I've got a 1980 R65 in fantastic shape, in fact over 3k has been spent on it in the last 5 thousand miles bmw techs getting everything shipshape; (it has 37k on it right now) however, it has one annoying characteristic: going over bumps, I hear a "clunk" in the front end. Fluids are fine, everything's tight and bearings are fine. Someone said what I was hearing was simply the fork legs topping out. Does that make sense? Is this a common problem? Is it even a problem? Thanks!
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r65 front end noise, "the clunk"
- Thread starter devo
- Start date
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BMWRich58
Guest
it has one annoying characteristic: going over bumps,
...have you checked to make sure your brake rotor's aren't loose??
on a floating rotor the buttons/bobbins will wear and allow the rotor to have forward and aft movement, and wiggle side to side,rattling over even the smallest bumps.
Feel with your hands for movement.
Then next time riding over bumps,apply slight braking pressure at the same time and see if the noise subsides.
...have you checked to make sure your brake rotor's aren't loose??
on a floating rotor the buttons/bobbins will wear and allow the rotor to have forward and aft movement, and wiggle side to side,rattling over even the smallest bumps.
Feel with your hands for movement.
Then next time riding over bumps,apply slight braking pressure at the same time and see if the noise subsides.
YOCKYRIDES
New member
R65 Front End Noise, "The Clunk"
That model definitely did not have a floating rotor unless someone did some aftermarket magic. Probably is those bumpers.
That model definitely did not have a floating rotor unless someone did some aftermarket magic. Probably is those bumpers.
I experienced that years ago. The rubber pad that cushioned the front "bracket" that the front of the tank rests on, had slipped off and the tank rattled at different times. New pad, noise stopped. 
Just a follow up to russphoto's post.
Forks bumpers (or even lack of enough pre-load?) sounds plausible too, if it's not that, it's probably something else
Let us know what you find out.
Just a follow up to russphoto's post.Forks bumpers (or even lack of enough pre-load?) sounds plausible too, if it's not that, it's probably something else
Let us know what you find out.
LORAZEPAM
leave my monkey alone
I have a 1984 R80ST, and I can darn near bottom the forks out just pushing down on them. I am over 220 pounds. The bike supposedly had new fork seals installed. I am wondering if replacing the fluid to 10wt and adding aftermarket springs would be the best route to go.
My guess is that the springs are "worn out" and if original they are kinda "spongy" from the factory anyway...
On my '84 R80RT I went to Progressive Suspension's triple-rate progressive springs in the front and a slightly heavier oil trying to minimize front end dive under braking. (Which I would think would translate to your situation of being able to bottom out the front end just pushing on it.)
Forgive me if you already know, but in case progressive springs doesn't ring a bell: from one end of the spring to the other it is wound progressively tighter, so that one end of the spring has one rate and the other is higher at the more tightly wound end... Thats dual or double rate in one spring, then with the triple rate setup, there is a real tight short spring which provides the 3rd rate of spring - order is softer at bottom, tighter at top, in the forks. They also supply (or you can cut) short sections of PVC pipe to "preload" the springs with (goes in the top, last thing before fork caps). It takes a little fooling with and even removing and shortening (or cutting a longer) pieces of PVC pipe, then ride and see how it feels - but you can really adjust the front end to your riding style. That was a long time ago and there mey be newer tech products out there, but I think this is at least one good option for you. All of this can be done without removing forks-it's done through the top fork openings.
I have no experience with pneumatics, etc. for the front end, so can't offer anything there. Best of luck.
On my '84 R80RT I went to Progressive Suspension's triple-rate progressive springs in the front and a slightly heavier oil trying to minimize front end dive under braking. (Which I would think would translate to your situation of being able to bottom out the front end just pushing on it.)
Forgive me if you already know, but in case progressive springs doesn't ring a bell: from one end of the spring to the other it is wound progressively tighter, so that one end of the spring has one rate and the other is higher at the more tightly wound end... Thats dual or double rate in one spring, then with the triple rate setup, there is a real tight short spring which provides the 3rd rate of spring - order is softer at bottom, tighter at top, in the forks. They also supply (or you can cut) short sections of PVC pipe to "preload" the springs with (goes in the top, last thing before fork caps). It takes a little fooling with and even removing and shortening (or cutting a longer) pieces of PVC pipe, then ride and see how it feels - but you can really adjust the front end to your riding style. That was a long time ago and there mey be newer tech products out there, but I think this is at least one good option for you. All of this can be done without removing forks-it's done through the top fork openings.
I have no experience with pneumatics, etc. for the front end, so can't offer anything there. Best of luck.
I'm assuming if it's a 1980 model, it has the ATE brake caliper(s) If it has Brembos, disregard all that follows:
The ATE caliper is supported by an eccentric shaft. The caliper has little plastic rubbing blocks to help prevent clunks when it shifts position. However, the blocks wear, and they are somewhat off the centerline. So, the caliper can make a noise.
I've inserted fiber washers on the shaft at both ends of the caliper, to take up the slack. They need to be the correct thickness, and it's a little difficult to get them inserted while sliding the shaft back through the caliper, but the result is a quieter caliper.
The brake pads on ATE calipers aren't secured very tightly, and the metal backing can make a noise as it moves around.
So, wiggle the caliper(s) around and see if the clunk is coming from that area.
Note that the ATE calipers need to be aligned by unscrewing the cap/spring and turning the eccentric shaft until the fixed brake pad makes best contact with the disc. The pad on the piston will align itself.
pmdave
The ATE caliper is supported by an eccentric shaft. The caliper has little plastic rubbing blocks to help prevent clunks when it shifts position. However, the blocks wear, and they are somewhat off the centerline. So, the caliper can make a noise.
I've inserted fiber washers on the shaft at both ends of the caliper, to take up the slack. They need to be the correct thickness, and it's a little difficult to get them inserted while sliding the shaft back through the caliper, but the result is a quieter caliper.
The brake pads on ATE calipers aren't secured very tightly, and the metal backing can make a noise as it moves around.
So, wiggle the caliper(s) around and see if the clunk is coming from that area.
Note that the ATE calipers need to be aligned by unscrewing the cap/spring and turning the eccentric shaft until the fixed brake pad makes best contact with the disc. The pad on the piston will align itself.
pmdave
86 R65 front rattle
After beating my head against the wall all yesterday afternoon trying to find my front rattle, I would like to share the culprit. Just finished getting this beauty going after a dozen years of neglect. On first test ride I heard a rattle that sure sounded like it was coming from caliper which I just rebuilt. Tried disc brake quiet, removed headlight, checked under tank, and even removed alternator cover thinking something was rattling around in there. It ended up being the aluminum plate held by 4 screws between forks just above fender was loose. Tightened up, rattle gone.
After beating my head against the wall all yesterday afternoon trying to find my front rattle, I would like to share the culprit. Just finished getting this beauty going after a dozen years of neglect. On first test ride I heard a rattle that sure sounded like it was coming from caliper which I just rebuilt. Tried disc brake quiet, removed headlight, checked under tank, and even removed alternator cover thinking something was rattling around in there. It ended up being the aluminum plate held by 4 screws between forks just above fender was loose. Tightened up, rattle gone.
stevenrankin
Active member
thanks
Thanks for sharing the solution and welcome to the MOA airheads. LOL a simple fix. St.
Thanks for sharing the solution and welcome to the MOA airheads. LOL a simple fix. St.
