5 mm make much difference in tyre width?

[Aushiker]

I managed to do a nice job of stuffing up an order on http://Bike24.net and now have a single Schwalbe Marathon Mondial 42-622 700Cx40 folding tyre when I initially planned to order two 47-622 700Cx45 folding tyres.

These are for my forthcoming Dreaming Tour which will involve a lot of dirt road/sandy/gravel riding (2,00 odd kilometres at least). So the question is do I:

(1) Sell the 42-622 700C x 40 and buy in two 47-622 700C x 45 tyres. That is will the extra 5 mm make that much difference?
(2) Keep the 42-622 and get a second one?
(3) Put the 42-622 700C x 40 on the Extrawheel Voyager and get two new 700C x 45 tyres (I was going to put an existing Marathon Cross on the trailer)?

They key question is will the 5 mm make that much difference?

Thanks
Andrew

 

[GrasB]

Not really, it's more about tyre construction & rubber than anything else. Unless you're going to be seriously pushing the loading envelope of the tyre I'd just use the thinner one for the front wheel.

 

[GrumpyGregry]

28mm -> 23mm yep

47mm -> 42mm rather less.

2.5" - > 2.2" (on an mtb) I can't tell the difference.

 

[HLaB]

In theory yes but on a fully loaded tourer that already had wide tires I doubt it'd be noticeable. But I can't see any harm in running different thickness tyres; my bikes have all had different thickness tyres at some point, my current town bike has 5mm different tyres (32mm front, 37mm rear).

 

[GrumpyGregry]

I always run wider on the front of the mtb than the rear. funny old world innit?

 

[Norm]

(1) Sell the 42-622 700C x 40 and buy in two 47-622 700C x 45 tyres. That is will the extra 5 mm make that much difference?
(2) Keep the 42-622 and get a second one?
(3) Put the 42-622 700C x 40 on the Extrawheel Voyager and get two new 700C x 45 tyres (I was going to put an existing Marathon Cross on the trailer)?

I think that you may have missed one (if you have bought them less than 7 days ago)...
(4) Return them under the Distance Selling regulations.

I wouldn't run 2 different sizes, but I'm not sure I could articulate why. If I was going to do it, I'd put the larger one on the front, as Greg says.

 

[HLaB]

I always run wider on the front of the mtb than the rear. funny old world innit?

Sheldon does a good piece on it, iirc on the back allows for more bum comfort but the wider tyre on the front allows for better control and more hand comfort.

Most bikes come with identical tires front and rear. This is all right for general use, but if you want to optimize your bike, you should consider using different tires front and rear. The front and rear tires have different loadings and different requirements.

• Narrower Front, Wider Rear
  
  If lightness is the primary goal, tire width/weight is limited by the risk of pinch cut flats, a.k.a. "snake bites." Since there is more weight carried on the rear tire, you can get away with a slightly narrower tire in front than you can in back.
• Wider Front, Narrower Rear
  
  A wider front tire makes sense in many applications, however, when handling and ride comfort are considered. A wider tire will generally provide better cornering traction than a narrower one, assuming appropriate inflation pressure.
  A wider tire also provides superior shock absorbency. I personally prefer a slightly wider tire in front, since I suffer from some wrist discomfort on occasion.

 

[willem]

On a rough trip I might want to have a spare. The 42 mm folding Mondial would do well for that. And yes I think 47 mm would be rather better for those off road miles. It would be meaningfully more comfortable, and give better grip.
Willem

 

[Aushiker]

Thanks for the responses. Some food for thought. A couple of comments:

With regards to the long distance selling regulations, the postage back to Germany from Australia pretty much kills that option in this instance but thanks for reminding me about them. Always handy to know.

I was planning to carry a spare but it was just going to be one of my existing Schwalbe Marathon Cross HS 3334 40-622 700 x 38 c but thinking about that, I wouldn't be keen on using one for any serious distance plus (1) getting to a bike shop on this ride could mean 1,000 + kilometres of riding and (2) 700C touring tyres are not going to be a stock item that is for sure.

So keeping the tyre I have as a spare is maybe the smart move. Now I have to give some more thought to the idea of mix of tyre widths . Something I hadn't consider before. The bike will be loaded up at times due to the need to carry 10 to 14 days of food and up to 30 litres of water. I will be using a Extrawheel Voyager trailer to help carry the load/distribute it out but still the bike will be loaded up.

Thanks very much for the input.

Andrew

 

[Norm]

With regards to the long distance selling regulations, the postage back to Germany from Australia pretty much kills that option in this instance but thanks for reminding me about them. Always handy to know.

Haa haa and Oh bugger!

Sorry about that, I was browsing on my phone and locations don't appear on that skin so I didn't realise where you were.

 

[willem]

So go for two 47 mm Mondial's on the bike (if you have the clearance) and take the folding 42 mm as a spare. I see no good reason to use two different sizes, unless you have to. If you have to, I think common wisdom is to use the wider/grippier at the front, for safer steering.
The tyre on the trailer will have a much lower load, so on the trailer you can probably use the Cross without ill effects (if it is still in good shape). I used to use a trailer, and the only serious wear was due to age.
Enjoy,
Willem