Front suspension advise

[Spins]

How long did you drain your forks! I didn’t allow them to sit over night. I assumed I did get everything out. Peace Sports specs list the capacity at 320ml. I’m might just try to add another 80 ml and see if this helps.

[Magician16]

Originally Posted by Spins

How long did you drain your forks! I didn’t allow them to sit over night. I assumed I did get everything out. Peace Sports specs list the capacity at 330ml. I’m might just try to add another 80 ml and see if this helps.

I actively pumped them about 20 times each. Every time I pumped them, I'd get some out. After a couple pumps I'd let them drain for a couple minutes. Probably less than an hour total drain time. I don't know how much you added, but Jasbeth's amount works well, less oil would equal more travel and/or bottoming out.

[Magician16]

Thumper, this is a video on all types of forks.
If you still have your wheel on, the weight of the wheel is holding the cartridge down. You should be able to pull the cap up easily.

[jasbeth]

Originally Posted by Spins

How long did you drain your forks! I didn’t allow them to sit over night. I assumed I did get everything out. Peace Sports specs list the capacity at 330ml. I’m might just try to add another 80 ml and see if this helps.

330ml is way too much, we ran numerous test on levels, travel and rebound on stock inverted shocks. We started at 330ml, and pulled out 5ml at a time until we found the best levels to keep for the action we wanted without bottoming out or feeling like there was no front suspension. 330ml and it will feel like you have no front shocks, stiff as hell. Again, the amounts listed work with all of the Chinese inverted shocks we have worked on. Riders weights ranged from 160-200lb's.

[Thumper]

Originally Posted by Magician16

Thumper, this is a video on all types of forks. (video)
If you still have your wheel on, the weight of the wheel is holding the cartridge down. You should be able to pull the cap up easily.

The wheel is on the ground, front end still fully assembled. I will have to take it apart when I do this.

So this is a cartridge style fork, I guess, with the cartridge connected to the cap? And I guess the spring DOES push directly against the cap and those threads bear the impact. Really? On Japanese bikes I've worked on (non-inverted forks), those threads are extensive and tight and the spring is in fact right up against the cap.

Have you modified the damping so that low impact has restriction but high impact is allowed to compress (I've seen the valve assembly mod on non-inverted forks on this forum)??

[Magician16]

Thumper, I used Jasbeth's method with no damping mods. If you pull your front axle, you will be able to pull the cap up to add more oil.

[Spins]

I removed 200ml and put back 200ml . I didn’t want to overfill them. I assumed I didn’t get everything out.

[grhanka]

If your forks are too soft, bumps will fling your butt into the air because the front end gets no lift. My 2021 TBR7 needed several more inches of spacer, so long it was difficult to get the screw caps started.

[Magician16]

Originally Posted by Spins

I removed 200ml and put back 200ml . I didn’t want to overfill them. I assumed I didn’t get everything out.

When I did my Magician, I put more oil in than I got out. I think it varies a lot, but if you didn't put at least 230 ml. in, you don't have enough for sure. Add 30 ml. to each side and check it out. If you still don't have enough travel, try another 20 or 30 ml.


I have never bottomed out either bike.

[Thumper]

I bottom out regularly on moderately deep holes like you might find in a road side drain going slowly. I don't think I have the right amount of oil in my fork.

I did find this excellent seal replacement video that shows the anatomy of a USD fork

[Spins]

Originally Posted by Magician16

When I did my Magician, I put more oil in than I got out. I think it varies a lot, but if you didn't put at least 230 ml. in, you don't have enough for sure. Add 30 ml. to each side and check it out. If you still don't have enough travel, try another 20 or 30 ml.


I have never bottomed out either bike.

I think I’m going to add another 40 ml and retest.

[Megadan]

Originally Posted by Thumper

I bottom out regularly on moderately deep holes like you might find in a road side drain going slowly. I don't think I have the right amount of oil in my fork.

I did find this excellent seal replacement video that shows the anatomy of a USD fork

The way most of these cheap USD forks are constructed is very different from a big brand fork made by Showa or Kayaba that is often found on most big brand bikes. They are much simpler and more akin to a standard damping rod fork that just got inverted.

The issue you are complaining about sounds like the low speed damping is too soft, which is often also an issue with standard damping rod forks and it has to do with the way the damping is executed. Oil flows freely through the holes in the damping rod at low speed, so there is very little damping available, and at high speed it can become harsh because the volume of oil can't flow fast enough through those fixed orifices. This is why I installed fork valves on my Hawks forks, to reverse this functionality so that they operate properly for the conditions required. Higher end cartridge forks like the ones in that video have valves and shim stacks that regulate flow to function the same as the valves I installed in my Hawks forks. That is why those valves are often called cartridge emulators.

[Thumper]

Originally Posted by Megadan

The way most of these cheap USD forks are constructed is very different from a big brand fork made by Showa or Kayaba that is often found on most big brand bikes. They are much simpler and more akin to a standard damping rod fork that just got inverted.

The issue you are complaining about sounds like the low speed damping is too soft, which is often also an issue with standard damping rod forks and it has to do with the way the damping is executed. Oil flows freely through the holes in the damping rod at low speed, so there is very little damping available, and at high speed it can become harsh because the volume of oil can't flow fast enough through those fixed orifices. This is why I installed fork valves on my Hawks forks, to reverse this functionality so that they operate properly for the conditions required. Higher end cartridge forks like the ones in that video have valves and shim stacks that regulate flow to function the same as the valves I installed in my Hawks forks. That is why those valves are often called cartridge emulators.

These bikes are famous for being clones with reverse engineered parts... It is surprising that they engineered something different, or even adapted the standard damping rod design to a USD fork. The cost of machining and parts for the dual reservoir USD design in the Showa that is on the Honda that is the target of cloning must be much higher!

On the other hand, the triple tree should be compatible with installing a used Showa. It seems like 37-38mm clamps are on the Storm. I will get the caliper out and check the diameter of the upper tube.

[Magician16]

A set of Showa forks cost more than I paid for my Storm. A used set from a CR250, I've seen for $500+.

[Thumper]

Those dual reservoir Showa style forks are completely different than the USD forks on the Storm. THESE VIDEOS do not apply, except for changing the fork oil. But that does not cover upgrading for advanced damping...

I just pushed the fork down, and it got pushed out (compressing the companion fork tube):




Someone posted on this forum an add-on valve modifier to standard shock damper for adding a simulation of the mild slow damping and stiffer fast damping that the more sophisticated Showa dual reservoir USD shocks are capable of. Having USD forks with standard damping rods is better since they are much stiffer than conventional forks, but damping rods can't address the extreme differences of a light impact and a severe impact.

It is the Racetech cartridge emulator that adds this capability(and maybe there are other similar options). This seems like the only way to really improve cheap USD fake cartridge USD shocks like the one on my Storm. I need to inspect the Storm USD inner diameter and maybe contact Racetech. They have many different models for different shocks. Here is the information on how it works:
https://racetech.com/page/title/Emul...%20They%20Work

I don't think that volume of fork oil is the right approach. Obviously, it is important to use the right volume to get the best performance from the standard damping rod style shock, but it doesn't fix the slow dive problem! It really seems worth it to add the cartridge emulators if possible. They separate light damping (a pilot circuit) from main impact damping which has essentially infinite valve preload adjustment.