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low tyre pressure, bead problems [ tyre guru's]

Posted: Thu Aug 26, 2004 1:13 pm
by Old Yella
After spending 2 hours seaching for any ideas to keep my Simex ET's from popping beads or spinning on the rims at low pressure, I was thinking of trying some simex heavy duty tubes. Does anyone have any other suggestions, or ideas :?

My tyre are 16x35 inch ET's on 16x8 inch rims, and If I run lower than 12 psi I have problems. I also thought about going to 7 inch rims aswell.
I don't want to beadlocks as I will be bying 15 inch rims next and I will beadlock them.

Posted: Thu Aug 26, 2004 1:23 pm
by Gwagensteve
Ah, the falling off Simex syndrome.

IMHO, Simex's are renowned for falling off rims. Tubes may help a bit, as you won't loose pressure instantly when the tyre lifts off the rim momentarily, but you will run the risk of pinching the tube when this happens and then having a harder to repair flat as the tyre needs to be dismounted and the tube rpaired, replaced or a tubeless valve stem installed.

I would try glueing the tyre to the rim with urethane/sikaflex/no more gaps etcetc, or fit Moroso Rim Screws or similar. Neither of these are paricularly prett, but they do work.

LJXtreem recently spent a weekend driving around the highcountry with 2psi in the front and 1.5psi in the rear of his TSL/SX's, with no problems. (urethaned inside and outside beads.)

Posted: Thu Aug 26, 2004 1:27 pm
by Old Yella
would the urethane make it a real bugger to get the tyre off If needed :?

someone mentioned sikaflex to me but it just makes a big mess to clean up later.

Posted: Thu Aug 26, 2004 1:37 pm
by Gwagensteve
Yes, probably, but thinners will strip it.

You can't have everything and not have some form of compromise- i.e a mess, difficult to remove tyres or holes in the rim. At least urethane is the only 100% legal beadlock.

Even "real" beadlocks can be a PITA- that goes for bolted beadlocks (own 2 sets) and second airs. (quite apart form the legality, leaks, borken bolts, pinched seconad air tubes etcetcetcetc)

There is an "official" bead sealer product available that tyre shops use. No idea where to get it though, and I don't think this is really a glue, more just a sealer for annoying bead leaks.

I am guessing that with a 'lux, you won't be gettingthe best out of the tyres until you are under 10PSI, so stick with it ('scuse the pun :oops: ) becuse there is a lot more traction to be had.

Posted: Thu Aug 26, 2004 1:38 pm
by Gwagensteve
PS how often do you want to pull the tyres off? I never had a swamper off my beadlocked rims for 5 years (after I got the rims sorted)

Posted: Thu Aug 26, 2004 1:48 pm
by Old Yella
I've mainly only had them off to clean the bead, I suppose if the bead don't break then you don't need to clean them :roll:

Posted: Thu Aug 26, 2004 1:52 pm
by Gwagensteve
Yup. that's about it. Plus, you are not very likely to puncture a 'pede either. (esp a puncture you can't repair with a tubeless repair kit from outside)

It will be possible to get them off, just harder (that's our opinion anyway, haven't tried though)

Posted: Thu Aug 26, 2004 4:36 pm
by 4sum4
I just bead locked mine and I`m glad I broke the bead cause when I did it was full of mud wich will still happen with the Internall bead locks so when you get`em try the external ones if its a option.

Posted: Thu Aug 26, 2004 4:56 pm
by Guy
Gwagensteve wrote:Yes, probably, but thinners will strip it.

.


I was using some urathane glue not so long ago that thinners would not touch (had it all over my hands .. and dont ask) brakleen etc .. noting would budge it except the green scrubber things..

Posted: Thu Aug 26, 2004 6:47 pm
by MissDrew
7 inch rims with the centre turned around as the inner bead has a longer flat section on it so the tyre has to push further away from the bead before it lets go. Not Ideal but it does work better then standard rims, another bonus from doing this is it allows you to get more offset on the rims.

Posted: Thu Aug 26, 2004 9:07 pm
by eddie
if u are spinning ya tires, even putting in tubes wont help
all u will do is rip the valve off the tube when the tire spins,
will help with keeping on the bead when u drop the air but as for spinning,,,,,,, no go

Posted: Thu Aug 26, 2004 9:49 pm
by Old Yella
so who here has Sikaflex'd their tyres on .......

maybe tubes and some bead adhesion :? .......


anyone else have any suggestions

Posted: Fri Aug 27, 2004 5:36 pm
by AndrewT
I ran my centipedes with tubes for a while but after every comp would have to remove and clean the bead etc.

Mechanical beadlocks are the go. Nice and simple, no tubes to pinch or puncture. Everybody worries about them being illegal but if your rigs running 35's it aint legal anyway. I run mine on the patrol at 8 and 10psi all the time and havn't had a problem yet.

Posted: Wed Nov 10, 2004 12:07 pm
by Old Yella
after running tubes in my centipedes at 12psi at the Nissan Trials I had only one tyre spin on the bead, the passenger side rear but it didn't break off the valve stem. I just had to deflate it and pull the valve stem out properly and inflate again.

Posted: Wed Nov 10, 2004 1:29 pm
by hottiemonster
Old Yella wrote:after running tubes in my centipedes at 12psi at the Nissan Trials I had only one tyre spin on the bead, the passenger side rear but it didn't break off the valve stem. I just had to deflate it and pull the valve stem out properly and inflate again.


thats simple enough, i have only rolled one tyre off my beadlocks and then i had a problem about it leaking air when i put the bead on coz the outer ring was bent from the rock i hit, but its all good now. i rolled a tyre off at 15psi and i run 8-10 most of the time and have no problems, its got me stuffed . but hey, it happens

or another idea is, just dont run your tyres so low :lol:

Posted: Thu Nov 11, 2004 2:34 am
by Patroler
I'm running simex tubes in my 36x12.5's on 8" rims, the car weighs about 2200kgs and i was running them at about 6psi in the sand and a short drive through town a week ago, when i went to inflate a couple of them had turned slightly - valve stem on a slight angle, nothing too major though - considering the back moved under acceleration and the front moved the opposite direction (braking) i might just rotate them front to back the next time i try these pressures and see if they straighten :armsup: