Author Topic: Fork clanky noise-- normal or problem? (Read 5236 times)

Popwood · « **on:** March 17, 2009, 05:16:31 PM »

I've heard this sound coming from the forks before, but today it got me to worrying. Here's the deal. Sitting on bike, front brake locked, push down on forks and compress springs then release. As often as not there's a "clank" when the suspension springs back. If I press/release, press/release, as often as not will "clank" when springing back to normal position.

While riding, fast or slow, there's no noticeable issues. So is this normal, a problem, and if a problem, what's the remedy. Also, if it is a problem, is it unsafe to ride with this condition?

By the way, it's a '75 550K with 8,000 miles and I changed the fork oil last summer. Have had the bike less than a year and I'd swear the fork oil had probably never been changed before.

LoopsAndLogic · « **Reply #1 on:** March 17, 2009, 05:55:14 PM »

I have the same problem when going over bumps....

I too would be interested in finding out what this problem is....

-LL

Steve F · « **Reply #2 on:** March 17, 2009, 06:05:33 PM »

Check the caliper mount for looseness (if there is such a word). The bushing that the caliper mount swings on can get elongated, and they rattle. New bushings, pressed in and reamed to size to fit the pin.

Popwood · « **Reply #3 on:** March 17, 2009, 06:21:11 PM »

Steve F: Checked the caliper mount and it's rock solid. This sound for me isn't a rattle, it's clearly two objects that bang together when the springs release and return to normal position. Each spring compression release gets one clank.

Steve F · « **Reply #4 on:** March 17, 2009, 06:27:33 PM »

Then the next thing is check the steering head bearings and adjust if necessary. If that clears things up, I would recommend disassembly of the steering head, a good cleaning, greasing and reassembly. OR, go with some tapered bearings in there if you haven't already.
Another thing about the calipers is pull them up and down, not just wiggle them, to see if you hear anything there. Maybe the brake pads are loose in the caliper (?) just guessing there.

Popwood · « **Reply #5 on:** March 17, 2009, 06:39:53 PM »

OK, I'll look into the steering head bearings. Any thoughts on safety? Like I said, there are no issues while riding, but bearing down that hard on the front suspension in a quick stop isn't something I'd experience routinely-- if ever I hope!

WFO · « **Reply #6 on:** March 17, 2009, 06:47:34 PM »

I had an old dirt bike do that it ended up being most of the oil had leaked out and without any dampening it slammed back so you may check the levels even though you just changed it.

Steve F · « **Reply #7 on:** March 17, 2009, 06:53:53 PM »

If you still have the stock ball bearings in the steering, my bet is the races have dents, the balls have flat spots and maybe the races are cracked too. Raise the front tire off the ground to get the weight off the front end, and check side-to-side movement for any notchiness where the steering likes to settle in for no apparent reason. This could tell you if the races are damaged. Grab the front tire and try to jiggle the forks front to back checking for play in both the steering and the forks. Don't rule out problems with the wheel bearings either.

Popwood · « **Reply #8 on:** March 17, 2009, 07:20:00 PM »

Now I know at least one thing I'll be doing this weekend. Thanks, Steve F.

I've read several posts over the past months about the advantages of tapered bearings. If my stock bearings need replacing, I'll be looking at that as an upgrade.

bender01 · « **Reply #9 on:** March 18, 2009, 04:56:57 AM »

This ones way out there but what about a loose chain coming back down on the centerstand? I have a hard time pinpointing where noises come from. Thats easy to check.

Popwood · « **Reply #10 on:** March 18, 2009, 06:19:21 AM »

Thanks, Bender, but just did the chain adjust last weekend.

LoopsAndLogic · « **Reply #11 on:** March 18, 2009, 10:50:58 AM »

Mine too makes a clunk noise when it's coming back up after rolling over a bump or having the brake on and rocking the bike
back and forth.

Steering stem bearings are tight and smooth, and I did the test on the center stand as well.

Could there be a missing piece in the front forks that I forgot to put in? It has new seals and new fluid.

I was thinking maybe it's our fork leg bolts that are under the axles. They hold the fork shafts from coming out....

Maybe there loose... It almost feels as though there being restricted and then clunking loose to spring back...

It might be the Dextrol fluid is too think...

Sorry for the Hijack thread Popwood...

I better start a new thread

Duke McDukiedook · « **Reply #12 on:** March 18, 2009, 11:58:40 AM »

Mine makes that clunking noise when I first sit down on the bike.
It also has very little fluid in it due to PO sticking a piece of pop can down there to probably try and stop it from leaking! It wore a groove in the fork pipe so I have to replace the fork tube (got a used one off a K5) along with rebuilding my front brake (getting a little sticky lately).
Ah yes, where would we be without the PO's futile, cheap fixes?

Popwood · « **Reply #13 on:** March 18, 2009, 02:35:55 PM »

L&L, didn't feel like a hijack to me. I'd still like to know what's going on in there. I have no fluid leaking and no pop cans in there either. This is an easy test for other 550 owners and then we'd know if it's just the way it was manufactured or an issue worthy of concern. Let's hear from some others!! Get on the bike, lock the front brake, compress the spings and let the suspension come back to normal on its own. Clank or no clank?

LoopsAndLogic · « **Reply #14 on:** March 19, 2009, 07:20:43 AM »

Me too....

I'm going to start off by putting some high quality fork oil in, instead of using Dextrol oil like the OEM shop manual says.

I'll post back by Saturday with the results.

Lets get this figured out Popwood. Cause I know my bushings and stuff are tight.

Cheers

LL

Popwood · « **Reply #15 on:** March 19, 2009, 05:41:48 PM »

Let us know what you find with the oil change. I did the steering bearings check as suggested by Steve F and no problems there for me.

Look forward to your report back.

Bill Vaughan · « **Reply #16 on:** March 19, 2009, 05:50:54 PM »

Quote from: Popwood on March 18, 2009, 02:35:55 PM

L&L, didn't feel like a hijack to me. I'd still like to know what's going on in there. I have no fluid leaking and no pop cans in there either. This is an easy test for other 550 owners and then we'd know if it's just the way it was manufactured or an issue worthy of concern. Let's hear from some others!! Get on the bike, lock the front brake, compress the springs and let the suspension come back to normal on its own. Clank or no clank?

Have a '75 CB550 in the shop now. Got on it, rolled a little and locked up the front brake - no noise. Did it several times with the same result. Of course the entire bike was just rebuilt, so maybe that has something to do with it.

super pasty white guy · « **Reply #17 on:** March 19, 2009, 06:26:58 PM »

Well, I have the exact same clank. Pretty sure that mine's the caliper bushing though.

spwg

LBM 550F · « **Reply #18 on:** March 19, 2009, 06:38:35 PM »

Hi, I'am a newbie to sohc hondas but had that same noise in my 75 550F. I was sure it was in the forks (my caliper bracket and pivot is in great shape and well greased) pulled the forks apart and found nothing wrong other than way out of wack oil levels, another story. Anyway the noise turned out to be from the brake pads in the caliper. As you say,bounce the front end with the brakes held tight and loud rattle. Moved the bike up to the wall in my garage and use the wall as you did your brakes, push without using the front brake and no noise however hard I would push. removed the pads, they are oddly shaped on the backing plates, greese that hump section, make sure that washer is correctly installed and I used a very small dab of regular silicone sealant in 2 places and pushed the pads into it and rocked them to spead it out. Just a little worked and my wheel now turns free and the pad does not make that clank sound. Hope this helps.
Learned a lot from this site, thanks guys and gals. L.

cb350twin · « **Reply #19 on:** March 19, 2009, 06:49:30 PM »

My 750 has made the noise for a while now ever since I changed the fork oil. So I always thought it was the forks. So today after reading this thread I was was determined to find out the cause as I have tried other times and failed. I started by tighting ever bolt/nut on the front end. Found out one of my wheel holding nuts was loose on the fork.

Still made the clank / popping noise. So Then I grabbed ever single part I could find and shook it violently. Caliper... BINGO! Losened the nut on the adjuster bolt. tighten the bolt with the notch and no more nose!

Moral of the story? Get pissed and show who's boss.

Popwood · « **Reply #20 on:** March 22, 2009, 05:38:05 PM »

LMB 550F,

Great bit of analysis there. I'm going to try the test using the wall rather than the break and see what I get. Just could be the break pads. I replaced mine less than a year ago, but I still get a bit of rub on the pad when I free spin the front wheel.

You may be learning a lot from the forum-- I think we all are-- but your contribution is adding to the collective knowledge. Thanks!

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Author Topic: Fork clanky noise-- normal or problem? (Read 5236 times)