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Two Wheel Mayhem
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6 Posts
Discussion Starter · #1 ·
I have recently purchased a VT2 2004 with the 3 way swinger shock, and desperately want to change the seatpost to one without a shim.

My shock is upside down (shock shaft on top) so I think it will fit, and drop when I want it to.

I have a 30.9 specialized seatpost, but it fits really tightly (like it almost won't come out at all), so does everyone who has changed it use a 30.8?? Does 0.1mm really make a difference?

Does anyone use a layback post, as I find I am really close to the bars, and sitting back would help I think?

Apart from that I love the bike, and highly recommend 2.1 Fire XC pros!!!
 

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Niner EMD
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100 Posts
30.8 or 30.9. Are you using grease? It shouldnt be THAT tight if you are using a 30.9. Its snug but not too bad. Im running a 30.9 Thomson in my NRS.
 

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Reviewer/Tester
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6,176 Posts
I run a 30-9 in my VT-2 but it is quite a snug fit, and takes some effort to slide it up or down in the frame.

I would recommend the 30-8 for a better fit. It will be slightly easier to adjust, imo.



R.
 

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Registered
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10 Posts
I share your pain. Like you, I dumped the shim - went with a 30.8 post. the only one I could find was the Thompson Elite. It's a great post & fits well. However, no matter how far back I moved the seat, I still felt crowded on my 16.5 frame. After reading numerous reviews in this forum, and despite the fact that 0.1mm can make a major diference, I replaced the straight post with a Thompson Elite Set Back. Damn, if it doesn't fit like it was made for the bike. Were I you, I would definitely put the Thompson Set Back on your bike - you'll love the extra space & the better riding position.

If after replacing the post, you still feel cramped, try changing to a 10 degree stem instead of the stock 5 degree. I personally found it helped with cockpit space and overall handling.

Wish you the best with your new VT,

Dave
 

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IMBA Canada
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844 Posts
I have a VT2 and i'm getting fed up with all the noise that comes from the seat tower when dirt gets in the frame between the shim and post!!!!! IT's really annoying.

DON'T go for a layback seatpost, there most of the time useless. The position of your seat is critical. It aligns your body with the pedals. If you feel to short you might want to put a longer stem. Have you tried to flip down the stem just to see if you're bars are too high?
 

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Combat Wombat
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1,850 Posts
Eddie_fb said:
I have recently purchased a VT2 2004 with the 3 way swinger shock, and desperately want to change the seatpost to one without a shim.

My shock is upside down (shock shaft on top) so I think it will fit, and drop when I want it to.

I have a 30.9 specialized seatpost, but it fits really tightly (like it almost won't come out at all), so does everyone who has changed it use a 30.8?? Does 0.1mm really make a difference?

Does anyone use a layback post, as I find I am really close to the bars, and sitting back would help I think?

Apart from that I love the bike, and highly recommend 2.1 Fire XC pros!!!
I replaced the stock setup on my 2003 VT-1 with a Thomson 30.8 and it feels just right as far as how it fits into the frame.
Go with the setback. Considering that the Titec post that came with my VT has some setback, a straight Thomson post would actually move you more forward than the stock setup. The Thomson setback provides about 5/8" of setback. Where the Titec has the setback built into the head, the Thomson bends the post. Holding the Titec and a Thomson setback side by side, they are about identical as far as seat position goes.

Brian
 

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Rollin' a fatty
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5,863 Posts
Most of the aftermarket posts have somekind of seatback on the clamp area, Thomson is one of the few manufacturers that bend the tube for setback.

I run a 30.9 setback and a 110x5 stem and feels great on my 16.5 frame.
 

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IMBA Canada
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844 Posts
Getting a setback on a seatpost is USELESS! After that you need to put the seat all the way to the front to realign your ass with the pedals! Seat positionning is tricky, look it up on some road bike site, the same positionning applys to mountain bike.

When sitting on your bike, with pedals flat and parrallel to the ground, if you drop a straight and vertical line from the back of your knee cap, you should fall right onto the pedal axle! That's it. So if you put a setback on your seat post, to re-ajust to that position, you'll need to push the seat to the front anyways!
 

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Two Wheel Mayhem
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6 Posts
Discussion Starter · #12 ·
http://gallery.mtbr.com/showgallery.php?cat=500&ppuser=248674

The above link is to my gallery, and you can see in some of the pics, that I can lift the whole bike off the ground with an unsecured (QR completely loose) 30.9 seatpost. It cannot be designed to be that tight surely?

So I am now looking to fit a 30.8 seatpost, so do you have any recommendations? [and places to buy in the uk would be nice, and not ridiculous prices, cos I blew all I had on the bike!]

Cheers for all your advice,

Eddie.
 

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Niner EMD
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100 Posts
saddle setback is not a "uniform setup fits all applications" thing. In fact there is an amount it can be offset from the setup you described (kneecap to axle plumb line). Moving a seat rearward increases in the saddle power during climbs. Moving it forward helps keep the bike forward on climbs (if you have trouble with the front wheel lifting). And there is a lot to say about personal comfort and preference...which can vary greatly. As well as frame size being appropriate for the rider. Sometimes people choose a smaller frame which would require setback to be aligned.
That being said, you ARE correct about the ideal setup in terms of the knee cap lining up with the axle. This is the most balanced setup.
 

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Registered
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126 Posts
Eddie,
Did you shock come installed that way? That is upside down compared to my shock on my VT3 (20.5") I also have less seatpost coming out the bottom of my frame than you, I just am always suprised to hear so many people having clearance issues, but flipping the shock over seems to cancel that out.. Has anyone asked Manitou if that posses a problem with air/oil interaction?
 

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Rollin' a fatty
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5,863 Posts
Eddie, what you're experiencing is not right. You shouldn't lift the bike by the seat, probably the seat tower is too tight or the post is a bit bigger than it should.

I have a 30.9 Thomson on my VT and that doesn't happen to me, the post fits very snuggly but not as much as yours seems to be. Try to open a bit the seat tower, grease the post and give it a try to see how it goes; that was what I did with mine.
 

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Two Wheel Mayhem
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6 Posts
Discussion Starter · #16 ·
lamrith:

I believe the shock is the correct way up, as the manual and the main pic on the giant website has it inverted as well.
Also, with your observation that the seatpost/shock clearance on your bike is fine, well I think the different frame sizes seem to make this measurement differ by a fair amount.

Dirt Devil:

The post, and the inside of the frame was very well greased at the time of the photo! I am a bit reluctant to start levering the frame about, so I will just look at the 30.8 post options for now.

The reason I was a bit unhappy with the cockpit positioning was that it seemed a bit fast steering for me, would a longer stem (greater leverage) speed the steering?

Or would the longer stem mean I would have to move the bars further for the same steering effect (greater radius about fork steerer tube)?

Just wondering!

Thanks for all your advice,

Eddie.
 

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Combat Wombat
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1,850 Posts
I do not think a 30.9 would work for me either.

Eddie_fb said:
lamrith:

I believe the shock is the correct way up, as the manual and the main pic on the giant website has it inverted as well.
Also, with your observation that the seatpost/shock clearance on your bike is fine, well I think the different frame sizes seem to make this measurement differ by a fair amount.

Dirt Devil:

The post, and the inside of the frame was very well greased at the time of the photo! I am a bit reluctant to start levering the frame about, so I will just look at the 30.8 post options for now.

The reason I was a bit unhappy with the cockpit positioning was that it seemed a bit fast steering for me, would a longer stem (greater leverage) speed the steering?

Or would the longer stem mean I would have to move the bars further for the same steering effect (greater radius about fork steerer tube)?

Just wondering!

Thanks for all your advice,

Eddie.
I have a 30.8 Thomson on my VT-1 and it is pretty snug. Maybe the tolerances are enough from bike to bike to make a difference.

Brian
 

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www.justthebonnet.com
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1,475 Posts
I just put in (today) the thomson 30.9 straight seatpost. It is very tight but with grease it does slide. I think the thomson 30.8 is the way to go. But if you need a thomson setback, they make that in 30.9.
I bought the 30.9 by 367 and cut about two inches off of it.
 
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