I picked up a nice blue 800 with lefty earlier this year and I am working through all the jobs on it.

the BB has seen better days – it is creaking and has a little play it in and feel rough so I am binning it.

I do have spare new External BB chainset from a Rize and when I fit it the crank arms foul the rear suspension, is is possible to “pack out” with shims the arms to make it work?

1 side or both? Maybe move shims from 1 side to the other.

I put the BB on with no shims = so I will try again and see what happens

this is it cathes with no shim – non drive side, the drive side is fine

and weith a shim

success! it doesnt miss by much – but it does clear now

and now it looks completely different compared to the skinny coda/middleburn set up

Just need to decide now Silver chain or gold chain – I think silver

One assumes sir won’t be riding in mud/anything but dry weather.

Else that paint won’t last long

Ah. Man I’ve got one of those frames hanging up in the shed…

That “clearance” is way too small, shirley!

Mud, crank flex under load, other scenarios etc.

Maybe I’m stating the obvious, but shouldn’t that BB have a top-hat cover over the bearing? Did you refit it after the photo? Without it the width will be off and your bearings will die quite quickly.

Secondly, is it a 68mm or 73mm BB? 68 should have 2 drive side spacers and 1 on the non-drive side. 73mm just 1 spacer on the drive side. If you’ve added extra spacer onto a 73mm BB then the crank axle will be too short.

Thirdly, that’s far too little clearance. The frame and/or crank will flex and there will be a clash!

so the coda cranks will have to back and I will get a new BB for it!

the old one was 68