My RI Shock snapped tonight

[byron]

just got to find a solution

yep, certainly have.
I've done over 7500 miles on mine, I looked at it following soullad's post and seemed fine, but I am a little concerned.
[to save me taking mine off] what is the id of the R1 eye ?
there must be something that fits...
there's a good rubber wholesaler in norwich, they always seem to be able to find exactly what i go in for, so will see if they can help.
anyone tried the ones stokie posted on the other thread ?

[guygrrr]

in original spec one side of the R1 shock is mounted solid and the other is mounted on needle bearings and a race.
i had thought about trying to find bearings to fit, but hadn't bothered.

lloydy came up with a steel sleeve slightly longer than the bushing that the nut tightens against.

http://www.smellofdeath.com/lloydy/imag ... ushes3.jpg

[soulsurfer]

Is the common thing with the three reported breakages with brass bushes? Who supplied/made these bushes and how tight did they fit to the shock eyes? Have any fitted with the nylon/ PTFE bushes failed as I can see more room for movement with these?

[Rich_T]

You might want to consider that this metal fatigue failure is not down to the mounting bushes but actually more to do with the engine mountings.

The Lambretta engine rotates not only around the engine mount bar but also side to side as the engine twists over uneven surfaces and during acceleration and breaking. This side to side movement is not taken up in the solid R1 mountings and therefore stresses the metal, essentially it is the shock that is attempting to hold the engine straight. The R1 shock never had to deal with side ways movement because the swing arms all run in bearing, nice an colinear, not exactly like a Lambretta.

The only way you'll get round this is to either 1. make an elastic rubber bush for both ends of the R1 shock or 2. work out some rose joint system if someone sends me the the internal dimensions of the shock mounting (ID and length) I could sketch something up on CAD and post it up for a rose joint solution.

The other option is solid engine mounts, and have your teeth rattled out (not really a good look).

[coaster]

I don't have an R1 shock but have been reading both threads on this topic with interest. Has anyone taken Rich up on his offer to explore the rose joit route? seems like some good lateral thinking.

[soulsurfer]

I've posted the measurements elsewhere, but to be honest, I'm not sure how it can be done as the boss dia is so small the wall thickness is only 3mm at the top and 2mm at the bottom, so don't raise any hopes.

[rbgaz]

sorry to butt in here but ive just put a bgm new shock on my gp and it was a pig to get on really tight had to help it on with a hammer an socket were as my taffspeed one just gos on an off with ease should i be worried ?

[andylaw7]

yes when youre trying to get it off ?

[teamv]

David, following on from your experience and the other stories here:http://scooterotica.org/forum/viewtopic.php?f=7&t=3547

Mine is coming off and being replaced with an Escorts standard jobby before i ride it again

i wouldn't bother ,bought this at the shed weekend ,only got 60 mile ,was on the m6 about j4

the dealer was quite helpfull and refunded the money ,but still left me with the aa for 9 hours.; :flaming:

[Knowledge]

Here's a thought on how to check any shock for correct fitting.

Support the back of the scooter with a block of wood under the number plate and remove the shock. Refit the shock at the top only and tighten the nut as usual. Now try rotatng the shock around this pivot point. It must rotate by at least 10degrees, but it must move relatively easy to do. You might need to back-off the nut in order to achieve this movement, or apply some suitable lubricant.

Now remove the shock, and refit to just the lower mount. Again, check for at least 10 degrees of easy movement and back off the nut is necessary.

Now remove and refit the shock at both ends, and fit the nuts as per your experiment. After this, you have proved that the shock can rotate as part of it's operation.

That's not a bad approach, is it? I think Nylocs would be wise.

Martin