did a decent job of troubleshooting and that he put everything back together correctly (not a given, in my experience with cars). Besides, I don't learn anything that way. :beatnik:

4) Install a tube and call it good. I really don't like this option, since, if I damaged the wheel (say, a crack somewhere), it could come apart on me at a Most Inconvenient Time (tm) :jawdrop:

Any other troubleshooting options? If this was your bike, how would you proceed?
 

·
Registered
Joined
·
663 Posts
It sounds like a really slow leak.

Mine turned out to be the valve stem. I had replaced the tire but not the stem.

I found it by parking the Vee with the front wheel in a toddler's swimming pool with a 10" lip.
Turned it a bit at a time, about 60psi. Had the " Found it! " moment when the stem was
immersed.

If it is the tire, I'd get a new one. Tube in a radial tire is for emergency repair only, IMHO.
 

·
Registered
Joined
·
1,852 Posts
Valve stems have bit me before as well. I think you need to figure out how to get the wheel, or parts of it at a time, under water. I like the idea above. If it if fact a cracked wheel, that will show up with that method also.

On a separate note, do you need a shop manual for your XS750 project? I've got a couple taking up space.
 

·
Registered
Joined
·
485 Posts
Discussion Starter #4
Valve stems have bit me before as well. I think you need to figure out how to get the wheel, or parts of it at a time, under water. I like the idea above. If it if fact a cracked wheel, that will show up with that method also.
The idea of submerging the wheel had occurred to me, but I couldn't figure out how to do it. The kiddie pool is a great idea; I think I'll give it a try.

On a separate note, do you need a shop manual for your XS750 project? I've got a couple taking up space.
Thanks! I have the Haynes repair manual for the bike, which is...helpful, I guess, although it's not *great*. If you've got a different manual that you would like to get rid of, however, let me know what you want for it. A second point of view or a photo from a different angle can often make the difference between banging your head against the wall for several hours and that "Aha!" moment when it all suddenly makes sense :)
 

·
Registered
Joined
·
1,852 Posts
Both of the ones I have are Clymer's, which may or may not be any better, but you are welcome to one if you want it. PM me your info and I'll find out what it will cost to send it your way.
 

·
Registered
Joined
·
4,326 Posts
Easiest way to find leaks in tyres [or tubes if not running tubeless] is to dunk it in a tank or tub of water- love the toddlers pool idea though :yesnod:
 

·
Premium Member
Joined
·
2,973 Posts
Really sounds like the valve stem, probably the core. Go buy a cap that has the tool built in and tighten it up a schosh.
 

·
Registered
Joined
·
7,442 Posts
Is Windex bubbly enough to spot very small leaks, and do the bubbles have enough viscosity to stick together to be easy to spot? Try your own mix of liquid dish wash detergent and water. And give it time to bubble. If you're really stuck, find some bubble leak detector in the plumbing department of a hardware store. This is made to find very small leaks in piping running natural gas, oxygen, refrigerant gas, etc. Also, the leak could be from something that has punctured the tire but the rubber seals around the item so it doesn't leak when stationary. Rolling makes the hole open up. Take a very close look all around the tread and rim after you've closely checked the stem & core.
 

·
Registered
Joined
·
485 Posts
Discussion Starter #9
PTRider -- very good points. I didn't think of that. Thanks!
 

·
Registered
Joined
·
485 Posts
Discussion Starter #10
OK, it took me a while, but about two or three weeks ago, I pulled the wheel, and dunked it in the bath tub to find the leak (thanks, Austin44 for the idea of submerging the tire! :thumbup: ). It's not the valve stem, there's not a puncture in the tire, and the wheel seems to be fine (other than a few nicks here and there from my first tire change with crappy tire levers, long since replaced with better levers -- which *MIGHT* be a factor, but I'm getting ahead of myself).

The leak is a slow leak between the rim and the tire, one more or less quarter-inch sized bubble every 10 seconds or so. I removed the tire, took some sandpaper to the inside of the rim to smooth it out a little, cleaned up both the tire sidewall and the inside of the wheel with Windex, reinstalled the tire, attempted to seat the bead, burned out my compressor (it was old, and honestly, undersized), took the tire to a motorcycle shop to have them seat the bead...

...and last night, I noticed the tire was flat again :headbang::furious::headbang::furious:

So, I know where it's leaking, but I'm still not sure if it's the wheel or the tire. I'm confident the wheel isn't cracked, so I'm no longer worried about the wheel coming apart on the road, but I still have a couple of options:
  1. Ignore it, topping it off with air every couple of days;
  2. Replace the tire and see if that fixes the problem;
  3. Deflate the tire and insert a tube.
All of these options have downsides, though:
Option 1: What if the problem continues to get worse, until it catastrophically deflates at 70MPH in the mountains? :yikes: I'm not too keen on this option, honestly.

Option 2: if the problem is the wheel, I've wasted $100, and possibly damaged a brand new tire. Like I mentioned earlier, there were some rough spots on the inside of the wheel from the first tire change. I tried to sand them out, and I didn't feel any rough/sharp edges afterward, but I'll be the first to admit, I'm not an experienced wrench, and I don't know if this is an acceptable way to resolve the problem. Thoughts?

Option 3: I've heard vague warnings about running a tube in a tubeless tire. How bad of an idea is this? Why? Does it build up too much heat, and if so, is that much of a concern in an area where a really hot day is 78F?

Once again, thanks in advance for all of the help.
 

·
Premium Member
Joined
·
2,973 Posts
...Option 3: I've heard vague warnings about running a tube in a tubeless tire. How bad of an idea is this? Why? Does it build up too much heat, and if so, is that much of a concern in an area where a really hot day is 78F?

Once again, thanks in advance for all of the help.
On option 3, heat is a function of air temp, pavement temp and speed. If you like to run extended stretches north of 85mph I'd think twice about it, otherwise you're probably fine.
 

·
Registered
Joined
·
177 Posts
If you can't reliably hold air, your wheel may be the culprit. Unlikely the tire bead isn't working - the rim may be compromised somehow with a hairline crack. Don't risk a catastrophic deflation on the road. Tire and wheel condition cannot be ignored.
 

·
Registered
Joined
·
485 Posts
Discussion Starter #13
Don't risk a catastrophic deflation on the road. Tire and wheel condition cannot be ignored.
That's what has me concerned. I'm just not sure how to proceed with troubleshooting from here. I could buy a new tire and see if it holds air, but I thought I'd check here first to see if anyone with more experience working on bikes had a better suggestion. If not...well, $100 is cheap insurance.
 

·
Registered
Joined
·
374 Posts
mark the rim and tire at the leak point. unmount and remount the tire 180 from it's previous position. follow the leak. if it moves 180. its the tire.. if not, its the rim...
 

·
Registered
Joined
·
485 Posts
Discussion Starter #15
mark the rim and tire at the leak point. unmount and remount the tire 180 from it's previous position. follow the leak. if it moves 180. its the tire.. if not, its the rim...
Awesome -- that's a great idea. Thanks!
 

·
Registered
Joined
·
4,033 Posts
Don't blame me if it goes wrong.

IF it's the tire, slather some shoe-goo over the area where it's leaking, let it dry, mount it and retest.

Pete
 

·
Registered
Joined
·
37 Posts
I typically use a Scotchbrite pad to clean up the rim bead area before mounting and then use Crisco solid vegtable shortening (don't laugh it's non-corrosive, slippery, easy to put and keep only where you want it, cheap, and readily available) on the tire bead to help mounting and seating. I second the suggestion of rotating the tire to determine if it the rim or the tire. -- Good luck !!!
 

·
Registered
Joined
·
485 Posts
Discussion Starter #19
What about putting Slime in it? Isn't that supposed to be the messy cure all?
I thought about that, but I would really rather not make a mess inside my rims. Since I typically change my own tires, what would I need to do differently with Slime in the tire? Does it dry or stay a viscous liquid? How does it affect mounting and setting the bead next time around?

Would I use it if I was halfway up the Dalton or Top-of-the-World Highway to patch a hole and limp home? You bet! But while I'm in my garage trying to troubleshoot a slow leak that could mean a problem that I really need to solve anyway...I'd rather not.
 

·
Registered
Joined
·
4,033 Posts
Slime won't help on a rim leak. It's either sitting in a pool at the bottom or gets pushed to the outside when it's rotating. Even if you filled the tire right up with slime it wouldn't help here.


Pete
 
1 - 20 of 24 Posts
Top