R1 Shock Snapped !

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RinB
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I can confirm that this is the second one to go over the period

The one at the Euro had gone in same place, guy bought it over to me to see if we could weld it, but sorry to say we couldnt as steel shaft threaded into alloy.

Ive been using these for years with PTFE type bushes and it does make you think.
But mind you I did free the internals off (sanded down) so I could get the shock on & off easier

Smiffy
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soullad
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Jaime - yes i too thought these were the answer but maybe they aren't?..................
As I and others have stated these have been used for a number of yrs now, so is this just unlucky or the tip of an iceberg?
Either way, ptfe, brass or urethane are too solid a product for the job, and unfortunately i do not believe that there is enough room left in the top or the bottom aluminium housing on the r1 / r6 design to fit any useful depth of rubber into - theres certainly not enough meat left to drill a larger diameter hole. Whatever product you use there has to be enough "give" inherent in the material to allow flexing in all axis.
By that I mean that if you remove your rear shock the engine can actually move side to side fractionally too ....thanks to the rubber in the engine mounts. This side to side movement is also possible in the rubber rear shock mounts too. It cannot be possible in urethane, ptfe or brass obviously as they are too hard a product. In effect the traditional lammy rubber mounted set-up allows movement in all axis.
I guess when Innocenti were developing and testing the different rubber densities it came down to a compromise between allowing flex / rotation and stiffness. I can imagine that the engine mount actually took alot more design and testing than we probably give it credit for.....
This is probabaly why the Clauss Studio solid engine mount urethane bushes have since been proven to be too tough for the job.? and maybe now the converted rear yam shocks?
Knowledge
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My Abarth has nylon bushes that slip into the shock and allow rotational movement. I identified the side to side movement of the spring when I was building up the shock a with the 180lb spring, and built a spacer to centralise it. I don't feel that my shock is in danger of breaking.

Nylon bushes are interesting. Remember how the small nylon bush between the standard carb and the manifold can wear the manifold, creating a lip and occasionally a leak. You wouldn't expect nylon to be harder than ali, but sometimes it is.

Perhaps the R1 shock is still the answer, and the real danger is our inappropriate adaptions to make it fit.
Martin
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tony
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Indeed. Next time anyone fits one try this. fit shock with no spring. loosen engine bolt and check movement. Is it free? Does motor swing easily(albeit against the damping)?
If not there is an issue as Martin said in the adaption. Even a roller needle type bearing would be better than locking it up(though vibration would be an issue). I like the top hat idea. Poweflex use this system on their bushes for car suspension.
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stageman
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soullad wrote: This is probabaly why the Clauss Studio solid engine mount urethane bushes have since been proven to be too tough for the job.? and maybe now the converted rear yam shocks?
Whats wrong with the Clauss Studio engine mounts ? Have just fitted a set to the motor i´m rebuiliding....
soullad
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Knowledge wrote:My Abarth has nylon bushes that slip into the shock and allow rotational movement.
Martin - you saying that your nylon bushes rotate within the shock mount and around your frame / engine mounting lugs....... this cannot be good can it?
Also how is this possible surely the top hats are compressed slightly and held solidly when you tighten the nuts up?
Supereibar
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Ian, you made a very interesting point regarding Innocenti's compromise with rubber mount stiffness on rear shocks. Considering you could have injured yourself, perhaps there is just so much we can made ever lasting, and the rest is just taking it too far. Maybe as Martin says the approach is correct, but we are doing something wrong, considering that you just broke a shock meant to held a machine that weights three times a Lambretta. Would you beleive softer rubber (like original engine mount rubber) would be a better solution as oposed to nylon? So that we would have to replace it every six or eight months of use, depending on how ofter it is used? I don't understand very well the other problem you mention, aparently the shock compressing plate represents another issue that has no solution?

On a personal basis Ian, I think we might be better off fitting a hagon on our racer.... You think?

Jaime
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just got back from a few weeks away with work then a trip to france . and as a supplier of these shocks i can only suggest that when you tighten the shock up u use a nylock nut that allows some movement on the pivot
i have seen some people using serrated washers and normal nuts to tighten them up which will not allow any movement
when i sell a shock i ask people what rear mudguard they have and what frame and engine as some lugs are longer an need exrtra spacers i then tell them to clean both lugs with emery then apply coppa slip, the bushes should be A PUSH FIT BY HAND you will need to fit spacers to pack the shock from the rear mudguard depending on type the nylock nut should be tightend then backed of slightly to allow some movement of the shock this is how i have done mine with no problems in 4 yrs my half nylocks are just engine mount ones cut in half with a hacksaw and then flattened on some course emery which take less than 10 mins for 2 hope this is of some help
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Fruitjuice
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shocky wrote:just got back from a few weeks away with work then a trip to france . and as a supplier of these shocks i can only suggest that when you tighten the shock up u use a nylock nut that allows some movement on the pivot
i have seen some people using serrated washers and normal nuts to tighten them up which will not allow any movement
when i sell a shock i ask people what rear mudguard they have and what frame and engine as some lugs are longer an need exrtra spacers i then tell them to clean both lugs with emery then apply coppa slip, the bushes should be A PUSH FIT BY HAND you will need to fit spacers to pack the shock from the rear mudguard depending on type the nylock nut should be tightend then backed of slightly to allow some movement of the shock this is how i have done mine with no problems in 4 yrs my half nylocks are just engine mount ones cut in half with a hacksaw and then flattened on some course emery which take less than 10 mins for 2 hope this is of some help
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soullad
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shocky wrote:just got back from a few weeks away with work then a trip to france . and as a supplier of these shocks i can only suggest that when you tighten the shock up u use a nylock nut that allows some movement on the pivot .................................. the nylock nut should be tightend then backed of slightly to allow some movement of the shock ...........
Movement of either the shock or the bushes must surely result in wear ........... and something tells me that in an "engineering" way, this internal slippage within such a component cannot be correct??

Thing is I like the R1 shock, but I think the actual conversion needs to be improved.
Until then Shocky's way might be the best its gonna get BUT suppliers might want to include a spacer to take up any side to side movement caused by the fitting of the smaller spring at least?
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