Project Hellraiser 3

Page 31

   
 
 

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A lot has been going on since my last update, unfortunately little wheeling. Besides a bad strut it seems that I have some defective tires.  We noticed they were starting to separate near the bead area while out at KOH.  I guess this is a known issue and I had a set of replacement tires in a week or so.  I had already decided to throw in the towel on the Pitbulls before the new ones arrived since I could not keep them from burping air with my rims at low pressure.

When the new ones arrived I did some measuring before dropping them off with the new owner and as I suspected the bead is way too thick to work properly with the safety bead profile on my KMC rim shells (17 x 8.5 KMC Enduro). Not counting the huge radius of the rim protector, the tire bead is almost an inch thick while the safety bead area on the rim shell is barely 3/4 of an inch wide so essentially the tire bead sits at an angle never gets a good flat seal.  Any push or tire wrinkle could easily cause the line contact seal to be broken causing the tire to burp air. I would have assumed this kind of thing was a standard but after gathering some more tire measurements I don't think it is. It would be nice if the tire manufacturers and wheel manufacturers got on the same page so consumers doesn't end up with 4 grand worth of rims and tires that do not work together.   Ironically the replacement tires had the same splitting issues which are visible in the picture I took after loading them but before I dropped them off to the new owner. I noticed the crack when I looked at the high res pictures.  Last I heard Pitbull had come up with a stress test to test the tires before they leave the plant so hopefully they have a handle on this issue.

42" Sticky Irok vs. 39" BFG Krawler

Two tires I know work well on the KMC rims are the 42" Irok (sticky compound) and the 39" BFG Krawler.  The bead measurements back this up, both have beads thin enough that  they can drop down into the safety bead profile on the rim shell making for a good seal, I have no measurements yet to back it up but I have heard the Trailready Beadlocks have a larger safety bead profile than the KMC's so they would be better candidates for some of the thicker beaded tires out there (42" Pitbull rockers and 43" SX's).

I had two weeks to kill while I waited for one of my ORI's to get repaired. In anticipation four our trip to the dunes I installed a lighted whip/flag holder.  a half inch hole centered up on the rear storage bin locates the whip.  Next to it I installed a small spring loaded clamp to hold the battery which powers the LED lights in the whip.

I also addressed a few things we noticed after some extended driving in Johnson Valley.  The first was stiffening up the brake pedal assembly.  Anytime you got on the brakes there was a good quarter inch of movement due to the upper mounting bars flexing.  I made a bracket that bolts between the two reservoirs and the pedal assembly mount, then it attaches to the fame via a welded mounting tab. Keeping this piece removable will allow for easier servicing of the master cylinders if needed.

The same flexing was noticed when actuating the steering valve when the engine was off. Although not the typical operating condition, I have had to drive a rig back with a dead engine and when you rely on the internal pump in the steering valve it puts a lot of stress on the mounting bracket. I added another tab which comes off of the engine cage to stiffen the valve mount.

Lastly I looked into the steering/knuckle clearances after noticing some new wear marks on the stub shaft ears.  My brother-in-law Dan spotted the culprit: the Solid Knuckles have more material in than the stock knuckles and when turned hard the stub shaft ears were contacting the knuckle.

The fix was pretty easy, I just got the grinder out and started removing material till there was extra clearance.

I was able to remove the external steering stops on the ram completely and gained a bit more steering angle while utilizing the entire 8" of stroke on the ram.  It looks like I could actually use a bit more stroke if available since the u-joints are not close to binding.

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