Berk PROTO-TYPE Composites

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sychen
Posts: 352
Joined: Thu Apr 24, 2014 1:06 pm

by sychen

Been getting some saddle slippage..
Also results in clamp tilt changes. Specialised Tarmac sl6 have one bolt seat clamps. If the saddle isn't tight then saddle and tilt shifts. This happens at 5nm without paste.

Caliper shows the Specialised power have a 7.39mm real width and lupina a very correct 6.99mm.

Would it be an issue with wrapping the rails with some electrical/duct tape , would it add some stress risers to rail if tape is slightly uneven?

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jhalmar
Posts: 41
Joined: Sat Aug 24, 2013 5:11 am

by jhalmar

sychen wrote:Been getting some saddle slippage..
Also results in clamp tilt changes. Specialised Tarmac sl6 have one bolt seat clamps. If the saddle isn't tight then saddle and tilt shifts. This happens at 5nm without paste.
Tarmac SL6 seat clamp torque is 13.5Nm.

by Weenie


sychen
Posts: 352
Joined: Thu Apr 24, 2014 1:06 pm

by sychen

jhalmar wrote:
sychen wrote:Been getting some saddle slippage..
Also results in clamp tilt changes. Specialised Tarmac sl6 have one bolt seat clamps. If the saddle isn't tight then saddle and tilt shifts. This happens at 5nm without paste.
Tarmac SL6 seat clamp torque is 13.5Nm.
Pretty sure the Berk recommended limit for the saddle rail is only 5nm.

With only a single bolt.. Have to go with the lowest number...no?

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jhalmar
Posts: 41
Joined: Sat Aug 24, 2013 5:11 am

by jhalmar

You are correct that Berks max torque is 5Nm. But Specialized saddle clamp holds the saddle rail without ”sharp” torque from pretty long area so I would at least ask from Berk that is it ok to use more torque on this kind of clamping system.

I have now S-Works Romin Evo saddle and I am also thinking to try Berk Lupina so if you get the answer it would be useful to share it here also

NiFTY
Posts: 1222
Joined: Sat May 26, 2012 11:26 pm

by NiFTY

For side clamp you can use more. I asked berk when i got mine as i had a one bolt superlogic. Tightened to 11nm. Nil issues.
Evo 4.9kg SL3 6.64kg Slice RS 8.89kg viewtopic.php?f=10&t=110579" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

sychen
Posts: 352
Joined: Thu Apr 24, 2014 1:06 pm

by sychen

Thanks guys, Reached out to our favorite carbon cowboy on PM and pending his response.. will post here when I get it.

HarrisonK
Posts: 48
Joined: Sun May 27, 2018 8:20 pm
Location: Main Line, PA

by HarrisonK

Installed my Lupina saddle yesterday and took it for a test ride this morning. I love it so far! I had a fizik arione versus evo first and had considerable numbing within 5 minutes on the bike. I thought it was from the cold winds and lack of insulation in the shorts. After riding this saddle for 50 minutes this morning, I can happily say that I didn't have any numbness or uncomfort at all during my ride. The saddle looks and feels great. My only concern is that, at only 70 grams, it might be fragile. I wish the prices would come down $100USD so I could buy another.

Image

RyanH
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Location: Los Angeles, CA
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by RyanH

@sychen it's already been covered in this thread somewhere. You can safely increase the torque since the recommended torque specs are for yoke type seatposts.

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Kimmoth
Posts: 43
Joined: Wed May 30, 2018 11:33 am
Location: Melbourne, Oz
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by Kimmoth

HarrisonK wrote:
Thu Jun 21, 2018 3:39 pm
Image
Hey, the little brace across the back is totally not square...

Delorre
Posts: 966
Joined: Sat May 24, 2014 12:09 pm

by Delorre

RyanH wrote:
Mon Jun 25, 2018 12:54 am
@sychen it's already been covered in this thread somewhere. You can safely increase the torque since the recommended torque specs are for yoke type seatposts.
Be carefull, at 6nm with a 2 bolt Ritchey seatpost, I got an indent on one of the rails and a light 'crack' sound. Didn't go any further and didn't have any issues with the rail once fitted, but be warned 😉 With my last one, I kept it to 5nm. With my sworks saddles, I went to 10 or 12nm without any issues using the same seatpost, so I suspect the Berk rails, even the oval ones rated to 100kg riders, to be a lot less robust than heavier saddles. But you have to save on somthing to reach 70gr 😯

Delorre
Posts: 966
Joined: Sat May 24, 2014 12:09 pm

by Delorre

HarrisonK wrote:
Mon Jun 25, 2018 12:29 am
My only concern is that, at only 70 grams, it might be fragile.
Yours is a 3K one, should be trouble free, as opposed to the UD ones (I cracked 2, Jure confirmed there are issues with those) My replacement is a covered 3K one, and until now, no issues👍

NiFTY
Posts: 1222
Joined: Sat May 26, 2012 11:26 pm

by NiFTY

I thought the UD was a cosmetic layer over a normal 3k construction, which is why it weighed more.
Evo 4.9kg SL3 6.64kg Slice RS 8.89kg viewtopic.php?f=10&t=110579" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

JackRussellRacing
Posts: 239
Joined: Thu Nov 03, 2016 4:32 pm
Location: North Carolina, USA

by JackRussellRacing

Delorre wrote:
Mon Jun 25, 2018 1:50 pm
Yours is a 3K one, should be trouble free, as opposed to the UD ones (I cracked 2, Jure confirmed there are issues with those) My replacement is a covered 3K one, and until now, no issues👍

I have probably 15k miles between two Berk 3K Plain Matte saddles, in a variety of horrible/good/great riding conditions, over the last 18 months. Zero issues whatsoever. Both are on Pinarello GAN RS bikes. I'm ~ 63kg, FWIW.

HarrisonK
Posts: 48
Joined: Sun May 27, 2018 8:20 pm
Location: Main Line, PA

by HarrisonK

JackRussellRacing wrote:
Wed Jun 27, 2018 8:51 am
Delorre wrote:
Mon Jun 25, 2018 1:50 pm
Yours is a 3K one, should be trouble free, as opposed to the UD ones (I cracked 2, Jure confirmed there are issues with those) My replacement is a covered 3K one, and until now, no issues👍

I have probably 15k miles between two Berk 3K Plain Matte saddles, in a variety of horrible/good/great riding conditions, over the last 18 months. Zero issues whatsoever. Both are on Pinarello GAN RS bikes. I'm ~ 63kg, FWIW.
Glad to hear, thanks. Post some pictures of your bikes!

by Weenie


oldturd
Posts: 120
Joined: Thu Oct 06, 2016 12:10 am

by oldturd

JackRussellRacing wrote:
Wed Jun 27, 2018 8:51 am
Delorre wrote:
Mon Jun 25, 2018 1:50 pm
Yours is a 3K one, should be trouble free, as opposed to the UD ones (I cracked 2, Jure confirmed there are issues with those) My replacement is a covered 3K one, and until now, no issues👍

I have probably 15k miles between two Berk 3K Plain Matte saddles, in a variety of horrible/good/great riding conditions, over the last 18 months. Zero issues whatsoever. Both are on Pinarello GAN RS bikes. I'm ~ 63kg, FWIW.
Interesting! i think my experiences are similara to Delorres'- I had a replacement Lupina sent due to clearcoat issues with my first UD saddle, but now the replacement UD has shown signs of clear coat issues. in particular, a strange crack on the clear coat on the top of the saddle. while i will admit the bike did tip over once unfortunately (with the 'wing' of the saddle taking the impact), the top showed no signs of this crack until many days later, so it could have contributed- but am still seeing random peeling here and there (not as bad as my first one!)

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