Yamaha Grizzly Forum banner

1 - 10 of 10 Posts

·
Premium Member
Joined
·
841 Posts
Discussion Starter #1
On Monday after the mud bog races I noticed that my right rear tyre was flat. I removed the wheel, inflated it and ran water over it to find the leak. It was leaking around the bead of the rim, after I deflated the tyre I could push down on the tyre and found that at the two places where air was leaking there was small pebbles between the rim and tyre!!!!!

Have any of you guys had this problem, it seems that during the races small pebbles were pushed into the joint between rim and tyre and eventually caused the leak.

Any thoughts?

I am taking the tyre into town in the morning to have the bead broken, cleaned up and refitted. On a similar thing, do any of you guys carry tyre changing gear on your longer rides?

Cheers Noel
 

·
Registered
Joined
·
339 Posts
All I carry is tire plugging, inflating, and spare valve stem (don't know exactly how I would install the stem) equipment.

In order to get the dirt into your bead you must have hit something pretty hard that flexed the bead to allow the stuff in there. Probably your tires were a little under inflated also. When they fix your tire you may want to ask them to use bead sealer. It makes a good bond between the rim and tire and is harder to brake the bead with it applied.
 

·
Premium Member
Joined
·
841 Posts
Discussion Starter #3
DKNARND,

I also carry a compressor and plug gear. The tyre may have been slightly under inflated but I run 4lb in them? I did get air bourne a few times so it may have been from landing in the mud ?

I was wondering if anyone takes levers and or a spare tyre on longer rides (1 or 2 days)

Thanks Noel (Bruce)
 

·
Premium Member
Joined
·
841 Posts
Discussion Starter #5
Jim,

I was told to run 4lb because there is less chance of the staking a tyreas alot of the scrub is without tracks.

Cheers Noel
 

·
Registered
Joined
·
339 Posts
Yea with 4lb you are going to see allot more sidewall flex. I generally run 4.5 n the rear and 4.75 in the front on my home turf trails but when I go out in the mud and extreme rocky areas to ride I increase by a pound in each tire.
 

·
Registered
Joined
·
270 Posts
"I was told to run 4lb because there is less chance of the staking a tyreas alot of the scrub is without tracks."

Ok, first off... what does staking a tire mean? And by scrub, do you mean the land you ride in? haha... I need Australian lessons!!!

Second, as for the tires, too low on the pressure you will have more flex. This can cause pebbles in the bead like you got, but more concern for me is that the more flex in the tire, the better the chance my rim will bottom out on a rock and I'll have a repair that is a big pain in the field with just a hammer to bend the rim back. We ride alot of mountain and rock trails and pretty fast at that, so if you looked at my rims, you'd think I was running into the rocks on purpose!

The manual recommends 6PSI. I have so many plugs that I start at 7 psi, after an hour I'm probably at 5 psi, and halfway thru the ride it is time to fill up, haha.

I've had pretty good luck with 6-7psi.

Jim
 

·
Premium Member
Joined
·
841 Posts
Discussion Starter #8
OK Australian 101.

"Staking a tyre" is to run over a tree branch, old fence post etc. and have it spear through the tyre either through the side wall or through the tread.

I have been told that running 4lb allows the tyre to mould to the shape of the stake and lessen the chance of it piercing through.

"Scrub" basically this is our bush, forest, native vegetation.

Our scrub up here is covered in grasses upto about a metre high at the moment so it can be hard to pick your way around if you have to go off the tracks, I normally do this at a slow pace.
 

·
Registered
Joined
·
270 Posts
ok, got you. Like I said, we ride alot of rock trails and the tires are pretty strong. I get sidewall holes from the rocks if the tires are too soft and colapse and I guess you can if they are too hard and dont give. I don't think the actual bottom tread of the tire is going to flex that much to go around a stick or stake and if they can't handle a wooden stake I doubt they are very good tires to begin with.

Good luck whatever you run.

Jim
 

·
Premium Member
Joined
·
2,962 Posts
More than likely, the rocks got in there while you were doing some hard conering. It's common with stock tires because the side walls are so thin and the tire rolls over allowing a small gap between your bead and the rime. Once the rock gets in there, the more you corner the further it can work it's way in.
I'm not sure what kind of tires you are running, but with such a low preasure, you get the same result.
Sometimes the rocks will work themselvs all the way in and you can hear them rolling around in there.
 
1 - 10 of 10 Posts
Top