Irremovable spacer on drive side square taper spindle?

[HovR]

So a few days ago the 25+ year old bottom bracket on my Peugeot finally gave in. I took the old spindle out and measured it up - as it was symmetrical I ordered a direct replacement (UN26).

Now that I've got the bottom bracket fitted in the frame (which was enough trouble by itself) I'm having issues fitting the chainset!

There appears to be some sort of fixed spacer (which I have so far been unable to remove) on the drive side of the spindle, preventing the chainset from seating itself properly. With this spacer in place the chain line is completely off.

The drive side can be seen here (excuse the dirty bike!)

The non-drive side looks like what I would consider normal.

Anyone got any helpful tips? I've worked with sealed BB units before but haven't encountered something like this. Starting to wish I could easily buy another quality cup and cone style unit!

Thanks,
Hov

 

[compo]

I can't help you with an answer but looking at Google Images it appears that some BB's have the spacer whilst others don't. I also found this that while it wont solve your problem may shed a little light.

http://www.bikeradar.com/forums/viewtopic.php?p=16730443

 

[smokeysmoo]

I'm with compo having not seen it before, and I found THIS thread on another site which may help

 

[HovR]

Thanks for the responses guys. I took a look at Shimano's tech docs for the UN26, and whilst this spacer type thing is on the drawings it's not mentioned in any of the annotation or notes at all!

If CC doesn't manage to come up with an answer I might try making an account on roadbikereview and asking 'blakcloud' how he got his off. It's a different brand BB but it may shed some light on to things.

 

[bluemint]

i had one of them on a UN55 which, had I not noticed it, probably would've ruined the crankset. I don't quite recall how I got it off but I may have used 2 flat head screwdrivers either side to lever it off. But off it came.

 

[HovR]

Just tried that and the screwdrivers were going to bend before this spacer thing came off - and these were some pretty chunky ones too. What ever it is, it's on there tight.

 

[classic33]

Just tried that and the screwdrivers were going to bend before this spacer thing came off - and these were some pretty chunky ones too. What ever it is, it's on there tight.

Gear puller?

 

[compo]

Have you got anywhere with your BB?

 

[fossyant]

Peugeot and BBs .. I doubt they are BS threaded. Is the BB UN26 French..?

Never bothered with anything under UN5x series for the price. Need to know what the chain set is as well.

 

[HovR]

Have you got anywhere with your BB?

Unfortunately not, compo. I've been using my Hardrock Comp MTB with road tires at the moment as I haven't got it working.

Peugeot and BBs .. I doubt they are BS threaded. Is the BB UN26 French..?

Never bothered with anything under UN5x series for the price. Need to know what the chain set is as well.

Fairly sure the BB shell is British threaded, as the fixed cup is a left hand thread, whereas french threaded frames have a right hand thread for this cup. Also the BB is definitely British threaded, and that went in fine once I'd cleaned the old dirt out of the threads in the frame.

The chainset is the original Nervar chainset. Figured the UN26 would be fine for £7, even if it didn't last as long as the better models, however this spacer thing makes it completely unusable on my crankset, which I didn't expect from Shimano!

 

[RecordAceFromNew]

So a few days ago the 25+ year old bottom bracket on my Peugeot finally gave in. I took the old spindle out and measured it up - as it was symmetrical I ordered a direct replacement (UN26).

Have you still got the old BB spindle and what is the code on it and what is the code of the new UN26?

 

[Graham]

On that basis that you can't blowtorch the spacer to get it off, you could try freezing the spindle so that it contracts a bit. The spacer may then pop off ok. I thought of something like a pipe freezing kit that you use for radiators. Kit might be more expensive than the BB though.......

 

[RecordAceFromNew]

On that basis that you can't blowtorch the spacer to get it off, you could try freezing the spindle so that it contracts a bit. The spacer may then pop off ok. I thought of something like a pipe freezing kit that you use for radiators. Kit might be more expensive than the BB though.......

I suspect the OP has bought an asymmetric UN26 BB - in terms of the distance from spindle end to cup. I further suspect left distance is approximately the same as the distance up to the "spacer" on the right, hence why it is there - suitable chainset is not supposed to go near let alone further. I further further suspect the new BB doesn't match his chainset hence my earlier questions, Just speculating, like.

ps Nervar chainsets, being French, likely designed to mesh with ISO, not JIS taper too.

 

[HovR]

Have you still got the old BB spindle and what is the code on it and what is the code of the new UN26?

The new Shimano BB is labelled "LL123, Shimano BB-UN26, 68GH, BC 1.37x24". It was sold on CRC as a 122.5mm BB, so .75 longer on each end than the previous 121mm BB (it was hard to find a direct replacement).

The original spindle is labelled 121mm length, "TTS".

I was under the (probably incorrect) assumption that my crankset would be JIS. Is there a foolproof method for identifying whether it is or not?

Thanks for the response.

 

[HovR]

Well, after a bit of fettling I've got it in to what appears to be a working state.

Previously I was only running one chain-ring in the outer position of a double chainset. As RAFN suggested, my chainset is most likely ISO which moved it out 4.5mm on the JIS bottom bracket (still haven't figured out what that spacer is for, but there seems to be enough taper interfacing with the crankset despite it).

To combat that I moved the chain-ring to the inner position on the chainset, putting it back to roughly the right chain line. The outer chain ring position is now useless as it's too far out, but that doesn't bother me too much. It seems to shift well from the testing I have done so far.

It's not the perfect solution, but as this is just my around-town bike, if it works I'll keep it. If it doesn't work I'll just replace the lot with a new JIS chainset and matching bottom bracket to get it over with.