Bicycle Seat Condom




During the Fall semester I started riding my bike to school and learned I hated riding in the rain after a seven hour class. I dreaded the idea of riding in the rain with a wet bike seat causing me to stand while pedaling. Luckily, being surrounded by Low density polyethylene (LDPE) cutoffs in the studio I began experimenting with vacuum forming this material to create a reusable bicycle seat cover that is durable, flexible, and waterproof.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: Materials Needed


1 Sheet of LDPE (Low density polyethylene) cut to designated size of a vacuum former
Here is a link on information about LDPE

2 Sets of Grommets

1 Bungee Cord

1 Marker (Erasable markers work the best

1 Vacuum Former
Here is a link to make a good, cheap, upgradeable sheet vacuum former

Scissors and Razor Blade

Step 2: Step 1: Retrieve Bike

Step 1: Retrieve your bike and bring it into a safe clean area.

Step 3: Step 2: Remove Bike Seat

Step 2: Locate your bike seat and remove it from the seat post.

Step 4: Step 3: Find Vacuum Former

Step 3: Locate a vacuum former and place the seat at a diagonal on the tray. The placement of the bike seat on the vacuum tray will help keep the seat from moving and displace the LDPE better.

Step 5: Step 4: Warm Vacuum Former

Step 4: Turn on the Vacuum former and allow it to warm up. REMEMBER to keep the bike seat tray down while the warming up to keep bike seat from melting.

Step 6: Step 5: Forming the LDPE

Step 5: When the LDPE is soft enough remove the heating component and raise the vacuum bed. REMEMBER to remove the heating component

Step 7: Step 6: Helpful Hint

Step 6: Turn the vacuum on an off in short bursts to allow the LDPE to form around the seat without tearing. The LDPE is soft when warm which will may cause a hole from the force of the vacuum.

Step 8: Step 7: Marking

Step 7: Allow the LDPE to cool and remove the tray. Draw a line around the seat with an erasable marker. (Hint: Erasable markers are the best)

Step 9: Step 8: Cutting and Attaching Grommets

Step 8: Cut out the LDPE using scissors and a razor blade. I like to use small scissors at the end to cleanup my cuts. Draw marks in the center of the seat and attach the grommets. When grommets are attached hook your bungee cord to the grommets and give a slight pull to test for tearing.

Step 10: Congratulations

Congratulations! You have successfully made a Bike Seat Condom. Go outside and ride in the rain with your new creation.

Epilog Challenge

Participated in the
Epilog Challenge

Be the First to Share


    • Made with Math Contest

      Made with Math Contest
    • Cardboard Speed Challenge

      Cardboard Speed Challenge
    • Multi-Discipline Contest

      Multi-Discipline Contest

    46 Discussions


    3 years ago

    It took me a few seconds before i figure it out that giant seat doesn't belong to the next bicycle and its just a regular seat with a close up photo :DD

    IDK if anyone understands me! :DD


    6 years ago on Introduction

    I did almost the same thing to protect my leather seat. I used styrene, because that was what was easily accessible. However, it doesn't last when cold: mine cracked when I used it in the winter. Who knows, maybe it was just ready to crack and temperature had nothing to do with it, but this is Winnipeg and it does get cold, and I ride through the winter. So, how is your cover holding up? Have you used it in cold weather? Maybe I just need to get myself some LDPE. Or if not that, anyone have suggestions for a good thermoformable winter plastic for this?


    8 years ago on Introduction

    You know those plastic grocery bags? One of those and a rubber band. Also works when transporting bikes on the auto bike carrier. I keep one rubberbanded to the stem.

    1 reply

    Reply 8 years ago on Introduction

    I like to keep a neatly folded plastic bag wedged between the saddle & the rail. No need for a rubber band & its always there when I need it. I prefer the black bags, they're pretty much invisible since my saddle is black as well.


    10 years ago on Introduction

    Two alternatives to this 'solution': 1. Stick a hand-towel in your bag to wipe water off a wet seat. 2. Remove the seat from the bicycle when not in use. This also has the effect of deterring theft.

    4 replies
    bad ass popetchiseen

    Reply 9 years ago on Introduction

    Taking your seat off is a baad idea. You'll just get a load of rainwater and therefore rust inside your frame, which isn't cool, believe me.


    Reply 9 years ago on Introduction

    I third, motion carried.  everyone,  "Don't Panic"... oh and so long and thanks for all the fish


    9 years ago on Introduction

    Why not just use a few actual condoms, one over the other? Several people on youtube have stretched the things over their heads, so getting one over a bicycle seat shouldn't be a problem. Also, having a rubber on your bicycle that looks like it has been used for something nasty (which it will after a short ride) would be a great theft deterrant. Alternately, there exist waterproof neoprene covers that stretch over a seat rather like a condom does a male gizmo... I got mine for free at the seattle bikeswap, and it's kept my Brooks dry and happy ever since.


    10 years ago on Introduction

    Is it just me or did anyone else notice that this person talks about riding"in" the rain with a wet seat? I find it odd that they dont mind getting wet everywhere else from the rain but they need to have a dry butt. strange.

    2 replies

    Reply 9 years ago on Introduction

    If you'd ever ridden on a wet seat you'd understand that it sucks to have your pants soaked through. Besides, a jacket and whatever helmet/hood+rain pants type combination you happen to have will keep you mostly dry, but the bike is only protected once you're actually on it. Actually, rain pants do double duty by keeping you insulated from your seat's wetness and stopping the water from the road and the sky from hitting your pants, but this is about seats....


    9 years ago on Introduction

     Anyone else just use a shower cap? It's like they were made for it. Plus, they're much easier to store.


    10 years ago on Introduction

    +1 who thought this was going to be "put condom on bike seat, ride bike, optionally slip off seat".

    3 replies

    Reply 10 years ago on Introduction

    Ditto. In fact, I was already trying to remember where I put the condoms since it seems like it will work. (I got this free showercap-thingy that does the same, but I think a condom would be good alternative if ever it gets taken.)


    10 years ago on Introduction

    wow!¬¬! I made this kinda job whit rc car body shells!=P

    but i never think to make this to mi bike...


    I'll try this=D