Thread: K1 shocks topping out.

When I took my bike apart to rebuild it the front shocks were full of dirty oil so turned them upside down like the manual says and compressed them to get it all out. There was no reason for me to rebuild them because they worked fine and were not leaking. Since I have put my bike back together and filled them with the correct fork oil and quantity when the front wheel comes off the ground the shocks tops out. It's like there is no rebound dampening on the shock and it extends all the way. Any ideas?

I think im following you, but im only guessing. Since I am dealing with bad forks myself, here is what I know...


If you are talking about the fork leg binding up on the upper tubes called stanchions, this is caused by a few things I have found.
Since I have purchased TWO sets of bent/bad forks I know the symptoms well, or shall I say more than I wanted to lol

So first thing is check them, one side is usually bent, a quick check is to loosen the tree clamp, and the top bolts, and make sure you can spin the upper tubes freely, and the bottom "leg" is not kicking side to side/wobbling.

The other thing is rust and or rust pitting. If there is rust on the tube, the bushings catch and bind up. On the K1's the bushings are removable, but I never did find replacements, and any questions I have posted (here) go unanswered. So my guess is a slightly bent tube. If they do not seem bent, try re-indexing the tubes in the tree and see if that helps. This takes some trial and error. - The symptoms as I would describe them: Forks compress ok (with some resistence, not smooth) , but bind up near the bottom, and do not slide back up and bind, or rebound at all causing either a jerky front-end (as mine is right now as I wait for a straight replacement) or worse, a bottomed front end with no suspension at all.


Also I have not had any luck repairing a bent fork tube. It seems the bushings are a very tight fit, so any bend at all will show up as binding and not ride smooth. I straightened (attempted anyway) two bad sets, and they still ride like crap and are unusable IMO.

So try reindexing the tubes, or at least find out which side is binding by pulling the wheel off and testing each side. When you nail down which side, then try checking for a bend, or try turning the tube in the tree and see if you can get the bushings to free up. What you want is a smooth dampened front end that won't bottom or bind.

I have not found a source for new tubes for the K1's. So I have no advice there.. HTH
Derek

Thank you for the reply but my symptoms are not the same. There is no rust at all and the legs are not bent. They worked great before i took them off and drained the oil out. Is there a special way to put the oil back in besides just pouring it in the top? The manual just said to pour it in. The bike i'm referring to is in the general CT70 thread (Painting a CT70) where there are many pictures etc. Maybe i can explain it a little different. What is happening is when i do a wheelie and the front tire comes off the ground the shock extends all the way with no dampening and slams. If i just lift the front off the ground it is the same. I've tried to compare it to my other K1 and they look identical.

Here is a thought. Damping is obtained by forcing oil through small holes. You said that the fluid was really dirty. What if the holes are clogged and all the fluid is "trapped" on one side of the system. Possible explanation?? Next step would be to remove the seals and clean the inside assembly.

if you werent rebuilding or cleaning all the crap in the bottom of the forks,why did you remove em?i would have removed the drainplugs on the forkleg to replace the fork oil instead of removing the forks.seems like a waste of time.you may hve over filled them.remove the drainplugs 1 @ a time and push the fluid out and add 3 ozs in each leg.

Originally Posted by scooter

Here is a thought. Damping is obtained by forcing oil through small holes. You said that the fluid was really dirty. What if the holes are clogged and all the fluid is "trapped" on one side of the system. Possible explanation?? Next step would be to remove the seals and clean the inside assembly.

X2. I think this sounds likely. No way to fix or diagnose without disassembly. I don't see a solution aside from remove and replace, with proper cleaning and then new fork oil. A pain, but it should cure what ails ya.

Originally Posted by P.C.

if you werent rebuilding or cleaning all the crap in the bottom of the forks,why did you remove em?i would have removed the drainplugs on the forkleg to replace the fork oil instead of removing the forks.seems like a waste of time.you may hve over filled them.remove the drainplugs 1 @ a time and push the fluid out and add 3 ozs in each leg.

Maybe i haven't put enough in. I only put 3.4 tablespoons. A lot more than that came out. I don't have it in front of me but i thought i read something like 57cc.

I run 4ozs in each leg after a complete cleanout and rebuild,you will be surprised how much crap settles in the bottom of the legs.alot of heavily caked gunk.i would take them off again and thoroughly clean em.buy 2 seals even though yours arent leaking.remove the little snap ring over the seal. grab the assembly one hand on the upper and one on the lower,and give a couple real good pulls and they will come right apart.it's very easy to do.HTH.

Thanks guys.. I put the 4oz in and the shocks work great!! One day when i'm bored i will pull them apart and clean them out.

Thanks for posting the update,glad it worked out.definatly clean em out.follow my recomended method of removal.a coat hanger straightened out and a can brakleen to get in the bottom of the leg works great.