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I need a whole new front wheel.

I have been around some of the bike shops in my city and found that the cheapest whole new wheel (wheel, tire, tube, tape) is about £55.

I also asked at the shop I bought my bike about getting a like for like replacement (i.e. the same make of wheel that I am replacing) and the guy helping me said that would cost about £100, probably a bit more.

The increase in cost is because the hub (sorry for my lack of expertise) is aluminium and the rims are double walled rims (which I think are sprint rims judging from the picture in the wikipedia article). He explained that double walled rims significantly increase the strength of the wheel, which is important when hitting potholes.

I have a hybrid bike, and ride almost entirely on road. I currently ride about 54 miles a week, and I'm hoping to increase that to nearly 90 once I'm fit enough, so I guess that's low to medium usage. The roads around here are fairly potholey, but I manage to avoid the holes most of the time.

This is the bike I currently have: http://www.giant-bicycles.com/en-gb/bikes/model/escape.2/7090/43391/ (without the front wheel!)

Given the above, is the more expensive wheel worth the extra money?

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  • Likely the "CR18 DW" rim in the specs means 18mm double-walled. The Giant Escape 2 retails for around 400USD, so it's not a particularly fancy, high-priced bike, but is a step or two above the department store "BSO". Certainly serviceable. It's really up to you whether to spend the additional money for a more durable wheel -- I'd spend it, but then (even though I'm a bit of a skinflint) money isn't that tight for me and I'll generally pay more for value and durability. The cheaper wheel will probably hold up fine for 5000 miles, by which time you may be ready for a new bike. Jul 17, 2011 at 18:42

4 Answers 4

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The "sprint rim", as described in that article, is a "tubular" rim -- intended for a glue-on tire (which maybe your grandfather saw once). You'd know if you used glue-on tires (and you wouldn't be complaining about spending only 100 pounds for a new wheel).

Other than my old Schwinn (Schwinn had double-walled steel "tubular" [in a different sense] rims on most bikes until maybe 1975) I don't think I've ever had a double-walled rim. My rims have always been extruded aluminum ones more or less along the lines of the "Rim" picture near the top of that article. Such a rim usually has the hollow area similar to what's shown (which makes it "double" in one sense, I suppose), though the height of the hollow area may vary from maybe 3mm to 20-30. These rims don't (as a rule) have double sidewalls, though.

Since the "sprint rim" apparently sort of looked like what you have now, I suspect you have an extruded rim where the hollow area is fairly tall and with a triangular cross-section. Such rims are fairly popular in medium-level road bikes, I gather, partly because they "look sexy", but in addition they probably have a slight advantage in terms of dent resistance, though mostly in wheels with low spoke counts where the spokes aren't able to do the job as well.

You don't say what width tire you run. I've never seen rim sidewalls wear enough that their structural integrity was threatened, but I've always run tires wider than 30mm. I suppose some of the narrower, more lightly built rims may be in danger of wearing through (though it seems to me that a thicker sidewall would be of more advantage for the weight than a double wall).

Why do you need a whole new front rim? Did both rim and hub get damaged somehow?

Added

A little Googling shows that many refer to the box cross-section extruded rim (which I believe is normal on any medium-priced standard rim) as "double walled". This has nothing to do with the sidewall being doubled.

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  • The wheel was stolen. The rest of the bike was secured and remains. I have learned my lesson.
    – Matt Ellen
    Jul 16, 2011 at 22:28
  • Thanks for the explanation of the sprint rim. I really don't know much about bikes. You are right, I think it is an extruded rim, as you description fits what I was shown today. I'll find out the tire width and add it to the question.
    – Matt Ellen
    Jul 16, 2011 at 22:36
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    If it's a hybrid bike, as you say, the tire width is probably 28-40mm, and would not be any sort of fancy "racing" rim. You do want the extruded rim with the hollow "box", though, as those are significantly stronger than a simple U shape. In the US you can get a decent quality front wheel (eg, rei.com/product/770552/deoresun-cr18-front-wheel ) for well under 100 dollars, but of course we don't have a VAT (or any cash in the treasury, for that matter). Jul 16, 2011 at 22:50
  • Thanks @Daniel. I'm not 100% sure but I think it's 37mm, which sounds about right.
    – Matt Ellen
    Jul 17, 2011 at 13:14
  • When looking at rims, note that the quoted rim width (which may be quoted as either inside width or outside width) is generally much narrower than the tire width. Here's a chart that relates tire width to inside rim width: bicycletires.com/a_49/tire_width/article.htm . For your 37mm tires an inside rim width of roughly 16-24 would be OK, per that chart. (I'm sure other charts vary by a couple of mm one way or the other.) Outside rim width will be roughly 4mm wider. Jul 17, 2011 at 13:30
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Extruded aluminum double wall rims are pretty much standard now (they are very much stronger than the cheap single wall rims).

Can you post a link on the bike you currently have ?

Cheap yet good quality wheel :

http://www.bike24.com/1.php?content=8;navigation=1;product=900;page=1;menu=1000,2,140,17;mid=0;pgc=0;orderby=2

Update :

OK - it is not a top quality bike, but still a good one that should last quite a bit with proper care (cleaning, lubing, changing chain when it's time, etc). Probably more than 10.000 km. Much much better than budget bikes that are totally destroyed after 1000-2000 km.

So it makes sense to put a good quality 50€ wheel on it.

FYI, I just bought a wheel for 100€, it has a Shimano 3N80 dynamo (which is expensive), excellent quality spokes, and an very tough rim designed for loaded touring (forgot the name).

Basically in bike gear there are three broad "zones" : - cheap crap - reasonable price, reasonable quality - expensive stuff whose purpose is mainly to shave off some weight or survive extreme conditions

Without dynamo, you can get a good quality wheel for 50€ if you shop around. Don't spend 100 quid, it's not necessary. But don't spend 20 quid, you'll get crap.

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  • I have added a link to the bike in my question. Should have done that in the first place!
    – Matt Ellen
    Jul 17, 2011 at 17:43
  • Your current wheel is double walled, if the link to your bike is accurate. I definitely wouldn't recommend getting a downgrade...
    – zenbike
    Jul 20, 2011 at 18:05
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A double walled rim is significantly stronger, assuming all else is equal. Only you can decide if your budget allows for it, or it's worth it to you, but it's not hype. They are better wheels.

That said, a bad pothole, hit at any speed, will destroy the strongest wheel available. You need to learn to avoid obstacles like that, or ride them smoothly when avoidance isn't possible. Or you'll buy a lot of wheels.

If you know you will hit unavoidable obstacles, the stronger wheel will last longer, but will fail at some point also.

Edit:

Double walls are mechanically stronger due to additional bracing between the sidewalls. Not a thicker sidewall... See photos.

Double walled rim: Double wall rim

Single walled rim: enter image description here

Edit 2: Your current wheel is double walled, if the link to your bike is accurate. I definitely wouldn't recommend getting a downgrade...

Hope that helps.

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For you, on your mileage, are definitely a worthy investment. Before explaining why I must correct you on your low to medium usage comment - in the UK the average cyclist manages to average all of 17 miles per week. Maybe you are not part of the high-miler club but you can fairly claim better than average usage when amongst lycra-clad folk and high usage when with civilians.

As for your question, the problem with single-walled rims is what happens to them when they wear out. Rims only wear out on bikes with brakes that work on the rim, so maybe this point might not apply. However, with single-walled rims, when the brakes wear through the rim, the problem is that the rim deforms, to bulge out (due to the pressure of the tyre). This can result in a blowout, although in practice this is a rare occurrence.

Meanwhile, with the double-walled rim, if it wears completely through, the inner wall is still strong enough to hold it together.

There are some single-walled rims with a wear indicator on them. This is a groove that should be visible in the side wall. When this is worn off and no longer visible it is new wheel time.

As for pot-holes, really any rim should be up to the job as it is the tyre and not the rim that takes the impact. If you damage the rims by hitting anything (even a kerb) then that is due to not enough air in the tyres.

Keeping the tyres at the right pressure is also important for puncture resistance and tyre longevity. The best plan is to invest in a track-pump with gauge and to check the tyres fortnightly. You can stretch this out to monthly, however, having tyres inflated at less than the side wall stated value also means you are going slower, not really with a more comfy ride, just slower. Stretch your budget to get a decent track-pump if you have not got one already.

The other top tip for looking after your wheels is to clean the rims. It doesn't matter if you clean nothing else on the bike, but do clean the rims. The build up of dirt and grime works as an abrasive paste that also makes your brake pads wear away quickly. To clean them is only a five-minute job, any damp cloth will do - hold the cloth against the braking surfaces and spin the wheels around. Maybe build this into your fortnightly pressure-check routine.

There are untold treatments for rims (e.g. anodizing), different sections (e.g. aero and box), different ways of holding the spokes (e.g. eyelets), different ways to do the join (e.g. welded or with an extra bit riveted in), sidewall finishings (including the wear indicator) and materials (variants of aluminium or ultra-lame steel). The options are far too many to make a sensible choice, however, if there is one thing you should fork out for, then that is the double-wall for the safety reasons that will only come into play a long way down the line when wear takes it's toll. That is what you are investing in.

Fundamentally the double-walled rim is a different product than the single-wall version, with heat-treatment and other process that make the extra money worth the while. You also can get decent eyelets on them and better joins, i.e. without a rough seam. The extra lightening of the wallet for them may be painful at the time but this will soon pass.

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