Embarassing bottom bracket question

Bear this in mind before you read

He who asks a question is a fool for five minutes; he who does not ask a question remains a fool forever.

Here goes, i am fitting a cassete type bottom bracket to my wifes claude butler, i have never fitted one of these new fangled jobs Only the old loose/bearings or the race bearing type.

I am unsure which way it goes, (not sure if its the lack of sleep) my repair manual does not help.

I need to know which way the bracket fits, there is no LH or RH on the bracket only a O symbol, and one side has a slightly longer spindle. Does the crank side or the non-crank side have the longer spindle

Also the plastic caps have RH and LH, am i right in assuming that the LH is the non-crank and the RH is the crank ??

I await your laughter

Glad someone else asked on my behalf!

Thank you!!

Its taken me several days, a few Jack Daniels to build up the courage to do so. I have also built the bracket both ways and taken it off again a few times

Don't the cups only fit one way? Therefore you can understand if LH refers to the side of the bike or the thread direction.

In the same boat as you with the long spindle thought.

i assume it's not a shimano B/B because you say the cups are separate? but i assume the bearings are fixed to the axle?

if that is the case and you are not sure which way round the axle goes in i would suggest comparing it to the old axle because assuming you are using the same chainset then the old axle and the new axle should be the same length. at this point i would assemble the old b/b (out of the bike) next to the new b/b and that should then give you a clue as to the correct direction of the axle. by swapping the cups on the new unit you can compare where the cups would fit against the frame to decide on the best orientation of the axle

hope that makes sense and helps

Sorry, i have fitted the cups and as you say they only thread one way. Its just the spindle length which is confusing me

I think its an avec bottom bracket, i have fitted the cups ok. But i have not got the old bracket as i started this build months ago and the old bracket was ruined so threw it away

So it should be ok if i find out which side the longest spindle length goes on

Or maybe i should just buy a new botton bracket kit

Logic (definitely not experience!) suggests to me the longest side is the side which requires the most BB shell clearance which would be the crank or drive side.

My thougths exactly

Quickest way to test is to try it then whip the drive side crank arm and rings on and the measure the distance between the middle chain ring and the Center of the seat tube. If the distance is between 47-50mm you will be fine.