Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: andyoxon on 04 March, 2019, 04:20:00 pm

Title: A-head stem?
Post by: andyoxon on 04 March, 2019, 04:20:00 pm
So my rigid MTB (https://yacf.co.uk/forum/index.php?topic=17.msg2257819#msg2257819) has what I believe to be an early threadless headset and A-head stem(?),  described as a "Dia-Compe Aheadset system".  Anyway, with the 10 degree rise/ 135mm stem i'm a bit more aero than I'd prefer to be so wondered if people can recommend solution and what the best options are.   What are the adjustable stems like and which are good?  I kind of like the idea of being able to adjust it to find the best fit...
Title: Re: A-head stem?
Post by: Brucey on 04 March, 2019, 05:38:51 pm
all adjustable stems are basically junk but some are better than others, and all are handy for setting a bike up.  If you are just going to use it for setting the bike up, it doesn't really matter much what sort you get.

Be aware that the steerer could be 1" or 1-1/8" diameter and also that bar clamp diameters vary.

cheers
Title: Re: A-head stem?
Post by: Blodwyn Pig on 04 March, 2019, 05:57:33 pm
can you not try and get a 135 17 deg rise.   almost....https://www.google.com/aclk?sa=l&ai=DChcSEwism8zAh-ngAhVDsO0KHQ3KD_EYABAFGgJkZw&sig=AOD64_1HLrbqSYbVU2vgRqnm_6FCRGQoTw&ctype=5&q=&ved=0ahUKEwjL5cbAh-ngAhUQTxUIHb61DbcQ9aACCE0&adurl=

assuming yours is 1" being an early one.
Title: Re: A-head stem?
Post by: andyoxon on 04 March, 2019, 06:28:12 pm
Thanks both.  I did wonder whether the adjustables weren't such a good option.  Will check all the diameters.  I wonder if the 17 degree will be enough...
Title: Re: A-head stem?
Post by: Kim on 04 March, 2019, 07:09:00 pm
all adjustable stems are basically junk but some are better than others, and all are handy for setting a bike up.  If you are just going to use it for setting the bike up, it doesn't really matter much what sort you get.

I fitted a Decathlon one to my Reasonably Priced Mountain Bicycle on this logic, and haven't found a pressing reason (other than the knowledge of the gratuitous weight) to get round to replacing it with an appropriately sized rigid one.  I'd probably care more if I used the bike more.

I don't think it's the sort of thing that someone with an n+1 habit would regret having in the spare parts box.
Title: Re: A-head stem?
Post by: Blodwyn Pig on 04 March, 2019, 07:13:11 pm
Thanks both.  I did wonder whether the adjustables weren't such a good option.  Will check all the diameters.  I wonder if the 17 degree will be enough...

ok then 35 degrees. ::-)

https://www.google.com/aclk?sa=l&ai=DChcSEwiz477EmOngAhXut-0KHRZsCBsYABAHGgJkZw&sig=AOD64_26alGppcZGIhFrPZTAY8WJerd14A&ctype=5&q=&ved=0ahUKEwiGh7nEmOngAhWUThUIHUQDAUAQ9aACCFc&adurl=
Title: Re: A-head stem?
Post by: andyoxon on 04 March, 2019, 07:17:50 pm
 
Thanks both.  I did wonder whether the adjustables weren't such a good option.  Will check all the diameters.  I wonder if the 17 degree will be enough...

ok then 35 degrees. ::-)

https://www.google.com/aclk?sa=l&ai=DChcSEwiz477EmOngAhXut-0KHRZsCBsYABAHGgJkZw&sig=AOD64_26alGppcZGIhFrPZTAY8WJerd14A&ctype=5&q=&ved=0ahUKEwiGh7nEmOngAhWUThUIHUQDAUAQ9aACCFc&adurl=

That looks good.   ;)  ;D  Thanks.  Will probably just take a punt and see how much difference it makes.
Title: Re: A-head stem?
Post by: andyoxon on 04 March, 2019, 07:21:52 pm
all adjustable stems are basically junk but some are better than others, and all are handy for setting a bike up.  If you are just going to use it for setting the bike up, it doesn't really matter much what sort you get.

I fitted a Decathlon one to my Reasonably Priced Mountain Bicycle on this logic, and haven't found a pressing reason (other than the knowledge of the gratuitous weight) to get round to replacing it with an appropriately sized rigid one.  I'd probably care more if I used the bike more.

I don't think it's the sort of thing that someone with an n+1 habit would regret having in the spare parts box.

Thanks.  May be worth a shot.  I assume if one follows the Nm tightening they're safe.
Title: Re: A-head stem?
Post by: Blodwyn Pig on 04 March, 2019, 08:31:47 pm
but do check your stem dia before ordering obviously. ;)
Title: Re: A-head stem?
Post by: rogerzilla on 04 March, 2019, 08:59:28 pm
Or just buy a 1 1/8" one, since it's routine to shim them to a 1" steerer where necessary.  I don't think 1" threadless stems are still made.
Title: Re: A-head stem?
Post by: andyoxon on 06 March, 2019, 12:07:06 pm
All measured, 1 1/8" tube, and 25.4mm bars.  I've gone for a EX 120mm 35 degree, so slightly shorter. 

edit.  Installed! Test ride awaited...   :)
Title: Re: A-head stem?
Post by: andyoxon on 08 March, 2019, 08:11:23 pm
Pics showing the difference in stem set-up...   https://yacf.co.uk/forum/index.php?topic=104291.msg2374903#msg2374903

The 19" framed MTB has a 58cm TT, which is actually the same as my 24" frame 531 main bike (120mm quill stem); they both now have the same saddle to h'bars distance...