Mountain Bike Reviews Forum banner
1 - 20 of 32 Posts

·
Registered
Joined
·
280 Posts
Discussion Starter · #1 ·
I wandered away from the computer during July and returned to find a 29x3 tire. Thank you Surly. I have SnowCats and think it could be fun to run a snow bike on the new tires.

I know the tire guys on this forum have run the numbers so what is the trade off if you go 29x3?

Thanks.
 

·
Administrator
Joined
·
11,315 Posts
I wandered away from the computer during July and returned to find a 29x3 tire. Thank you Surly. I have SnowCats and think it could be fun to run a snow bike on the new tires.

I know the tire guys on this forum have run the numbers so what is the trade off if you go 29x3?

Thanks.
Right now I think the main problem is that it is only available on complete krampi. No spares yet, so tear a sidewall and you are waiting until the next run of tires. So buy a complete and ride it carefully.

I will let others chime in on the other stuff.
 

·
Registered
Joined
·
473 Posts
Right now I think the main problem is that it is only available on complete krampi. No spares yet, so tear a sidewall and you are waiting until the next run of tires. So buy a complete and ride it carefully.
You have that backwards, and the completes aren't available yet.

Frames, tires and rims are supposed to be available in December.

Completes are supposed to be available in March.
 

·
Registered
Joined
·
473 Posts
Rabbit Holes are pretty much the same weight as Marge Lites, and the Knard is 400-700 grams lighter than a 26er fat tire, so one benefit would be a lighter wheel.

Prices on 29+ rims and tires are comparable to 26er fatties.

I'd be most interested in seeing is how the size/shape of the contact patch varies.
 

·
Registered
Joined
·
179 Posts
I'd be most interested in seeing is how the size/shape of the contact patch varies.
Well it's going to be longer and narrower.

Just looking at outside tire diameters (29 vs 30.5) I would guess the 29+ contact patch would be about 5% longer. Comparing the tire widths assuming their contact patch width is about their casing width 3.7 vs 3.0 you'd be looking at around a 15% reduction in surface area with a 29x3.0 vs a 26x3.7.

Of course tire pressures and a million other things are going to effect this too but I suspect that a 29x3.0 will have at least a 15% reduction in contact patch area when compared to a 26x3.7. I suspect the 29x3.0 will actually require a bit higher tire pressure for riding and the contact patch will shrink quite a bit more.

The high volume 26" tires are still going to be the go to option for flotation but for trail riding 29+ will bring some of the nice bump absorbing steam rolling ride characteristics of the big rubber with a bit more nimble handling.

My $0.02
 

·
Registered
Joined
·
128 Posts
I agree with woodi2259.

Pugs- Mud, Snow, Sand

Krampus- hardpack trail, gravel, etc.

Obviously you will be able to use either bike for pretty much anything, but I think each one will excel in things the other doesn't.
 

·
Registered
Joined
·
14,417 Posts
You have that backwards, and the completes aren't available yet.

Frames, tires and rims are supposed to be available in December.

Completes are supposed to be available in March.
What I've read online is that the frames will be available this fall and they'll only sell tires/rims with a frame as they have a limited amount. So you get enough to build up a Krampus.

Eventually you'll be able to buy rims/tires a la carte, but no clear idea when that will be.

Completes are supposed to come out next spring as you note.
 

·
Recovering couch patato
Joined
·
14,017 Posts
I agree with above.
But like to add that when going into 26x4 territory (sand, snow), I suspect the 29+ will have the advantage for higher speeds. Like a fit rider amking serious ground VS a traveller making its way to the next camp site. I've found that I could get quite a bit of sand performance from basic 1kg 29x2.35 Big Apple tires, as long as I was pushing the pace. I was comparing to much lighter racer types (I'm an XL guy and not skinny), main difference was rim diameter. 29x3.0 is going to make such a difference. More float, still fast. A better allrounder I think, just less of a crawler.
And lighter, how about that?
 

·
Registered
Joined
·
7,386 Posts
The effect of this tyre size is going to be interesting. The 3" tyre has roughly 66% more volume than a 2.35" so it should absorb more of the trail irregularities.

I'm happy to ride fat all year round rather than consider using my 29ers, (summer = bog in Scotland :) ) but for many fatbike riders this may be the ideal summer tyre for fun singletrack. If I can squeeze it into one of my 29ers I may try it - it will give some purpose to the piles of expensive dust collectors in my shed. Otherwise I'll stay fat. I think it's going to lead to the redesign of a lot of existing 29er frames when it catches on.

It's about time the other mtb tyre manufacturers woke up to what is happening outside the confines of the skinny mtb tyre competition crowd.
 

·
Registered
Joined
·
473 Posts
...but for many fatbike riders this may be the ideal summer tyre for fun singletrack.
I agree 100%, and I'm planning to be one of them.

I got a chance to ride a Krampus yesterday and it was pretty freakin' sweet. Unfortunately it was a large (20"?) with a really short stem; it was way too small for me. I only rode about 3.5 miles, but it's fun, flowy singletrack with a hardpack tread and some sandy/loose sections. I then rode the same trail with my fat front Fargo.

The Krampus had a great feel to it. I should say I don't ride a "normal" 29er off-road, so I can only compare it to my fat front set-up (heavy DH Large Marge, 1st generation Larry and Surly tube)...

It was noticeably faster than my fat front Fargo. The Krampus rolls REALLY well. The Krampus front end felt just as smooth as my fat front, but the rear end felt significantly smoother. Great grip in the loose corners, on par with my fat front with even more traction in the back.

A Rabbit Hole/Knard will be my next wheelset, without a doubt. I'll run them on my fat bike for the time being, but after riding a Krampus I think a 29+ frame will (eventually) replace my fat front Fargo.
 

·
Registered
Joined
·
7,386 Posts
More thoughts:

A Krampus rear plus a fat front sounds like a good mix to me. I find the skinny 29er wheel feels like it momentarily hangs up on stuff the fat front steamrolls over.
 

·
Registered
Joined
·
3,330 Posts
Role on March, I love riding rigid most of the time, couldn't get enough float with a 26" 3" Savage tyre + 29mm Rim, couldn't run them soft enough and they measured as a 2.7" for me anyway on that rim.

So the 29er advantage for roots and rocks and roll speed + proper 3" + 50mm rim sounds great to me.

The outter diameter will likely be the same as the standard fat tyre ofcourse.

Got left for dead in the mud by a nutter on a Surly 1/2 fat today, I could see what line he was taking through mud and basically straight through the middle barely leaving a mark on the mud, smart.

Would that tyre fit in a 29er carbon exotic fork ?? if so where can I get the wheel and tyre from / and fork if needs be ??

Any idea on costs ??
 

·
Registered
Joined
·
3,330 Posts
Thats 2"'s bigger than a standard 29er with a 2.25 tyre that is some serious role over diameter..

Role on March, shame it won't be in time for the winter gloop unless I DIY it or maybe go 1/2 29erfat ( 26" rear ).
 

·
will rant for food
Joined
·
3,996 Posts
I got to demo a Krampus very briefly today (mile and a half?). It was fun.

The idea that it floats like a fat bike? Nope. Was able to get squirrely in some sand.

However, the tires are fun and big. I ran mine at "I have no idea" PSI, on dusty hard pack. Given that I rode it such a short distance, all I can say for sure is that it corners very well and complains less than my fat bike off camber (!), rolls forever, and is generally well mannered. The name 29+ is very appropriate.

I'd want one with a suspension fork, but that's just me, I want a full suspension fat bike so take it with a grain of salt. At any rate, the tires, at first blush, appear to be exactly what they look like: a really big 29er tire that you can deflate a bit, trust in the corners, and coast a long way.

The frame itself: not much crazy going on aside from the chain stay yoke, and even that looks more sane in person than in photos.

I want one. Next summer for me, out of being optimistic that snow will actually fall here this season.
 

·
Registered
Joined
·
130 Posts
ftmn/ drew diller

can you confirm if the seat tube and seatpost of the krampus29+ is different from their other frame offerings, more specifically, is the seatpost still 27.2?

looking at pictures, it appears to be different, more like 30.9 or something

thanks

bb1
 

·
Registered
Joined
·
591 Posts
The Krampus front end felt just as smooth as my fat front, but the rear end felt significantly smoother. Great grip in the loose corners, on par with my fat front with even more traction in the back.
Thanks for the review, FTMN. What was the tire pressure? Were they set up tubeless?
 
1 - 20 of 32 Posts
Top