Author Topic: Bump rubber replacement  (Read 4576 times)

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Offline evo550

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Re: Bump rubber replacement
« Reply #15 on: May 07, 2009, 02:36:33 pm »
Doc,
If you slice it on one side and and wrap around shaft then glue it together as soon as shock bottoms on bumper it will split open again as the stop gets compressed.
No short cuts allowed ;)
Also, if stops are  old enough to have perished, what condition is the oil/gas in the shocks....well past thier use by date I'd imagine.

DR

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Re: Bump rubber replacement
« Reply #16 on: May 07, 2009, 04:11:16 pm »
Evo the shocks are my original '78 RM400 and '78 RM125 units. They are definately old but still very nice and for my type of riding they work perfectly fine, there are no other problems except the rubbers so the cost outweights the benefits when I ride the bike for maybe an hour once a year. In a perfect world I'd like to have them all rebuilt but in practicle terms the TM125 is my main ride bike so that's where I'd spend the money. With a little collection happening I've already had to replace 40 or so shocks in the past few years. Add that to all the multitude of new tyres, new cables, chains, sprockets, etc and you'll begin to see why I need to spread my minimal funding thinly. 'IF' I had just 1 or 2 bikes then yes, they would be the super bling machines but I would be bored out of my head with nothing to do except look at them :( I have a plan and if it works it'll be great and if it doesn't work, well I haven't lost anything. I understand perfectly well where you are coming from though and yes, I'd thought of the splitting also but they are kinda contained ;)     
« Last Edit: May 07, 2009, 04:13:57 pm by Doc »

Offline asasin

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Re: Bump rubber replacement
« Reply #17 on: May 07, 2009, 04:55:59 pm »
I rebuild my RM kybs myself .a bit fiddley but not brain surgery, you need to have access to a tig to put the top back on.Cut the top off preferably in lathe .undo inside . remove shaft , replace seals, clean etc and reassemble , tig top back on fill with oil and done.
If in doubt ,WIND IT OUT

DR

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Re: Bump rubber replacement
« Reply #18 on: May 07, 2009, 05:15:39 pm »
yeah, that would be nice John and I wouldn't mind a new challenge but for mine they don't need the rebuilding and if I touched them then would most surely need replacing not rebuilding :D it's just the dang bump stop perished is all ::) be an easier pill to swallow if the gas and dampning were totally shot but it's not ::) I'm off to have a look at a few urethane items tonight that may or may not work ;) you coming over for CD6?

Offline asasin

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Re: Bump rubber replacement
« Reply #19 on: May 07, 2009, 06:58:54 pm »
True no point in pulling them apart if ok.I have used nolothane from car suspension joints in one of my cooper shock sets . I did what you said and cut them and re glued (good old supa glue), as they were hard to start with they havent split (yet)and even if they did they wouldnt fly apart I Lathed them to fit just inside the springs.its good stuff that red nolathane .Yea I am coming to CD6 Doc (doing the second honeymoon thing, only way I could swing it ;D)will be flying in Thursday out Tuesday spending Friday and Saturday near the track.Will see you then.
If in doubt ,WIND IT OUT

DR

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Re: Bump rubber replacement
« Reply #20 on: May 07, 2009, 07:56:35 pm »
sounds good bloke will seeya there for sure ;) also the bump stops I'm looking at are slightly bigger OD than the springs ID so I hoping to do the same kind of deal with having them an interference fit to stop the split. I was just looking at the stock rubbers and jeez they're piddly little soft things, no wonder they're rooted ::)

lms6201

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Re: Bump rubber replacement
« Reply #21 on: May 08, 2009, 04:58:17 am »
my 465 yz has a sikaflex bump stop , i used a toilet roll core and some tape for a mould , bike ridden rarely but , and it is only a temporary thing