Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Blog NEW Galleries NEW FAQ Contact About Impressum
It is currently Fri Dec 15, 2017 1:53 am

All times are UTC+01:00





Post new topic  Reply to topic  [ 8 posts ] 
Author Message
 Post subject: srm crank length
PostPosted: Mon Oct 09, 2017 3:57 pm 
Offline

Joined: Sun Nov 15, 2009 12:27 am
Posts: 71
I was wondering if anyone changed crank lengths on the newer srms and did you have to recalibrate? I have a sram 177.5 srm and I'd like to change it to 175 since I stopped doing tt's and put it on my road bike. I know the cranks are the same 3 bolt spider mount like the 900, cx1 or force22 which I have a extra set so that isn't a problem. I tried emailing srm but never got a reply hopefully someone can help?


Top
   
 Post subject: srm crank length
Posted: Mon Oct 09, 2017 3:57 pm 


Top
   
 
 Post subject: Re: srm crank length
PostPosted: Mon Oct 09, 2017 4:37 pm 
Offline

Joined: Fri Dec 24, 2010 9:37 pm
Posts: 1360
Location: it's raining, it must be uk
changing the crank arm on the spider does require recalibration

if you have an accurately known weight you can diy calibrate, i've done this, it's easy enough

or if you have a stable but unknown weight you could 'measure' it on the 177.5mm crank, then swap cranks and use the measurement to recalibrate with the 175mm crank

fwiw when i needed new cranks fitted (the sram three bolt fitting) i sent mine in as i was busy, it was only a week for crank swap, new battery, and recal (this was in the uk, done by scientific coaching who are srm authorised)


Top
   
 Post subject: Re: srm crank length
PostPosted: Mon Oct 09, 2017 4:59 pm 
Offline

Joined: Tue Jan 13, 2009 2:35 am
Posts: 774
When I contacted SRM recently about crank length on track SRMs, I was told that they no longer need to be recalibrated when changing arms. I just had to make sure that the arms were torqued to spec to the spider.

I also did not have to recalibrate my SRM when I swapped arms on my Hollowgrams.

Lastly, if you can't get an email response from SRM, give them a call. US customer service is pretty good.


Top
   
 Post subject: Re: srm crank length
PostPosted: Mon Oct 09, 2017 5:25 pm 
Offline

Joined: Sun Nov 15, 2009 12:27 am
Posts: 71
I was hoping it would be ok if I torqued it to spec and the cranks are the same model. I did the same on my quarq for the cross bike and it was the same after I changed arms, I just had to make sure I used the Loctite and torque they specified.


Top
   
 Post subject: Re: srm crank length
PostPosted: Tue Oct 10, 2017 7:10 am 
Offline

Joined: Fri Dec 24, 2010 9:37 pm
Posts: 1360
Location: it's raining, it must be uk
for mine srm said it needed recal, on return the slope was different, but whether that was due to the crank arm change or simply drift since previous calibration i've no idea!

for diy calibration you can use a spreadsheet or an online calculator such as https://www.cyclingpowerlab.com/PowerMe ... ation.aspx


Top
   
 Post subject: Re: srm crank length
PostPosted: Tue Oct 10, 2017 2:15 pm 
Offline

Joined: Tue Jan 13, 2009 2:35 am
Posts: 774
Sungod, IIRC, it used to be that you had to send them back in for recalibration after changing arms, but my understanding is that some of the newer versions do not need it.


Top
   
 Post subject: Re: srm crank length
PostPosted: Tue Oct 10, 2017 3:07 pm 
Offline

Joined: Fri Dec 24, 2010 9:37 pm
Posts: 1360
Location: it's raining, it must be uk
yes that could be it

mine is c. 2010 vintage


Top
   
 Post subject: Re: srm crank length
PostPosted: Tue Oct 10, 2017 4:23 pm 
Offline

Joined: Sun Nov 15, 2009 12:27 am
Posts: 71
I think mine is 2014 but I will try to give them a call and see what they say.


Top
   
 Post subject: Re: srm crank length
Posted: Tue Oct 10, 2017 4:23 pm 


Top
   
 
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 8 posts ] 

   Similar Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Crank length confusion

[ Go to page: 1 2 ]

in Road

Greatestalltime

19

1733

Tue Jul 18, 2017 1:46 pm

wheelsONfire View the latest post

There are no new unread posts for this topic. Paging Zakeen re: Crank Length

[ Go to page: 1 2 ]

in Road

TheKaiser

20

2345

Wed Mar 15, 2017 11:41 am

gewichtweenie View the latest post

There are no new unread posts for this topic. Crank Bearing Puller for SRM Campagnolo Crank

in Road

mrgray

14

1141

Tue Apr 04, 2017 9:37 am

mrgray View the latest post

There are no new unread posts for this topic. Length of the chain?

in Road

TonyM

9

1088

Sat May 20, 2017 9:24 pm

boots2000 View the latest post

There are no new unread posts for this topic. Reach and top tube length

in Road

cmcdonnell

9

1300

Sat Mar 11, 2017 4:44 pm

mpulsiv View the latest post


All times are UTC+01:00


Who is online

Users browsing this forum: Bing [Bot], Chris3g, gmarsden, jlok, spartan, toronto-rider and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Limited