Avalanche v's Carrera Kraken average speed

Joeyblackball
Joeyblackball Posts: 5
edited May 2009 in MTB general
Got my son a new GT Avalanche but he struggles to ride to the speed he can acheive on my old Kraken. Been out today done our usual 12 mile training loop and he averages at best 9 MPH, he has been using my old Kraken for the last week cos he had a flat tyre and he easily does 14 MPH and even on the weekend 30 miler he done 12 MPH.

Anybody got an explanation, the Kraken components are bearly working, the forks squeek like mad and the brakes are non existent. Thought it might have someting to do with the Crank.

It could be an Ebay jobby and fixing up the Kraken if he doesn't get any better, we are doing the W2W at the end of June.

Comments

  • supersonic
    supersonic Posts: 82,708
    Could be he just needs to get used to the bike, the gearing - maybe it weighs more, different weight distribution. How about tyres?
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  • toasty
    toasty Posts: 2,598
    My Avalanche came with Stick-E Nevegal tyres, wire beads ones too that weighed just shy of 1kg each. It was much faster with some speedy, harder XC tyres on.
    Stumpy FSR 29er
  • Northwind
    Northwind Posts: 14,675
    Tyres would be my suspicion too... The current Kraken comes with horrible Tioga Factory XCs but maybe yours has something different? The stick-e nevegals aren't fast.
    Uncompromising extremist
  • rudedog
    rudedog Posts: 523
    sorry if its something you've already checked but do the wheels spin freely? When I got my bike from Halfords, some mong had really overtightened the quick release clamps on the wheels meaning there was way too much resistance on them.
  • Andy
    Andy Posts: 8,207
    rudedog wrote:
    sorry if its something you've already checked but do the wheels spin freely? When I got my bike from Halfords, some mong had really overtightened the quick release clamps on the wheels meaning there was way too much resistance on them.

    Overtightening the QR's will have no bearing on how freely the wheels spin. Its almost certainly down to something like the wheels not being in straight to begin with instead.
  • myopic
    myopic Posts: 692
    Assuming your are talking about average speed and not fastest achieved speed, maybe the answer is in your comment about the brakes being non existent on what is currently the "faster" bike? If he's used to braking early and firmly to make anything happen on the old bike, then riding in the same style on his new bike with effective brakes means he'll be losing more speed earlier and then having to spend more time working to build it up again.
    You don't need eyes to see, you need vision
  • Joeyblackball
    Joeyblackball Posts: 5
    Thanks for the relpies everyone.

    I have rode the GT and did not find it a problem, it was after he first road the carerra I couldn't keep up with him, he is 14 and I thought he had cracked the fitness, but it seems like a big step back after last nights loop.

    In answer to the questions:

    The tyres are still the Toga's
    The QR's seam fine
    Tyre pressure Ok too
    And it was average speed

    I even put a speedometer on as I thought it may have been the speed that pushed him along on the Kraken.

    Now thinking it could be the geometry, looks like I will spending some cash on the Kraken for our ride.
  • Ridg
    Ridg Posts: 98
    I've got an older 2004 avalanche and my friend has a 2007, I constantly find that mine runs quicker than his, but as the frames are pretty much identical, and we weigh about the same, we think its down to his hubs and tyres.

    so you might want to check that the hub bearings aren't too tight, as that will really reduce the speed.

    also worth checking that nothing is rubbing eg pads catching on the disc rotor / rim
  • Northwind
    Northwind Posts: 14,675
    rudedog wrote:
    sorry if its something you've already checked but do the wheels spin freely? When I got my bike from Halfords, some mong had really overtightened the quick release clamps on the wheels meaning there was way too much resistance on them.

    As Andrew156 pointed out, nothing you can do to the QRs will affect how the wheels spin.
    Uncompromising extremist
  • Ridg
    Ridg Posts: 98
    Northwind wrote:
    rudedog wrote:
    sorry if its something you've already checked but do the wheels spin freely? When I got my bike from Halfords, some mong had really overtightened the quick release clamps on the wheels meaning there was way too much resistance on them.

    As Andrew156 pointed out, nothing you can do to the QRs will affect how the wheels spin.

    i wasn't talking about the QR but the actually hub bearings as in the cone that sits on the axle, if those have been done up too tightly then the wheel wont spin on the axel
  • Northwind
    Northwind Posts: 14,675
    Fair enough then, it's just that you said it was the quick releases ;) But yep, very easy to overighten those if you don't know what you're doing.
    Uncompromising extremist

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