Brooks rail length problem

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Brooks rail length problem

Postby Nobody » Sun Nov 20, 2011 5:42 pm

Rail length of original B17. ~14cm from front of rails to back of saddle. Good fit.
Image

Rail length of new Team Pro. ~13cm from front of rails to back of saddle. 1cm too far forward. Confirmed by other measurements on bike.
Image

As most of you already know, the usual problem with Brooks saddles is not being able to get the saddle back far enough due to short rails. I made the incorrect assumption that different saddles would have at least the same reference point to the rear of the saddle so you can just swap them, but I was obviously wrong. :roll:

Could someone with a Swift or Swallow please measure the front of the rail to back of saddle (like photos) and post it? I'm trying to figure out if I have any other Brooks options before looking elsewhere. I've already got a 30mm setback post and most frames of similar size to mine have a similar seat tube angles. Looks like I'm going to have to sell the Team Pro either way. :(

Thanks in advance.
Last edited by Nobody on Sun Nov 20, 2011 8:17 pm, edited 1 time in total.
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by BNA » Sun Nov 20, 2011 8:17 pm

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Re: Brooks rail length problem

Postby il padrone » Sun Nov 20, 2011 8:17 pm

Back end of the Swift to the front of the rail measures 140mm on mine.
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Re: Brooks rail length problem

Postby Nobody » Sun Nov 20, 2011 8:20 pm

Thanks Pete. Should have got the Swift then. Kicking myself now. :oops:

I think there is too little information on the Brooks site about measurements considering the limited amount of rail adjustment.
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Re: Brooks rail length problem

Postby bprb » Sun Nov 20, 2011 9:25 pm

I reckon my Swallow is closer to 15 cm. Hope that helps.

Edit: On second thought, I'll say 14 cm. Looking vertically at the desk it appeared 15 cm, but that wasn't perpendicular to the ruler (the rails aren't horizontal when the saddle is on the desk). When I look perpendicular to the ruler, I now think it's 14 cm.
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Re: Brooks rail length problem

Postby il padrone » Sun Nov 20, 2011 9:31 pm

Yep, the Swallow has notably longer rails. But at a notably higher price :(

[edit] Then again maybe not longer. It seems the Swallow just has a deceptively different bend in the front of the rail.

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Re: Brooks rail length problem

Postby Nobody » Sun Nov 20, 2011 10:46 pm

Thanks Bprb and Pete. :)

At least it looks like I have other options.

I'll give it one or two more shorter rides to see if I can get it to work, but I'd say it's very likely to be up for sale in a week or two if my knees complain.
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Re: Brooks rail length problem

Postby ray » Mon Nov 21, 2011 11:54 am

Nobody wrote:Thanks Bprb and Pete. :)

At least it looks like I have other options.

I'll give it one or two more shorter rides to see if I can get it to work, but I'd say it's very likely to be up for sale in a week or two if my knees complain.


There isn't too many options for seatposts with a setback greater than 30mm. If you still want to use the Brooks there are some 40mm+ setback options such as the Ambrosio Momentum Carbon (27.2 x 300/350 with 45mm setback) and the Nitto S-84 Steel (with 42mm setback - some quote 37mm). For me with small frame, short legs and steep seat tube angle need around 40mm setback.
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Re: Brooks rail length problem

Postby Nobody » Mon Nov 21, 2011 1:23 pm

ray wrote:There isn't too many options for seatposts with a setback greater than 30mm. If you still want to use the Brooks there are some 40mm+ setback options such as the Ambrosio Momentum Carbon (27.2 x 300/350 with 45mm setback) and the Nitto S-84 Steel (with 42mm setback - some quote 37mm). For me with small frame, short legs and steep seat tube angle need around 40mm setback.
Thanks Ray. :)

Very informative and good to know there are extra options. The problem is the Nitto S-84 is $119 which is more expensive than what I paid for the saddle. The Ambrosio is even more expensive. :shock: I suppose it is much cheaper than a custom frame though.

I worked out that with a 70cm saddle height (BB to saddle top) the difference between a 73 degree seat tube and and a 74.5 degree is 17.5mm. I also have 165mm cranks which also encourages me to want to go back 5mm further. So I'm trying to get at least 22.5mm further back than average.

I'll see how the ride goes today.
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Re: Brooks rail length problem

Postby Nobody » Mon Dec 12, 2011 7:35 pm

I bought the Nitto S-84 seatpost. Fitted it to find that the saddle setback with my configuration is exactly the same as the VO post. Why? Because the Nitto being a quality product has a long clamp and the VO has a short one (as viewed from the side). So the leading edge of each clamp is the same distance from the post centre. $135 for no fit result is disappointing. In hind sight, I should have sold the Pro and tried a Swallow or Swift. Oh well, at least I can warn people about it. The Nitto seatpost is a pretty item as retro bling. I don't know if I want to keep it yet so I've re-boxed it without using it to see if I want to sell it next year when people have money again. If I can't live with the position, I may sell the Pro too once I've broken it in a bit more. Oh well, another learning experience... :|

At least they look pretty together...
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Re: Brooks rail length problem

Postby Nobody » Mon Dec 12, 2011 10:02 pm

Interesting post from Tony Colegrave in the thread below. Looks like the Swallow (as suggested above) does have the ability to be set back 1cm more than other saddles.
http://www.bikeforums.net/archive/index ... 72667.html
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Re: Brooks rail length problem

Postby Nobody » Thu Feb 16, 2012 1:43 pm

I've decided to ditch the Surly CC in favor of another frame with a 73.5 degree STA instead of 74.5. This should give me about ~1.2cm more saddle setback at the top of the saddle (BB to saddle height 70cm).

For anyone else that may be looking for similar smaller frames with a slacker STA, look for steel touring bikes and old style steel road bikes. After looking around I found some examples:
http://www.fujibikes.com/bike/details/touring5
http://www.jamisbikes.com/canada/thebik ... elite.html
http://www.jamisbikes.com/canada/thebik ... rt_rd.html
http://www.somafab.com/archives/product ... n-frameset

I think I'm going to buy a Planet-X frame because it's cheap and has 73.5 degree STA for a 545mm ETT. The ETT will be shorter by 8.5mm due the difference in STA, so it will be like a 532.5mm ETT at 74.5 degrees.
http://www.on-one.co.uk/i/q/FRPXKV2/pla ... _out_frame
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Re: Brooks rail length problem

Postby Rich-Ti » Fri Feb 24, 2012 2:57 am

That's a lovely seatpost! Perfect match with the Brooks.
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Re: Brooks rail length problem

Postby MichaelB » Fri Feb 24, 2012 8:52 am

So, that's a bugger, especially since it's such a nice seatpost.

Good way to get a new frame "But the seat doesn't go back far enough dear ......"

So, the options for me are a New Brooks Swallow (AT) $159 for the Chriome rail version or $300 for the Ti version (ooooohhhhh the WW in me is seeing value in 200g less ..... :roll: ) or try and find a new seatpost with more setback.

But the important Q is - how different is the profile of the Swallow compared to the Team Pro ?

Anyone with experience using the Swallow & Team Pro ?
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Re: Brooks rail length problem

Postby Mulger bill » Fri Feb 24, 2012 7:29 pm

Swallow Ti is a lovely bit of kit Michael.
I haven't used a Pro so it's grain of salt time but going on googled pics of one, the Swallow is almost dead flat along the top, effectively zero sag on mine, even after I dunno how many kms (bum bone dimples aside). I haven't touched the tension. It looks from above to be narrower through the mid section too, the folded and riveted flaps stop it splaying out. I can't find a decent pic of Pro rails from the underside to make an honest comparison but the Swallow doesn't give a huge amount of room either.

Hope there's some nugget of assistance in all this waffle. :)

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Re: Brooks rail length problem

Postby MichaelB » Sat Feb 25, 2012 3:37 pm

Cheers MB, I think though that if i go down that path, a seatpost with more setback might be the better (& cheaper) option.

Ooorooo
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Re: Brooks rail length problem

Postby Nobody » Sat Jan 11, 2014 6:34 am

Thanks to all who offered advice on this thread.

As a conclusion to this thread, I ended up replacing the Pro with a WTB Speed V Comp. It had the advantages of ample rail length and better comfort for me in a road bike position. It's significantly cheaper too.

Another frame that people might want to consider if they can't drag themselves away from a saddle with short rails is the Planet X Kaffenback 2. It has a 72.5 degree STA which is rare in a modern small sized frame.
http://www.planetx.co.uk/i/q/FRPXKBD2/p ... e-and-fork
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Re: Brooks rail length problem

Postby warthog1 » Sat Jan 11, 2014 7:23 am

I'm no expert on knees or bike fit as you know, but I'm wondering if you can explain to me why you are so far back behind the bottom bracket. The current racing practice seems to be run a long stem on a smaller frame, for its shorter head tube, and have the seat as far forward as is legal or you can get away with.
Having the seat a long way behind the bb and attempting to ride in the drops would close up the hip angle a fair bit :?
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Re: Brooks rail length problem

Postby Nobody » Sat Jan 11, 2014 12:01 pm

warthog1 wrote:I'm no expert on knees or bike fit as you know, but I'm wondering if you can explain to me why you are so far back behind the bottom bracket. The current racing practice seems to be run a long stem on a smaller frame, for its shorter head tube, and have the seat as far forward as is legal or you can get away with.
Having the seat a long way behind the bb and attempting to ride in the drops would close up the hip angle a fair bit :?
Currently 5mm behind KOPS. It's not that I'm so far back, but it's the the STA is so steep and I have 165 cranks. So to be 5mm behind KOPS is actually 10mm behind the norm 170mm crank position due to 5mm shorter crank length. Then a 74.5 deg STA puts the seatpost at the saddle about 12mm more forward than a 73 deg STA. So to be 5mm behind KOPS puts the saddle a total of 22mm behind a "normal" position on a seatpost. This might be OK with a modern saddle - although a setback VO seatpost still helps to place it in the middle of the saddle rails - but not good for a short railed Brooks Pro.

I found it interesting to read in "Greg LeMond's Complete Book of Bicycling" from 1988 in which he said to hang the plumb line off the front of the knee (not the position we measure from now) and it should "bisect exactly the center of the pedal axle or fall as much as one or two centimeters behind." But the different measuring style for "bisect exactly the center of the pedal axle" is actually 5mm behind KOPS using the current measuring method.
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Re: Brooks rail length problem

Postby warthog1 » Sat Jan 11, 2014 1:51 pm

Thanks, more upright seat tube and shorter tube means the seat is further forward and combined with those silly little cranks :P , you need it to be further back? Just repeating it back to make sure I got it correct. :oops: :)
Do you get sore knees if you run the seat further forward?
I've never actually looked at the KOPS situation on my bikes. As you say with longer cranks I may need to be further forward anyway.
Looking at people who are in the drops and going hard I've noticed many pull themselves forward "on the rivet" to try and generate power I guess.
I found the tt bike was faster in a forward position due to the more open hip angle so replicated that on the roadie a bit.
Maybe you can try a longer stem, move forward a bit if the knees allow and still use the brooks if it works?
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Re: Brooks rail length problem

Postby Nobody » Sat Jan 11, 2014 5:43 pm

warthog1 wrote:Thanks, more upright seat tube and shorter tube means the seat is further forward and combined with those silly little cranks :P , you need it to be further back?
Summary:
<<10mm saddle (fit & cranks)
seatpost 12mm>> (STA)

warthog1 wrote:Do you get sore knees if you run the seat further forward?
In theory I should and so I don't usually try it. I don't get sore knees much while riding, mainly the next day after a ride. But I've done the following now and my knees are better than they have been since I restarted cycling in 2008:
Shimano road pedals/shoes with cleats back and out
G8 Performance custom fit insoles.
Steve Hogg heel wedges.
Bikefit cleat wedges.
3mm custom cleat shim.
Saddle down 4mm, back 5mm.
Using foam roller on ITB & leg muscles after rides.
Lost 10Kg with a change of diet.

I'm also considering getting a single chainwheel setup to reduce my Q-Factor/Step from 147 to 134mm which also should help. In the end it's about accumulative small gains. This fit thing is expensive. I think the crank setup will probably cost about $300 landed and may make no difference at all. But still worth trying.

warthog1 wrote:I've never actually looked at the KOPS situation on my bikes. As you say with longer cranks I may need to be further forward anyway.
Looking at people who are in the drops and going hard I've noticed many pull themselves forward "on the rivet" to try and generate power I guess.
I found the tt bike was faster in a forward position due to the more open hip angle so replicated that on the roadie a bit.
Maybe you can try a longer stem, move forward a bit if the knees allow and still use the brooks if it works?
If I get everything else sorted to reduce my knee pain to next to nothing (priority 1 recently) I may try that setup to see the impact on my knees. No point trying it until the knee pain is gone long term, as I could be adding to the problem. I found changing the fuel for the engine is making more difference than any fit or equipment change. :)

According to LeMond, moving the saddle back uses the muscles behind the leg more. Therefore I can see an advantage of having the saddle back so I'm working different muscles when standing to sitting. Since the hills in my area are fairly short, I like to attack them standing these days. Probably no advantage doing a TT, but since I'm not doing TTs...
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Re: Brooks rail length problem

Postby warthog1 » Sat Jan 11, 2014 8:02 pm

Nobody wrote: I don't get sore knees much while riding, mainly the next day after a ride. But I've done the following now and my knees are better than they have been since I restarted cycling in 2008:
Shimano road pedals/shoes with cleats back and out
G8 Performance custom fit insoles.
Steve Hogg heel wedges.
Bikefit cleat wedges.
3mm custom cleat shim.
Saddle down 4mm, back 5mm.
Using foam roller on ITB & leg muscles after rides.
Lost 10Kg with a change of diet.

I'm also considering getting a single chainwheel setup to reduce my Q-Factor/Step from 147 to 134mm which also should help. In the end it's about accumulative small gains. This fit thing is expensive. I think the crank setup will probably cost about $300 landed and may make no difference at all. But still worth trying.


Well thats a bit more thought out than my random trial and error changes. Sounds like you are all over it :o
I'll shut up now :lol:
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