Suspension vs big volume tyres

[lulubel]

I recall someone saying (possibly on this forum) that the most important suspension system on a MTB is the bit between the wheel and the ground.

Yet, there's tons of material on the internet about the relative merits of different suspension forks, long travel or short travel, whether HT or FS is better, etc. There seem to be a lot of people out there who believe suspension, in its various forms, is not only nice to have, but essential, if you want to ride certain trails. (My obsession with buying a bike with RS Reba forks came about as a result of reading all this stuff.)

But is it essential? What is the difference between suspension (front and/or rear) and running great big, fat tyres?

That's the question in a nutshell. There's more detail below (and some personal stuff) if you want to read it ...

The reason I ask this question is because touring has long been a goal of mine, and since I've fallen in love with MTBing, I think I'd prefer to tour with a MTB (rather than my Surly CrossCheck, which was supposed to be my tourer), so I can take time to explore the rough stuff during my travels. My Cube isn't ideal for touring because, apart from its very limited water carrying capacity, the front end lifts easily without a heavy load on the back (I would want to carry camping gear), and although I understand you can get a rack to mount on suspension forks, it isn't ideal, and I wouldn't want to risk damaging my lovely Rebas. So, for touring, I'd probably get a Surly Troll frame, and move everything from my Cube (apart from the forks) over to it.

Of course, this would leave me with rigid forks, which are great for road and fine for smooth trails, but possibly not so much fun when it gets rough and rocky. I'd want to use "roadified" tyres for travelling between places, and carry a set of knobblies to put on when I find a place I want to stay for a while and do some proper off-roading. (Knobblies being slower on the road, and I wouldn't particularly want to wear the knobs off them by covering big distances with a heavy load.) How viable would it be to run something like a 2.2 on the back with something considerably wider on the front? How much would a high volume tyre make up for the lack of suspension forks?

This is all (hopefully) very long term for me. At the moment, I can't even go out for more than 2-3 hours on the bike because I have a very sick cat at home. He was diagnosed back in April with a brain tumour that we think is benign, although it does seem to be growing. Physically, he's not too bad, although he does have balance problems, but it's the behavioural changes it's caused that are most difficult to cope with. He's generally quite happy as long as I'm nearby, and he's fine with my OH looking after him if I go out for a couple of hours, but he goes into a complete panic meltdown if I'm gone for too long. (It's a good thing I'm self-employed and work from home.) So, there will be no touring for me until the time comes when he doesn't need me any more, at which point I may go into a complete meltdown and be very anxious to go off on my bike and lose myself for a while. Hence, I'm trying to make some plans now.

 

[RecordAceFromNew]

But is it essential? What is the difference between suspension (front and/or rear) and running great big, fat tyres?That's the question in a nutshell.

A friend of mine is a sponsored rider of one of the manufacturers. He regularly rides (and does) what is shown below (i.e. with no suspension). His tyres are like 24x55. The bike has no brakes, yet he can stop on a tuppence even in the rough (braking is usually achieved by jamming foot between saddle and rear wheel and/or spinning the bike around). Last time I rode with him he wheelie down nearly the whole of Whitehall on just his back wheel.

So the answer is definitely, resoundingly, no.

But then he has more steel pins in him than I would like to contemplate. I suspect it is easier to achieve similar with shocks.

 

[Motozulu]

Hey Lulu - as a kid we had a family cat - his name was Oscar and he was immense - I saw him chase dogs ten times his size from our front lawn and I was proud of him, he was a total nutter. His tumour killed him in the end, I had to take him to the vets for the coup de gras - I blarted like a babby,

Pets should be banned.

 

[lulubel]

Thanks, guys.

Yes, I know it's possible to do all sorts of stuff with rigid forks. I suppose I'm really asking to what degree high volume tyres make up for the loss of suspension forks.

Moto, he's my baby. I found him (he was dumped as a kitten) when I was in a very bad place emotionally, and he gave me something to live for. I'm truly dreading the day when I have to carry on with life without him.

 

[Norm]

Suspension or fat tyres are there to keep the rubber in contact with the ground as much as possible. For significantly off road stuff, fat tyres will not be able to maintain that contact with the ground the same way that suspension forks can. Even the fattest tyres won't deform much more than 15-20mm (although tubeless and lower pressures might double that) so any bump more than that and they'll be airborne the other side until gravity spots you and drags you back down again. And, unless your tyres are flat, there's little sag in them so almost any drop or step down will have air under your wheels for a time.

So, whilst I agree with RecordAce that suspension is not essential, and I get that from personal expense as I've taken my CX bike on some pretty rough off road rides, I think that suspension is both more comfortable and safer when you are riding through heavy duty lumpy stuff.

However, and as a slight aside, how extreme are you thinking? I see that you are contemplating taking tyres with you as well, so I'm guessing your thoughts are pretty hard core. My Tricross, nominally a CX bike, makes an excellent tourer and, as I said above, has been on some mucky and lumpy trails without changing anything from standard, not even the tyres. If they are good enough in the mucky stuff (and you can see how smooth they are in the middle in the pic) to manage the bike without a sliding in these conditions, I'd be happy to use them as a one-stop choice on a tour.

 

[Crackle]

Can't tell you, I still don't have anything but a rigid mtn bike. I'm quite happy doing red trails on that and an occasional beyond, subject to bravery on the day, rather than suspension and the few times I did hire a bike with suspension, I noticed the geometry differences more than the suspension. Being able to get the front end up and hop the bike more easily was the biggest difference.

You do feel it on uneven surfaces though, the vibration can blur your vision, which suspension solves, largely, and you can rely on it to compensate for a bad line, which all means I tend to be more cautious on downhills.

As for tyres, dunno. Pressure differences in the 2.5's make a difference to grip and comfort but I'd still like suspension rather than buying bigger tyre's. One thing about my rigid bike is it can be used on the road and copes well. It has quite a stretched riding position for a mtn bike and I've used it as a tourer but with a change of tyres. My son's mtn bike has a hybrid tyre with a central ridge, OK for easy off road. My other son's bike has Rockshox air forks and that's what I want next, they're superb.

 

[lulubel]

However, and as a slight aside, how extreme are you thinking? I see that you are contemplating taking tyres with you as well, so I'm guessing your thoughts are pretty hard core. My Tricross, nominally a CX bike, makes an excellent tourer and, as I said above, has been on some mucky and lumpy trails without changing anything from standard, not even the tyres. If they are good enough in the mucky stuff (and you can see how smooth they are in the middle in the pic) to manage the bike without a sliding in these conditions, I'd be happy to use them as a one-stop choice on a tour.

Thanks, Norm. You've raised another point there that hadn't occured to me.

All my focus so far as a MTBer has been to get the best setup for the trails near home, which are typically dry, strewn with loose rock in a wide variety of shapes and sizes, and very steep in places. I hadn't thought about the high likelihood of encountering mud on my travels!

I currently ride a pretty aggresively styled XC hardtail with 100mm air forks. Despite my best efforts, I haven't managed to use more than 70% of the available travel yet, so my fork setup obviously needs some tweaking. I have 2.2" Conti Mountain King tyres front and rear (presumably so named because they're targetted at riders tackling a lot of mountains) and they do seem to perform very well on the kind of terrain I encounter. I run my tyres extremely soft (with tubes) at 10f/14r, and have been as low as 8f/12r. The guys on here have suggested I get away with this because I'm very small and light and take sympathetic lines.

The Surly Troll frame can take up to 2.7" tyres, but I think that's probably a bit more extreme than I need. I could certainly go up to 2.4" or 2.5" on the front if it would make the bike handle better. I'm mostly concerned about keeping control on long, steep, bumpy descents because it's easy enough to just take it a bit steadier on the flats if you need to.

My problem is that I see a track winding away into the distance, and I want to see where it goes, especially if it goes straight up a mountain! I never know what I'm going to find in the way of trail conditions until I get there, although I'm not averse to getting off and walking/carrying the bike for a bit if there's a short section that isn't passable any other way.

For the actual touring part, I'd be looking at using narrower semi slicks for less rolling resistance on the road, but still grippy enough to tack the Spanish "unmade" roads that you come across quite often around here, and presumably in other parts of Spain as well.

 

[shouldbeinbed]

another consideration is how fast you'll be travelling over the grimpy stuff. Bombing over it at olympic downhiller speeds will see the tyre airborne; even just a little way; far more often and you'll benefit much more from having suspension than sedately picking your way across it just quick enough not to fall off.

 

[lulubel]

Can't tell you, I still don't have anything but a rigid mtn bike. I'm quite happy doing red trails on that and an occasional beyond, subject to bravery on the day, rather than suspension and the few times I did hire a bike with suspension, I noticed the geometry differences more than the suspension. Being able to get the front end up and hop the bike more easily was the biggest difference.

You do feel it on uneven surfaces though, the vibration can blur your vision, which suspension solves, largely, and you can rely on it to compensate for a bad line, which all means I tend to be more cautious on downhills.

As for tyres, dunno. Pressure differences in the 2.5's make a difference to grip and comfort but I'd still like suspension rather than buying bigger tyre's. One thing about my rigid bike is it can be used on the road and copes well. It has quite a stretched riding position for a mtn bike and I've used it as a tourer but with a change of tyres. My son's mtn bike has a hybrid tyre with a central ridge, OK for easy off road. My other son's bike has Rockshox air forks and that's what I want next, they're superb.

I totally agree on the RS forks. My Rebas are so lovely (but I was replacing worn out, cheap forks, which I think give less control than rigid, so it's hardly a surprise I feel that way).

It's actually interesting that you only ride rigid. Most of what I ride on around here is probably the equivalent of red trails, with some easier stuff, and the occasional bit of hard stuff thrown in. I suppose one way to get an idea how it would feel is to get a wider tyre, stick it on the front and ride with the suspension locked out, although I appreciate there's still some movement even in locked out forks.

I do know that I really notice the difference between 10 and 15psi in the front tyre, even with the suspension forks, so I suspect I'd notice it again with more air between the wheels and the ground.

I haven't actually bunny hopped the MTB yet, although I have lifted the front wheel, mostly unintentionally, before I learned how to not do that! But I can bunny hop my road bike without any problems, so I don't think the lack of suspension would be a problem there.

 

[lulubel]

another consideration is how fast you'll be travelling over the grimpy stuff. Bombing over it at olympic downhiller speeds will see the tyre airborne; even just a little way; far more often and you'll benefit much more from having suspension than sedately picking your way across it just quick enough not to fall off.

I'm not fast, by any stretch of the imagination. I'd rather be laughing than wondering whether I'm going to get to the end of the trail alive.

 

[lulubel]

Reading through your replies, and doing a bit more research, has made me realise there's a choice to be made. I can either focus on touring or MTBing, and the more I focus on one, the less suitable the bike will be for the other. Trying to go for the middle ground will mean I end up with a bike that isn't really great at either.

Going rigid - and steel - with huge water carrying capacity (the 2013 Troll has 5 sets of bottle cage mounts) is definitely focusing on touring, and the MTBing side will suffer. If I'm going to go down that route, I might as well just accept that I'm not going to have masses of fun off-road and tour on the Crosscheck instead.

The alternative choice, focusing on the MTBing side of things, means moving away from the whole racks and panniers idea and towing a trailer instead.

At the moment, the trailer is looking like a much better option. Yes, there are disadvantages (having a trailer with you on tour isn't always convenient) but the big advantage is that I don't have to change anything about my Cube. I can just get a suitable trailer, attach it to the back and go. And not having to buy a whole new frame will save me more money than I need to spend to get a good trailer, so I'll have more money to spend on good quality camping gear. And another advantage is that I can unhitch the trailer, swap the tyres over, and I immediately have a proper MTB, one without racks that doesn't look like it's a heavy tourer pretending to be a MTB.

I've done a bit of research into my water issues as well (which are less of an issue when you consider I can just carry water on the trailer to top up my drink bottle), and I spotted someone using a custom made frame bag that fills the space in the main triangle and carries a water bladder. I've got plenty of imagination and my OH has a sewing machine I can borrow, so I'm sure I could design something similar for my Cube that would take 1.5 - 2l of water. This is a great winter project for me, in any case, because I'd like to carry more water for my normal rides in the summer. On tour, I'll also have other options for saddle/seat post mounting of water bottles, once the stuff I usually carry there is relegated to the trailer.

Good idea? Bad idea? Is there something really important I've overlooked?

 

[Crackle]

I think the trailer idea combined with the Cube sounds like a good plan. I've seen people towing trailers on easy off road stuff as well, such as forest tracks and byways. I think the Troll is probably a bad, or less than ideal idea.

Are there any downsides. Well, as I said before, I've used my mtn bike for touring but it has a different geometry to your Cube. I guess travelling speed will be a bit lower and the all round position is not as ideal as an out and out tourer, especially if you hit a headwind, no hunkering down. Hand positions are limited for road riding, which can get uncomfortable, bar ends maybe. Likewise the saddle may be great for one activity but not ideal for another. So all of that combined with a more upright position and the general geometry, may fatigue you a little sooner than a tourer but a lot will depend on your personal comfort and endurance levels and how far you intend to go each day.

 

[zizou]

You don't need suspension to ride trails but having it sure helps make things a bit more pleasant and less physically demanding too (particularly on the upper body). It is also a good skills compensator, if i pick the wrong line on my 140mm fs then i can often still ride where i'd be falling off on my rigid bike

For touring off road then i'd go rigid, not only is it going to be a more sedate style of riding, be better for load carrying but there is reliability to consider too with a rigid compared to a suspension fork. I think the Surley Pugsey would be my ideal bike for off road touring, seen a couple of great threads on other forums of people mtbing and pack rafting with them. http://forums.mtbr.com/passion/alas...-bar-hopping-fishing-extravaganza-434649.html

btw I wouldnt worry too much about only using 70% of your travel so far, for typical xc riding i never use the full amount on my bikes unless doing a drop or a jump. You want that final 20 - 30% to be there when you need it rather than use it all the time.

 

[Rohloff_Brompton_Rider]

Try googling bikepacking, a new way to tour or s24o.


http://www.bikepacking.net/

http://www.alpkit.com/bikepacking

Photos here...

http://www.flickr.com/groups/ultralightbiking/pool/with/8128386318/#photo_8128386318

 

[GrumpyGregry]

When someone ordinary on a rigid bike rides the black at. say. Antur Stiniog in something vaguely resembling the time taken by someone of equal skills on an AM or DH bike, and can walk talk and chew solids afterwards the argument will be over.

As for RecordAceFromNew's pic; Martyn Ashton could, no doubt, do that on a road bike. Not sure what either situation is meant to prove.