Saddle set too far back on rails?

Monty1

Hi. I had a bike fit a while ago. To get by pedal position & stoke right, the saddle was set back as far as it will go on the seat rail. Way outside the markings on the rails. (I can't seem to post a photo). Is this likely to be a concern, or am I fretting about nothing?

mercia_man

Having saddle right back on rails outside the markings looks wrong and is potentially dangerous as it may put too much strain on the rails and cause them to break. You should consider a seatpost with more setback.

cooldad

Sounds like a rubbish fit, the markings are there for a reason.

To stop you getting a seat post up your arris when the rails snap.

svetty

Mercia Man wrote:

Having saddle right back on rails outside the markings looks wrong and is potentially dangerous as it may put too much strain on the rails and cause them to break. You should consider a seatpost with more setback.

^this. Assuming your current seatpost doesn't already have a decent amount of set-back and that your frame isn't actually far too small for you, you need to buy another seatpost.

joey54321

Depends on your weight, i'd say it'd likely be fine unless you are on the heavier side. There is quite a lot of safety built in to things like that. However, I would look for a seat post with more seatback if possible. It does seem odd the fitter didn't discuss it would you though.

Monty1

Thanks all for confirming my concerns. It was a compromise as I was told that the frame was a bit small.
Seatpost is 25.4 Cannondale. Not many options. Pondering a new bike in any event.

clickrumble

If the saddle is that far back, you may find you have problems with the front wheel lifting when pushing the pedals hard going up hill. I had this problem and solved it by fitting a longer stem, but this may not be possible in your case.

cougie

Makes sense if the frames too small for you.

How far have you ridden like that ? As has been said a lay by post will fix your position.

Monty1

Clickrumble wrote:

If the saddle is that far back, you may find you have problems with the front wheel lifting when pushing the pedals hard going up hill. I had this problem and solved it by fitting a longer stem, but this may not be possible in your case.

Not had that problem, to be honest.

Monty1

Thanks both.
Not had a problem on climbs, to be honest. Will ponder seat post etc.

svetty

Clickrumble wrote:

If the saddle is that far back, you may find you have problems with the front wheel lifting when pushing the pedals hard going up hill.

Maybe on Rosedale Chimney or Trooper Lane........

pilot_pete

Depending on the saddle, outside the markings may not be a straight part of the rails which isn’t designed to be clamped. And clamping on part of a curve could put undue pressure on a specific part of the rail which could lead to a failure.

To be honest, if the bike is too small and you can’t set the saddle any further back (if you already have a setback seatpost) and perhaps the bar drop is excessive requiring a number of spacers, you’ll neve4 be happy with it so I would just buy a correct sized frame/ bike and sell that one on before you wear everything out and it’s value reflects that.

PP

drlodge

Size of the frame has no relation to fore-aft position of the seat on post, as the seat tube angles are the same and this dictates the setback. It might be that the seat post angle is steep.

svetty

drlodge wrote:

Size of the frame has no relation to fore-aft position of the seat on post, as the seat tube angles are the same and this dictates the setback. It might be that the seat post angle is steep.

Depends on the frame - many frame designs have steeper seat tube angles to shorten the reach for smaller riders.

keezx

Unfortunately, a steeper seat angle only shortens the top tube, not the reach.

svetty

Keezx wrote:

Unfortunately, a steeper seat angle only shortens the top tube, not the reach.

Different uses of the word 'reach'.

You are using 'reach' as the label used to define the horizontal distance between the bottom bracket centre and the head-tube centre, my usage was to reference the distance the rider had to stretch forward to hold the bars. Neither wrong, just different

pilot_pete

Keezx wrote:

Unfortunately, a steeper seat angle only shortens the top tube, not the reach.

So, if the top tube is shorter and everything else remains the same, how is the reach not affected?

PP

drlodge

Pilot Pete wrote:

Keezx wrote:

Unfortunately, a steeper seat angle only shortens the top tube, not the reach.

So, if the top tube is shorter and everything else remains the same, how is the reach not affected?

PP

In this case, reach is defined as the distance between middle of bottom bracket and head tube centre (or something at the front). So actually, top tube can't be shorter and everything else remains the same, but if TT is shorter with length taken off the rear of it, then seat tube angle must be steeper, hence distance between bottom bracket and head tube remains the same.

pilot_pete

Ah I see, I thought he meant distance from saddle to bars...

ovi

doesn't bother Ty Magner

cougie

They've not thought out their decals and placement that we'll have they ?

Ben6899

I'd suggest Ty Magner's bike is too small for him - even allowing for the trend among Pros to size down a bit on the frame.

pblakeney

Monty1 wrote:

Thanks all for confirming my concerns. It was a compromise as I was told that the frame was a bit small.
Seatpost is 25.4 Cannondale. Not many options. Pondering a new bike in any event.

A temporary solution? Also, your new bike may not be set back that much further so a possible permanent solution. Just as an example.
http://www.wiggle.co.uk/thomson-elite-s ... 1252721822

Monty1

Thanks for the link and response.
Current seatpost is 25.4 mm 15 mm set back. Can't find a 25.4 with 25 mm set back thus far. Will keep looking.

Monty1

I have move the seat forward a bit on the rails.

pblakeney

Monty1 wrote:

Thanks for the link and response.
Current seatpost is 25.4 mm 15 mm set back. Can't find a 25.4 with 25 mm set back thus far. Will keep looking.

You sure it is 25.4mm OD?
That is an unusually small size.

dj58

PBlakeney wrote:

Monty1 wrote:

Thanks for the link and response.
Current seatpost is 25.4 mm 15 mm set back. Can't find a 25.4 with 25 mm set back thus far. Will keep looking.

You sure it is 25.4mm OD?
That is an unusually small size.

Not on a Dale.

Monty1

Yes, 25.4 - hence the problem.

pblakeney

Stupid Cannondale...

svetty

Monty1 wrote:

I have move the seat forward a bit on the rails.

Rather than ride a bike with a poor fit it sounds like you need to get another bike? A perfect excuse