taller, wider, lighter
Here is the new wheel. Speedway Umma built up on a Nimbus (48h) hub.
Compared to my 26" Echo wheel it is 63mm taller, 4mm wider, and 14g lighter!
I think I am going to have fun with this wheel.
I went to put my 150 cranks on my nimbus 29" and the tire was flat which I thought very odd since where I ride there is no thorns, glass etc. So I pulled the tube and submerged it the leak was near the valve stem, not quite on the center line. So I looked in the rim and there are 4 (I assume) drain holes. One of these had worn a hole in tube. They matched up exactly with the hole in the tube. So I filed/sandpapered them smooth and reinstalled a 29" tube (had been 26 which might have contributed to the hole.)
So just a heads up, you might want to check how sharp those holes are on your rim and smooth them out a bit. This was on the stock Nimbus 29" touring rim. I was going to line them with some tape but decided against it, but that is part of the reason I went with the thicker 29" tube.
I didn’t take any pictures.
Also one of my bearings is rough and is getting a click. The uni is only about a month old, and I would say has less than 100 miles. I’ll get in touch with UDC on Monday and see what they have to say.
I just noticed that I said 14g lighter, I meant 140g I am curious to see whether I will prefer longer cranks with it because of the larger diameter or shorter cranks due to the decreased weight. I will report back once I get some miles on the trail.
ezas: are you saying that you are not using any kind of rim strip at all? It is pretty important to prevent wear on your tube from the spoke holes etc. they also help prevent the tube from herniating through those holes.
Sure my rim has a rim strip. Not at your level but I have seen inside a rim or two.
There are four of these holes and they are outboard of the rim strip.
These holes are above the rim strip as you move up towards the edge of the rim. There is a shoulder in the rim and the holes are right on the apex of the shoulder. The holes are maybe 3mm.
If you have no idea what I’m talking about I’ll peel the tire tomorrow and take a picture cause I know you have had your peepers in a rim or two so im surprised you don’t know what I’m talking about, though I have to say I can’t recall seeing these holes in any other rim. Something unique to the nimbus 29" road rim maybe.
I had the same problem when I got my Nimbus. I also couldn’t think of any real function for those little holes, they might just be used in the manufacturing process. I never managed to make their edges smooth enough to avoid getting flats and I ended up putting small piece of fairly heavy tape over them.
Looks like the weight savings is from being single wall on the larger rim? I’m curious about intended use – wider implies muni, but I thought conventional wisdom was to use double wall for anything beyond basic riding? Anyhow, looks great, and looking forward to the ride report!
In my experience with those two-wheeled things, anything that’s not smooth inside the rim absolutely needs tape, or you will get flats from it. Not sure what the deal is with the Nimbus rim, but I think Canuck’s right on with using tape over the little holes.
I actually started to put tape over them and then decided against it in case they were for drainage. Im now running a normal, feels pretty thick 29" tube (I was using a stretched out 26"). That and the smoothing I think are going to make it a alright. I might deflate my 24" and see if it has similar holes.
i just noticed that both my Echo and Speedway rims have the holes. They are covered by tape though.
My light and wide 29" setup is going to be for XC type rides. I am going to build up a 3" or so wide tire for it and it should be great in iffy snow conditions and loose/semi-loose terrain. I will keep the 26 for trying the stupider stuff.
Depending on riding style I think that single wall rims would most likely be an acceptable choice for many riders off road. As long as the wheel is well maintained it should be strong enough for what I am going to throw at it and a wide tire helps absorb shock and protect the rim.
We will find out when I ride it in the Flin Flon rocks this summer.
Early on I was thinking just like you (and using a 29" tube) but after my third or fourth flats in a couple of days I gave up and covered those holes with tape. By the way, my last flat was not close to the valve but on the opposite side; my rim has identical holes on the opposite side too, which of course I only noticed after getting the flat! The fact that the holes are on each side of the junction makes me think they are only really useful during the manufacturing process (to be able to grab and bend that strip of metal). If they were for drainage they should be more uniformly distributed and not all beside each other.
Thanks for the heads up. Ill plan on hole taping for later today and will check for holes on other side of rim.
First Aid Tape works as Rim Tape
I have the exact same situation with my Nimbus 29er and stock wheel. Corresponding to one of these holes, I have a spot worn through in the tube. I’ve covered the holes up with cloth first-aid tape - it works perfectly as a rim tape, too.
I don’t think the holes are for drainage. Once the tire is inflated, the tube would seal up these holes and they would not be effective for anything except for creating the need for tire patches in the future.
-David
I’ve been on the fence about buying a dedicated muni. Was thinking of just sticking a Kenda Small Block 8 tire on my touring Nimbus. Anyone see a problem with this? It is 29 X 2.1 and the tire it came with was 29 X 2.3 so clearance shouldn’t be an issue.
I was thinking of getting a 26" but in reality I can climb as well on my 29" as I can on my 24" and I enjoy the speed and momentum of the 29". Seems wasteful to run out and buy another 29er for just for off road when I’m already doing pretty well on trails even with a road tire.
Next time I have the tire off I will look for those little rim holes that you guys are talking about and tape them accordingly.
deadbeatpope,
A few weeks ago I put a Kenda Nevegal on my 29" and have been very pleased with it. It is a light mountain bike tire with good performance on dirt trails, OK on rock and OK on street. It is a lot lighter than the Stout tire that was originally on my 29". It should work well on your Nimbus.
Scott
We seem to be in a similar situation, and with the same 29" uni. You might have seen the thread by Munimutant recommending the Small Block 8 for cross country riding
http://www.unicyclist.com/forums/showthread.php?p=1292970
People seem to be recommending tires with round profile, there are quite a few possibilities for light weight tires at or below 2.3" that would fit in the Nimbus cruiser.
I’m having good luck with the WTB Wolverine 2.2 on the nimbus cruiser.
Thank you both!
I hadn’t seen that until now. Thanks for digging that out of the files for me.
Recently I came across a pair of SB8s on craigslist barely used for $25 but was busy with work and couldn’t get them. The other night I saw a MTB with them and thought they looked like a good choice for the uni.
It appears that these 3 tires are within about 5 bucks in price so that isn’t a motivator. The SB8 is the lightest, goes up to 80psi and seems like it would have the least rolling resistance by tread pattern. I think I’ve made my choice but I like to chew on an idea before I lay down the plastic. I like to hear what my fellow uni-tics have to share too.
Before I decided to go with a ridiculously heavy Kodiak for my 29" I was seriously considering the Geax Saguaro 2.2" for mixed road and trail use. According to the [url=http://mtbtires.com/site2/tire-specs/65-700c–29q/62-29q-700c-tire-specs]29er spec comparisons it has a good combination of weight, width, and volume. Several reviews I read mentioned how well it worked at low pressures which is a good indication of decent sidewalls (relatively speaking, like most 29er tires it is a single ply tire after all).
Before I decided to go with a ridiculously heavy Kodiak for my 29" I was seriously considering the Geax Saguaro 2.2" for mixed road and trail use. According to the 29er spec comparisons it has a good combination of weight, width, and volume. Several reviews I read mentioned how well it worked at low pressures which is a good indication of decent sidewalls (relatively speaking, like most 29er tires it is a single ply tire after all).
That is a handy little chart. What convinced you to go with the “ridiculously heavy” Kodiak?