Tire sizes?

Tbone

Member
I'm confused about tire sizes. Currently running 27.5x2.35 - 650B razor rock (knob) tires. I want to replace them with Super Moto-X tires. Will 27,5x2,80 (70-584) fit?
Thanks for info.

-T
 

David Berry

Well-Known Member
Tom, Schwalbe's Super Moto-X (70-584) should fit just fine on your rims (584x35C); however, whether these much wider tyres will leave sufficient clearance between fender and/or stays is doubtful.

Although the Super Moto-Xs are nominally 10 mm wider, they will have a rounder profile. My guess is that there won't be sufficient despite not having the knobs to rub agains the fender!

Suggestion: Consider the narrower Super Moto-X (62-584) – still 2 mm wider than the Rock Razors (60-584) but without knobs to get in the way of fenders.

I've assumed that your ebike is an R&M Charger GX fitted with Rodi Tryp 35 rims.
David
 
Last edited:

Tbone

Member
Thanks for info. I've since measured a bit more and you're definitely right. And now I know the significance of tire width, which had me all confused. Would appreciate any other suggestion regarding moving from knob tires to more street/trekking tires? I ride 60/40 (street/off-road) and feel its about time to get away from the knobs but still need something that will work off-road. What about those so-called "snake skin" tires I'm seeing?
 

David Berry

Well-Known Member
I've been trying out various Schwalbe options on my 2019 Homage GX Rohloff:
  • Marathon Plus MTB (57-584) with tubes,
  • Rock Razor (60-584) tubeless with Finish Line sealant,
  • G-One Allround (57-584) tubeless with Stan's sealant.
Verdict? Not yet.
 

Tbone

Member
I'm leaning toward the Super Moto-X (62-584) you also recommended. Main reason is their wear rating--according to the dealer I'm buying them from. They are supposed to last longer than rock razor or g-one. I'm also unfamiliar with tubeless tires. Guess I'll have to read up on that. Thanks for your help!
 
And now I know the significance of tire width, which had me all confused. Would appreciate any other suggestion regarding moving from knob tires to more street/trekking tires? I ride 60/40 (street/off-road) and feel its about time to get away from the knobs but still need something that will work off-road.
First, note that tire widths are nominal and actual tire width will vary. To compound matters, rim width and inflation pressure also affect actual outside tire width. This article talks a bit about sizing. I've read some tire reviews where they've measured tires and they were quite off from the printed tire size (sometimes narrower than stated).

FWIW, here's a thread on a mountain bike forum asking about Super Moto-Xs for on and orff use, with one poster claiming that Schwalbe itself recommended Rocket Ron Liteskins instead, and another poster confirming that. These aren't electric bikes, so they cared a lot more about weight and rolling resistance.

I've been considering the Smart Sam Plus since it has a row of closely spaced knobs down the middle, which should help with on road performance while still having lots of knobbies for off-road. But, I have no data to back this up.
 
I've been considering the Smart Sam Plus since it has a row of closely spaced knobs down the middle, which should help with on road performance while still having lots of knobbies for off-road. But, I have no data to back this up.
Actually, I just found that Schwalbe's own page on the Smart Sam's says:
The compact central rib provides comfortable rolling; the edged outer lugs guarantee optimized off-road-grip. For this reason Smart Sam is reliable in every condition and even rolls well on roads.
The "plus" version has more puncture protection, but has less available sizes.
 

Alaskan

Well-Known Member
I really like the Schwalbe Smart Sam HS 476 (27.5 x 2.6) Double Defense Dual which is also available in 2.25" just slightly narrower than the tires that came on your bike I put them on my Delight Mountain as they have the good balance between road-grip, off road-grip, protection and durability. They have a nearly continuous center tread that gives them reduced rolling resistance on paved surfaces and nobbies on the side for unpaved. I have put 2,000 miles on them at this point and am quite pleased with them.

 

rich c

Well-Known Member
I run Supermoto X on my Haibike Full Seven. When I go on technical trails I lower the air pressure. That really increases the grip. We’re not allowed to ride there when it’s muddy, so they work extremely well and no need for knobbies.
 

Mr. Coffee

Well-Known Member
Another thumbs up for the Smart Sams.

I ride a lot on atrocious roads and they are a great tire. My only very mild complaint is that they have a tendency to "wash out" on tight corners at speed.

Any and all kinds of flat protection offered with a bicycle tire is generally a Good Thing.
 
I really like the Schwalbe Smart Sam HS 476 (27.5 x 2.6) ... I have put 2,000 miles on them at this point and am quite pleased with them.
Great info - thanks! Some questions:

1) Do you run them at different pressures on-road versus off-road, or just a single pressure (numbers)?
2) How are they on wet pavement?
 

Alaskan

Well-Known Member
Great info - thanks! Some questions:

1) Do you run them at different pressures on-road versus off-road, or just a single pressure (numbers)?
2) How are they on wet pavement?
The Delight has a full suspension so I do not rely on the tires to soften the ride for me. I keep them at 45 psi most of the time but will take them down to 25-30 when I am spending the day off pavement

They seem good, not great on wet pavement.
 

Tbone

Member
Great info - thanks! Some questions:

1) Do you run them at different pressures on-road versus off-road, or just a single pressure (numbers)?
2) How are they on wet pavement?
I tested the rock-razor's with different pressures at first but found them to be unstable with low pressure on pavement. After that I never felt like bothering with air pressure. I've been running them ever since at around 3-3.5 bar for all surfaces--a bit hard at times but so is the hardtail of my charger gx. The air forks, btw, are only "soft" when on extreme off-road surfaces. All in all, with these pumped-up mountain bike tires, my bike is set to hard, very hard.

The rock razor's are not good on wet pavement. I've had a number of issues in the rain with them. They're especially scary in the fall with leaves and wet weather. Off-road, as best I can tell, they are pretty good. I never thought I'd go over 8000km with these tires--but I'm now ready to switch up. (Btw, I'm on my second rock razor rear, having changed it at around 5000km.)
 

Tbone

Member
FYI - Received the super Moto-x tires this morning, even though I thought they wouldn't arrive till next week. Installed them right away. First impression after a short test ride in the rain? Yeah, baby. Should've done this a long time ago. Charger GX has been... urbanised. Review coming soon.