BB/ crank/chainring problem

My crank on the drive side seems to be able to screw on way too far to the bb spindle, to the extent that the chainring can scrape on the chainstay if I screw it on too far. I have screwed it on as far as I can without it scraping, but it doesn't seem to be on very tight at all, and I am a little worried about it coming loose. It's a charge plug btw. Do I need a spacer of some sort, or should I use loctite, or is it just broke? Any thoughts please.

sounds like the BB is too short, or if it has previously been correct then maybe the cranks are worn/cracked and are going on further than they should. The bb taper could also be worn, except this will be steel where the cranks are aluminium and more likely to wear first.

Providing it is a square taper set up?

+1, for spindle too short
although if square taper, both crank and BB need to be both JIS or both ISO taper.

Which crank and BB are you using?

Is this a new installation?

Yep, it's square taper. I was overhauling two bikes at the same time a while ago, maybe I accidentally swapped the bbs over! Doh.

Which crank and BB are you using?

Is this a new installation?

It's the stock that came with the plug, can't remember what though.

Yep, it's square taper. I was overhauling two bikes at the same time a while ago, maybe I accidentally swapped the bbs over! Doh.

sounds likely!

sounds likely!

Not really.

Standard BB on the Plug is 103mm. Not many axles shorter than that!

maybe you're trying to fit shimano onto campag taper.

no, i don't have any campag. If only!

Does the left side arm appear to be further from the chainstays or BB than normal?

If this is the same spindle, could it perhaps have been inserted the wrong way?

Daft question: Plug has Sugino RD cranks AFAIK. Is the chainring on the inside? If so , swap it to the outside.

Agree with Kowalski, but possibly not with dmczone: Sugino 103 BB has one cup fixed to the BB and threads are opposite so it is unlikely that it is the wrong way round.

Sounds like a very worn right crank. Have you removed it before?

It's the stock that came with the plug, can't remember what though.

Is this your BB?

@dmczone: that's what I have. Right side cup is fixed to BB.

I don't think that it was branded 'sugino', but the right side cup was fixed to the bb. I thnk it was branded RPM, but I'm not sure. Tomorrow I'll take it back out and have another look.

The chainring is on the inside, so i'll see if i can put it on the out. Also I'll check whether I can install the bb the other way round or not. I have removed the crank before, but I don't know why it would be worn as the cranks was stock and I got the bike this January. 2007 model, methinks.

Thanks for the input so far.

Put the ring on the outside - sorted.

The chainring is on the inside, so i'll see if i can put it on the out.

Thanks for the input so far.

Was removing the chainring part of your overhaul?

In the future a quick photo when possible might allow for a quick answer.

Standard BB on the Plug is Tien Hsin Industries 7420, which is branded RPM.

Drive side cup on these is fixed, so not really possible to install arse about face.

Bingo - i'd been foolish enough to replace the chainring on the wrong side. All is well now, thanks all.

I don't think that it was branded 'sugino', but the right side cup was fixed to the bb. I thnk it was branded RPM, but I'm not sure. Tomorrow I'll take it back out and have another look.

I just installed one of those, and under the sugino sticker it was labelled as RPM.

the sticker on mine must have come off then

"i don't have any campag"

sugino is campag TAPER.

"i don't have any campag"

sugino is campag TAPER.

That one ain't.

Only Sugino NJS is ISO.

oopS!

i meant sugino 75.

soz. as you were.

"i don't have any campag"

sugino is campag TAPER.

nope, rd is jis.