Last August we bought a WOOM 4 to serve as a community bike to be shared by our 3 grandchildren as the grow into it. I did a thread covering the initial assembly and impressions
HERE.
Several weeks back I ordered some upgrades.
The WOOM bikes as sold on Amazon have twist grip shifters by default. The one that came on the bike was stiff and imprecise. I ordered a SRAM X4 thumb shifter. This is what is available as an option if you buy directly from SCAM.
This required a change to 110mm grips.
I ordered a SRAM 4mm cable kit but it wasn't absolutely necessary. Since the ferrules that came with the kit fit the cable adjuster slightly better than the OEM cable housing, I went ahead and changed out the short section of the housing at the handlebars.
Since this would be the first bike with "gears" for the kids, I thought a derailleur protector would be prudent. I ordered a Sunlite derailleur protector.
And last but not least, our granddaughter wanted a mirror just like Poppie's bike, I ordered a Mirrycle MTB mirror.
