Clonk when braking
 

Hi all, I have a 94 f2 and when braking there is a single clonk from the front, it feels like the handle bars so I am thinking the head bearings need attention. However when reading up on head bearings all the information seems to point towards roughness when turning and this is not my issue.

I have recently replaced the brake lines and pads and do not recall having this issue before then although this could just be coincidence.

It only happens under normal or hard braking, not light.

I wonder if its the pads moving in the calipers and the clonk is felt up top but cannot see any issues here

Any of you fine people got any tips for tracing this issue please?

I would check all the braking components for loose bolts, caliper bolts, rotor bolts, pad pins. Maybe the steering stem bearings need re-torqued. Maybe the front fender is loose or broke.

Almost for sure it's the head bearings. Probably just need to be tightened.
If they are too loose, you'll get a clonk under heavy braking.
If they are too tight, you get roughness when turning the bars (or a weave at low speeds).

Checked all brakes and all good, it seems to be the forks bottoming out and there is now a creaking noise again when braking. Looks like a fork rebuild, is that a diy job or specialist?

Fork rebuild is for sure a DIY. Get yourself a Clymer or Haynes manual. The manual will tell you that you need a "fork seal driver". But Ive done it without the special tool. I made a homemade tool from pvc plumbing pipe. Also you can make a fork oil level tool from a big scringe or turkey baster. It also helps to loosen certain bolts before removing the forks, the triple clamps are like extra hands in this situation. I also used a steering damper clamp, clamped to my work bench to hold the fork vertical. It helps when getting the oil level right and putting the cap back on. You cant put the cap on while pushing down on the fork with the fork on the ground. That where the steering damper clamp helps, by holding the fork by the upper tube.

This is definitely a DIY job. Watch my video here:

After you've seen how easy it is and how few tools you'll need, you'll be ready to tackle the job.

Note that even though I did this on forks from an '84 VF750F, yours are very similar. I've rebuilt both, so I know from personal experience that there are no major differences.


Best of luck and let us know how you do.


Tom

94 forks are a little different, the cap wont come off, right off the bat. You''ll have to compress the spring, lock plier it down to get to the nut that needs loosened, so the cap can be completely removed. But Yeh it still a DIY job for sure.

I'd love to be able to do my own forks. I typically have someone do them since I became somewhat a suspension snob. I'll be sure to watch your video. Thanks.

Thanks Tom. I enjoyed that and it seemed super easy (with the right tools). Do you have any videos showing the concave vs convex sides of the washer and also of one where you removed the valving? Any of you checking the oil height?

When I had OCD I did forks annually but my OCD is in remission. Don't laugh, I used to do brake pads at about 3-4 week intervals, bleeding and refreshing fluid at 2x that rate.

Glad you enjoyed my video. I have 6 others, but none that cover the specifics you asked about. The washer always (as far as I know) always goes in with the concave (cupped) side facing up. As far as the oil level goes, the older bikes I work on specify the number of CC's of fork oil to add. The video was meant to be generic since the technique is the same for many forks, so I didn't get into refilling the oil level.


Glad to hear that your OCD is in remission!


Tom