Atomik Nitrous Forks Slow Rebound

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i made my own soft jaws by cutting up an old tyre, works a treat and deffinately doesn't leave any marks. I did get both the key and the foot loose (think that used to be a song :)) but both just free spin....
 
Unfortunately for me it wasn't as easy as rumple said.... Maybe try the rattle gun first on the inside on the fork foot, maybe it might come off then...

Try a bit of heat on it. Warm to the touch, might have some loctite on it.

Memory is a bit hazy, but i think the bottom part pushes against a washer and rubber seal. the allen key goes through the washer and seal and screws into the insert (compression and rebound tube).

The pic may be wrong and i may have wasted the 5 minutes it took me to do it, but, i believe its right.

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Blue is the fork leg, black is the axle holder, maroon is the rubber seal.


If i didnt have a busted wrist id pull my fork apart and tell you 100% :(


Matty, any luck with pics, am i on the right track???
 
I rode enduro mate a long time ago on an IT 490 Yamaha. Rebound was controlled by the spring action and fork oil grade.Compression is the spring and to a lower evil the oil. Compression is the big hit when you land(the spring rate and he oil does not do much on compression) and the oil does try to take a bit away from it,but rebound is the softly softly approach back up again from the spring and the oil. The chinese springs are Kraft cheedar cheese quality. My young bloke has an Atomik 70 and it has sagged in the front and the same problem you are looking at. I put 2 3mm washers on the top of the springs to bring them up to stiffen them and it is great. Running 15 wt oil. I must say though that the son and daughter are jumping this bike and flogging it. And nothing broken yet on it. When i do find what springs are compatible in the front I will upgrade them but no one seems to know atm.I am open to anyone to differ from my views and whinge I am wrong. I just know this worked for me.
 
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Old thread.. but finally got around to having a good look at these china forks... and figured it out.

OK. Slow rebound problem fixed.

You need to strip down the forks as mentioned earlier in this thread.

TO remove bottom of fork leg (the Shoe), on the bottom of the chrome leg that is, you will need to place leg in soft jawed vice.
Inside the fork leg is the plunger unit, which is a sealed unit. just like a piston and barrel type setup...
Wedge a flat screwdriver in between the inside of the fork leg and the plunger unit to stop it from spinning. See image 1
Now when you undo the allen key at the bottom of the fork leg, the inner unit is held firm, and you can undo the allen bolt. May be a bit firm to undo, as it has locktite on the thread.

Once plunger unit is out, you will see two holes in the tube. Bottom hole is larger (image 2), and controls compression speed. this hole is fine.
The top hole is VERY small (image 3) and controls rebound speed. It is so small and bit or gunk, plastic, or rubber from deteriorating seals or something can clog it up... then no oil can get out or the hole... and thats why there is no, or very slow rebound.
Drill this hole out to be bigger... not too big, but just 1mm or 2mm bigger.

Now reverse steps and put it all back together....

Doing this job, the hardest part is not spilling the oil...good luck!!

PS. Image 3 is after I drilled the hole larger... it was pretty tiny before..... like a pin head i recon....
 

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Yeah, these are the original forks off the nitrous... have a look at image 1... you need to do this to stop it from spinning while you undo the allen bolt inside the shoe...

TO remove bottom of fork leg (the Shoe), on the bottom of the chrome leg that is, you will need to place leg in soft jawed vice.
Inside the fork leg is the plunger unit, which is a sealed unit. just like a piston and barrel type setup...
Wedge a flat screwdriver in between the inside of the fork leg and the plunger unit to stop it from spinning. See image 1
Now when you undo the allen key at the bottom of the fork leg, the inner unit is held firm, and you can undo the allen bolt. May be a bit firm to undo, as it has locktite on the thread.
 
Ah hah.... yep i see it now. not that i need to do anything with cause i now have the hornets fitted. When i'm next bored at home i might give it a try. Thinking about it i might have a go with the rattle gun first and see if it does it. Cheers for the info :) P.S. Hows the injuries?
 

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