I enjoy mountain biking, especially off-road mountain biking. Over the years I have found some handy websites for mountain biking.
First of all I use a Garmin smartwatch to track my rides. I had a Vivoactive 3 first, then upgraded to a fenix 6X Pro Solar. I use Garmin Connect and Garmin Explore website the most since they have the most detail for a Garmin user. Since my rides take me outside of cellular coverage, I also have a Garmin InReach Messenger to track and stay connected. Garmin has done a fantastic job with these devices.
Here are some other website I discovered and use:
Strava. This is a social biking website. It sync's with Garmin well so my rides tracked with Garmin Connect also post to Strava.
Trailforks. This site is a place to find and share routes.
PinBike. This includes classified ads for bike stuff.
I ride mostly off road which includes steep hills, loamy sand and gravel, and technical trails. The original gearing on this bike seemed more pavement focused and the gear ratios were too tight, and too geared for high speeds for me. The original gearing had a 52 tooth chainring up front and a 28-24-22-20-18-16-14 freewheel. First gear was far too high for steep hills and technical stuff.
Changing the chainring was simple. I bought a 44 tooth chainring. I swapped that out and it immediately helped but I did of course loose top speed.
The connector is too big for the nut to go over and the nut is too big for the tool to go over. I had the motor apart to see of there was an easy way to remove the wiring but no, it is all soldered in. I did not want to hack the wiring up so I needed a better way. I finally decided to get a larger fitting to replace the nut and slot it so the nut can be installed without having to go over the electrical connector. Having a slotted nut is not great as it is much weaker this way so I found an item made for something different and modified it for my needs. Here is what I used: https://www.amazon.com/dp/B07T18ZKH1?psc=1&ref=ppx_yo2ov_dt_b_product_details.
Not ideal as stainless is softer than I wanted, and it needed significant modification to work for what I needed here. I had to drill out the unthreaded end, reduce its diameter a bit (grinding), and slot it to fit over the wire. Having a slot in a nut like this weakens it substantially but this is far thicker and longer than the nut it had. Just to make it stronger, I bought a 7/8" shaft collar from Tractor Supply that goes over the special slotted nut to clamp it down which both locks it to the axle and eliminates the weakness caused by the slot. I also had to grind flats on the new nut so I could tighten it on the axle. The result, crude as it is, looks like this.
I was able to get plenty of torque on it, similar to the original nut. The collar then locks it in place and strengthens the nut. Now I can easily remove these to swap out freewheels. Here is what the gear ratio comparison looks like, Opt1 being the new gearing.
Torque in this chart is just the ratio from original, 1st gear having 144% of original 1st gear torque for instance. The speeds are derived from my "typical" pedaling cadence (estimated). The lower 3 gears give more torque and less speed than original. The upper 3 gears give higher speeds than the original. This give a much wider ratio between the low and high gears.
My first ride with this new setup was much better at climbing hills. In the more difficult stuff, I could power through in first gear now where I could not before. At times I started having traction problems now where I would spin the real wheel. I ordered a more aggressive rear tire as mine was worn and had a damaged sidewall as well. After searching through all the options, I ended up with a Zol Montagna (available on Amazon: https://www.amazon.com/dp/B08KFMHLHJ).
I have been on many rides since these modifications and the bike is much better suited to my off-road focused riding now. Since this freewheel has wider ratios, it still works great for higher speeds on pavement too (actually can go a bit faster than before). I have considered other mods like switching to a cassette style rear gear, going to a 9-speed, etc., but for now I am pretty happy with it. I use that low first gear quite often off-road when climbing hills or in real loamy conditions and it makes a world of difference. In super tight situations I can ride it in 1st without motor power and it is so much more useful than before.
A few things have changed since my last update. The issue where the motor would cut out intermittently got worse. I contacted Rurui support and after many emails, photos, and videos, and tests, they sent me a new display and controller.
After I replaced these 2 items, and fixed some damaged motor wires, the bike performs far better. The controller appears to be a later version. I immediately noticed a big power gain especially in PAS 1. It used to top out at about 11mph in PAS 1 and not it is more like 13.5mph. The biggest difference is the power everywhere, and that it sustains that power even on long hills. I have now taken it on about 5 rides, including long hills in loamy terrain, steep hills, and some paved trails with long climbs. It performs so much better now. It no longer surges or cuts out like it had done since I bought it.
Upgrades since my last post
I replaced the 52 tooth chainring with a 44 tooth. This give me better low speed performance for off-road. It translates to about 18% more torque (and lower speed) from my pedaling. Of course this is a trade-off with top speed which is also reduced 18% but I ride mostly off-road and don't need the higher speeds. Now with the improved motor performance, and this addition climbing torque, I can climb hills I never could before.
I also bought a wider range freewheel but you can't replace it without removing the motor wiring. The axle nut is too large for the freewheel or freewheel tool to go over and the nut threads are too small for the motor connector to go through. It appears I will need to unsolder the wires from the motor, or cut and modify the wiring so I can take this apart.
I heave searched the net for a solution but what I found so far have been mostly people hacking the harness apart and band-aiding it back. Yuk.
I had to replace the rear brake pads from all the long hill descents I make on a regular basis. Here is where regenerative braking would really help. Just riding the brakes down long hills is hard on them.
