Condensed answer:
All rim tape can indirectly trigger a flat when it’s not covering the spoke’s eyelets.
Worn-out plastic rim tape can cause flats on its own due to the formation of sharp edges.
What Is The Function of Rim Tape?
Rim tape’s function is to act as a protective layer separating the rim from the inner tube. Without rim tape, the edges of the spokes’ eyelets can pierce the inner tube.
How To Prevent Flats Caused By Rim Tape
1. Remove the tire to see if the rim tape is properly seated. It should be centered and cover all spoke holes.
2. If the rim tape is worn out or too narrow for the rim, you will have to replace it.
How Can I Know If The Rim Tape Is The Source of Flats
There are three main indications pointing towards “rim-tape-induced” flats:
1. You’re getting multiple flats during the same ride without finding a sharp object in the inner tube or tire.
2. The rim tape is flimsy and doesn’t cover the spoke eyelets.
3. The tape is plastic and has a pointy edge (usually near the area where both ends connect).
When To Replace Rim Tape?
Quality rim tape can last years. If you’re getting flats from “invisible objects”, however, the rim tape could very well be the source of the problem.
Back when I was just starting my bike commute journey, I got a few flats in one day before finally realizing that the problem wasn’t an external object but the wheel itself – the rim had sharp edges barely covered by a very thin and rubbery rim tape partially torn at places.
Upon replacing the rim tape with a wider one and of better quality, the problems stopped.
If you’re not getting flats, the rim tape on your wheels is probably fine. Nonetheless, it’s worth inspecting it before a long trip or a race. If the tape is visibly worn, replace it.
Note: If you have a fairly inexpensive bicycle, chances are that the manufacturer has put the cheapest possible rim tape.
To reduce the chances of getting flats, you could consider replacing the rim tape right away or upon getting the first flat regardless of its source.
Is Rim Tape Necessary For a Tubeless Set-up?
Tubeless rims do not have spoke eyelets on the inside and therefore do not need rim tape.
If the rims are tubeless-ready, then they have spoke holes on the inside and require the use of tubeless rim tape that seals the entire rim and prevents the sealant from leaking out.
Unlike regular rim tape, tubeless rim tape is thinner has adhesive on the back.
Can I Use Tubeless Rim Tape With Tubes?
Tubeless rim tape can be used with regular tubes. One can even argue that it’s is better than standard rim tape thanks to the adhesive which prevents movement.
However, if you intend to run high PSI (air pressure), consider wrapping two layers of tubeless rim tape over the rim.
This is done to ensure that the inner tube doesn’t push through the tubeless rim tape which is often a bit thin.
Can You Reuse Rim Tape?
If the integrity of the tape hasn’t been compromised, it can be reused.
Nonetheless, if you have new rims, it’s advisable to buy new rim tape for them.
Can You Patch Rim Tape?
If the rim tape is worn at specific locations, you can patch it via electrical or duct tape.
For the best results, it’s recommended to cover more than the affected area. For example, if you want to patch 2cm, patch 5-10cm.
Alternatively, you could wrap tape over the entire rim and make a small hole for the valve.
This method isn’t ideal because other parts of the tape may tear in the recent future.
Given the relatively low price of rim tape, it’s best to replace it with a new one. Nonetheless, a patch could work for a surprisingly long time.
Frequently Asked Questions
What Rim Tape Do I Need For 700c Wheels?
The rim tape that you need is determined by two factors:
- The size of the wheel;
- The inner width of the rim;
If you have a 700c wheel, you need 700c rim tape of width equal to that of the inner rim or a bit wider.
For example, if the inner width of the rim is 18mm, search for rim tape that’s at least 18mm wide.
If that’s not available, go for the closest larger size (e.g., 20mm). It’s better to go up rather than down to maximize the coverage.
If you don’t know the inner width of your rim, you can easily measure it with a ruler or a caliper. Alternatively, you could also search for the rim’s specifications online.
Can I Use Electrical Tape Instead of Rim Tape?
Electrical tape can work as a temporary patch placed over the current rim tape, but on its own, it may be too soft and stretchy to sustain high air pressure.
The risk of electric tape failing is greater with double-wall rims because there’s a chamber formed by the two walls.
Under high pressure, the electric tape could move and allow the tube to penetrate the space between the two walls. The end result will be a puncture. To reduce the chances of that happening, it’s recommended to apply more than one layer of tape.
The likelihood of a similar scenario is lower with single-wall rims because in that case, the job of the rim tape is solely to protect the inner tube from the sharp edges of the spokes. There is no chamber that the tube can penetrate.
Another downside of electric tape is that it leaves a sticky residue that requires a lot of effort to remove. This could be annoying when replacing a spoke.
Can I Use Duct Tape Instead of Rim Tape?
Using duct tape as rim tape seems to be common practice. Even some mechanics in bicycle shops do it.
That said, duct tape has the following downsides when applied as rim tape:
1. Inability to sustain high pressure. The constant pressing of the tube against the duct tape will eventually push the tape into the spokes’ eyelets.
If you use duct tape long enough, you will clearly see the places where the tube has been pushing against the tape.
2. Potential instability. The chances of the tape moving augment in hot weather because heat tends to have a negative effect on the adhesive.
3. It’s sticky. Just like electric tape, duct tape leaves a sticky layer. This could be an annoying inconvenience when relacing the wheel.
4. Expensive. Quality duct tape will end up being more expensive than actual rim tape.
I want to use duct tape as rim tape despite its downsides. How do I cut the tape to the necessary width?
Step 1: Determine the inner width of the rim.
Step 2: Mark the width on the duct tape roll. You can add 1-3mm for extra coverage.
Step 3: Place a utility knife on an object elevating the blade by an amount equal to the width that you want to cut.
Step 4: Press the blade against the roll of tape.
Step 5: Begin rotating the duct tape roll while holding the utility knife firmly. (Make sure that your fingers are far away from the blade. Utility knives cut quick and deep.) Keep cutting until you have the desired length.
Can I use two rim tapes for extra security?
You could, but if the rim tape that you have is of decent quality, a single unit is enough.
Is There An Alternative To Rim Tape?
Even though rim tape is the standard there are other products that can accomplish the same goal. One of them is VeloPlugs – little plastic caps that go into the eyelets of the rim and cover the rough edges.
The advantages of VeloPlugs is that they are lighter than rim tape and don’t move out of place.
How Can I Remove Rim Tape Residue From My Rim?
Isopropyl alcohol a.k.a. rubbing alcohol is a popular choice for removing the sticky residue. It’s good for cleaning other parts of the bike too.
WD-40 is also effective for adhesive removal.
Note: After applying WD-40 you will have to use another degreaser to remove the WD-40 remainings.
My rim tape is fairly new, but the ends have detached from one another. Is this a problem? Any fixes?
Regular rim tape stays on by fitting tightly around the rim and squeezing it. There’s no adhesive that keeps the tape on.
You may be able to install the tire even when both ends of the rim tape are disconnected, but the rim tape will be moving all over the place.
To fix this, you can sew the rim tape’s ends to one another while respecting the original circumference of the rim tape. If you make the rim tape too narrow, you won’t be able to install it on the wheel; if it’s too broad, it won’t fit tightly.
For sewing, you can use dental floss as it’s very strong.
It’s recommended to cover the tape with one roll of electric tape to reinforce it and protect the tube from the patched spot.
Note: If you use a cord or very thick liner, it may pierce the tube, especially if you don’t add the reinforcing electric tape.
