Choosing the right suspension setup (on Begode Master)

[Panzer04]

I'm in search of a good suspension setup for my Begode Master. I'm wondering how people have been setting up and tuning their suspension EUCs in general, though.

My current setup is a 1250lb spring, S linkage, 20mm sag (out of 70mm available travel), as near 0% preload as possible (as it should be for a coil shock :)). I think I probably want a yet stiffer spring, in the 1500-2000lb range.

This is ~28% sag, which is probably about right for comfy street riding. I bottom out if I also push down on smaller drops, and if i'm not careful on ~0.5m drops. The required forces to handle bigger drops gets pretty excessive quite fast with the limited suspension travel, unfortunately, so I'm not sure if I should up the spring strength too much more or not. (ie. 1500 vs 2000lb, from my current 1250lb)

I'd like to run MTB trails, often with a fair few jumps and drops (nothing too massive, currently :p) I think my current shock is likely just a bit too soft for trail riding with features, but it would be interesting to get some perspective. I think there's a huge variation in what people think "good" suspension should feel like and how to set it up - eg. Leaperkim wheels are generally perceived quite well, yet people are often using fairly substantial preloads to achieve reasonable sag, which IMO means the spring is too soft - but this is probably fine so long as you don't do anything more adventurous than benign grassy fields?

I've a couple of questions for other riders here:
- How much sag do you run (with a coil shock, ideally) on your wheel, and what coil weight? Do you preload?

- How much of a drop do you accept before you bottom out? Perhaps for those of us with 130mm suspension S22s and Extremes this is much less of a tradeoff than for the 70mm master (almost 2x the suspension travel goes a long way..)

- What kind of riding are you setting up for? Trail, street, jumps etc.

 

 

Edited January 31 by UniVehje

[Rawnei]

The problem is the linkage, even the s linkage is not great unfortunately, either get a 3rd party linkage or increase the dampening.

Then it's the issue of 70mm travel which isn't a whole lot, there's just a lot of limitations overall to make it a great feeling all-round suspension wheel.

If I were you I would run as is and then upgrade wheel in the future to something with better suspension instead of investing too much more money trying to make the master suspension good.

On my wheels they are setup to handle anything and feel good in all scenarios, I could not achieve this on my master that I sold long ago even with 3rd party linkage and rockshox shock.

Edited January 31 by Rawnei

[Whalesmash]

I spent a lot of time trying to get the master's stock geometry to work better, but at the end of the day, I ran into the limitation of 70-75mm of travel just not being sufficient. In it's stock form, running 20% sag leaves you with so little travel that everything feels harsh or just bottoming out all the time. Even with a proper progressive linkage, the ramp up has to occur so quickly that it ends up feeling harsh again. I think with the stock (or stock+) linkages, the best option I had was an air shock with a large volume spacer or extra oil/thicker oil. I usually ran the air shock under higher pressure so the suspension rode with very little sag just to get more use out of the compression stroke. This of course caused a lot of annoying top outs, but for the other trade offs available, it was the one I could live with.

At the end of the day I ended up modifying my master to have 100mm travel using ex30 slider bars. This, along with my own scissor style linkage let me get a proper 20% sag that still left me with 80mm of available compression, as well as giving me a proper progression through the stroke. Kind of sucks that you have to do such a significant modification to get the desired performance, but at least there are kits out there now. If you're looking for something similar, Loc Vo (facebook) sells a kit for ~$400 that will increase the travel of the suspension from 70/80mm to 110mm. I haven't bought that kit, but it looks to accomplish the same thing as my own personal design. HouNingNing also sells a 130mm travel kit, but it's almost double the price and has some teething issues that he needs to work out. 

[UniVehje]

As this is a model specific question, I moved this thread to better section and updated the topic so that others find this discussion also.

[Panzer04]

On 2/1/2024 at 4:32 AM, Whalesmash said:

I spent a lot of time trying to get the master's stock geometry to work better, but at the end of the day, I ran into the limitation of 70-75mm of travel just not being sufficient. In it's stock form, running 20% sag leaves you with so little travel that everything feels harsh or just bottoming out all the time. Even with a proper progressive linkage, the ramp up has to occur so quickly that it ends up feeling harsh again. I think with the stock (or stock+) linkages, the best option I had was an air shock with a large volume spacer or extra oil/thicker oil. I usually ran the air shock under higher pressure so the suspension rode with very little sag just to get more use out of the compression stroke. This of course caused a lot of annoying top outs, but for the other trade offs available, it was the one I could live with.

At the end of the day I ended up modifying my master to have 100mm travel using ex30 slider bars. This, along with my own scissor style linkage let me get a proper 20% sag that still left me with 80mm of available compression, as well as giving me a proper progression through the stroke. Kind of sucks that you have to do such a significant modification to get the desired performance, but at least there are kits out there now. If you're looking for something similar, Loc Vo (facebook) sells a kit for ~$400 that will increase the travel of the suspension from 70/80mm to 110mm. I haven't bought that kit, but it looks to accomplish the same thing as my own personal design. HouNingNing also sells a 130mm travel kit, but it's almost double the price and has some teething issues that he needs to work out. 

Thanks for detailing your experience - I've definitely considered modifying the suspension travel to match the EX30 (it's a big shame the master doesn't come with that stock - it seems like a much better middle ground than the ~75mm effective it comes with). Did you have any issues with making spacers for the battery mounts or the battery wire length? I do wish people charged a bit less for these kits, maybe there wouldn't be half a dozen alternatives if they priced them a bit more competitively lol ;(

Conveniently the s linkage is actually designed for 100mm travel, so If I full diy no additional parts are required, and the stats I've seen make it look like a pretty solid setup with OK progression.

On 2/1/2024 at 3:55 AM, Rawnei said:

The problem is the linkage, even the s linkage is not great unfortunately, either get a 3rd party linkage or increase the dampening.

Then it's the issue of 70mm travel which isn't a whole lot, there's just a lot of limitations overall to make it a great feeling all-round suspension wheel.

If I were you I would run as is and then upgrade wheel in the future to something with better suspension instead of investing too much more money trying to make the master suspension good.

On my wheels they are setup to handle anything and feel good in all scenarios, I could not achieve this on my master that I sold long ago even with 3rd party linkage and rockshox shock.

I'm not sure I agree. S linkage with coil shock is actually quite competent in my experience, thought it's pretty crap with air because of preload problems.

Short travel is definitely the main problem with the master suspension, if it were a bit longer stock (100mm like ex30 or 110 like loc vos kit) it would be much better, but that isn't what we've got sadly.

[Rawnei]

4 hours ago, Panzer04 said:

I'm not sure I agree. S linkage with coil shock is actually quite competent in my experience, thought it's pretty crap with air because of preload problems.

I'm referring to this:

Is this not the linkage you have?

 

[Panzer04]

13 minutes ago, Rawnei said:

I'm referring to this:

Is this not the linkage you have?

 

It is, though I don't currently agree with Julian's conclusions, though I love his work on characterizing the suspension. I think the travel ratios are reasonable, and you can make sure it's not preloaded by unwinding the coil shock. 2.5-2 travel ratio is much better than the original 3.3 or whatever it was on the original shock. I don't think the weird movement really matters. Ideally 100mm travel like the EX30 would take full advantage of the shock with more progression and more travel full-stop, though.

I guess I was more curious about the tradeoff between plush suspension and bottom-out resistance, though it seems like that might just not be possible with the limited travel on the stock Master if I want to do stuff like jumps with it.

 

Edited February 2 by Panzer04

[Julianjc84]

100% agree,
71mm vertical travel on the master sucks. Its just enough for road use.
25% sag on 71mm is 71/100*25= 18mm
71-18 = 53mm vertical stanchion travel.
Soon as you do a kerb or stairs and you will bottom out, and if you are not bottoming out with a high LBS coil or PSI its going to feel like a non Suspension wheel and that just sucks.

Currently i'm running a custom X linkage at a ~1.35:1 ratio with a DNM rcp2s rockshox 400LBS coil for my weight. Its nice. I can bottom it out but its a compromise.

RockShox make coils in 50lbs increments and are the cheapest. Can easy interchange to 300/350/400/450/500/550lbs for a 72kg naked rider.


I have new linkages at the laser cutters for a 210mm DNM and the LocVo style 110mm vertical travel stanchions that are 3mm tube custom made.
A video will be released when I get it done over the next 2 weeks.

i have all the Movement data and ratios in CAD so its very easy to simulate.
A big issues with the BEGODEs Frame issues is the linkage lengths that mount to the frame Top headder and lower H Bar. Should be Equal in length. but compromises have to be made else they collide with the seat, you can see in my above photo I have added risers. That's why everyone makes uneven length linkages to prevent collision with the seat & light and to keep the linkages tucked in closes to the tire.
This in turn makes for a not so smooth linkage movement curve but does not seem to effect the movement ratios and ratio curve and it only really impacts the last 10mm of movement.

 

Edited February 2 by Julianjc84
photos

[Panzer04]

1 hour ago, Julianjc84 said:

100% agree,
71mm vertical travel on the master sucks. Its just enough for road use.
25% sag on 71mm is 71/100*25= 18mm
71-18 = 53mm vertical stanchion travel.
Soon as you do a kerb or stairs and you will bottom out, and if you are not bottoming out with a high LBS coil or PSI its going to feel like a non Suspension wheel and that just sucks.

Currently i'm running a custom X linkage at a ~1.35:1 ratio with a DNM rcp2s rockshox 400LBS coil for my weight. Its nice. I can bottom it out but its a compromise.

RockShox make coils in 50lbs increments and are the cheapest. Can easy interchange to 300/350/400/450/500/550lbs for a 72kg naked rider.


I have new linkages at the laser cutters for a 210mm DNM and the LocVo style 110mm vertical travel stanchions that are 3mm tube custom made.
A video will be released when I get it done over the next 2 weeks.

i have all the Movement data and ratios in CAD so its very easy to simulate.
A big issues with the BEGODEs Frame issues is the linkage lengths that mount to the frame Top headder and lower H Bar. Should be Equal in length. but compromises have to be made else they collide with the seat, you can see in my above photo I have added risers. That's why everyone makes uneven length linkages to prevent collision with the seat & light and to keep the linkages tucked in closes to the tire.
This in turn makes for a not so smooth linkage movement curve but does not seem to effect the movement ratios and ratio curve and it only really impacts the last 10mm of movement.

 

ooh, interesting. Look forward to seeing it :). Where did you find 30mm tubing to replace the stock stuff? I've been looking at Ali and considering a mod, although it may be simpler to do as @Whalemash and get EX30 tubes instead. Don't forget you'll need brackets for the batteries (I'm sure you're aware anyway)

After riding it for a week I've been pretty happy with a 1250lb coil in the stock linkage, which seems like it corresponds to a ~600lb coil in your setup (assuming roughly twice the average ratio). On the stiffer side, not super plush, but it's active and works pretty well while only bottoming out on "real" obstacles. I guess if I had 100mm suspension I could either keep it the same but have more resistance to bottom-out or soften it up to 1000lb to make it a bit plusher.
 

[Whalesmash]

15 hours ago, Panzer04 said:

Thanks for detailing your experience - I've definitely considered modifying the suspension travel to match the EX30 (it's a big shame the master doesn't come with that stock - it seems like a much better middle ground than the ~75mm effective it comes with). Did you have any issues with making spacers for the battery mounts or the battery wire length? I do wish people charged a bit less for these kits, maybe there wouldn't be half a dozen alternatives if they priced them a bit more competitively lol 

Unfortunately doing the EX30 drive tube mod is not straight forward at all. The way I went about it, I recut the lower battery mounts out of aluminum plates such that they lifted the packs by the additional 20mm to match the increase in the height of the tubes. This kept the tops of the battery packs at their stock position against the motherboard tray and gave me more ground clearance (which was one of my goals for the project). I talk about it at around the 4:40 mark on the vid below. It's a little bit outdated since i broke some stuff on the wheel and had to revise my approach. If more clearance and higher pedal height are not goals, then it would be easier to just use the stock battery mounts + pedal hangers and just increase the tube lengths with your own DIY cut/drilled 30mm tubes. IIRC when I was looking for options, I found some compatible tubes on aliexpress or amazon for somewhere in the range of $30 for a pair. The size should be 30mm diameter with a wall thickness of 1.5mm or 2mm. I think stock was 1.5mm thickness, but I might not be remembering that correctly. Going thicker would just add more durability at the expense of cutting/drilling difficulty and maybe a tiny increase in weight. You could then either use a strong 3d printed 20mm riser above or below the battery to get the mounting points to line up. I do know a guy who 3d printed some spacers like this out of ASA with no issues.