[Bikerpunk241]

So, I finally got my parts, I was assured that I needed the Howitzer 73mm shell with a 56mm chainline. However, this sets my cranks cm's (yes plural) away from the frame. Question is, those of you who have Socom's (if any), if you built it with a Howitzer, what size did you use? I'm gonna try the 51mm chainline tomorrow, but it looked to me like I needed to loose more than 5mm on either side.

 

[brocelif]

I have the same setup. It looks wide but fit perfectly with an e13 chainguide. Do you have the socom already?

 

[Bikerpunk241]

Yeah, and actually found one that will work. I used the 73 with a 51mm chain line. Thanks.

 

[davep]

It actually depends on what rear you have on your Socom. The 135mm rear requires the narrower chainline. The 150mm rear requires a 56/57mm chainline.

 

[Bikerpunk241]

I have the 150 rear.....and the 51 chainline.....works perfect.

 

[?????]

I'm about to buy another Howitzer bb for my Socom with a 150mm rear. Which size is supposed to be on there? 73mm shell with 56mm chainline?

 

[Dogboy]

I have the 150 rear.....and the 51 chainline.....works perfect.

But it doesn't. A 49-51mm chainline is built around 135mm rear spacing. 150mm rear spacing uses a 56-57.5mm chainline. It's just simple math. You could get a reasonably close chainline with the BB you are using by installing the chainring on the outermost position of the spider - assuming you are using a chainguide like the LG-1.

 

[JohnnyC]

But it doesn't. A 49-51mm chainline is built around 135mm rear spacing. 150mm rear spacing uses a 56-57.5mm chainline. It's just simple math. You could get a reasonably close chainline with the BB you are using by installing the chainring on the outermost position of the spider - assuming you are using a chainguide like the LG-1.

You are right, but seeing as it's an Intense I wouldn't be surprised if the dropouts weren't straight

 

[DirtyMike]

But it doesn't. A 49-51mm chainline is built around 135mm rear spacing. 150mm rear spacing uses a 56-57.5mm chainline. It's just simple math. You could get a reasonably close chainline with the BB you are using by installing the chainring on the outermost position of the spider - assuming you are using a chainguide like the LG-1.

This is correct, 150 rear on teh socom needs a 56/57mm chainline BB for the howitzer.

 

[tatankainlondon]

You are right, but seeing as it's an Intense I wouldn't be surprised if the dropouts weren't straight

Hehe, good one

 

[Jonny5]

It may be the case, but many bikes use a 51mm chainline on a 150mm hub without issue. I've seen many socoms running xt or xtr cranks. And I've set one up for a customer with a pair of standard hone cranks. Works fine. I have also run my norcos with the same setup for 3+ years now. Chains dont drop, wear faster. All is sweet.

 

[DirtyMike]

If they are running something like an LG1, where you can run your chainring on the outer position I can see it working fine, but if your running something with the chainring still inboard on the cranks, then you will wear the chain, and derailer prematurly.

Most people that DH, chain wear wont be an issue, In my experience they replace there chains on too regular of a basis to notice.

 

[Bikerpunk241]

The problem I encountered with the 56mm chainline, was that the chainguide had to be spaced out the 6mm from the frame to get it aligned, with the 51mm, the guide bolted straight to the frame. No issues with shifting or back pedaling with the narrower spacing and a 150 spacing rear end.