Pics of broken fork parts


16 replies to this topic
  • Bigcr

Posted May 19, 2008 - 04:39 PM

#1

It appears as if the rod that connects the inner chamber to the bottom of the fork pulled itself out somehow. When I replaced the springs, I followed the manual exactly.
Posted Image

You can see here that the nuts on the end have moved. They were exactly the same when I put them together. The inner rods are done too.
Posted Image

Notice the bushings half way up the inner chamber now, as well as the scratches.

Posted Image

What do ya'll think?

  • yzfjbw323

Posted May 19, 2008 - 06:42 PM

#2

When I was replacing fork seals this spring I had visions of this happening as I was putting everything back together. I feel I followed the manual step by step now I am a little worried.

  • grayracer513

Posted May 19, 2008 - 08:34 PM

#3

You only posted a closeup of one rod end, but here's what it looks like to me.

Before reassembling the inner cartridges to the outer assembly, you are supposed to verify that the adjuster lock nut is far enough down the rod that it exposes at least 19mm (3/4") of the threaded end of the damper rod. (see page 5-38) You also need to back the rebound clicker all the way out. At this point, the inners are inserted into the lower legs, and the spring compressed so that the rod extends through the bottom of the fork, where it is held with a tool. (page 5-39) The rebound adjuster is then screwed all the way down onto the rod until it bottoms out against it. Then, the lock nut is run up against the adjuster and tightened.

This does two things. First, it assures maximum thread contact or the rod within the adjuster assembly. Second, it establishes a repeatable distance between the adjuster clickers and the rebound valve up inside the cartridge, so that 8 clicks out will be the same as it was before the fork was worked on.

Judging by the aluminum in the last 4 rod threads, it looks to be as if this process was done incorrectly; that the adjuster was either not run all the way down the rod, or the nut was not tightened against it, and it backed out, then broke the threads.

  • Bigcr

Posted May 20, 2008 - 05:36 AM

#4

Grey, you're probably right. However, on page 5-39, step #28 it says there should be a .5-1mm gap between the adjuster and the locknut. Therefore, it would not be tight. That's were I messed up.

  • grayracer513

Posted May 20, 2008 - 05:48 AM

#5

The measurement of that gap is exceptionally confusing the way it is written. The reason for it is to establish that the adjuster is screwed down all the way onto the rod, and that the nut is not stopping it from doing that.

Notice that the following step calls for the lock nut to be tightened to 21 ft/lb.

This is not the only place the manual is difficult to understand, even in the fork section. Japanese is apparently a very hard language to translate from.

  • Kasjok

Posted May 20, 2008 - 05:54 AM

#6

So the point is to have no gap between? Why does manual recommend there to be 0.5 - 1mm gap then? Maybe I missed something, but I want to be sure as I am going to do my forks somewhere in this week.

  • grayracer513

Posted May 20, 2008 - 08:34 AM

#7

The point of checking for a gap is to make sure that the adjuster has been screwed all the way down on the rod until the end of the rod is bottomed against the adjuster, and that the lock nut is not stopping the adjuster from doing so.

Start by turning the lock nut as far down the rod as it will go. It should already be there just as a result of holding it while you unscrew the adjuster from the rod. Once the lock nut is loosened from the adjuster, you will then turn the adjuster about one turn and you will feel it come to a second tight spot. This is the point at which you have run the lock nut all the way down the thread, and you are now loosening the adjuster from the rod.

In assembling this, do two things first: Check for a minimum of 19mm of rod extending past the lock nut, and be sure to back the rebound clicker all the way out.

Put a shop towel or a clean flat board on the floor and stand the cartridge and spring on it, top down. Lower the outer tube assembly over the damper/spring. Slide the axle into the axle lug on the lower fork tube so you can use it as a handle to compress the fork spring.

If you do not have a rod holder tool like the one in step 27 on page 5-39, use a pair of pliers, not to grab and hold the rod (you don't want to scar it), but to allow the nut to sit on the sides of the jaws. Compress the lower fork leg until the damper rod extends far enough out of the bottom to engage the tool. If using pliers, gently close them around the rod, and let the fork back up until the lock nut bears on the sides of the jaws and stays there. You'll see what I mean.

Now, run the adjuster down until it stops. It should be free enough to be run all the way down by your fingers. Once you feel it come to a stop, you check the gap.

Here is what is significant about that gap. If there is no gap, that means the lock nut stopped the adjuster from bottoming out on the rod. If you verified that you had the 19mm+ of exposed thread to start with, and the gap is too big, that means the adjuster is not all the way down on the rod.

Once you have the adjuster all the way on, then tighten it (step 29) to 21 ft/lb.

Is that clearer?

  • Kasjok

Posted May 20, 2008 - 08:58 AM

#8

I think I got it. I thread the adjuster all the way in and turn locknut farther, if necessary. Then I will tighten the locknut up against the adjuster. OR is this final step unnecessary?

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  • grayracer513

Posted May 20, 2008 - 09:01 AM

#9

Tightening the lock nut against the adjuster (step 29) is CRITICAL.

  • Bigcr

Posted May 20, 2008 - 10:05 AM

#10

My next question is do suspension shops carry the parts to fit the inner cartridge or do I just need to order the whole thing for both legs? On Yamaha or Troy's and NCY' s parts fiche's I can't find just the rod part. $336.00 per side...Ouch!!

  • grayracer513

Posted May 20, 2008 - 10:07 AM

#11

Contact Dave Johnson at Smart Performance

He may be able to help.

  • Kasjok

Posted May 20, 2008 - 10:08 AM

#12

This is not the only place the manual is difficult to understand, even in the fork section. Japanese is apparently a very hard language to translate from.


Manuals should be translated in association with a mechanic(s). If they cause confusion for you, english speaking people, then you can imagine how " :thumbsup: " it must be for a foreigner like me.

  • grayracer513

Posted May 20, 2008 - 10:10 AM

#13

The fact that anyone can learn English as a second language is remarkable to me. I admire people like you for that. :thumbsup:

Just for Fun, meaning offense to no one:

http://www.engrish.com/

  • Kasjok

Posted May 20, 2008 - 10:54 AM

#14

Thanks, but we have to admit that english is more or less global language these days and speaking it is almost a must by default. If you speak english it means the "western world" is opened for you. I can`t imagine where I would be with my MX hobby with out all this knowledge circulating in english.

Here, in eastern europe, russian used to be a jack-of-all-trades language. Not hard to understand why...
But now that the new generation is taking over it less and less universal language. In Estonia we start learning our second foreign language in fifth or sixth grade (english in third). Many choose russian as their second language like I did, six years ago. And with these six years I pretty much can`t even make a sentence in russian, not to mention knowing the grammar rules. The reason why I and 95% other people born in late 80s to present day can`t almost speak russian is the lack of using it in real life. Allthough there are hundreds of thousands russians in Estonia we fight for our own language and independence. You might have heard about these issues we have with Russia and russians so that might be another reason for new generation not to be too keen on learning a foreign language of that kind. I am affraid I got a bit too political, but the I hope you can understand the bottom line. :thumbsup:

  • grayracer513

Posted May 20, 2008 - 11:13 AM

#15

I am affraid I got a bit too political, but the I hope you can understand the bottom line. :thumbsup:

It's off topic, but too few Americans have in their minds that freedom and independence are why this country exists. I admire you for that, as well.

  • Wiz636

Posted May 20, 2008 - 01:00 PM

#16

Allthough there are hundreds of thousands russians in Estonia we fight for our own language and independence. You might have heard about these issues we have with Russia and russians so that might be another reason for new generation not to be too keen on learning a foreign language of that kind. I am affraid I got a bit too political, but the I hope you can understand the bottom line. :rolleyes:


It's off topic, but too few Americans have in their minds that freedom and independence are why this country exists. I admire you for that, as well.


Word to that! :thumbsup:
(there's some slang for you)

  • Bigcr

Posted May 20, 2008 - 07:53 PM

#17

Contact Dave Johnson at Smart Performance

He may be able to help.


Thanks man, I spoke with him this afternoon. I'm sending it all off to him in the morning.:thumbsup:





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