Carbon or Alloy MTB for a fat git?

[DJFish]

I'm looking to buy an MTB, currently torn between a Scott Scale 950/960 & a Whyte 629.
However my head has been turned by a Cube Reaction GTC which is currently on sale and appears to be a bit of a bargain, it has lots of XT kit on it but has a carbon frame.

I'm not going to pretend to be that good a rider that I'll ever notice the subtleties of feel between an Alloy or carbon frame, I'm more concerned that when I plonk my salad averse arse on the saddle it's going to fall to bits like a clown car at the circus.

I've never owned a carbon bike so I'm worried about longevity and having to treat the thing with kid gloves....

[neenaw]

DJFish said:

I've never owned a carbon bike so I'm worried about longevity and having to treat the thing with kid gloves....

I wouldn't be worried at all about whether it's carbon or alloy, get whichever's most comfortable and fits your budget.
I've got carbon framed bikes and they've had quite a bit of hammer and I can't say that it's ever crossed my mind to be worried because they're carbon.

[Jag_NE]

im not at my optimum weight also and I was looking at some new bikes recently. I presumed that until you lose the timber from your body its probably a bit pointless spending a lot of money to save a little bit of weight on the bike frame? I am very much a novice so stand to be corrected here....

[P-Jay]

Some makers do have maximum rider weights buried in their small print on their websites.

Lapierre used to state 100Kgs I believe, that seems a bit low especially since they make XL frames, it's more of a cop out really though.

I really wouldn't worry about it, MTB frames are very strong and robust these days, they all fear a 'Crack n' Fail' type scandal - if your memory doesn't go back that far, Cannondale was one of the biggest names in the industry for years and years until some of their frames started to break in the early 2000s I think, it (along with trying to make an MX bikes) nearly sunk them, they recovered but have never really got back to the very top tier of desirability .

[DJFish]

Smashing,
I'm going to find one to test ride & see if I like it.
I'm not really interested in it because it's carbon, just the fact that it's a really good deal with a good spec...

[P-Jay]

Jag_NE said:

im not at my optimum weight also and I was looking at some new bikes recently. I presumed that until you lose the timber from your body its probably a bit pointless spending a lot of money to save a little bit of weight on the bike frame? I am very much a novice so stand to be corrected here....

Depends where the weight is (on the bike, not the body) most frame and component weight is just weight - lighter is generally faster, but if you're 120Kgs there's little point spending £100 more to save 35g of derailleur weight. Wheels are the obvious exception - lighter wheels are quicker to accelerate and makes the steering quicker, but you need to spend fortunes to make a significant saving - we're in the age of the £2k MTB wheelset.

Saying that, lighter wheels aren't always better anyway, lighter might mean weaker until you spend a lot, but more importantly gyroscopic effect is a big part of what makes a bike do, what it does - reduce rotational weight and you lose some of it, it can make bikes feel nervous over roots and rocks unless you're used to it.

Whether there's any point, for me it doesn't make much sense if you're 50% lard or have the body fat of a pencil sharpener - you can get a great bike for a fair price these days, or spend many multiples more to get ones that's a bit better.

I was looking at the new Intense Tracer yesterday (silly expensive bike) the "cheap" one is £4000, the bling one is £10,000. I would bet the fancy one is less than 5% faster with any rider, up or down, in any conditions.

[Mr Gearchange]

DJFish said:

I'm more concerned that when I plonk my salad averse arse on the saddle it's going to fall to bits like a clown car at the circus.

I've never owned a carbon bike so I'm worried about longevity and having to treat the thing with kid gloves....

Don't know why people have these concerns - carbon fibre is a lot stronger than either aluminium or steel - which is why they use it. Better resistance to just about any force you'll ever put on a bike

Ive got 2 aluminium bikes and and a carbon bike - the carbon bike is a 210mm travel DH rig - I'm not worried about sending it off anything.

ETA This is an interesting video that should alleviate any concerns - particularly any around impact.

https://www.youtube.com/watch?v=xreZdUBqpJs

Edited by Mr Gearchange on Thursday 9th February 16:14

[anonymous-user]

Wheels will most likely be your biggest issue if you're a big lump.

I broke my 2013 Rockhopper wheels in less than 30 miles, and broke them again and again so had a custom set made up for about £400 from DCR Wheels.

[DJFish]

Mr Gearchange said:

Don't know why people have these concerns - carbon fibre is a lot stronger than either aluminium or steel - which is why they use it.

Ive got 2 aluminium bikes and and a carbon bike - the carbon bike is a 210mm travel DH rig - I'm not worried about sending it off anything.

This is an interesting video that should alleviate any concerns

https://www.youtube.com/watch?v=xreZdUBqpJs

Very interesting, thanks for posting.

[anonymous-user]

Santa Cruz do carbon better/differently than most other brands I believe, don't expect every brand to stand up to that kind of abuse.

There's no rider weight limit on a Santa Cruz, they build them strong.

[Mr Gearchange]

Insert Coin said:

Santa Cruz do carbon better/differently than most other brands I believe, don't expect every brand to stand up to that kind of abuse.

There's no rider weight limit on a Santa Cruz, they build them strong.

I don't think that SC has any more or fewer warranty claims than anyone else -but their aftersales care is second to none.
They did have a problem with the early V10 carbons cracking around the bottom bracket - frames didn't fail but they did crack. This is why you can pick one up 2nd hand for very cheap compared to their £6-7K list price because the warranty doesn't transfer.

I'm sure all carbon frames are not made equally - I wouldn't want to ride Fort Bill on a cheap chinese carbon frame but anything from the mainstream big brands is going to have been built properly.
My YT carbon bike takes an astonishing amount of abuse - I regularly get through all of it's 200mm of suspension travel and the frame is still perfectly ok. I also crash it. A lot.

Edited by Mr Gearchange on Thursday 9th February 19:19

[gazza285]

Mr Gearchange said:

Don't know why people have these concerns - carbon fibre is a lot stronger than either aluminium or steel - which is why they use it...

A rather simplistic approach. Carbon fibre has a better strength to weight than alloy and steel, so manufacturers use it to make a lighter frame that is of equivalent strength, or else the extra expense would be for no gain. I'm sure a carbon frame that weighs the same as my On One Inbred beater would be nigh on indestructible, but to what end?

Carbon = lighter, but not necessarily stronger.

[Mr Gearchange]

gazza285 said:

Mr Gearchange said:

Don't know why people have these concerns - carbon fibre is a lot stronger than either aluminium or steel - which is why they use it...

A rather simplistic approach. Carbon fibre has a better strength to weight than alloy and steel, so manufacturers use it to make a lighter frame that is of equivalent strength, or else the extra expense would be for no gain. I'm sure a carbon frame that weighs the same as my On One Inbred beater would be nigh on indestructible, but to what end?

Carbon = lighter, but not necessarily stronger.

Slightly simplistic - but the video posted above suggests that the same frame in carbon is significantly stronger than the equivalent alloy one as well as being a lot lighter and stiffer to boot.