waddo

Have just got 6 spokes replaced after maniac vandalism, the bike shop told me that the rims on my bike are ready to be replaced. My wife's bike is only a couple of years newer than mine so maybe we should replace all of them.

Unfortunately I only ride bikes and know nothing about technical things. I have heard several times that 26 inch wheels in Japan are a thing of history. So, would the link wheels be ok?

https://www.sekaimon.com/itemdetail/...ims%20mtb%2026

Scroll down and all the specs are in English.

All advice appreciated.

Doug64

I'm just curious:

• How many miles (km) do you have on your present wheels?
• What type of brakes?
• Why do they require replacement?
• Do you use both front and rear brakes equally (rim brakes), or do you favor one over the other?

My wife's present touring bike 's wheels have 29,000 miles (46,670 km) on them, and still have a lot of miles left in them. However, her older touring bike required a new rear wheel do to rim cracks developing around some spoke holes. She rode into a dangerous storm grate, and it hit hard enough to blow out both tires. This may have caused the damage to a wheel with less than 10,000 miles on it.

waddo

I bought the LHT in around 2015. The bike shop guy who replaced the spokes said the rims are getting old. He didn't say it's urgent but he didn't say plenty of time either. The reasons I am a bit worried: I had a steel frame mountain bike that I used for everything including touring. One evening on a very busy road and only way home, the rim exploded. Luckily I was not hit by a car when I came to a sudden stop. A 25cm strip of the rim where the bakes rub had peeled on and was still attached and the end! Next we are going on our summer tour in northern Japan as usual. This means often cruising down mountains for 30 minutes or longer. We always pump the brakes in such circumstances but the rims are hot at the bottom. I hate to think what would happen if a rim explodes on a long descent.

GamblerGORD53

Grim brakes on tour?? LOL Get serious.
My SA XL-FDD dyno drum brake did 2 tours and 32,000 miles, still works like new. ZERO worries or fuss. Including Vietnam and China, with whole days of slime on the road.
There's ZERO chance it ever gets hot. It has 2.3/ 2.0 spokes with locking nipples, unbreakable. 2 years ago I took it apart to switch from 3x to 2x, cutting the spokes 10 mm shorter. Still didn't break.
I avoid stupid eyelet rims like the plague.

phughes

Duragrouch

Yeah I also want to convert from rim to disc brakes, and my downhills are not that long. Just 80 meters of descent in half km can cause rear drive side spoke break, with all braking on rear (20 inch wheels so smaller heat sink too). Some say I just need better pads, which I'm sure would help, but that energy still must be converted to heat. And after 10 years, rim sidewalls are pretty concave, even with frequent pad cleaning. My recommendations:

Consider cost of rim/wheel replacement, versus selling your bike with just the bad spokes replaced, and buying a Disc Trucker, or other new bike.

I don't think would be economical to upgrade your Trucker to discs, as you would need new wheels, and fork and frame upgrade. I only mention as a local tourer with a Bike Friday, found he needed discs after a few years, and they gave him a good deal on the new fork and rear triangle.

If you replace the rims, get the strongest ones available at the spoke holes, that is the weak point. My road bike I rode light, but 55km a day, would crack rims at spoke holes every 4-5 years but with easy use. Third set of wheels I bought, were double socket/eyelet rims, those distribute the spoke force over both inner and outer rim wall, reducing stress by over half. Every 10% reduction in stress roughly doubles fatigue life. 50% reduction results in 2^5 = 32X fatigue life increase or more. 20+ years later, those rims are still on that bike. Don't know if double socket rims still available, if not, make sure nipple area is extra thick aluminum, look online for reviews for most durable touring rims.

Duragrouch

Link: Permission denied.

26" wheels used to be the most versatile rim size in terms of tire selection, had everything from baldies to knobbies. Now, 700c same (29'ers is just oversize 700c), but many 700c frames lack clearance for larger tires. Many now fit 650B wheels if bike uses discs. But 26" wheels are still very viable, as long as you have good tire selection for them.

djb

hi Mr Great Video Maker but not Technical Waddo--
your mountain bike rim thing happened because the rims were so worn down by years of braking that the side of the rim was very thin and you had not noticed.
You can visually check your present rims by doing the simple "straight edge against your rim to see the wear" test.
This is not my photo, but once in a blue moon I check my rims, but at least it gives you a visual idea of what I am describing.

When I ride in the rain, and especially on dirt roads, I always wipe down my rims with a rag when I get home, and maybe also give the pads a quick wipe too to get stuff off. Doing this keeps the rims clear of abrasivey stuff that does the wearing down quicker and keeps the pads cleaner. I also check my pads sometimes and dig out little bits of rock or even little bits of aluminum from the rim.
This helps a lot to keeping the rim less worn over time, and I also use soft compound brake pads, which are easier on the rim brake surface.

Bonus is stronger braking too generally keeping the rims and pads clean and using softer pads

If the bike store guy was referring to your rim wear, do the braking surface test , take a good photo like this example and show us how much wear is there. That's the only way any of us can give any opinion of how much life is left in the rim.
Also some rims have a wear indicator line in them, when the line (or channel) is no longer visible, the rim material has worn away enough to warrant replacement.

geez, I realize by this time you already maybe have turned off your brain listening to all this blah blah.....

in the past I recall writing to you in a thread about your wheels talking about if your hubs have ever been regreased (the ball bearings inside)
I suspect not, so the hubs could be fine, could do with a regreasing, or could be very worn out inside--who knows, and impossible for any of us interwebs goofs to comment on (although probably will!)--- so thats to say that your hubs could be a factor in the bike mechanics opinion of needing new wheels

busted spokes--rim wear--hub condition---all the factors to take into account and yes, it might be worth getting new wheels, but only a trusted mechanic can help you as you aren't into the technical stuff yourself.

and yes, 26in wheels are still a nice thing, I have 26 bikes still, and like them.
advantages are:
-less or no toe strike to front wheel when turning slowly
-lower gearing overall compared to a taller wheel (better for most of us touring)
-slightly smaller wheel a bit easier packing in a cardboard box for traveling

I still find good tires are available, not the newest tires , but still very good tires
Your frame is made for 26, so you probably cant realistically put 650b wheels on it as the tires will be too close to the frame in places AND it changes the geometry the bike was designed for.

personally, I'd want both your bike and your wifes bike to have to same wheel size, easier for carrying spare tubes etc.

bottom line, you're going to have to trust the opinion of an experienced bike mechanic
good luck getting this sorted

stock photo showing a rim with a fair amount of braking surface rim wear (the concave bit)

djb

if you show a photo of your rim wear, I can take some photos of my most worn rims, so at least you have a comparison
as I said, I can't comment on your hub conditions without actually holding and turning the axle myself, so comes back to trusting an experienced bike mechanic that you know.

waddo

DJB, thanks very much for that thorough and illuminating reply. Actually yesterday night I ordered "dentists calipers" for about 5 dollars. Your simple test in the photo is a great idea but if the calipers work I should get an actual number. I didn't think about hub condition. If the rim's seem still thick enough I will have the bike shop do the hubs. There is a bike shop chain in Japan called Asahi, same as the beer! They are very cheap for labour and the guy who replaced the spokes seemed very competent. Thanks also for the idea about cleaning the rims. Our Tohoku tour this summer is likely to have all kinds of bad weather so from now on we will wipe the rims after riding in rain.

djb

You're welcome, my pleasure.
I need to replace a rim on my disc brake 26in wheeled touring bike because of some splits near the spokes like in doug64 photos. I got some good disc only rims that were a good price, maybe 35 dollars Canadian, dt Swiss rims made for cargo bikes, and need to get someone to build them for me.

If you feel like it, get back here with what you do.
Regreasing the hubs is always a good thing to do.
My favorite softer brake pads are those salmon coloured kool-stop pads. They made a noticeable difference in better braking on my canti brake bike from the stock pads.
All rims will wear out over time, it's inevitable, but wet dirt roads are the worst conditions. I don't ride much in these conditions so I've never actually worn out a rim yet.
My winter bike probably gets the most gritty conditions riding, but I'm in snow and ice and not often on hills, not much hard braking and going slowly anyway.
Cheers

Duragrouch

Yeah, my rims look exactly like that, after 10 years, keeping mostly out of rain, frequent pad cleaning, but the hills here take their toll. At first it was mostly the front rim, which was why I was using only the back brake down a long hill, but that heated up the back rim enough to snap a spoke. My next bike will be discs, for both reasons.

Your points about 26" wheels: Regarding 20" wheels:

- less or no toe strike to front wheel when turning slowly
- lower gearing overall compared to a taller wheel (better for most of us touring)
- slightly much smaller wheel a bit lot easier packing in a cardboard box for traveling (if a small frame like a folder)

ftfy

Doug64

A dentist's crown caliper works great! Look for at least 1 mm of rim wall thickness


Also a micrometer helps measuring the sidewall wear depth. Mine has a gauge that comes out of the "non-business" end and works well.



A section cut out out of a rim I replaced this spring. The spread between beads (outside) on the rim is 28 mm instead of the original 26 mm, which signals a weakness in the rim's sidewall. Also one sidewall is less than 1.00 mm thick which is dangerous, and the sidewall's concave depth at the braking surface is 0.66 mm. Anything over 0.30 mm I take the tire off and check the sidewall thickness with a caliper.



Another thing to measure is your rim width on the bead side. Use an ordinary caliper, micrometer, or a ruler if the tire is off the rim. Compare your rims; they should not be any wider than when they were new. You can also check the manufacturer's specifications.

One of my duties as a volunteer in our school district's Bike Safety Program is maintaining and performing the safety checks on the 37 bikes used in the program. We teach bike safety to 5th graders in the city's five elementary schools. I was concerned after finding an obviously dangerous rim in this spring's inspection. I came up with a method for checking all the bikes' wheels using the tools discussed above without removing the tires from all of the bikes.

djb

Hi Doug, thanks so much for these details and photos. Super useful.
Had no idea about that dentist tool, and I wrongly assumed they would be expensive--they aren't!

Tourist in MSN

Very good discussion of the issue, with great graphics. Thanks for posting. And thanks for volunteering to aid safety.

This reminded me that some people regularly fill their tires with tire pressure that exceed rim ratings. Only rarely do we actually see the max pressure for rims, which varies with tire size. Only rarely is it listed on a rim, but the picture below is from one of my (two decade old) Mavic A719 rims.



Sometimes tire ratings exceed rim ratings for strength. In that case, the rim rating would be the one to follow.

I wish all rims had the rating printed on them, but they don't. And often you can't even find out what a rim is rated for.

But this is the touring board, not racing, I am sure all of us have heavy rims with plenty of metal in the right places on them.

sbrudno

This is a great thread. I have never had a rim issue but I am also not as young as I used to be. I do feel safer on my touring bike with disk brakes, but also like to ride other bikes in my harem. One bike with original rims from the 1970s is one of my favorites so I will think about whether to change riding habits or just be more mindful of where I ride. Will keep this all in mind.