Is this right? strange bottom bracket issues..

Re:

Hya..well with the BB un71 it is the right side collar that comes off...I`ve checked out other photos of it on google to make sure. I`ve followed the arrows to fit left to right so it should be in the right way hopefully ; )
 
Re: Re:

LeePrice":30fy86f6 said:
Hya..well with the BB un71 it is the right side collar that comes off...I`ve checked out other photos of it on google to make sure. I`ve followed the arrows to fit left to right so it should be in the right way hopefully ; )

It's the left side that comes off (has no lip on it)
The right side of a bike is the drive side/chainset& gears.

Sometime the lipped side (the drive side and also in its correct position as shown) can come.off.on these older bottom bracket. Quite useful and.easy to do.
but it does mean you have to out the bottom bracket in the correct way around.

As long as R was fitted to the lipped cup, you are fine.

take it out and double check, how far in is the left/none drive side cup into the frame?


P.S personally i think that may be back to front as the DL-N stamp is usually on the drive side and covered by the lipped cup to make it hard to read when fitted.
Still a lack of visible cup, did you measure the frame shell itself?
 

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Re:

edit seen the other pic.
bottom-bracket.jpg


other than the wrong cap.is off for fitting that looks fine.

take the other cap of and push the drive side one on fully. I would make fitting easier.
 
Yep, like above, right side has lip and tightens against frame, left has no lip and tightens against bb itself.
 
mk one":2q3cab5e said:
Yep, like above, right side has lip and tightens against frame, left has no lip and tightens against bb itself.

Yes...it`s gone in that way as shown in the photo..should that be right?
 
LeePrice":2tswpk4h said:
mk one":2tswpk4h said:
Yep, like above, right side has lip and tightens against frame, left has no lip and tightens against bb itself.

Yes...it`s gone in that way as shown in the photo..should that be right?

Not as in your photo.

but in the end it doesn't matter as long as they are against the cup ends at both side. it's just much easier the original way around.
https://si.shimano.com/#/en/search/Keyword?name=un71
 
Re: Re:

FluffyChicken":3d3gqqva said:
edit seen the other pic.
bottom-bracket.jpg


other than the wrong cap.is off for fitting that looks fine.

take the other cap of and push the drive side one on fully. I would make fitting easier.

oh...we fitted the bottom bracket by pushing it in left to right and tightening a little...then tightening the right side until the cap was flush with the frame..then tightened the left up.

Should we be pushing it in from right to left with the left cap off...tightening the drive side up and then the left side?

Sorry for any confusion..it`s not easy to think or put it in easy terms..

Lee
 
Re: Re:

FluffyChicken":awaxh7id said:
edit seen the other pic.
bottom-bracket.jpg


other than the wrong cap.is off for fitting that looks fine.

take the other cap of and push the drive side one on fully. I would make fitting easier.

Just to clarify I had real trouble putting the BB in and tightening it at first..the left side would tighten up but then the right side cap wasn`t flush with frame. So the last ime I put it in from left to right but fully tightened up the drive side first until the cap was flush with the frame..then tightened up the left side. The left side would keep going in and in the frame until it tightened up.
I rode it the other day and the BB does seem to be fine. My issue is that the spindle length is not symmetrical/equal on both sides..it does seem to be much longer on the right side. Is that something that you have come across? I can`t get the first gear at all at the moment but then the barrel adjuster is broken completely. Maybe fitting the new RD may make a difference?
 
Have you got a 68mm BB in a 73mm BB shell? That would cause the unequal spindle either side. As for not getting 1st gear, might be obvious but have you adjusted the stop screws correctly?
 
benjabbi":39bwwkjl said:
Have you got a 68mm BB in a 73mm BB shell? That would cause the unequal spindle either side. As for not getting 1st gear, might be obvious but have you adjusted the stop screws correctly?

oh..I`m not a technical person...when you say shell do you mean the part of the frame the bottom bracket goes into?...should I measure that? I was told the BB had to fit the chainset, which it should ; )

Yes there is a problem with one of the limit screws not doing anything..I have a replace RD on the way..
 
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