Camber adjustment

[rnet]

I have been asked how I have made camber adjustments on my Spyder since BRP says there are no adjustments. My goal was to make the front suspension with 1/2 degree negative camber. There are two bolts just under the upper A-arm that hold the upper support to the knuckle, you need to place a shim (washer) between these 2 parts. I removed the bolts and put a washer there and replaced the bolts. You may have to play with washer thickness to get the camber you need. What this does is push the top of the knuckle out and therefore pushing the top of the tire away from the chassis. I hope this answer those that asked.

 

[NancysToy]

I always figured this might be possible with either alignment shims or washers. Shims would not require the complete removal of the bolts, but the slots may be a bit too large for the smaller Spyder bolts. Thanks for confirming the theory. How did you measure the camber, magnetic protractor on the hub or brake disk? BTW, theoretically the caster is slightly adjustable, too. The manual has a procedure and a spec, for use when installing new suspension arms.

 

[rnet]

I always figured this might be possible with either alignment shims or washers. Shims would not require the complete removal of the bolts, but the slots may be a bit too large for the smaller Spyder bolts. Thanks for confirming the theory. How did you measure the camber, magnetic protractor on the hub or brake disk? BTW, theoretically the caster is slightly adjustable, too. The manual has a procedure and a spec, for use when installing new suspension arms.

My method was rather crude, I had the spyder on a flat plane and used a framing square with a tape measure. I now have a magnetic angle finder, but now I must be level.

 

[NancysToy]

My method was rather crude, I had the spyder on a flat plane and used a framing square with a tape measure. I now have a magnetic angle finder, but now I must be level.

The caster adjustment procedure uses the magnetic protractor on the bottom of the frame to set the level, then measures at the spindle. I'm sure you could do the same thing with camber.

 

[zmracing]

Why do want to have any camber on the front wheels?

 

[bikeguy]

I may be all wet here, so correct me if I am. I thought that pushing the top of the tire away from the chassis would produce positive, not negative camber. And that pushing the top of the tire toward the center of the vehicle would produce negative camber. Maybe I've forgotten all that I ever learned about chassis setup or maybe I never really learned it at all but I thought that a small amount of negative camber would make for better cornering traction even though it might cause some uneven tire wear. I can't think of any reason to add positive camber since it would also cause uneven tire wear and would hurrt rather than helping front end cornering traction. Did I waste my time reading all those Smokey Yunick books while I was trying to get those old dirt modifieds to turn? Or has it been long enough that I forgot everything?

Cotton

 

[SPYDERPOPS]

Top out makes more positive camber. It already has too much positive camber!


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I am here: http://maps.google.com/maps?ll=34.436733,-93.277810

 

[rnet]

I may be all wet here, so correct me if I am. I thought that pushing the top of the tire away from the chassis would produce positive, not negative camber. And that pushing the top of the tire toward the center of the vehicle would produce negative camber. Maybe I've forgotten all that I ever learned about chassis setup or maybe I never really learned it at all but I thought that a small amount of negative camber would make for better cornering traction even though it might cause some uneven tire wear. I can't think of any reason to add positive camber since it would also cause uneven tire wear and would hurrt rather than helping front end cornering traction. Did I waste my time reading all those Smokey Yunick books while I was trying to get those old dirt modifieds to turn? Or has it been long enough that I forgot everything?

Cotton

You are correct but most people have to much negative camber. Yes you need slight negative for good corner, my goal was 1/2 degree negative. The more aggresive you ride the more negative, just look at the nascar, now there are some radical setups. It all about contact patch.

 

[rnet]

Top out makes more positive camber. It already has too much positive camber!


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I am here: http://maps.google.com/maps?ll=34.436733,-93.277810

I will look at this today to see if there an easy answer for those that have positive camber, but all I have ever read on here is about inside tire wear and most of that is a toe-out problem and to much negative camber, but each case is different.

 

[Bob Denman]

Could this be why we see so much in here about wearing the inside edges of the tires? (Or is that primarily an alignment issue?)

 

[rnet]

Could this be why we see so much in here about wearing the inside edges of the tires? (Or is that primarily an alignment issue?)

Mostly alignment issues. Some with lots of miles could also have suspension wear that plays into it.

 

[Bob Denman]

Thanks! I was wondering about this because negative camber (or too much of it!) would definitely lay that inside edge of the tire down on the pavement in a pronounced manner... That; and I watch too much NASCAR; where they always blame camber as to why they chew the insides of the tires up. :shocked:

 

[NancysToy]

One way to tell whether the inside tire wear is due to inadequate toe-in or excessive negative camber is to examine the tire wear. A camber problem usually wears fairly evenly across the tire, feathering (angling) each tread bar...at least at the initial stages. Feel or look at each row of tread. If each one is angled slightly in the same direction, you probably have a camber issue. This is for mild variations. Badly misaligned suspension will not show these subtle signs. Inadequate toe-in will usually wear only the inside tread bars. Most of the time both tires will wear. There may be feathering of the inside tread row, but the outer tread rows will normally not be feathered. Wear of one tire alone usually indicates worn (or damaged) suspension components on that side.

The tricky part is that a vehicle can have multiple alignment issues, which muddies the waters terribly. The Spyder adds to this with the possibility that the steering sensors could be improperly set or calibrated. You can't readily analyze the tire wear when there are multiple problems, or if the steering sensors are off. Careful sensor calibration (with the steering accurately centered) and alignment measurement is the only way to weed things out. If there is one thing I would like to see in future Spyders, it is fully adjustable alignment, and the tools to measure it accurately and properly...preferably with the suspension loaded and the wheels mounted.

 

[rnet]

Good ideas all around, I do my suspension loaded all the time.

 

[rnet]

I will look at this today to see if there an easy answer for those that have positive camber, but all I have ever read on here is about inside tire wear and most of that is a toe-out problem and to much negative camber, but each case is different.

I see no easy answer for a positive camber problem.

 

[bikeguy]

First, I want to apologize to rnet because I misinterpreted what he was saying in his initial post. I thought his goal was to have about 1/2 degree of positive camber despite the fact that he clearly said negative camber. Sorry, just misinterpreted what you were saying, rnet, and this has been a very interesting discussion.

I spent a little time looking at my RT and I would agree that you should be able to add positive camber by placing a washer or shim as rnet said. I agree with Scotty that it would be nice if BRP had provided a way to adjust both camber and caster. Not having any better way to check the camber on mine, I used rnet's framing square method and found the left (driver side on a cage) wheel to have a bit less than 1/8 inch of positive camber. I didn't have a protractor to convert that measurement to degrees and I don't think it's very accurate anyway. What was really odd to me is that, using the same method and after assuring that both front tires were inflated to the same pressure, the right front appears to have no camber at all. In other words, the right front is straight up and down while the left front is leaned very slightly out. I guess that's something I should try to correct -but - -. My front tires have just over 20,000 miles with very even wear and look like they may be good for another 10,000. It tracks straight down the road even in pretty strong crosswinds and backwash from trucks, and it corners well. Maybe uneven camber is the hot setup. (In truth, I expect my measurements are wrong.)

Cotton

 

[rnet]

First, I want to apologize to rnet because I misinterpreted what he was saying in his initial post. I thought his goal was to have about 1/2 degree of positive camber despite the fact that he clearly said negative camber. Sorry, just misinterpreted what you were saying, rnet, and this has been a very interesting discussion.

I spent a little time looking at my RT and I would agree that you should be able to add positive camber by placing a washer or shim as rnet said. I agree with Scotty that it would be nice if BRP had provided a way to adjust both camber and caster. Not having any better way to check the camber on mine, I used rnet's framing square method and found the left (driver side on a cage) wheel to have a bit less than 1/8 inch of positive camber. I didn't have a protractor to convert that measurement to degrees and I don't think it's very accurate anyway. What was really odd to me is that, using the same method and after assuring that both front tires were inflated to the same pressure, the right front appears to have no camber at all. In other words, the right front is straight up and down while the left front is leaned very slightly out. I guess that's something I should try to correct -but - -. My front tires have just over 20,000 miles with very even wear and look like they may be good for another 10,000. It tracks straight down the road even in pretty strong crosswinds and backwash from trucks, and it corners well. Maybe uneven camber is the hot setup. (In truth, I expect my measurements are wrong.)

Cotton

No apology needed, but after your post I did go back and checked my post to see if I had misspoken. I figured you read it wrong, anyways with mileage like that, I would not touch anything with your alignment, it's close. Mine had a 1/2" of toe-out and the left wheel (sitting on it) had almost a 1/4" of negative camber (difference, top of wheel / bottom of wheel) and almost worn out at 5000 miles. I still have to much negative camber on the right side, but need to find a thinner washer. Most of my wear came from the toe-out.

 

[bikeguy]

No apology needed, but after your post I did go back and checked my post to see if I had misspoken. I figured you read it wrong, anyways with mileage like that, I would not touch anything with your alignment, it's close. Mine had a 1/2" of toe-out and the left wheel (sitting on it) had almost a 1/4" of negative camber (difference, top of wheel / bottom of wheel) and almost worn out at 5000 miles. I still have to much negative camber on the right side, but need to find a thinner washer. Most of my wear came from the toe-out.

I can see where that much toe-out combined with that much negative camber would wear out a tire quickly, especially one with motorcycle compound and construction. You might try thinning down a washer if you can't find a thinner one. It would be hard to do and dangerous on a grinder but if you have access to a belt sander it might work. Even a file with the washer clamped up in a vice although it would take some time.

Cotton

 

[rnet]

What i will do is take stainless steel sheet metal the thickness I need and use a knock out punch to make my own washer when I find the time this winter.

 

[Rayelljay]

With respect may I suggest a thin tapered washer and the use of U-shaped shims made from Feeler gauge stock....?