Knobby Knife?

[GMP]

Anyone use one? Tires are getting too expensive, especially with kids riding now.

 

[andykr87]

Ive had good luck with mine. Pays for itself quick. Need to plug it in and let it get to full temp though. Doesnt work good unless you do that.

 

[mcnut]

My neighbor bought me one because I'm always working on his trails for him. It works pretty good. Takes a little practice and patience if you want your tire to look nice when your done. You can even use it for some funky cut patterns like the endurocross guys do.

 

[GMP]

Sounds good, think I'll get one soon. I've used a disc grinder (smokey and messy) and a hacksaw sharpened into a long razor on a grinder(easy to ruin tire). Neither result was pretty.

 

[Elvis74]

I use a cheaper version
a chisel like this
http://www.yagma.de/media/images/popup/22000023021.jpg
and a flame

 

[gasser]

These work well. The first one they sent me would not get hot enough to work properly but their customer service is great - one quick call and another tool was on its way with a free knobby knife tee shirt and I didn't even have to return the first tool.

 

[jaysktms]

Well worth the money, can keep the edges sharp for one more ride. At most you can cut a tire twice. Does take a little practice.

 

[jostby]

Sounds good, think I'll get one soon. I've used a disc grinder (smokey and messy) and a hacksaw sharpened into a long razor on a grinder(easy to ruin tire). Neither result was pretty.

back when I rode trials I used to use a razor blade to square up the edges and even siped the knobs before the manufacturers started selling them that way. That sucked (serious finger cramps). But it worked

My riding buddy has a hot knife. Works well.

 

[houndog]

Just saw this. Couple weeks ago ran into the local "kid" (fast as Hell) racer. He looked at my tire and said "you need a "knobby knife" (may not have used that exact name). I had no idea....he explained it was an electric hot knife, really sharp to "repair" a worn tire. He pointed to his rear tire.....damn thing looked "new" except with really short knobs. Knobs had sharp edges and groves very deep. He said it takes practice and is time consuming but worth it. He said it allows him to use his "practice" bike" tires a lot longer. This kid is good and fast and not rich. I trust him and planned on getting one....the 450 sort of eats tires. I'd like to keep the knobs sharp for as long as possible.

I meant to find out more about them, (price, vendor, etc.) but forgot until I saw this thread. Heading to "google" now..................

Ed

 

[(F5)]

You should find easy + you tube demos.

I find I sharpen mine every so often just a few rubs on sandpaper. Some tyres are easier than others, but it extends the life & means you can ride on sharper edges toward the end of tyre life.

 

[GMP]

I got one and practiced on an old tire, then my kids tire. I learned that you have to look closely at the face of the knobs in relation to the base, and cut the same angle, not straight down. Don't take two much of a bite, it doesn't cut well if its too thick. I did an MT-16 before my last race and it seemed to work OK.

 

[(F5)]

Just realised my post looks like I sharpen the tyres with sand paper.

I meant the knife section should be touched up with sandpaper on a flat surface & rubbed as you'd sharpen a knife (if people still did that).

 

[forgiven]

Glad you said that...I was wondering...sandpaper...really...

Doesn't that clog up??