djpfine

My seat is moved as far back as it will go on my small Giant Defy. The bike feels great on the road and I can ride 40-60 miles in comfort. However, I'm starting to feel like I should be sitting just a tad further back to align my knees over the pedal more. Two questions:

1. Is there any way for me to adjust the seat further back on my current frame? Can I buy a seatpost that is set back even further? Can I actually still move this current seat further back onto the part where the silver bars "bend"?

2. How do I know I'm not just thinking of problems where there are none? Is there a way for me to figure out what my optimal position should be on my own? I'd like to pay for a fitting but don't have the budget for it right now.

Quel

Can't move that seat back any more, no space. A general position to shoot for (though not everyone would agree) is KOPS...knee over pedal spindle. Ultimately, you go with whats comfortable and powerful and won't leave you with any injuries.

Normally I'd say get a setback seatpost to try to go back further, but looks like thats an integrated seat mast, so it's tough to say what to do. Not sure if Giant sells a different seat mast that would give you a bit more seat setback.

xdrmusclex

Thomson Setback seatpost...that is all

xdrmusclex

That does not look integrated. Giant Defy does not have an integrated seatmast, just a post with giant logos on it.

djpfine

Should I have tried to fit myself on a medium frame instead since I'm pushing this one to the limit?

Quel

Ah, k, didn't even pay attention enough to realize it was a Defy. Just looked integrated based on the pic. My bad.

LesterOfPuppets

yes

yes, go with the seatpost drmuscle mentioned or one of the many other setback posts.

You can, but you don't want to.

if your hamstrings hurt or you suck at climbing or your hands hurt or you're unintentionally popping wheelies all the time can indicate a saddle whose fore/aft is outta wack.

KOPS will ballpark it for ya.

queerpunk

Thomsons with setback have about 10mm of setback. Most seatposts with any setback have 20-25mm.

urbanknight

Yep, as much as I love Thomson, the OP should try a 25mm setback seatpost.

M_FactorX19

We have the opposite problem I need a post with less or zero setback on one of my bikes. I'm at the limit but would like to sit in the middle of the rails and be just a tad further forward.

scirocco

As far as the saddle issue goes? No. The small and medium Defy have the same 73 degree seattube angle. If you had an M frame the seatpost would be slid down a little in the seattube to compensate for the longer length. But the saddle on top of it all would have been in the same place.

You may have other reasons to want an M rather than a S but changing won't fix the saddle issues you have.

cooleric1234

fsa makes a seatpost with like 32 mm of setback, if it should come to that.

LesterOfPuppets

And then there's the 2.5" of setback on this beauty.

AEO

garbage.
If you need lots of setback, thomson, setback or not, is garbage.

For quality aluminum seatposts with setback, it's either Velo Orange grand cru 32mm or kalloy uno 30mm

another option is to use a saddle with more rail, like what specialized offers on their alias, toupe and other similar higher end BG saddles. Butt, seatposts are cheaper and it's not a guarantee that the saddle will be liked by the ass.

gsteinb

an aluminum post on a carbon bike?

gsteinb

Your position is likely off some (most are) but more often than not people create problems where there are none. Before you start with fittings or arbitrarily adjusting your position at least start by posting some photos of yourself on the bike to give a look at where you are. Tops; drops; leg fully extended; cranks horizontal. It's a BF right of passage any way.

xdrmusclex

Sacrilege! I found that when I changed over to a Thomson post (my brooks team pro does not have all that much space to move fore and aft), by ride changed quite dramatically. Brooks can be had for around $50 on ebay and CL (or if you have a hookup at a shop they are only $55 at cost)

cooleric1234

Thomson may make a great seatpost, but the point is that their setback model only has 16 mm of setback. Most regular seatposts have 20 mm. That's not the post to use if you need above average setback.

DXchulo

I've never heard anyone call a Thomson seatpost garbage. Maybe they don't make them with as much setback as you'd like, but does that make them garbage?

xdrmusclex

not enough setback for you ≠ garbage

cooleric1234

I'm not the one who originally said that, but I think he has a point. These were his words:

Notice he didn't say they are just garbage altogether, he said they are garbage if you need a lot of setback. I tend to agree that no matter how well made or light the seatpost is if it doesn't allow you to be fit correctly it's not even worth considering.

xdrmusclex

ok, now we are just arguing minutia and the incorrect usage of commas. Im guessing the original "garbage" person meant: "if you need lots of setback, a Thomson setback is not for you."

Probably the advise should read: "if you need alot of setback, the frame is not right for you."

DaveSSS 

The seatpost show has a significant setback. The listed setbacks are measured from the center of the post to the center of the clamp. The post shown has more setback than any Thomson. If the OP wants more, something like and FSA with 32mm of setback might do the trick.

AEO

correct.

what's wrong with my use of commas and punctuation?
I just made it more fragmented, but the point is clear.

And no, proper road frames are made with 72 to 74 degree STA and HTA. If you need more setback on a standard frame, then it's more of an issue with body proportions.

pacificaslim

Huh? What change in frame would you suggest to better fit people with long legs? Some sort of extreme seat post angle (which of course is going to require stretching out the wheelbase so the wheel doesn't hit the seat tube)? It makes much more sense to use a typical 73 degree frame and make an adjustment by using a setback seatpost.