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-   -   Revisiting Rear Suspension (http://www.chinariders.net/showthread.php?t=15958)

detours 08-05-2016 10:57 PM

Quote:

Originally Posted by jbfla (Post 227410)
detours,

I couldn't find the lighter spring on the CSC website.

How much $$$ is the new spring?

Thanks.

jb

Ryan told me about it. He says it runs $79.95. It you order a new shock, I'm sure you can specify it at no extra charge.

jbfla 08-06-2016 12:32 AM

Quote:

Originally Posted by detours (Post 227422)
Ryan told me about it. He says it runs $79.95. It you order a new shock, I'm sure you can specify it at no extra charge.

Thank you.

I already have the Progressive shock with the 400/450 spring installed.

On road it's fine. Fire roads it's still pretty harsh.

One last try to smooth out the ride before I give up.

jb

madsocial 08-06-2016 08:19 AM

The progressive shocks do require rebuilds. I wish they had used Legend Suspension as a better option shock. Their shocks are maintenance free and they guarantee them much longer. I think overall if Legend made one, it would be more worth the money to invest there than spending money on Progressive. Progressive shocks are usually stiff, due to them being a more performance/race based type of company. Legend is designed more around comfort for the rider.

I'll stick to the stock shock for now.

3banger 08-06-2016 10:30 AM

1 Attachment(s)
I have had the Progressive shock for about 4 months now and I per my usual approach; can't leave well enough alone. Here are the modifications I've made. If you notice the bottoming out bumper is almost half of the available stroke and I believe it makes the shock fell unnecessarily harsh. I trimmed mine per the include photos. The linkage rate on the RX3 is very non linear. Zongshen knows that in many markets the bike will get heavily overloaded and built a linkage rate to cope with this. The effect the additional spring rate of the rather stiff foam bottom out bumper is a pretty harsh feeling every time the suspension travel engages it. I feel the suspension has preformed well on some pretty rough trail since I made this mod. Also one of the other off road techniques I've been using is reducing the tire pressure for rides like the Alpine Loop and Imogene Pass. I've installed the guts of a 12 volt air compressor in the right side case.

3banger 08-06-2016 10:32 AM

1 Attachment(s)
Here is the shock with trimmed bumper.

3banger 08-06-2016 10:33 AM

1 Attachment(s)
On board air compressor.

Juanro 08-06-2016 11:43 AM

3banger, so you are saying that the shock has a longer travel but is limited by that foam bumper?

3banger 08-06-2016 01:08 PM

I know if the Progressive shock actually has more travel then the stock but yes I believe the foam pumber is making the shock excessively harsh.

BlackBike 08-06-2016 03:18 PM

Sooooo, now that you have the compressor, what about the air adjustable shock? Is there such a thing for bikes?

pyoungbl 08-07-2016 03:56 PM

If the rubber bumper is being compressed isn't it doing its job? Also, if the bumper is being compressed that would indicate a need for more pre-load or a stiffer spring.

Has anyone measured the actual 'throw' of the shock when the rear wheel is moved through the entire range of motion? Most motorcycle shocks do not have a 1:1 ratio of shock movement to rear wheel movement. As already noted, the linkage on the RX3 is very non linear. My concern is that if the rear wheel is allowed to rise too far it will start to eat up the rear fender. The trick will be to remove just enough of that rubber bumper to give maximum suspension travel but not so much as to cause interference problems.

detours 08-09-2016 05:53 PM

2 Attachment(s)
So I installed the new 375/465 spring on my progressive shock.

The install was easy.
  1. Undo the preload (easier to do before removal.
  2. Remove the shock from the bike.
  3. Expose the retention ring by turning the lockrings.
  4. Remove the retention ring.
  5. Remove the cap and spring from the shock body.
  6. Install the new spring and cap.
  7. Re-install the retention ring.
  8. Re-install the shock on the bike.

The 375/465 is longer than the 400/450 progressive spring I was running. This allows more fine tuning of the suspension and allows you to sit more in the travel of the spring. The 375/465 is about as long as the stock spring on the stock shock.

Also, if I understood Ryan correctly, the stock spring is about 400/450. So if you found the stock spring too stiff, this 375/465 is a good choice.

I wonder if the 375/465 would fit on the stock shock? I'll have to check that tonight.

detours 08-09-2016 05:58 PM

The new 375/465 spring was a HUGE improvement over the 400/450!

Not as stiff on road and much better performance offroad. The 400/450 was too strong (given my weight and setup) and overpowered the front, causing it to bottom out offroad. But the new 375/465 allowed the rear wheel to travel instead of pushing that weight forward onto the forks. So the fronts only had to do their own work, instead of the rear's too.

I noticed that the spring felt a lot stiffer at the beginning of the ride but softened up as I worked it on the trail. I expect it to continue breaking in over time and just get better.

BTW, I didn't add any preload to the spring. I just locked it down with a little tension on top of the spring and that was enough for me. With my setup (no bars, no side boxes, 200 lbs riding weight + 30 lbs in top box) I could probably use an even softer spring, but I'm much happier with this one onboard.

Here are my spring recommendations based on total weight (rider/passenger/luggage):
  • light spring - Total weight less than 250 lbs. I don't know what spring rate this would be. I'd have to call Progressive springs and see what's available.
  • 375/465 - Total weight between 250-400 lbs. More travel makes it better off-road. Highly adjustable for varying load.
  • 400/450 - Total weight between 300-400 lbs. More appropriate for on-road riding.
  • 450/500 - Total weight over 400 lbs (I think this is the spring rate CSC offers).

So for most people riding 1-up or light 2-up the 375/465 is the one to get. The spring is longer than the 400/450 so you get more travel overall. And you can set it either lighter or stronger to allow for more variation in rider and cargo weight (just changing the preload as needed).

If your total (rider/passenger/luggage) weight exceeds 300 lbs, the 400/450 spring would be fine but provides little or no advantage over the 375/465.

Around 400 lbs total, I would probably try the 450/500.

detours 08-10-2016 01:48 PM

Quote:

Originally Posted by 3banger (Post 227461)
I have had the Progressive shock for about 4 months now and I per my usual approach; can't leave well enough alone. Here are the modifications I've made. If you notice the bottoming out bumper is almost half of the available stroke and I believe it makes the shock fell unnecessarily harsh. I trimmed mine per the include photos. The linkage rate on the RX3 is very non linear. Zongshen knows that in many markets the bike will get heavily overloaded and built a linkage rate to cope with this. The effect the additional spring rate of the rather stiff foam bottom out bumper is a pretty harsh feeling every time the suspension travel engages it. I feel the suspension has preformed well on some pretty rough trail since I made this mod. Also one of the other off road techniques I've been using is reducing the tire pressure for rides like the Alpine Loop and Imogene Pass. I've installed the guts of a 12 volt air compressor in the right side case.

This is very cool 3banger. I wonder if that's why the progressive shock felt so stiff to me ... maybe I was hitting the bumper.

I'd like to try this too, but do you think the bumper is protecting the shock internals? Or is it really unused stroke?

Also, what did you use to cut the bumper?

2LZ 08-10-2016 02:35 PM

Great write up detours!
So....(drum roll please)....unless I missed it, do you think the new softer spring will fit the stock shock? I could use this, even with my current 220lb arse. How much $$ was the new spring from CSC? I don't mind the dampening of the stock shock but I sure would like to get a little more motion back there.

detours 08-10-2016 02:51 PM

Quote:

Originally Posted by 2LZ (Post 227925)
Great write up detours!
So....(drum roll please)....unless I missed it, do you think the new softer spring will fit the stock shock? I could use this, even with my current 220lb arse. How much $$ was the new spring from CSC? I don't mind the dampening of the stock shock but I sure would like to get a little more motion back there.

I was actually thinking the same thing. The length looks good, but if it's wider than the stock spring, the fixed and preload collars may not fit well.

I did not have time to check it last night, but I will try to fit the short progressive spring tonight. This will tell me if the diameter is a match.


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