Author Topic: OIF swinging arm bushes  (Read 412 times)

0 Members and 1 Guest are viewing this topic.

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
OIF swinging arm bushes
« on: 07 November, 2021, 13:02:39 »
Hi Folks, I'm trying to fit new swinging arm bushes to my 71 A65. I got the split bronze bushes in OK but I'm having to apply ridiculous pressure to get the steel sleeves in. I got one just started with a vice but it I can't get it much further. It occurs to me that if it's that tight then how is it ever going to swing so I'm reluctant to go much further.
Any thoughts gratefully recieved.
Thanks Glenn

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #1 on: 07 November, 2021, 15:32:41 »
PS. I did the freezer, hairdryer thing..

Glenn

Ian C

  • Royal Star
  • ***
  • Posts: 192
    • View Profile
Re: OIF swinging arm bushes
« Reply #2 on: 08 November, 2021, 08:52:47 »
Hello Glenn,  The bushes when fitted should have a nominal ID of 1" (25.4mm). The Bobbins or sleeve should have an OD of between 0.9972 to 0.9984" (25.328 to 25.359mm), so I'd check dimensions.

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #3 on: 08 November, 2021, 14:32:23 »
Many thanks Ian I will get the Mic out.

Thanks for the info.

Very helpful

Cheers Glenn

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #4 on: 08 November, 2021, 15:22:02 »
Hi again Ian. I'm slightly annoyed with myself for not thinking of looking in the manual but when I did of course there the dimensions were. Oh well! My Bobbins are .9977 so nicely in the middle. The fitted bush inner Diameter as well as I can measure with my calliper is 25.35-7. I guess the bushes are the problem. not sure what to do about it. Maybe i'll run some 800 wet n dry around in there or perhaps I should look for some guaranteed Harris bushes. I'll let you know how I get on.

Thanks for your help, Glenn

AdrianS

  • Golden Flash
  • *****
  • Posts: 687
    • View Profile
Re: OIF swinging arm bushes
« Reply #5 on: 09 November, 2021, 11:26:32 »
Can you not ream very slightly with an adjustable reamer?

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #6 on: 09 November, 2021, 13:42:58 »
Thanks Adrian, that's an idea but the manual says: "Replacement bushes are pre-sized and when pressed into position will give the correct working clearance. They must not be reamed or machined after fitting." I reckon this was written before the days of variable patent parts! If I was to attempt reaming them I would have to have a line reamer I guess. I'm erring towards getting some different bushes but I have painted the swinging arm now and it will be tricky to do without messing up the paint. Or I might just push on and see if the arm swings when it's all clamped up. Hmmmm

Thanks Glenn

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #7 on: 09 November, 2021, 14:19:48 »
I think I'm going to try honing it a little. I'm not really trying to enlarge it much just to ease it a little I guess it's supposed to be tight but possibly not quite this tight!

Thanks for your help, Glenn

AdrianS

  • Golden Flash
  • *****
  • Posts: 687
    • View Profile
Re: OIF swinging arm bushes
« Reply #8 on: 09 November, 2021, 22:04:39 »
Depends on how much material you need to use. Iíve had to ream bushes that should fit but sometimes when fitting they tighten up . Perhaps if the bushes are very tight to fit, the outside of the bushes or where they fit needs attention before fitting.

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #9 on: 10 November, 2021, 14:03:19 »
That is a good point though I would imagine patent parts are more suspect than original equipment. I did give it a good clean before fitting. Honing seems to be working though it needs a bit more, they are still too tight. I wonder if the advice not to Ream is due to them being split bushes?
Thanks Glenn

GlennA65

  • Star
  • *
  • Posts: 24
    • View Profile
Re: OIF swinging arm bushes
« Reply #10 on: 12 November, 2021, 18:27:48 »
Update: I got a bobbin in but it was still ridiculously tight so I decided to ditch the lot and replace with some LF Harris ones.
When extracting the old ones I noticed some deep scoring on the outside of the bush. On further investigation I found a raised section inside the tube which matched up with some large dents on the outside (see picture). Some clever soul has hit it hard with a hammer at some point and dented it in. I am carefully filing it down inside and I think it'll be ok. I measured the tubes with my rudimentary calliper and they look to be round. I got some good Harris parts on route so lets see if this all works. Fingers crossed!
Cheers Glenn