Knobby tires are not for loose gravel roads?

Afan

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I always thought that off-road riding "requires" off-road tires. At least 90-10%. I know you can have simple off-roading on the street tires - I did it several times, on my Pilot Road 5, but you know what am I talking about...

By the way, just to clarify, I'm totally newbie in off-road riding, and all my off-road riding was actually gravel riding (I'm from Iowa :D). And if I put all numbers together, I don't think I rode in total more than 60-70 miles. No experience whatsoever. And all of my "off-roading" I did on my NC700X - never rode a dirt or dual-sport bikes.

Last weekend I made a trip to Villages of Van Buren, and took gravel roads along the Des Moines River. The gravel roads from my last weekend trip were ok.

20190720_102935.jpg

I read many articles and watched many YouTube videos how to ride on gravel roads and it helped me. Didn't have a lot of trouble - until I hit a VERY LOOSE, probably recently poured gravel section, shy of 7 miles. I was horrified! It looks like the loose gravel was extra loose. I was dancing left and right. I almost crap myself. The worst experience ever.

Anyway... When I got home next day I did research again about the riding on, and tires for extra loose gravel - and found that actually off-road, knobby tires do not help much on loose gravel roads - if not even make it worse.

"... The truth is that on gravel, knobs don’t make any difference. Without semi-firm ground to dig into, knobs can’t do anything. When you slide, it’s because gravel is sliding on gravel, not because your tires are sliding on the top layer of rocks..."
- Why We Don’t Make “Gravel” Tires | Off The Beaten Path

Ok, this is from bicycle website (because nothing similar didn't find on motorcycle websites), but the same principles apply, right? And when you watch off-road tire reviews, the knobies are actually linked to mud, sand, fire-roads, single lane roads, and gravel "in general"...

The main reason why am I writing all this is because couple days ago I found the Shinko 705 front tire in the "original" size (LINK) and it's pretty narrow. I was thinking to order it, but I live in Iowa, and I'm pretty sure 90% of all non-paved roads are actually just (loose) gravel roads. So, if I kinda didn't have trouble with "just" gravel roads, hard packed roads on my PR5, why then should I buy narrower tire and crap myself on next loose gravel road?

Comments?

P.S. One thing actually I forgot on my trip was to air down the tire pressure. Just simply forgot. Probably would help a bit...
 
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670cc

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I’m confused on one point. You mentioned that you looked at Shinko 705 stock size and it was “narrower”. Narrower than your PR5? Is your front PR5 some size wider than the stock size?

I wonder if you’re misled by the tire photo on the tire vender website. The photo I see on the americanmototire site shows an example of a 705, but is obviously not the actual size in the listing for the 120/70-17, or else the dimensions in the photo are distorted.

As I mentioned before, I used a 705 in the stock front size, and I found it to grip better on variable, loose, unimproved road surfaces. Sure, I could ride a street tire in that case also. No tire works perfect on all surface types, but subtle differences in the grip on variable surfaces when using the 705 over a street tire seemed to inspire more confidence.
 
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Afan

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I’m confused on one point. You mentioned that you looked at Shinko 705 stock size and it was “narrower”. Narrower than your PR5? Is your front PR5 some size wider than the stock size?
I wonder if you’re misled by the tire photo on the tire vender website. The photo I see on the americanmototire site shows an example of a 705, but is obviously not the actual size in the listing for the 120/70-17, or else the dimensions in the photo are distorted...

Yes, I have to confess, the photo mislead me. And, for someone who works 8:00 - 5:00 building websites - pretty embarrassing, isn't it?

View attachment 38711

My PR is the same (original) size and it never occured to me that "1 lbs of lead weights the same as 1 lbs of feathers"... :(

... As I mentioned before, I used a 705 in the stock front size, and I found it to grip better on variable, loose, unimproved road surfaces. Sure, I could ride a street tire in that case also. No tire works perfect on all surface types, but subtle differences in the grip on variable surfaces when using the 705 over a street tire seemed to inspire more confidence.

I totally agree that there is no tire for all situations (that's why I never buy "all season" tires for my cars) but the reason I posted this was: if I would spend most of my off-road time actually on the Iowa's famous loose gravel roads, and knobby tires don't work well on the loose gravel - why bother with 50-50% TKC-80 or similar tires, right?!? Of course, if I plan to ride some beautiful Colorado roads it would be totally different story...

As you said, Shinko 705 should be fine. :)

Thanks.
 

670cc

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Afan

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The americanmototire web site is not clear on the tube vs tubeless for this tire, so I looked at the Shinko USA site: 705 Series Tire - Shinko Tires. It shows the front 120/70-17 size as available only in tubeless. When you get the tire, the tube and/ortubeless application type will be stamped on the sidewall.

View attachment 38713

Happy news. Prefer tubeless. More "convenient" ;)
:D

Thanks, I appreciate it.
 

Jt105

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I’ve noticed that riding gravel with a street tire that is almost bald (worn past the wear indicators) is like riding on marbles. When I put a new set of PR4s on, the difference was like night and day... much better.
I also rode a bike with knobby tires. At normal speeds, it performs like the street tires. At fast speeds, the knobby tires were much better.

It depends on where you ride and the road surface. Most gravel roads around my town are dirt and gravel packed down pretty hard with some loose stones. This type of gravel is pretty easy with most any motorcycle.
I have ridden roads where it was inches deep loose stones and that was horrible with a motorcycle. Anything bigger than a light dual sport bike would have a problem no matter what tires you have.

JT
 

Rapturee

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Hey Afan, i too run a 120/70-17" Shinko 705 on the front, (i also have a 140/80-17" Shinko 705 in the rear). Coming from Conti-Motions it was a nice change for dirt/gravel/rocky roads that i like to ride. Even with airing the Conti's down, the 705's are hands down better! My first ride with the new 705 on the front , (to scrub it in ya know), was a nice 200 mile ride that included 35 miles of rocks, gravel, terrible marbles, huge potholes, washouts and 7 really cool old tunnels! For long distance gravel roads i have found that lowering the air pressure in both tires makes a nice difference as well. I normally run 36f/42r on the street and 24f/28r(depending on load carried) works really well for me. It only takes a couple of minutes to air them back up once i hit the pavement with the little "slime" air pump that i carry in the frunk. However, if i'm only going a short distance(couple of miles) then i will not change the air pressure in them at all.

new shinko 705 installed2 at 12922 miles on front July 7 2019.jpg
 

Junkie

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Hey Afan, i too run a 120/70-17" Shinko 705 on the front, (i also have a 140/80-17" Shinko 705 in the rear). Coming from Conti-Motions it was a nice change for dirt/gravel/rocky roads that i like to ride. Even with airing the Conti's down, the 705's are hands down better! My first ride with the new 705 on the front , (to scrub it in ya know), was a nice 200 mile ride that included 35 miles of rocks, gravel, terrible marbles, huge potholes, washouts and 7 really cool old tunnels! For long distance gravel roads i have found that lowering the air pressure in both tires makes a nice difference as well. I normally run 36f/42r on the street and 24f/28r(depending on load carried) works really well for me. It only takes a couple of minutes to air them back up once i hit the pavement with the little "slime" air pump that i carry in the frunk. However, if i'm only going a short distance(couple of miles) then i will not change the air pressure in them at all.

View attachment 38728
was your ride on an old railroad bed?

FWIW if you want a wider front tire, you can run the 130/80 705 up front. It's quite a bit taller too, and will require raising or removing the fender.
 
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