Technical > Wheels, Tyres and Brakes
Velocity deep v rims
martinf:
--- Quote from: ourclarioncall on May 21, 2022, 12:36:56 am ---So do all tandem derailleur bikes have undished wheels ?
--- End quote ---
No. It depends on the frame. Either the rear dropout spacing has to be wider than a solo or the dropouts have to be assymetric in order to have an undished rear wheel with derailleur gears. Tandems were often spaced wider than solos at the rear to accommodate an extra drum or disk brake.
--- Quote from: ourclarioncall on May 21, 2022, 12:36:56 am ---Is a tandem wheel simply a rim with more spokes? Or is it wider like an Andra 40? I guess the hub has to match the number of spokes
--- End quote ---
Again not necessarily. There are light tandem wheels and super-heavy duty tandem wheels and various nuances in between. But unless you want to try an esoteric spoking arrangement, the hub has to match the number of spokes.
On my tandem, the front hub was spaced 100 mm and was pretty standard. The rear wheel was spaced about 135 mm (wide for the time, when 5-speed freewheel blocks were the norm). This was because it incorporated a large drum brake in addition to the cantilever brakes front and rear. I upgraded the rims to Mavic 4, which were wide for the 1980's, but much narrower than some current rims, such as the Andra 40.
--- Quote from: ourclarioncall on May 21, 2022, 12:36:56 am ---I know it’s totally overkill but I’ve been looking at getting 48hole CSS rims . Mainly because I’ve always wanted CSS rims and they are the only ones I can find online . Son make a 48hole tandem hub so I think that would be fine with the rim
But the thought of extra strength and bombproofness appeals to me. Saying that , I am almost 17 stone so I like the thought of a super strong rim. I don’t really care about weight . I’m not going to be going very fast especially when loaded up.
--- End quote ---
I do think 48 hole is overkill on a solo bike. Well-built 36 hole front and rear wheels with fairly wide rims and 50 mm or wider tyres should be sufficient even for 17 stone with luggage. 17 stone is about 108 Kg, adding 20 kg of luggage, which is a lot unless you are doing real expedition touring, makes a weight of 128 Kg. With the weight of the bike itself, say about 20 Kg, that makes a total all up weight of 148 Kg, so about the same as the tandem that I used in the 1980's. And unless you are a very powerful rider, you aren't going to be putting in any more power than the combined power of myself and my wife when we were both young and fit.
A non-standard 48 hole wheel will be difficult to replace on tour if it does break, which might be more likely because the holes on the hub flange are closer. I once had a 36 hole hub crack at the flange during a long tour after crashing a loaded touring bike on an icy concrete cycle path about 500 kms from home. I was lucky, the wheel finally collapsed less than a km from home when a section of flange with 3 spokes broke away from the rest of the hub, so I only had to push for a short distance.
And you can always risk having a rim break by hitting a large pothole at speed. 36 hole will be much easier to find if you do break something.
CSS has gone out of fashion. So, although I have them on my Raven Tour, I wouldn't consider getting CSS rims now, as the special brake pads are getting hard to find.
steve216c:
--- Quote from: ourclarioncall on May 21, 2022, 12:36:56 am ---
But the thought of extra strength and bombproofness appeals to me. Saying that , I am almost 17 stone so I like the thought of a super strong rim. I don’t really care about weight . I’m not going to be going very fast especially when loaded up.
--- End quote ---
At my peak around 3 years ago, I was almost 20 stone. At around 19 stone I got myself riding again on a 26“ and a 28“ bike both with Rigida/Ryde Zac 19 rims. Both bikes had been in use regularly at a time I was about your weight.
Most of my rim breakages were worn out rim after 10,000km plus use on flanks rather than other damage, although I did have to repair the occasional snapped spoke which would require re-truing of wheel.
Since buying current bike, combined with healthier eating, I’ve been under 15 stone for about 2 years. I was sceptical about lower spike count and definitely wanted stronger rim, and plumped for Andra 30 rims as the 40 were not right for my frame. The Andra rims (non CSS) are self builds, and so far approx 5-7000km ridden without problems. I’m sure over the same distance on my Zac19 wheels I would have suffered a spoke break or a slight buckle in that distance, but all good on the Andras. I was sceptical that 32 spoke wheels would be up to the job given my weight, but I have been pleasantly surprised.
If you are not riding a Rohloff, I’d suggest sticking with standard 36 hole rims which are cheap and plentiful. There has been enough written on Andra rims suggesting they are truly rugged and reliable. CSS is going to be hard to source unless Ryde decided to do a run of these. But with 10,000km or more on a non CSS rim, unless you are planning a world tour, these should see you good for a long time with replacement rims quite affordable and available as well as a huge range of off the shelf compatible hubs in every bike shop.
From personal experience as a heavier rider, you don’t need to go to extreme non-Standard purchases to find a stable set of wheels. A decent Andra rim on a 32 or 36 hole hub might be enough for you. And if the bike helps you shed a pound or three, that wheel investment will quickly make itself felt.
mickeg:
--- Quote from: ourclarioncall on May 21, 2022, 02:04:46 am ---Okay I see what you mean now in this video
https://youtu.be/2APGsZI4P2k
So have they just widened the chain stays or is the hub ? I searched their website but could see any info . It just tells you the rims and the hub which Im wondering is maybe their own model as couldn’t find it online
Basically I’m wondering if I could recreate this undished setup or is it only available on their bike
--- End quote ---
The Americano is the only solo touring bike I am aware of that uses tandem wheels with 145mm rear dropout spacing. There could be others, but I am not aware of any.
You can buy rims that have the spokes offset to one side to make the wheel undished or reduce the dish. But I do not recall ever seeing one on a 135mm hub, as you typically have a bigger problem with a 130mm rear wheel as that has a bigger difference in spoke tension between drive and non-drive side spokes.
I think you need to go ride your bike. Then decide if your bike is lacking based on how the bike performs. And if it is lacking, then be sufficiently clear on what the problem or failure was.
PH:
I'm around 93kg and I've never broken a well built wheel (Or even those I've build myself ;)) other than occasional crash damage which wouldn't have been avoided by more spokes or less dishing. Even then, it has to be a side impact to cause damage, the front wheel on Mercury I rode into the back of a car and bent the forks on is still round and true, though the hub isn't healthy.
You don't need any other wheels.
ourclarioncall:
Thanks chaps , some good food for thought
I believe the wheels I have now are probably all I need . But a minor and couple of major issues are that I want a dynamo hub and will have to get a new wheel built for that
Also I’ve pondered a long time the type of braking system I want . After considering the pros and cons ,CSS rims are still my preferred option . If they were available at a sensible price in 32h or 36h then I would have been happy with that but I’m too late to the party ! There is one place in Europe that sells them for extortionate prices which I’m not willing to pay. That only leaves one option which is the 48h that sjs have in stock
The minor thing is my current wheels are a little out of true. I had a go truing them last night with a spoke wrench and think I got a little improvement but I guess I would need better tools or take it to my LBS and pay them to do it. How close to true they could get a rim/spokes that may be 20 years old I don’t know . The tool I got from Halfords seemed ok but there were times it was just spinning and not taking a proper hold of the spoke to turn it. Softer metal ? Or the spoke tolerances vary ? Or just a very tight spoke? Do get spoke wrenches made from steel or something harder?
I think if I’m ever going to seriously use this bike then I want the foundation to be right from the start. A Brand new set of wheels and tyres . Then I can monitor from day one how the wheel has responded over time to my loaded and unloaded weight/my riding style /the terrain I’ve ridden over etc.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version