My EX30 Suspension System Experiments

[n2eus]

This is a summary of my experiments with combinations of suspension system components, the corresponding results, and my opinions.

 

My aim: to find the optimal system for my use case.  I am a 150 lbs rider weighing about 168 AGU.  My EX30 is used exclusively for street riding.  I prefer a comfortable smooth ride.

 

1.       The stock shock was the first that I tried.  This shock was initially adequate, until the air leaked out within approximately 100 miles.

 

2.       The second shock I tried was a JFOYH Coil+Oil Shock Absorber Adjustable Damping with 1000 lbs/in spring.  Fitting this shock required grinding off the shoulders a little.  Performance of this shock was more tuned for my riding than the stock shock was.  Just a little stiffer than I prefer.

 

3.       The third shock I tried was a DNM Damping 2 System Mountain Bike Rear Shock Rebound/Preload Anodized Aluminum Alloy 6061 with 750 lbs/in spring.  Unlike the previous shock, it didn't require any grinding to fit it.  I just added a little preload, to lower the sag to 30%.  This resulted in the most comfortable suspension so far.

 

4.       The fourth system I tried was a Begode DS200-55A Suspension Kit, combined with a 900 lbs/in spring designed for an Extreme, including the new blue linkages.  Thanks, to @Jason McNeil at eWheels, for donating the 900 lbs spring "in the service of science".  This spring doesn't directly fit the DS200, because the free length is 135 mm (5 mm longer than the 1300 lbs spring that is included in the kit).  To accommodate the extra length without a spring compressor, I ground off 5 mm of material from the conical side of the preload collar, as shown below:

Note:  Another option, which doesn’t require grinding, is replace the preload collar with a Fox Shox Rear Shock Spring Collar/Retainer 234-00-099.

The air chamber of the DS200 occupies the space where the bar, connecting the metal brackets, normally resides above the tail light.  Therefore, drilling of new holes was required, in order to lower the bar and allow shock space (shown below).

The new linkages have two holes for the top rear pin, to enable selection of hard or soft response as desired.  I initially chose the lower holes, which correspond to softer response.

 

Another modification I did was added 3D printed spacers on the rear pins (2.2 mm for the top pin and 2.8 mm for the bottom pin) to eliminate the rattling of the linkages due to inaccurate design dimensions.

With the shock installed in the lower holes (for soft response), the initial sag was beyond excessive.  The weight of just the battery boxes made it sag 50% without rider, so I didn’t bother with preload adjustment until after I moved the shock to the upper holes (for harder response.)  I then added 8 mm compression with the preload collar, for 27% sag.

Now that I’ve tested the Begode DS200-55A in this configuration, over various sized bumps, and at various speeds, with 100 psig in the air chamber and both damping adjustments tuned, I love riding my EX30 more than ever!

Conclusions: 

For me, the smoothest and most luxurious experience came with the modified DS210-55A shock combined with the 900 lbs spring.  I’m impressed with the increased quality from Begode suspension designs, since the original EX suspension.

Now that I’ve received another spring I ordered, my recommendation to other 150 lbs EX30 riders who want a smooth street suspension, is the following configuration:

Begode DS200-55A combined with Fox Steel Rear Spring 039-03-101 - 800 Lbs/in, 2.300 Travel.  This 800 lbs spring and the 1300 lbs spring have identical dimensions (except wire diameter).  Therefore, it will fit a DS200-55A without requiring grinding of the preload ring.  I still recommend the added spacers to eliminate the slop in the linkages.

For a less expensive option, the DNM Damping 2 System Mountain Bike Rear Shock Rebound/Preload Anodized Aluminum Alloy 6061 with 750 lbs/in spring is almost as smooth.

Edited October 15 by n2eus
clarification

[Julianjc84]

Fantastic you found a solution.

If you are keen to do more experiments take a look here

 

[n2eus]

1 hour ago, Julianjc84 said:

Fantastic you found a solution.

If you are keen to do more experiments take a look here

 

Thanks for this amazing tool.  Someone with CNC machine would probably enjoy this.

I have no interest in doing further experiments now that I can ride again and again.

[InMoOnGoWa75012]

[START off topic]

Last months, during summer, I found out "WD-40 Multifunctional Product Classic" is magic when used on the moving parts of the EX30 !
Before was using my EX30 with a noisy and creaky suspension ! with correct usage of WD40, suspension is really smooth

[END off topic]