
Jim’s Tech Talk
By Jim Langley
It’s said that timing is everything. So you could say that we blew it on this product reveal – since it was last week and the one before that we were focused on tubeless tire troubles and triumphs.
The thing is that we didn’t realize our friends at Park Tool were enjoying our tubeless series and had decided to surprise us by sending over their new TSI-1 Tubeless Sealant Injector (thanks Park Tool crew!). And since it’s still a dead heat between road tubeless proponents and opponents that have written in, we figure at least half of you will appreciate knowing about this new tool.

Designed to Avoid the Mess
When setting up road tubeless tires with sealant you might have a bottle with a pointed cap that lets you squirt it into the mounted tire through the valve (you first must remove the valve core). That’s a nice way to do it that reduces the risk of sealant spills.
If you don’t have that type of sealant bottle/container, the other way to insert the goop is by leaving a few inches of tire off the rim and pouring the sealant into the tire. When you insert the liquid this way, there’s more risk of a spill since you have to then finish installing the tire onto the wheel.
Skilled sealant technicians can use either approach without making a mess. But, for the rest of us it’s easy to get it wrong. If the pointy end of the bottle slips out of the valve for example. Or if you thought you had your partially installed tire on right and it wasn’t. Once the sealant’s in it, if it pops off the rim, watch out!

Injectors Contain the Mess
The advantage of an injector like Park’s TSI-1 is that they hold the sealant inside and provide control over how much is installed and removed. It’s a large injector, too, holding 3.5 fluid ounces (100 cc) of sealant and with a 4.75 inch long (120mm) straw/needle to fit down into most tires.
Made of a super heavy-duty clear plastic with easy to hold oversize handles, the TSI-1 has a gauge on the side showing the amount of sealant. The plunger is oversized and operates very smoothly. The straw is removable for easy cleaning – and you must clean the syringe and straw after each use with soap and water to keep it functioning properly.
For Removal, Too
Injectors don’t just inject. They extract sealant, too. And getting old sealant out of a wheel can make even a bigger mess than putting it in. With Park’s injector, you can pull it out of the valve the same way you put sealant in. That way when you remove the tire, it might still be a little wet inside but you won’t get soaked. (You can also remove sealant with the injector from a tire that’s partially removed.)
The suction of the plunger keeps the sealant inside the injector, too. So unlike an open bottle or container that can tip over, once the sealant’s inside the TSI-1 it will stay there until you put new sealant back in the container or dispose of the spent stuff.
Verdict
Park’s TSI-1 is a handy tool tubeless riders will appreciate and get a lot of use out of. The only thing that would make it better is if it somehow had a built-in valve core removal tool since the tools are used together.
Park’s TSI-1 sells for $25.95. https://www.parktool.com/product/tubeless-sealant-injector-tsi-1
Here’s a video to see it in action:
Jim Langley is RBR’s Technical Editor. He has been a pro mechanic and cycling writer for more than 40 years. He’s the author of Your Home Bicycle Workshop in the RBR eBookstore. Check out his “cycling aficionado” website at http://www.jimlangley.net, his Q&A blog and updates at Twitter. Jim’s cycling streak ended in February 2022 with a total of 10,269 consecutive daily rides (28 years, 1 month and 11 days of never missing a ride). Click to read Jim’s full bio.
I use Orange Seal sealant 4 oz. bottle that comes with an injector tube. The 4 oz. bottle is easy to determine If I want to use 4 oz. in my mtn. bike tires or 2-3 oz. in my road bike tires. It also comes with a handy sealant measuring dip stick to check sealant level. I like the Orange sealant better than Stan’s stuff. I personally haven’t had much luck with Stan’s sealant such as wheel damage.
Thanks for sharing your tips, David!
Jim
I carry a 2 oz. bottle of sealant. A valve core, and a valve core removal tool. The sealant bottle has a spout designed to fit in the valve stem. So there isn’t a need to carry a special injector tool. However, I will probably will order the Park injector tool for home use. The Park injector appears to be to bulky to carry in a jersey. I have many Park tools all of great quality and highly recommend them.
Thanks for the feedback, Rick. I think you’ll like this Park injector for home use a lot.
Jim
I’ve used several different methods for adding sealant to tubeless tires. I purchased one of these a while back and recently had a chance to use it for the first time (converting the wheels on my brand new Stumpjumper — yay! — to tubeless). It was the easiest, cleanest, and most accurate (in terms of volume added) of any of the methods I’ve used. It didn’t hurt that these particular tires were the absolute easiest I’ve ever mounted (Specialized Purgatory and Butcher). I was able to do it with just my floor pump — first time ever in many years of riding tubeless (only on my MTB and gravel bike — not ready for the road bike)! Now, this had nothing to do with the injector — it would have done its job the same regardless of how difficult the tires were to mount. But the joy of such an easy mounting job transferred right over to the use of this well designed tool…