Retrobike Forum Index

It is currently Sun Dec 11, 2016 3:55 am

* Login   * Register * Search  * FAQ



Post new topic Reply to topic  [ 577 posts ]  Go to page Previous  1 ... 22, 23, 24, 25, 26, 27, 28 ... 58  Next
Author Message
PostPosted: Mon Aug 12, 2013 5:19 pm 
MacModerator
MacModerator
User avatar

Joined: Fri Jul 14, 2006 8:59 pm
Posts: 20774
Location: Sol Kitts
I think its because most people use the middle chainring position to achieve the desirable chainline. 32t generally being the smallest middle ring size.


Top
 Profile  
 
PostPosted: Tue Aug 13, 2013 7:53 am 
Retro Guru
User avatar

Joined: Tue Aug 07, 2007 12:22 pm
Posts: 2942
Location: Platsa, Messinias, Greece
kaiser wrote:
I think its because most people use the middle chainring position to achieve the desirable chainline. 32t generally being the smallest middle ring size.

Yes, this probably, although if you're using a normal cassette type hub you should be able to move the sprocket in far enough to achieve a correct chainline with the granny ring position. If you're using a freewheel or a single speed cassette type hub (like Hope or Chris King trials/SS) then you might not be able to get the sprocket inboard enough, as the wheel has less dish.

Another thing to consider is that, for a given pressure applied at the pedal, chain tension is higher the smaller the sprocket/chainring sizes become, resulting in higher tooth loading just when you have fewer teeth engaged with the chain anyway, so more wear, less smoothness.
It hasn't been a problem to me with a my 28T HBC chainring, which is pretty much as good as new after two years, but I'm old and pretty mediochre in my power output.
Hopefully you're not.....


Top
 Profile  
 
PostPosted: Tue Aug 13, 2013 7:51 pm 
aka Leo Swayer
aka Leo Swayer
User avatar

Joined: Wed Jun 18, 2008 7:15 pm
Posts: 6365
Location: Wales.UK
I think i'll give it a whirl then :D


Top
 Profile  
 
PostPosted: Wed Aug 14, 2013 11:53 am 
Retro Guru
User avatar

Joined: Thu Jul 26, 2007 11:22 am
Posts: 351
Location: Sideways in Wellington, New Zealand
Grannygrinder wrote:
This old thing still needs a frame repair but sooner or later it will be my main rider :D
Currently on 18-30 gearing as the hills are 'significant' around these parts :wink:


I take it this has now been repaired and it will have the discussed gearing applied to it?


Top
 Profile  
 
PostPosted: Wed Aug 14, 2013 5:46 pm 
aka Leo Swayer
aka Leo Swayer
User avatar

Joined: Wed Jun 18, 2008 7:15 pm
Posts: 6365
Location: Wales.UK
Work in progress.
Its a ti frame and i know a man who can repair it, but not for a while.
I will probably go for 26-14 and see how i find it.
No rush though i've got plenty of other things to ride :wink:


Top
 Profile  
 
PostPosted: Wed Aug 14, 2013 8:27 pm 
Retro Guru

Joined: Sun Jun 20, 2010 4:39 pm
Posts: 1455
the finished (for now) klein rascal ss
Image


Top
 Profile  
 
PostPosted: Sun Aug 18, 2013 3:17 pm 
aka Leo Swayer
aka Leo Swayer
User avatar

Joined: Wed Jun 18, 2008 7:15 pm
Posts: 6365
Location: Wales.UK
I decided to bite the bullet on set it up(even if i can't ride it yet :D ) for 26-13 using the grannyring on the front.
There is something very satisfying as the cutting disc slices through your M960 crankarm :shock: :lol: :lol:
Chainline is bang on with 8mm of spacers inside(spokeside) of the rear sprocket and as the sprocket is so far inboard there is even less chance of chainslap on the chainstay as the only section of overlap is right near the front sprocket.
22 tooth is fited at the moment as my 26t hasn't arrived yet, i will also fit stell chainring bolts as the alloy ones would be foolish!
So in theory i am really happy, as to how it rides i'll have to wait and see :D


Attachments:
xtr 001.JPG
xtr 001.JPG [ 92.17 KiB | Viewed 805 times ]
xtr 002.JPG
xtr 002.JPG [ 80.92 KiB | Viewed 805 times ]
Top
 Profile  
 
PostPosted: Mon Aug 19, 2013 7:37 am 
Retro Guru
User avatar

Joined: Tue Aug 07, 2007 12:22 pm
Posts: 2942
Location: Platsa, Messinias, Greece
Grannygrinder wrote:
Chainline is bang on with 8mm of spacers inside(spokeside) of the rear sprocket and as the sprocket is so far inboard there is even less chance of chainslap on the chainstay as the only section of overlap is right near the front sprocket.


Surely chainslap is never an issue on a singlespeed anyway? It's one of the attractions of SS and IGH bikes.


Top
 Profile  
 
PostPosted: Mon Aug 19, 2013 7:54 am 
aka Leo Swayer
aka Leo Swayer
User avatar

Joined: Wed Jun 18, 2008 7:15 pm
Posts: 6365
Location: Wales.UK
I was 99% sure it wouldn't be a problem, but with such small rings and with the chainstays on this frame being quite chunky i was a little concerned, i needn't have been :D
A couple of friends who SS alot have raised concerns about wear rates but when you compare the cost of middle rings(about £45 minimum for these cranks :? ) and take into account that a stainless steel 26t inner is about £8 i'll still be quids in if they wearout 4 times as quickly :lol: Also all the miidle rings for these cranks are aluminium meaning that they aren't really the ideal choice for SS.
I've fitted a Gusset 13t rear sprocket with quite a wide footprint on the freehub to spread the load, a Hope trials hub would be nice but funds won't allow it at the moment :roll:

I have all the torque of a lettuce so i don't see wear being a problem :D


Top
 Profile  
 
PostPosted: Mon Aug 19, 2013 10:49 pm 
Gold Trader
Gold Trader
User avatar

Joined: Sat Aug 18, 2007 12:28 pm
Posts: 3361
Location: The Admiral Benbow
so I built a singlespeed for the summer. the frame was karma from here the rest of the parts I had to hand, threw it all together and came up with a rasta bike. I was enjoying it so much that ive not used my other bikes for a while.
then I saw the haro in the 98 section :D took it for spin to see what it was like and ended up taking a 6mile detour in the pouring rain on the way home, need to upgrade the brakes befour a serious ride but I really like it.
side by side they are identical bikes the only difference being the size and the disks


Attachments:
12653_10151803041488588_1070001106_n.jpg
12653_10151803041488588_1070001106_n.jpg [ 83.92 KiB | Viewed 772 times ]
IMAG0148.jpg
IMAG0148.jpg [ 109.4 KiB | Viewed 772 times ]
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 577 posts ]  Go to page Previous  1 ... 22, 23, 24, 25, 26, 27, 28 ... 58  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: No registered users and 2 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:  

About Us

Follow Retrobike

Other cool stuff

All content © 2005-2015 Retrobike unless otherwise stated.
Cookies Policy.
bikedeals - the best bike deals in one place
FatCOGS - Fat Chance Owner's Group

Powered by phpBB® Forum Software © phpBB Group