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PostPosted: Sat Oct 31, 2015 7:05 pm 
Gold Trader
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Joined: Wed Apr 25, 2012 10:36 am
Posts: 6325
Location: In a commune of my own making....
The bike in question, before I go any further (finished pics are on page 3) -

viewtopic.php?f=21&t=335367

After previous discussion, I have gone for 40 x 16, and have to say it seems spot on. However a couple of things I need to check up on....

What is the 'right' position/tension on the singulator thingie, does that look right to you....?

Also, as I happened to have a nice UN72 107mm BB, I've used that, and with the chainring being a fairly big 40T, and for looks, I'm running it on the outside of the spider rather than the middle ring position. Even with the short BB though, this has meant the rear cog has had to go quite close to the outside edge of the hub body to get the chain line spot on, is there any reason to worry about that? (I have considered running the chainring on the middle position, but I think it would be perilously close to fouling the chain stay...maybe...)

Final question (for now!) I have spaced out the rear end with cassette spacers, which is fine, but does anybody make better looking spacers in different sizes and colours? Not the two that come with a lot of kits, I don't think they would work with the current set up....


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PostPosted: Sat Oct 31, 2015 11:15 pm 
Retro Guru

Joined: Fri Sep 07, 2012 12:05 pm
Posts: 272
Location: Auckland NZ
I am running 38 X 19 on the inside of the spider on a '92 Spesh Rockhopper and have gone to a exage crank road crank(exage used the same crank angle on MTB cranks as they did Road) so no small chain ring mounts, with good chain stay clearance, and the rear cog is a good 5-6 mm away from the lock ring.

Looks are one thing, effective chain line is another, I went with a Surly rear cog and a Surly stainless steel 38 tooth chain ring.


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 Post subject: Re:
PostPosted: Sun Nov 01, 2015 12:13 am 
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Joined: Sat Mar 24, 2012 10:45 pm
Posts: 558
The tensioner looks about right. Is the chain slipping a tooth on the rear sprocket when you really put some torque through it ?
Also - is it a recycled 16t sprocket from a normal cassette ? If it's yes to both those then changing to a ss specific sprocket should fix it. The teeth are a different shape & less likely to slip. Mr Control do a cheap kit with a tough and pointy steel sprocket & various spacers for about £15. They're Perfectly adequate and lots cheaper than fancy surly stuff etc.
Regarding the chainring - will it go on the middle position and miss the stay ? It would put less load on the freehub body if you could move the chainline in. Stick the rear sprocket in the middle of the freehub body & eye up the chainline from there with the front ring in the middle. Sod 'looks' - it's a bastard anyway now so it's better if it actually works without ruining the freehub early.

Lastly - mind your knees :wink:


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 Post subject: Re:
PostPosted: Sun Nov 01, 2015 12:28 am 
Gold Trader
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Location: In a commune of my own making....
There's no slipping, and the rear cog is a SS specific thing, looks nice. Having done a bit of research I see there are some nice fancy coloured spacer kits, but they ain't cheap....

Also seems where I have the sprocket on the hub body isn't unusual, having trawled the 'net, but when time allows I will try the chainring on the middle ring position and see whether it gets close to the chainstay. Should add I am only just over 10 st and not exactly a hard rider, and as the chain line looks spot on I wouldn't imagine I could cause too much damage to the freehub body.

Thanks guys for the input! :mrgreen:


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 Post subject: Re:
PostPosted: Sun Nov 01, 2015 7:28 pm 
Retro Guru

Joined: Tue Sep 01, 2009 12:28 pm
Posts: 1420
Location: Almeria, Spain
Liking the Orange very much.

To answer your questions. If you can fit the tensioner to push up rather than down it will give you more chain wrap and less chance of unshipping the chain when standing [your reproductive organs will thank you for it]. :D

I've always fitted the chainring on the outside of the crank [for reasons of bling] with no problems at all. Friends have had trouble with freehub pawls slipping when really honking on climbs. They fixed it by moving the chainring to the middle and then the cog inboard to retain the correct chainline.

There's lots of options re improving the look of your spacers, from using 2.5mm outboard bearing spacers to sawing white plastic pipe to fit. I think your idea of buying a dedicated kit is best though.

Hope this is of help and enjoy the ride. Finally, what are the forks ?


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 Post subject: Re:
PostPosted: Sun Nov 01, 2015 8:04 pm 
Gold Trader
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Location: In a commune of my own making....
Cheers buddy! :mrgreen:

Very helpful, thank you. I'm not a heavy rider as I say, and this is primarily a road going bike with the capability of a bit of off roading if I see a track I like the look of on the way to the pub....

Forks are carbon Merida off here, discussion that I started about them here:

viewtopic.php?f=41&t=334841

Time will tell whether I can live with the light weight of them, ironically the front end feels TOO light, if that's possible :facepalm:


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PostPosted: Tue Nov 03, 2015 10:28 am 
Old School Grand Master

Joined: Tue Oct 09, 2007 1:55 pm
Posts: 9769
Location: New Forest, UK
There is nothing wrong with running the cog at its furthest extent outboard - after all geared bikes are exactly like that!

Off-roading on 40/16 will be interesting...it's amazing the extra resistance from grass or mud.


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 Post subject: Re:
PostPosted: Tue Nov 03, 2015 9:50 pm 
Gold Trader
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Joined: Wed Apr 25, 2012 10:36 am
Posts: 6325
Location: In a commune of my own making....
To be honest, this is a road going MTB that may do the occasional bit of off road on the way to the pub, not the other way around...hence the tyre choice, nothing too knobbly and Land Rover like, noise wise! :lol:

If I had him geared for off road it would make him un-useable for what I really want to do. (Flat lane work, mostly) Probably another reason why I needn't worry about the positioning of the rear sprocket, I'm never going to be powering up hill off road out of the saddle....walking up it, may be....


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