As bikers, sooner or later, we’re going to get stuck with a tire puncture. When you have the privilege of lane sharing, it can be even more common because cars aren’t keeping that part of the road free from debris. I’ve used the mushroom style plugs and the sticky-rope-glue style plugs, and I find the sticky rope style last longer. The mushroom style plugs seem to come loose after a day or two, so while I still have a kit for it, I only use it for temporary fixes when I’m out on the road. So let’s talk about plugging a tire.
Yes. Yes, I know. I’ve heard all about how plugging a moto tire is bad. How I’ll lose control and die in a firery crash. Yes. I know. Guess what? I have plugged a couple tires and never died in a firery crash. Shocking, I know. This very same tire picked up a nail when it had 200 miles on it. Yes, 200. I’m not replacing a tire after 200 miles if I can help it. Below is a picture of that plug after 4800 miles.
All this to say, be smart about plugging a tire; you shouldn’t plug in the sidewall, or anything even close to the sidewall. In my case, I’ve only plugged in the meat of the tire tread. As always, don’t tech over your head. If you’re not sure what to do or if the plug is a good choice, talk to a professional.
In my most recent situation, a neighbor’s contractor spilled a shit ton of screws and nails all over our street. We all leave for work before the sun is up so no one noticed until we all had screwed up tires. Wife’s car had five in one tire, three in another. All told eight cars on my street needed new tires. Luckily the Ducati only picked up one, but I didn’t realize it until a couple days later when my rear was 50% down from the day before. This tire has 5,000 miles on it and I know a plug will hold so I’m plugging it.
Remove and Clean
The first step is to get the spike out of the tire. If you’re on the side of the road stuck without a plug kit, you can put some spit on it to see if it’s leaking, at least to get to a gas station or something. If you’re on the side of the road, especially alone, it can be challenging, but use whatever you have to get it out. Needle-nose channel locks work pretty well, but I don’t have any so I pried it out with a flat head screwdriver.
You can find a plug kit at any auto parts store or mega-box store. They’re pretty much all the same and come with the same stuff – a rasp, a tool to set the plug, some plugs, and some glue/cement. Once the object is out, use the rasp to clean the hole. This can be tough because the hole won’t always be perpendicular to the tread. That was the same case with this bolt, it was at about a 45 degree angle.
Carefully insert the rasp through the same hole the bolt made (don’t make a new hole!), then push/pull the rasp to clean and smooth the hole. This is the physically hardest part of the operation. If you have a riding buddy, have them hold your bike while it’s on the side stand.
It’s a little easier with a paddock stand, like this Pitbull I’m using. I give a few push-pulls until the rasp moves in/out pretty smoothly. Note: It can be really tough to get this going if the hole is right on a belt and the rasp has trouble smoothing it out.
Setting the Plug
Get the inserting tool, not sure exactly what it’s called, and thread one of the sticky ropes 50/50 through the tool. They’re a little naturally sticky, and you want to try and keep it as clean as possible. Try to not drop it in the dirt on the side of the road.
Get the glue from the kit and liberally coat the rope with glue, full length of the rope and all around, as much as you can. You don’t need to go crazy with it, but I’ve had the best luck with fully coating the whole thing.
Now the part that will make or break the repair: setting the plug. Line up the tool with the hole, getting as close to the same angle as possible. The tire will have no air, probably, so pushing it will compress the tire making it tough to get started. In my experience it will suddenly jump and insert itself so be ready for that.
This kit said to push it about 2/3’s in, but it just ended up where it ended up. Once you get it in, pull the tool back out in one smooth quick motion – DON’T TWIST. Twisting will pull the plug back out, and possibly ruin the rope. It’ll pull out probably easier than you think.
When you pull it out, some of the rope will be sticking out, that’s normal. You might see a weird looking bump under the skin of the tread, also normal.
Use a razor or sharp knife and cut off the nub of the plug, as flush with the tread as possible. If a little is stuck out, no worries. Riding on it will smash it down and it’ll smooth out over time (see picture above). The glue may take some time to completely dry and will remain sticky, so don’t be surprised if you see sand and grit stuck to it. I’ve never had any problem.
Fill the tire with air, cross your fingers, and then get some window cleaner or spit over the plug and look for any bubbles generated around the plug. If you see bubbles, good news – you get to try it again. If no bubbles, it’s plugged and seated itself well. Personally I let mine sit for a while to let the glue set up, and then I diligently check the tire pressure for a couple days. In the event the plug leaks a little, try riding on it in town and let the heat/pressure make the glue flow and the plug to form into any gaps in the hole. Even the 200 mile plug I did leaked a little, but after a day or two it didn’t leak at all.
Congrats – you did it. If you ride far from civilization, you probably want to carry a flat repair kit with the air cylinders. If you’re a saddle/tank/tailbag kind of guy, it’s a good idea spend the money on one of those small air compressors. Again, be smart. Not every tire can be fixed with a plug – the best way is with an internal patch, but you can’t really do that on the side of the road. If you’re not sure if the repair is safe, talk to a professional.