Quote from: Naranja_CT5+ on October 10, 2023, 04:43:45 AM
Even if you are using the proper diameter tire how would you even know you are getting the correct distance?

I used Apple's Map app to measure a local circuit of streets. It's 2.0 miles, but i found that a I might have to roll blocks further for the odometer to accumulate 2 miles. What's more, some days it was more accurate than others.

Decades ago, I measured the local walking track with a tape. It's exactly 3/10 of a mile. A sign prohibits bicycles, but the track is pretty much abandoned and I'm a scofflaw. On my Radrunner, If I dropped a marker when the trip meter turned up a tenth of a mile, it would turn up 3/10s higher when I reached that marker again. My Radmission was just as accurate.

That was only true if I kept my speed down to about 6 mph, which was hard to do.  If I sped up a little, maybe 9 mph, I might have to go 30% more than a lap before the odometer added 3/10. If I want faster, say 12 mph, the odometer might register 3/10 when I'd been only 60% of a lap.

The neglected track is rough. On both bikes, I guess the magnetic wheel sensor in the motor gets erratic on bumps.

Quote from: Radio Runner on October 09, 2023, 07:34:17 AM
Most every replacement chain now days comes with a master link.

Prebuilt bikes often do not.

SRAM, KMC, Whipperman-Connix make good chains.

Thanks. In my size, I see that KMC offers a 1-pack and a 2-pack, each about $4. They look alike, but the single one is not supposed to require a tool.

I have a chain breaker. (Actually, I have two, but I've misplaced one.) It looks as if I'd need special pliers to snap and unsnap a Missing Link. Some turn out to be of useless quality, and if I got a good pair, it would be one more tool to misplace. I think a pair of circlip pliers would do the trick, or a pair of #6 finishing nails.

I was going to buy a stretch gauge: one more thing to lose. Now I see I don't need one. In 20 links (254mm) a 0.75% stretch would be about 2mm. Who needs a gauge?

Quote from: Naranja_CT5+ on October 09, 2023, 05:02:44 PM
I'm not ready to give up yet. Just getting a bit impatient that I can enjoy riding it (before it gets too cold.) Gotta order winter gloves now :-)
Lastly, I don't trust EBR, I think he's just a sales arm of RAD power bikes.

When it's below freezing, a scarf makes a big difference. The brim of a cowboy-style hard hat keeps the wind off my face, and the weight of the hat keeps it from blowing off. I bought some nice ski gloves last winter, but I had so much trouble pushing the buttons of the OEM Radmission display that I cut off the end of the thumb of the left glove.  The cause of the problem turned out to be the defective design of the controller, dadburnit! Now that I have an aftermarket controller, I wish I'd saved the end of the thumb so I could sew it back on the glove.

In 2022, I had two Radrunner spokes broken. The Radpower site didn't list those parts, and Support didn't answer. For $25, I ordered a set of 130mm WLKY spokes from China.

I hadn't read enough detail about spoke length to measure correctly. I had to bend the new spokes to get them in place, and if I had to tighten a nipple another turn, I might run out of thread. I should have ordered 125mm.

Some of the OEM spokes had heads that were slightly small. That had led to stretching and breaking. I prefer the WLKY spokes.

Weeks after my inquiry, Radpower Support told me they now carried spokes. I don't think the description said how long they were.

Quote from: John Rose on October 09, 2023, 04:23:58 PM
What if you just shift it up to the highest gear to get a bit more slack? Can't you then get the bottom of the derailleur submerged in a container of solvent?
Or use a narrow rectangular pan to get a longer section of the chain submerged, slowly turn the pedal by hand, and work it with a brush.

Both my bikes are 1-speed. I bought the Radrunner first and had misgivings about no gearshift. I found that it's not necessary with an ebike. Instead of shifting down on a hill, you add motor power.

I took the back wheel off to change inner tubes. That gave me a chance to clean the black waxy buildup from the rear sprocket and the tensioner (a one-speed derailleur ). Strangely, the buildup wasn't gritty, and the front sprocket was clean.

I wiped several times after dipping, and the chain was clean to touch. Then I put a drop of Finish Line on each side of each pin, a total of 3ml. When I touched the chain the next day, it left a sort of sticky soot on my hands that, as usual, was hard to scrub off. I had thought that stuff came from the factory oil that I hadn't completely removed. Instead, it seems to come from the Finish Line. I don't know why it turns black after application or why grit doesn't stick to it.

Quote from: Radio Runner on October 09, 2023, 07:34:17 AM
Most every replacement chain now days comes with a master link.

Prebuilt bikes often do not.

SRAM, KMC, Whipperman-Connix make good chains.

Back in the day, it seemed like all bikes big enough to have pneumatic tires also came with master links. I wonder what changed.

Quote from: v4ssily on October 09, 2023, 04:41:19 AM
This is an interesting discution.

Does anyone have tried this 20" convertion or the 24" ?

I've a motor failure with my radwagon and this could be an option don't you think ?

Bafang anticipated your problem, where the motor turns but not the wheel. A new motor clutch costs about $25. That's bound to be cheaper and easier than replacing the motor.

The ISO number, usually on the sidewall, provides a fit by showing the bead diameter and the width. I believe the RW4 uses 62-559mm. I believe it has 45mm rims, which, according to a chart I have, will work with tires 2.35 to 4.20 inches ( 60  - 107mm ).

Modernbike.com lists 698 tires with the 559 mm bead, and too many to count are between 60 and 107 mm wide.

I started using dry chain lube 19 months ago because the grime resulting from oily lube wasn't good for my pants or the chain. I've cleaned the chain repeatedly, but cleaning it on the bike is not thorough. Yesterday I went so far as to remove the back wheel so I could dip sections of the chain in mineral spirits, then do a lot of wiping. It wasn't thorough.

I want to take it off, roll it up, find a can just wide enough, and soak it in solvent. That was easy when chains came with master links. I guess I'll have to break the chain and add a master link.

Why don't chains come with master links these days? Is one type or brand better?

If I were in your shoes, I think I'd cancel.

Ryan who runs this forum, posted a youtube video comparing the RR6+, as I recall, to Aventon's equivalent. Based on that review, I'd prefer the Aventon.

I trust him better than I now trust Electric Bike Reviews, who in 2020 persuaded me to buy a Radrunner.

Quote from: v4ssily on October 07, 2023, 07:44:02 AM

When I pay attention, I can here some noise coming from the motor when turning the throttle, but the wheel wont turn or at best just moves a little.
So my guess is that I need to replace the motor.

If the motor turns and the wheel doesn't, that sounds like the clutch, a freewheel assembly in the motor that lets you pedal or coast without turning the motor. The assembly includes the gears and costs about $25 at Amazon. There's probably a youtube video for your particular motor.

Adjustment would depend on what display you have.

I found the diameter of my "20 inch" tire by measuring from the center of the axle to the floor, with the tire touching the ground. Doubling it showed a diameter of 23 inches.

Quote from: John Rose on October 06, 2023, 03:47:07 PM
Well, thanks for all that.
I wonder if latex tubes influenced the adoption of nitrogen for filling tires. Larger molecules being slower to leak through, and non-oxidizing.

QuoteFor my Radmission, I've ordered tubes that just say "butyl."

What about "May or may not contain nuts"? 

The NHTSA tested and found the loss difference to be insignificant. So did Consumer Reports. They pumped up 31 pairs of tires, 1 with nitrogen and 1 with air. After a year, the nitrogen tires had lost 2.2 psi on average and the air tires 3.5. (Tubeless tires have a butyl coating.)

Recent research suggests that the difference may be due not to permeation through the rubber but to oxidation with the rubber. With 18-wheeler truck tires, the pressure loss with air is fastest when the tire is new, and so is the deterioration of the strength of the casing; if you buy a tire that was recapped after a year, it won't lose as much pressure and it will hold it's remaining strength better. They conclude that the oxygen is not passing through the rubber but "rotting" the inside surface. Nitrogen could pay off by preserving the casing for more recaps.

Airplanes started using nitrogen because it wouldn't support combustion; when you retract your landing gear to head across the ocean with 400 passengers, you want to be sure a tire isn't smoldering from overheated brakes. Airlines noticed that with nitrogen, the pressure difference would be smaller when you took off from a place with one temperature and landed in another temperature.

That's why race cars started using nitrogen, to reduce the pressure change between cold and hot tires. They said it was because nitrogen is dry. I doubt it. To cause a disproportionate pressure increase as a tire warms, there must be liquid water when the tire is cold. My compressor tank sits between 125 and 150 psi at 100% relative humidity; excess water condenses and goes to the bottom of the tank. If a racing tire is inflated to 10 psi, air from the compressor would be around 8% relative humidity. The moisture won't condense in the tire.

I think it comes from off-gassing. It will cause a strong odor if you deflate a new tire in the garage, and race cars use new tires.  As the tire heats, more of those gasses will come out of the rubber, and they'll be reabsorbed as the rubber cools. When you fill a tire with nitrogen, you do it several times in order to purge the gases in the tire. That could reduce subsequent off-gassing. You could purge just as well with compressor air.

Have you seen what dealers charge for putting nitrogen in tires? It causes inflationary pressure!

Oh yeah, the tubes I bought seem to be identical to the unsatisfactory ones I replaced. I guess "butyl" doesn't always mean "butyl." Latex forms tiny bubbles as inner tubes bake in a mold. That makes the tubes spongy. Some companies control the bubbling better than others, but the best way is to start with 100% butyl.

Foreseeing war shortages, German companies discovered nitrile rubber in 1934, and American companies discovered butyl. Shortly after Pearl Harbor, the Japanese seized the East Indies, source of 90% of America's rubber.

Butyl was so much better for inner tubes that America didn't go back to latex after the war. It's impermeable to air and doesn't age from exposure to oxygen. (Dunlop recommends replacing latex inner tubes every 6 months.)

BMW Motorcycles went back to latex when the R75/5 came out in 1969. Consumers often failed to check tire pressure and often rode over 100 mph. With an underinflated tire, friction could heat a butyl tube at that speed until it gave way in a blowout. Latex flexed with less friction. It wouldn't heat up as much, and if it did let go, it would release air more slowly.

These latex inner tubes were porous. I didn't have to check with a gauge because I'd know in 50 feet if either tire was 3 psi low. American bicycle tubes were going back to latex about the same time. More and more, bicyclists were buying helmets and bending way over to try to keep up with cars on bikes with narrow tires. Even with higher pressure, a smaller footprint could mean more flexing, producing heat for a smaller tube to absorb, and higher speeds would generate the heat faster. For a rider with his head down and forward, a blowout could be dangerous, so latex was preferred.

After a year of adding air to my Radrunner tires, I decided that the tubes were porous. It didn't occur to me that a 20-mph utility bike with tires as big as motorcycle tires would have latex tubes; I just thought they must be cheap. I installed butyl tubes. That reduced losses by 90%, but they still leaked and I didn't know why.

My Radmission tubes also lost air. I'd have to get out the pump every couple of days or settle for tires that were increasingly low. I hoped to seal them by adding a lot of Slime. It didn't work.

I find the chain stays on my Radmission too short. It means the back tire carries 40% more weight than the front. Today I tried 50 psi rear and 40 front. It's great. Now that I've found a good combination, I want to keep it that way. When I checked Amazon for butyl tubes, I found out why the butyl tubes I bought last time are a little porous. The description says they're made from "a butyl compound." I learned that most bicycle inner tubes these days are made from a mix of latex and butyl. "A butyl compound" must be a salesman's description of a mix.

For my Radmission, I've ordered tubes that just say "butyl." Maybe I'll finally have tires that hold air, like the old days.

Quote from: John Rose on October 05, 2023, 03:08:14 PM

I have a RadMini ST2 (2020) and I was able get to the menu and change the setting from 32 to 40 km/h. However, on my test drive the next day (level paved road, teeny bit of tailwind, full twist throttle), the top speed I could get was about 34 km/h.
Whee!

I double-checked the setting afterwards just to confirm that it did not somehow reset to 32 after powering it down.

My 750 watt Radmini produced 500 watts of mechanical power. My 500 watt Radmission produced 350 watts. With aftermarket controllers, they produce 1000 and 700 watts, but both top out around 38 km/h. Back EMF seems to top out these motors at that speed, and going to a 52-volt battery would mean only a slight increase in speed.