GT avalanche 1.0 2008

Rippedabs123

I have recently purchased a second hand GT avalanche 1.0 2008 and I am going to upgrade the bars to carbon riser, but the thing is I don't know what the stem clamp diameter is, any help?
Also can you please tell me what size the seat tube is so I can purchase a new seat collar as the one on the avalanche is rubbish?

The Rookie

Have a look at the exiating seatpost clamp, it will normally have marked inside the diameter, alternatively measure the circumference with a tape measure and divide by 3.14 to get the diameter, from memory though it's a 31.8mm

Bar clamp size will either be 25.4 or 31.8mm, easy enough to measure with a ruler!

chez_m356

Rippedabs123 wrote:

I have recently purchased a second hand GT avalanche 1.0 2008 and I am going to upgrade the bars to carbon riser, but the thing is I don't know what the stem clamp diameter is, any help?
Also can you please tell me what size the seat tube is so I can purchase a new seat collar as the one on the avalanche is rubbish?

bars are 31.8 spec here

http://www.evanscycles.com/products/gt/ ... 9#features

found this thread about the seat post

viewtopic.php?p=17245420 27.2 post and 31.8 clamp apparently ?

Rippedabs123

Awesome, thanks a million

Rippedabs123

I have also just been out in the garage with the bike and have realised that the crank arms have play in them and the headset is quite grindy, does this mean i will need to replace the bottom bracket? And what will I need to do about the headset?

The Rookie

Headset - if it's loose ball, strip clean, and reassemble with fresh grease often does the job.

BB- maybe, more likley the cranks are loose on the axle as even a fairly graunchy BB doesn't usually have much play - unless it's making a right racket

Rippedabs123

Right, so i dont need to get a new BB or headset?
All I need to do is clean the headset and tighten up the BB, easy!!

bartimaeus

And if you do need a new BB they can be had for £12.50 - Octalink ES25. I have a 2010 Avalanche - great bike.

Rippedabs123

Yes, i agree great bikes, and very light as well.
Thanks for the BB advice, you wouldnt happen to know what kind of headset would fit the bike and/or where to get one from.

The Rookie

Check parktools for headset standards or how about a photo.....almost certainly extrenal or semi-integrated (also called zero stack and fitting is internal), most likely the latter.

snoopsmydogg

Rippedabs123 wrote:

Yes, i agree great bikes, and very light as well.
Thanks for the BB advice, you wouldnt happen to know what kind of headset would fit the bike and/or where to get one from.

If its the same as my avalanche 3 from the same year then it's a semi integrated (zero stack) headset but mine is the loose ball type so it could just be a case of strip clean and regrease.

bartimaeus

Mine is a ZS - I did look up the spec but I forget - and it has caged-ball bearings, so if you are cleaning and regreasing then I would replace the bearings as they are only a couple of quid from your LBS.

Rippedabs123

It is a internal BB and I cleaned the headset today after riding croft trail in swindon thanks a loads for the advice guys.