[Ted_R]

Hi Guys,


I bought a Trek/Gary Fisher Cobia last weekend and it comes stock with a 2.0 width tire in back and a 2.25 in front. I imagine their is a good reason for that but I am curious as to what that reason is.

The 2.25 looks macho and beefy compared to the 2.0 which looks kinda wimpy. Its tempting to put a 2.25 in back also. Is there a good reason not to do this ?


Thanks,

Ted

 

[YellaLab]

Hi Guys,

I bought a Trek/Gary Fisher Cobia last weekend and it comes stock with a 2.0 width tire in back and a 2.25 in front. I imagine their is a good reason for that but I am curious as to what that reason is.

The 2.25 looks macho and beefy compared to the 2.0 which looks kinda wimpy. Its tempting to put a 2.25 in back also. Is there a good reason not to do this ?

Thanks,

Ted

Just a guess but perhaps tire clearance? I have a 2009 Paragon with a 2.4 MK on the back and it barely clears. In the mud it cakes back on the tire but still a kick ass bike. Is there a lot of clearance in the 2011 model?

 

[Tinshield]

Most of the time this is done for weight and/or clearance. Because the back tire doesn't need as much side bite as the front you can get away with a narrower profile.

 

[qa_bugfinder]

I have a 2011 Paragon that came with a 2.25 in front and a 2.20 in back. However a the Superfly 100 has a similar setup as yours with a 2.25 iin fron and a 2.0 in back. The bigger front tire is for improved traction and smaller back is for less rolling resistance. You can get by with less traction in back because its easier to control a rear spin versus a front tire sliding out. It comes down to personal preferences.

I run a 2.2 Kenda Karma in front and a 2.1 SB8 in the rear on my 26" FS Trek. If its at all wet the SB8 packs up quick and isn't good, but when its dry it rolls very well.

A 2.2 or 2.25 should fit fine its not a clearance issue. A 2.4 might be close depending on if you have your chain stay wrapped to protect it.

 

[Ted_R]

Thanks Guys,


From lookin at the bike, it looks like clearance would not be a problem with a 2.25 on the back, just like bugfinder said. Also If I remember correctly the Paragon has essentially the same frame as the Cobia.

So maybe I can get beefy after all

I reckon it wouldn't hurt to fire off a message to Trek either.

Appreciate everyones help

Ted

 

[DavidR1]

I think a smaller tire in the rear is pretty common. You just don't need a huge rear tire.

 

[willtsmith_nwi]

Anti-Mullet

 

[Samwise the Brave]

Fatter tires in front help you track and corner better usually. I have a GF paragon and put a 2.4 in front, 2.1 in back.

 

[cbchess]

That is my preferred set up. I run a 2.2 or 2.4 up front for extra grip and extra cushy, then something small and fast out back for better acceleration and much quicker rolling. I usually run an ADvantage or Ardent up front and a crossmark 2.1 out back. This makes for a great tire combo. If I put big tire in the back is slows me WAY down and I feel like I am dragging an anchor around.

 

[Samwise the Brave]

That is my preferred set up. I run a 2.2 or 2.4 up front for extra grip and extra cushy, then something small and fast out back for better acceleration and much quicker rolling. I usually run an ADvantage or Ardent up front and a crossmark 2.1 out back. This makes for a great tire combo. If I put big tire in the back is slows me WAY down and I feel like I am dragging an anchor around.

Yeah, Ardent up front for me too. And Ignitor in the back

 

[ozynigma]

I reckon it wouldn't hurt to fire off a message to Trek either.

To congratulate them I hope.

A lot of riders change the stock rubber to get just the kind of setup Trek have given you out of the box.

 

[Ted_R]

To congratulate them I hope.

A lot of riders change the stock rubber to get just the kind of setup Trek have given you out of the box.

If my post sounds like I have a complaint I certainly don't mean it that way, I would just be asking about them about the benefits of the current setup as compared to a fatter tire in the back. Sounds like most folks are agreed that the current configuration has benefits and is popular. If running a fatter tire in back would slow me way down then that doesn't sound to appealing. I am sure Trek had a good reason for doing things this way. Asking them what that reason is would help to increase my understanding of mountain bike theory and design, which is the main reason I posted this question here in the forum. My experience with Trek products so far has been excellent and this bike is no exception.

Lots of helpful responses here, thanks everyone

Ted

 

[CB2]

Your front and rear tires have different jobs.
In most situations your front is for steering and control, whereas your rear is for driving you forward.