I searched for a while to find a shock that had some adjust-ability besides preload. When I found the shocks on eBay, I didn't pay attention to spring rates because I was not aware it might be something I needed to worry about.
After not being super happy with the $115 eBay shocks on full preload due to the rear tire scraping something, I figured out how to calculate the spring rate using the basic calculator at this site:
Although not every seller will list the specifications for the cheap shocks they sell, I did find a set of 340mm GZYF shocks on sale at Walmart after wading through a few pages of similar looking shocks at various price points and found a set on sale for less than $60 with free shipping. Most of the shocks had 7mm diameter springs which would have been the same spring rate as what I already had.
10 years ago I spent roughly $60 on a set of generic Emgo shocks that now sell for roughly $90 but I found the pre-load settings could not be set to my liking with just 4 or 5 positions that either made them too soft or too hard. Luckily, the swingarm swap forced the issue since the mount changes (eye to clevis -> eye to eye)
My hope for this go-round is to get a set of shocks with 8mm springs that I can swap onto the shocks I have, effectively upgrading my spring rate from 59 to 92 lbs/in which is more than the 78lbs/in that is recommended on another calculator that I found on the web here
 |
| shock specifications from Walmart listing for GZYF shocks |
When I received the shocks, I found them well packed in a fancy package and I was immediately impressed by the presentation for $60. I was initially planning on trying the new shocks to see how they were before swapping the springs over, but once I had them swapped with the longer eye adapter and slapped them on the bike, I really liked the way they looked.
I shouldn't have been surprised how much heavier they were compared to the other shocks due to the additional complexity with the piggy back design (and larger springs), but I was.
Although these shocks still needed some pre-load, it didn't need to be cranked all the way to the stops like the original shocks which just seemed better suited to a smaller bike. So I think I'll just leave this piggy back set on and worry about swapping springs if these shocks fail prematurely.
I think 2 turns on the pre-load may be a little too firm so I backed it off a half turn. This reduced the stiff jittery ride and still had good control on a big dip in the road at speed. They do feel better than the emgo shocks from the old setup but I'm not sure if the lighter swing-arm and rear wheel are part of the improved feel (most likely!)
Follow up thoughts: I've seen some people mount piggy back shocks upside down with the reservoir on the bottom due to mounting issues where the clearance doesn't allow space for the extra shock body parts, but putting the heavier stuff on the bottom adds unsprung weight where mounting it with the piggyback on top, does not change unsprung weight. Given the weight of these shocks, you could potentially add an extra pound or 2 to your unsprung weight. Avoid mounting these upside down if at all possible.
Comments
Post a Comment