Non flush LH cup on shinmano BB

[bertgrower]

there is a third (and more obvious) possible issue, in that removing the last 2.5mm from the BB shell may start to remove the useful part of the chainstay attachment welds (esp in a TIG welded Alu frame) or even parts of the chainstay itself.

Any frame warranty you might think you have will almost certainly be voided by chopping the end of the BB shell.

There are other possible solutions to your dilemma, depending on what you are trying to do exactly; are you running derailleur gears and if so what type? Is it a repair, a modification or a fresh build? Do you have new bits (that can be exchanged perhaps?) or used parts to work with?

cheers

It a new frame

I running a triple new

Derailleur long arm new

Front derailleur is 47.5 to 50 mm new

[Brucey]

if you are sure that the chainset needs a 103mm BB to give the correct chainline, I would recommend that the easiest solution is that you get a different chainset.

cheers

[bertgrower]

[quote="Brucey"]if you are sure that the chainset needs a 103mm BB to give the correct chainline, I would recommend that the easiest solution is that you get a different chainset.

cheers[

Yes, that is the conclusion I came too.

Many thanks for your help.

[bertgrower]

Update

See photographs

The frame is a Pinnacle , the mans version of the one below.
https://www.evanscycles.com/pinnacle-li ... e-EV202523
The bottom bracket shell has no holes access to the chain stays. It is a plane tube

The bottom bracket shell is 73 mm wide has cause difficulties with selection of the bottom bracket cartage when the length required for the chainset is 103 mm with a 50 mm chain line.
The shell has wide shoulder and hence suitable to for the reduction of the width to the fitting of a 68 mm bottom bracket cartage.

They will be no interference from the cranks or chain rings

I ask Evans Cycles they could see nothing wrong with what I wanted to do but they could not reduce the width, they said they did not have the tool suggest I contact a frame builder.

I contacted a frame build I knew (see below) he said that no problem done many times.
We can arrange to pick up the frame for London
Geoff Roberts Frames,
Unit 4 Green Man Yard,
Boreham Street,
Hailsham,
East Sussex,
BN27 4SF
07840 786100
geoff@geoffrobertsframes.co.uk