Rear springs upper fixing

Ducvelo

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On my twin, the F57/2s sleevesare jammed/rusted in the UFM. Any bright ideas on getting them out? I've tried drilling, but they seem quite hard for an HSS drill. Or does it not matter - the previous owner had fitted a longer F28/1 shaft with lock nuts on the end, and this rotated. Is this the best solution, or should I persevere with trying to get the F57/2s out. Is the design that the OD of the F57/2s rotate slightly in the UFM as the RFM pivots - but the F57/2s appear to be steel and there aren't any bushes. How do they get lubricated? Or is this the problem?
Any thoughts greatly appreciated.
 

davidd

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I turned a steel drift in the lathe so I could tap or pound them out. If they are seized too solid to move all you are doing is expanding the sleeve in the UFM if you pound it too much. Pressing it out is an option, but an unlikely one for you right now (as is the application of heat). I would just spray it with Croil, or the equivalent, regularly to see if it will loosen up by fall if you are not in a rush. When it comes out I would install the new one with some NeverSeize.

I do not think it was designed to turn. Others may know more than I, but as a sidecar enthusiast, I would note that there is a three spring set-up that replaced the damper with a spring. In this set-up, the three springs needed more clearance than was possible with the sleeves used for the damper. This utilizes a longer F28/1, which is really an F28/3. Also used are two F57/4 sleeves which hold the outboard springs out further. On the RFM you have a longer bolt, F28/4. Then there are two sleeves, FT272 to hold the outboard springs out further on the RFM. Finally, There was SP5AS, which was a spacer and a special spring box eye to fit over the spacer so that the center spring was more securely supported.

I do not know if these parts were ever produced, or produced in small quantities, but I think that the sleeves were a design feature that allowed the flexibility to fit these items.

David
 
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greg brillus

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The sleeves should rotate in the bosses at the rear of the upper frame. And making up a stepped drift as David suggests is a good one, although you really need to support the other side with a piece of tube and a dolly ( heavy piece of steel ) to absorb the hammer blows.....perhaps a better and less destuctive idea might be to make up a simple puller using some threaded rod and suitable spacers, drown the whole assembly in some form of penetrant oil beforehand to help the removal process. Once removed just clean up the bores with a strip of emery tape inserted through a slotted piece of round rod, and spin in a drill. The new bushes will most likely be of stainless, but check that they are longer than the width of the boss when installed.....Just lube nicely with grease, and assemble. Once the whole assembly is together and the nuts tightened, both spring box's and shocker unit should pivot up and down freely. And in future, at periodic maitainance, a drop or two of oil will keep the bushes lubed and free from seizure........Cheers for now.......Greg.
 

ossie

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get a dremel type grinder and carefully grind it through across the bush when its nearly through get a small chisel or screwdriver and curl it inwards make two grooves if you have to.
that's unless you.ve done it.
 

Ducvelo

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Thanks for all the suggestions. I'll have a go this weekend and let you know how I get on.
 

Ducvelo

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Just to say, I got this sorted over the weekend. Judicious use of penetrating oil, the right sized drift, and some special sized spacers to go in the gap in the centre but right diameter for the bushes and I got both F57/2s out. Cleaned up as suggested, and now ready to put spring boxes back on properly. Thanks for the help.
 
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