IRC m5b 140/80 v 120/80

[brute448]

which ever i get will be for a 15' 450 xcw.  all research says 140/80 is good for 120/100 and 120/80 is good for 110/100 < same as stock.  there is the 130/80 which i assume is the tween'er.  I liked how the 110/100 at 81 handled and such but its slimey in oreogn now so badass m5b is up next.  I want the 140 for most situations but i'm doing first hare scramble at washugal on jan 1. and think the quick/ lighter rotation of the 120 would be better suited.

 

now ladies and gents may I get your thoughts?

 

thank U!

[Slippy McSavage]

the 140 is going to get you that "BITE", which i think may slow you down in a race. the 120 m5b is significantly smaller though. i dont see any reason to go down to a 120 other than weight and wanting some wheel spin. the 130 is also, imo, significantly smaller but still offers a lot of traction when new with a little slip. when mounted on rims and put next to each other the 140 clearly stands out.

 

are you using a UHD tube and two rim locks or a tubliss set up?

Edited November 12, 2015 by TheW0LF

[woods-rider]

In my experience, the 140s catch the chain and chunk off the left side knobs almost immediately. Also, A super wide tire will "float" more in mud which can be good and bad. Sometimes you need the tire to "slice" through the top mud layer to get down to the tackier dirt to get good drive. I have tried 140s in the past and prefer 120s in the summer and 130s in the winter for Western Oregon.

 

The last tire I ran was the M5B and it was straight up awesome. It's only downfall for me is its weak carcass since I run Tubliss. The carcass wore out quickly (I was running around 3-4 psi) and it started to puncture often. For use with a tube and more standard pressure (18-15 psi) I think this would be my tire of choice for western Oregon winters.

Edited November 12, 2015 by woods-rider

[Slippy McSavage]

In my experience, the 140s catch the chain and chunk off the left side knobs almost immediately. 

 

not saying its not true, but this is the first i have heard of this happening. i also run my chain a little looser than spec, but ive never had any issues with chain slap/rub.

[woods-rider]

not saying its not true, but this is the first i have heard of this happening. i also run my chain a little looser than spec, but ive never had any issues with chain slap/rub.

 

Yeah, it may not be a common issue, but it happened with two different 140s on my 2006 WR450.

[Slippy McSavage]

Yeah, it may not be a common issue, but it happened with two different 140s on my 2006 WR450.

 

yea ive never had an issue and my whole group runs the 140 on their ktm's. as for the wr though, i have no experience with it. a few of our guys have the carb'd wr450's, but i cant say if they are running the 140 or 130 m5b.

[brute448]

the 140 is going to get you that "BITE", which i think may slow you down in a race. the 120 m5b is significantly smaller though. i dont see any reason to go down to a 120 other than weight and wanting some wheel spin. the 130 is also, imo, significantly smaller but still offers a lot of traction when new with a little slip. when mounted on rims and put next to each other the 140 clearly stands out.

 

are you using a UHD tube and two rim locks or a tubliss set up?

 

Im running standard tube (same that came w/ bike in may). I plan to swap into tublis and run shinko 520 once this tire wears out in the spring

 

**seems as though ill be ordering the 140/80-18

Edited November 12, 2015 by brute448

[BillDirt1]

which ever i get will be for a 15' 450 xcw.  all research says 140/80 is good for 120/100 and 120/80 is good for 110/100 < same as stock.  there is the 130/80 which i assume is the tween'er.  I liked how the 110/100 at 81 handled and such but its slimey in oreogn now so badass m5b is up next.  I want the 140 for most situations but i'm doing first hare scramble at washugal on jan 1. and think the quick/ lighter rotation of the 120 would be better suited.

 

now ladies and gents may I get your thoughts?

 

thank U!

I favor the 140/80/18.

[Slippy McSavage]

Im running standard tube (same that came w/ bike in may). I plan to swap into tublis and run shinko 520 once this tire wears out in the spring

 

**seems as though ill be ordering the 140/80-18

 

i was looking at the shinko 520. havent seen it in person, but the side knobs look like they are going to shave right off. center knobs look great though. gonna be tough to beat the tried and true m5b.

 

give the 130 a try. brand new its gonna work just as good as the 140, maybe better turning. its once it get a little worn, you might see some differences. let us know what you think.

Edited November 12, 2015 by TheW0LF

[brute448]

copy that! ill judge the 140 vs 130 on pricing when i order next week.  Woods-rider is running the shinko 520 w/ tublis and he runs like 4 lbs. ill let him elaborate on wear, but seems like a good tire, also Jeff Slavens preaches the 520 as well,< thats y i want to get on it, but tublis will have to wait till spring.

 

thanks all!

[woods-rider]

Wear on the Shinko 520 has been excellent thus far. I have about 25 hrs on it and it has about 80% knob height and absolutely zero chunking and no punctures (knock on wood). All trail use with minimal connecting gravel roads and zero pavement. I also haven't used it in a high speed desert scenario (and won't since I have multiple rear wheels, one of which is my desert setup). I won't know how the carcass is holding up until I dismount it which won't be until the knobs are significantly worn or until I start getting a lot of punctures. So far it's my rear tire of choice when running Tubliss.

Edited November 12, 2015 by woods-rider

[Dansmith1965]

In my experience, tire size doesn't matter much. It's all about the tire's intended use and tread pattern. For example, I was nervous about loosing bite when I went from my 140/80 6 days to a smaller 120/100 maxxis desert IT. It was just the opposite. The desert IT bites like crazy in every terrain I've touch so far (no street yet), way better than the 140/80. The bike still seems to turn the same and handle the same, but it really hooks up.

So in my case, a thinner tire meant nothing.

Edited November 12, 2015 by Deepseadan

[Slippy McSavage]

Wear on the Shinko 520 has been excellent thus far. I have about 25 hrs on it and it has about 80% knob height and absolutely zero chunking and no punctures (knock on wood). All trail use with minimal connecting gravel roads and zero pavement. I also haven't used it in a high speed desert scenario (and won't since I have multiple rear wheels, one of which is my desert setup). I won't know how the carcass is holding up until I dismount it which won't be until the knobs are significantly worn or until I start getting a lot of punctures. So far it's my rear tire of choice when running Tubliss.

yea it looks like it would work well. i run the m5b with an UHD tube and 2 rimlocks, often times 2-3psi cold and sometimes flat for really big hillclimbs. works outstanding and you know how the wear is. when the center knobs of the m5b flatten/round off, the big side knobs compensate. one scenario i see the shinko falling short is on steep side hill switchbacks with worn center knobs. those small side knobs will rip off when weight and power are put directly on them. i think the shinko will work great when its new, but i think the m5b will work well longer solely based on its side knobs.

 

im totally open to trying that shinko though. 

[Slippy McSavage]

In my experience, tire size doesn't matter much. It's all about the tire's intended use and tread pattern. For example, I was nervous about loosing bite when I went from my 140/80 6 days to a smaller 120/100 maxxis desert IT. It was just the opposite. The desert IT bites like crazy in every terrain I've touch so far (no street yet), way better than the 140/80. The bike still seems to turn the same and handle the same, but it really hooks up.

So in my case, a thinner tire meant nothing.

 

as im sure you know, each manufacturer measures tires a little differently. a 120 could be just as big or bigger than a 140 between separate manufactures. 

[Dansmith1965]

as im sure you know, each manufacturer measures tires a little differently. a 120 could be just as big or bigger than a 140 between separate manufactures.

I did measure the two tires and the 120 was a bit thinner, but a lot taller.

[woods-rider]

IMO the M5b had better traction when new than the Shinko 520, but the wear on the Shinko is superior to the M5b. Neither tire chunked for me, but the knobs on the M5b wore a bit faster than the shinko and the carcass was JUNK after about 15 hrs.I am pretty sure that the quick carcass wear  was due to the low pressures that allowed the carcass to flex a lot.

Edited November 12, 2015 by woods-rider