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OffRoad How Do u Sipe Tires?

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Since a trials tire is not allowed in the Erzberg, i was thinking of siping my Pirelli MT 16 rear tire. Any Advice? Any idea if minor siping on the front is beneficial? I have a Knobby Knife and a Ideal Heater Knife (made for Siping) but i am having a hard time finding and choosing tips and blades.

SigetyErzberg_JPG_highrez.jpg

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Never heard of siping a motorcycle knobby but....

On auto tires siping is just razor cuts across the tread. Starting 1/2 in from the outside edges and spacing the cuts about 1/4 inch apart you make cuts straight across the tire.

I have used this in the winter and had much improved traction on ice and snow. The cut sections open and act like little fingers when torque is applied to the tire. Not sure what dirtbike environments it would help with? Maybe slick rock?

If I were applying this method to a dirtbike knobby I would probably leave the outside knobbies alone and sipe the inside/center knobbies. A utility knife might work just fine. You don't want to go too deep or the knobbies might just disintegrate during wheel spin. Maybe 3/8 or so deep? Make as many cuts as needed across each knobby to give you that 1/4 or so spacing.

I don't know the benefit of doing this but I would certainly try it on a tire here and not wait until race day to see what happens to the tire as it could just shred the knobbies with lots of wheel spin.

Can you run any tire other than a trials tire? Does it have to be a FIM approved tire?

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Sigety, I have a knobby knife and haven't so much as siped it from left to right,but actually put big deep x's in the front and back tires on my wr450 on some kenda trakmasters. Makes a huge difference in traction, but will also cause your tire to chunk off if you are riding rocky places. I just mounted a mt16 yesterday to try. Next is a set of studs. JLow. By the way, i am super duper jealous, good luck.

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Thanks for the advice and offer, I have the Knobby knife and the Ideal tire groover / siper. I haven't siped yet either and plan to try it soon. I need to order some tips and blades, the ones that came with it are huge! Wasn't their an article in one of the mags showing how the Endurocross boys siped their tires?

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I tried this on a Bridge404. Traction was awesome. Tire lasted about 30 mins before some much of the knobbies were missing it was useless.

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I tried this on a Bridge404. Traction was awesome. Tire lasted about 30 mins before some much of the knobbies were missing it was useless.

How deep into the knobbies did you cut?

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um, it was about 1/8-1/4 inch cuts.

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I've siped front and back tires, 1/4" sounds about right. Make sure you sipe along the longitudinal axis of the tire on the front, otherwise the knobs will chunk bad when you brake hard. Tires felt a lot more stable in the turns, seemed to have tons more traction.

I grooved the rear, laterally, and it worked well. Seemed to have better traction across the board. I siped the rear also and it destroyed the center knobs, I wouldn't recommend siping the rear.

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I grooved the rear, laterally, and it worked well. Seemed to have better traction across the board. I siped the rear also and it destroyed the center knobs, I wouldn't recommend siping the rear.

Is thier a difference between grooving and siping?

Also, does anyone know what aizw tip and blade i should order? I assume the smallest is a number 2 for an Ideal Heated Knife

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Grooving is putting new tread in a bald(ish) tyre.

Siping is putting very thin cuts into a tread block so it effectively becomes a collection of smaller, more supple blocks.

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Is thier a difference between grooving and siping?

Also, does anyone know what aizw tip and blade i should order? I assume the smallest is a number 2 for an Ideal Heated Knife

I used a buddies 250w ideal groover with a .250 head. The blades were fine, you just have to be careful not to cut too much off the lugs. If you want to sipe, just turn the blade upside down in the groover.

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Is thier a difference between grooving and siping?

In my neck of the woods if someone asks for a groover, they will receive a bucket to take a crap in. :thumbsup:

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Thanks Dr Gonzo!!!! I was looking for that exact picture! I wonder if those siped knobs will be an issue in the sand hill climbs?

141_0912_15_z+EnduroCross_Factory_Bikes+rear_tire_grooves.jpg

141_0912_27_z+EnduroCross_Factory_Bikes+dunlop_geomax_MX51.jpg

141_0912_39_z+EnduroCross_Factory_Bikes+pirelli_tire.jpg

FYI these are the pics from Enduro Cross

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Never siped a moto tire before, but have siped tons of dirt late model tires. Those are grooves in the pics, not sipes. You can only see sipes if you are very close. Sipes are done with either a siping tool that holds razor blades, a tool that holds a grooving blade that is turned over, or a tire groover with the heat off and the blade turned over. Never more than 1/8 deep and never too close to the edge of the tread blocks or they will chunk to quick. Check out somewhere like speedway motors for examples of different siping tools. good luck.

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Yep thts not siping, thts grooving. Sipes are shallow and narrow, grooves can be narrow or wide depending on which wire you use. I do my race tires, it is a big help but the tire wnt last long. IMO i dnt do the very outside row at all and have gone to every other center lug. Traction is improved quite a bit. I will post a pic of my tire after a H/S, this was a fresh tire the race was 2 1/2 hour on moderately rocky terrain with good sized hill climbs.

http://s1086.photobucket.com/albums/j456/HeidiCC/

Hope this helps, I'm a pretty big fan of grooving tires, they just don't last long. That tire is a MX51.

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On 5/11/2011 at 7:38 PM, Live To Ride Mike said:

Thanks Dr Gonzo!!!! I was looking for that exact picture! I wonder if those siped knobs will be an issue in the sand hill climbs?

141_0912_15_z+EnduroCross_Factory_Bikes+rear_tire_grooves.jpg

141_0912_27_z+EnduroCross_Factory_Bikes+dunlop_geomax_MX51.jpg

141_0912_39_z+EnduroCross_Factory_Bikes+pirelli_tire.jpg

FYI these are the pics from Enduro Cross

Bump... going to do this on my tire today 

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