Good points. I can be specification driven at times and things may have to vary for an application. Definitely have some points to look at again !
""I've seen wear on the second rib on bias tires quite a bit, but it is even on both sides of the tire, not only one side."" Yes thats what usually happens but do you remember what the tires were like when new? I had a pair of Firestones from Coker and brand new they had the second rib wear pattern....I think the problem is in the tire..But if it handles real well then ??
Bias Ply tires with their stiff sidewalls are not forgiving for incorrect to the application suspension settings. Solid axle cars were usually positive camber .25-1°. Usually not zero and never negative. If you look up road racing solid front axle cars they actually have quite a bit positive camber. Any of the older solid axle Bugatti or Bentley open wheel racers from the '20s. Lots of positive camber, this kept the steering effort low. I don't see any feathering, so I don't think it is a Toe issue. I would suspect your negative Camber on a solid axle is causing your wear issue, since it is slight, only on one side of the tire tread, and no feathering. Camber angles cause a thrust load which will wear on the tire tread. On a radial tire IFS car a little camber will not cause much or any tire wear. On a solid axle Bias Ply tired car, you are going to have uneven tire wear. With a solid front axle, there really is no benefit to having negative camber. Your King Pin Angle and Camber are what allows for easy turning and good tire wear. My knee jerk reaction is to fix the camber. This will probably improve other aspects of driving the car that you may not even notice. As Pist-n-Broke stated, make sure your Ackerman is correct for your application. Need to fix the engineering before you can adjust it. As for tire wear. Bias Plys are unforgiving, tread tries to roll over but the tire carcass is so stiff it does not allow it so we get this weird kind of underinflated look to the worn thread. But that is normal wear on a BP. Bias Belted tires wear normally by having the rib inside the sidewall rib wear down more so than the rest of the tread. This is a function of the way the tire is made. That stiff sidewall of the Bias ply with the radial belt up the middle of the tread makes the tire wear like that. Every time the car would turn the Bias-Ply carcass with the belt still prevents the tire from rolling over, but the Belted section does its best to stay flat with the road. This was to improve grip and reduce tire drag that BP tires have. What you are seeing with wear is the edge of the belted section wearing tread on the road from lateral grip . These tires would wear evenly like a radial tire save for those two tread ribs, when properly inflated. This improved fuel economy and vehicle performance as the tire tread was kept flat reducing drag and heat buildup.
My books only go back to 35 it calls for 0-1/2 + camber Id have an alinement shop check from the picture it looks like more than 1/2 neg.
Good information ! I was under the impression that a neutral (0) camber angle was desired, and 0.05 negative was close enough. No feathering at all, so after I check some of the mentioned geometry, the axle may have to be adjusted.
With excessive toe wear, you would get a feather-edge across the tire. OP, run your hand across the tires both ways, if it had what I describe you'll feel it.
Yes, it should be higher, I'd say a +.5 to a +1.0 degree. I can go with the scrub theory, bring it up to +.5 and it should improve the wear. I have seen that type of wear before on bias ply tires too.
Gonna check some geometry, then address the camber. I’ll stop by some local rod shops and ask who can properly bend axles locally.
The tire shows text book excessive toe. There's a but,,, Here's the but, those text book images assume that the scrub radius is at least in the ballpark of normal for a street driven car, not normal for a go kart. Your scrub radius is closer to a go kart than a street driven car. Your scrub radius sucks, I posted a link above. Also looking at these pics, the rear tires are plumb, the garage door structure is plumb, the head lights are relatively even as are the car door hinges. The tires are not, they look toed out. So it may be camera lens trickery but nothing but the front tires looks off. Remember excessive toe gives you a camber change due to the king pin inclination. When you start messing around with the scrub radius, you get exaggerated pneumatic trail, this is what the tire sees as its rolling and the forces of physics do their thing as the geometry dictates. You probably can't see the effects nor watch the tire flex as its meeting the road but what you do get to see the evidence of wear on the tire that is doing that. Clearly evident. Looks just like excessive toe wear minus the classic "feathering" feel. No matter what you do you can't/won't change the physics but can re adjust the geometry to dictate something different. Do yourself a favor and check out the link I posted above. After you do tell us the details about the brake kit you used and measure up your scrub radius- post that as well.
31 Vicky, Well done! Outstanding info and laid out in lay man terms covering aspect of movement. I'm impressed young man. If he can't cure his problem now, well,,,, Well done. The Wizzard
Idk but I'd sure like to put my hands on it . Camber wear usually sort of rounds off the inside edge gradually towards the center. That wear he shows for 1400 miles is pretty drastically on the edge with a step. Feathers have a feel, smooth one way rough the other.
14,000 miles, no feathering at all on edges. I’m gonna check the king pin to contact center, then start looking at the camber. Like I stated earlier, it’s 1/2 deg negative now, and everything I’ve read this evening says it should be 1/2 - 1 deg positive, so I gotta look in that direction. You guys have given me some valuable information and an education in matters I had no knowledge ........ big thanks ! I’ll post the results.
the thing is, I had the same wear pattern on one bias tire, the camber was off on one side, so I bent the axle to fix it. it's wearing normally now.
Check some truck shops. I was doing alignments at one for a while, it was quite interesting to learn how to bend an axle.
That’s the part I dread ! Finding someone who has experience and knowledge of bending straight axles. Probably a bit of a lost art.
I don't think I'd be too calm about bending a aftermarket superbell axle. It would get me pretty anxious and I'd find a Henry axle. Just for shits and giggles,,,if it's sitting on level ground toss a level vertical on the tire bulges and see what that says.
You have a cast axle (Superbell), and I don't think you should try bending it. If the car drives nicely, I wouldn't fight it. Just drive it till the tires are gone, then buy another set. Small price to pay for a nice driving experience. Many guys have much worse issues and would love to cope with a small weird wear pattern.
I'll add just a little more to this. Yes I'd check camber across the tire bulge however don't do it after lifting them off the ground and just setting it back down. I would want to point the car strait ahead and roll it forward two full tire rotations and then check it. That puts the casings in a load to duplicate driving conditions. The Wizzard
I always set toe to 3/16" in. Alignments are my day job. Sent from my SM-G925V using The H.A.M.B. mobile app
To me that looks like camber wear meaning that it has excess negative camber (it's not front wheel drive that likes neg camber) and the weight is riding on that second rib. If you slide your fingers sideways aross the tread you can usually pick up the tail tail signs of excess toe in or toe out by catching the feathered edges of the tread and even my old ass eyes don't see any feathering on the tires. Back when I was doing alignments that was one of the first things I did when I got the car on the rack was to slide my fingers across the tread to check for feathering from toe in or out along with picking up any noticeable odd wear pattern. I'm saying that who ever set that axle up with negative camber didn't know what the hell they were doing and were setting it up like you would a new front wheel drive car rather than an I beam axle car.
It appears the camber is the culprit for sure. although the wear reminds me of the old Firestone and Goodyear bias ply belted tires that would wear the second tread faster even with correct alignment, like the polyglass tires>
Notwithstanding the unusual tire wear, those babies have covered 14,000 miles and appear to have plenty left to go. What's a reasonable mileage expectancy? Mileage may vary (can't believe I actually wrote that!). If it's 20-25,000 or so they'll probably be good for that anyway? Arguably a band aid but presumably the tires could be swapped side for side putting the inside wear to the outside, or maybe shaved? Won't go near the tire life (as in time) can o worms! Chris
Toe in varies with different setups that's why specks are different for different cars. The idea is to achieve zero toe when the car is going down the road. I would check with Bell before attempting to bend the axle.
God I love this place! Sunbeam is dead on right. Just changing front wheel back space will require a toe in change. Wish I typed with more than 2 Fingers, I'd have a lot more to say. Somehow I'm just not my normal self this morning. The Wizzard The Wizzard
I have learned if nothing else that the Majority of Hot Rodders have absolutly no idea what a well built and aligned Hot Rod can and should drive like. I think that's why M-2 and Air ride is so widely accepted. I find that very Sad. The Wizzard
The top two photos show a tire that has very noticeable toe i or tow out wear as you can see the rounded edge and can see the "feathering" on the tread where you can slide your fingers one way smoothly but catch the tips of the feathered rubber going the other way. The third photo if it shows up is what we recognize as second rib wear when the front end is aligned right and maybe the tire wasn't rotated early enough. It could be that the air pressure was a bit on the low side so it would give a slightly smoother ride. I'm pretty sure both of those tires were on my mom's boyfriend's old 55 Chevy wagon back years ago before he had radials put on it and he never got rid of anything so I ended up with them to use as rollers for one of my projects.
The Jalopy Journal
