How critical are the limit guides on saddle rails?

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freiston
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Location: Coventry

How critical are the limit guides on saddle rails?

Post by freiston »

I've been given a Selle Italia Epoca leather saddle and today I set about swapping out the Passport Navigator saddle that I currently have on my bike (I get on with the Navigator but would like to give the Epoca a go and see if I find it as amazing as the donor has found his).

I realise that it is a very different saddle to the Navigator and that the setup is likely to be different to achieve best fit. I have a spare seatpost and so decided to fix the saddle to that and swap out the seatpost and saddle together as a "single unit" (then if I do decide to swap back, the Navigator only needs to be set to the correct height with no adjustment of setback and tilt).

I also have a Carradice Bagman QR bracket in regular use that I really want to keep using. The Epoca has saddlebag loops but I want the QR feature that the Bagman provides.

I have my Navigator set back on the rails to the limit marker and so I also fixed the Epoca to the seatpost at the limit marker but noticed that this places the saddle (to my eye) slightly further forward than the Navigator on its seatpost (different brand/model).

When I went to fix the Bagman QR bracket to the saddle rails, there isn't enough straight exposed rail behind the saddle clamp to fix it - I reckon I need about another 4mm before the bend in the rails.

What are opinions on whether it would be acceptable/safe/problematic to clamp the saddle about 4mm beyond the limit marker? For illustration, here are some pictures.
IMG_5448.JPG
IMG_5449.JPG
IMG_5450.JPG
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)
Jdsk
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Re: How critical are the limit guides on saddle rails?

Post by Jdsk »

I'd be prepared to do on it my own bike for me to ride.

What's your body mass compared to the population of intended users? If it's low that will reduce the risk, and that might provide some reassurance.

Jonathan
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freiston
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Re: How critical are the limit guides on saddle rails?

Post by freiston »

Jdsk wrote: 27 Jan 2022, 11:15am I'd be prepared to do on it my own bike for me to ride.

What's your body mass compared to the population of intended users? If it's low that will reduce the risk, and that might provide some reassurance.

Jonathan
Thanks for the reply.
There's a point! It varies a lot but my intention is for it to go down. Currently at 78.5 kg (approx. 12st 5lbs) but last October was 75 kg (11st 11lbs) and in May last year it was 83.5 kg (13st 2lbs) - I keep a spreadsheet :lol:

My saddlebag adds another 3 kg to that (and is attached to the rails on the end of a 6cm bracket)
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)
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freiston
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Location: Coventry

Re: How critical are the limit guides on saddle rails?

Post by freiston »

I've decided to give it a go.
A quick sit on the bike after fitting the saddle feels pretty much same as the old saddle in terms of position, but a lot firmer and a bit wider. I'm expecting that as the saddle breaks in, it will soften a bit and mould to the sit bones in such a way that makes the width requirement different to that of a non-leather plastic based saddle.

EDIT: The bag sits a bit lower and now rests on my rear rack

Here is the limit marker buried in the front end of the clamp.
IMG_5455.JPG
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)
Norman H
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Joined: 31 Jul 2011, 4:39pm

Re: How critical are the limit guides on saddle rails?

Post by Norman H »

I don't think you will have any problem there.

Many saddles don't have defined limits, you just have to ensure that the clamp sits somewhere between the straight parallel sections of the rails. Clamping where the rails begin to curve is definitely not a good idea, but often a few extra millimetres can be gained by locally relieving the clamp, by careful use of a file. The other consideration, especially if you're a little overweight, is to ensure that you don't have too much weight cantilevered beyond the clamp.
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Paulatic
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Re: How critical are the limit guides on saddle rails?

Post by Paulatic »

I’ve ignored limit markers for 30 years with no consequences.
Whatever I am, wherever I am, this is me. This is my life

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freiston
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Re: How critical are the limit guides on saddle rails?

Post by freiston »

I went for a short ride with it today. I did forget to treat the leather with the supplied cream before going out but I don't suppose that'll make a significant difference. Despite me ensuring it was the correct height, I needed to stop and raise it by about 4 or 5 mm (not a lot but it made a big difference). I suppose that the leather gives a bit under duress and effectively reduces the "sitting" height. I did find that I was sliding forward a bit and having to counteract that with pedal pressure (which in turn made my knees complain a bit more than usual). I don't think there's scope for tilting the saddle back on account of pressure on the perineum but I'm hoping that as it breaks in, it will cradle me more and cause me to slide forward less. The saddle did feel a bit too firm and hard but only marginally - again, this is something that I anticipate improving with breaking-in time. My usual rides are quite up and down circuits (about 80 feet per mile according to Google Earth) and I'm in the habit of pedalling about half the distance, free-wheeling half.

My rides are usually on the shorter end of the spectrum and my old saddle was quite comfy certainly up to my usual distances of not more than about 35 miles though with the old saddle I did get quite a bit of that "scrunched up" discomfort where I had to occasionally lift my backside off the saddle and pull (peel?) my underwear/shorts/tights away from my skin. I've never discussed this with other cyclists so I don't know if this is a familiar scenario for other gentlemen cyclists (the scrunching up I'm referring to wouldn't affect women). I never had any of that with the leather saddle.

So all in all, after one relatively short ride (only 17 miles this time - but I'm slow so that's over 1½ hours in the saddle), I'm impressed and optimistic; I'm going to keep it on the bike unless something bad develops. I dare say that I will have to tweak the height and position as the saddle breaks in but that's par for the course.
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)
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