Gear shifter support bush

[neily03]

Hi all,

I've got a Scooter Restorations gear shifter - http://www.scooterrestorations.com/lamb ... r-support/

The trouble i'm having is getting the support bush to fit inside it as either the bush is too large or whats probably the problem is the internal diameter of the shifter is way too small for the bush. It fits fine without the bush but does feel like a good idea to use it without.

The bush is No 1 on this drawing - http://www.scooterrestorations.com/lamb ... eedometer/

Any thoughts?

cheers

[Warkton Tornado No.1]

The problem with remanufactured components from so many sources is that there is no overall QC (Quality Control) to ensure that any part, wherever manufactured, will fit & function as it should, mated to any part that it should fit, again, wherever it was manufactured.

However, the fact that the gear shifter fits on the 'bar without the bush means that it must be 'nearly right' so, as that is the most difficult to modify, it would be best to modify the bush. That said, I would suggest that before you do anything else, if you can wrap some very fine abrasive (wet & dry will do) around the left bar with a contact adhesive & fit the gear shifter to polish up the inside, it would do no harm.

Then, it is a case of reducing the bush diameter gradually until you can achieve a running fit. How you go about that is up to you, but I would fit it concentrically on the plain shank of a good fitting countersink screw with a washer & a nyloc type nut to clamp. (The countersink will virtually ensure that it is concentric) You can then spin it up in a (preferably pillar) drill with a fine file (or abrasive cloth on a file) to reduce the diameter, which should remain bigger than the 'bar that it will be pressed into.

Nylon is not the easiest material to machine, as it can so easily get hot & melt, which is one reason that cutting tools need to be sharp. If you have a high speed cutter such as a die grinder or Dremel, that may be better than a file (whilst spinning the bush in a drill), but go steady!

With care, you should be able to achieve a smooth gear change action.

[neily03]

Great thanks for the advice. While the shifter fits fine without the bush I think it needs quite a lot taking off to get it to fit. I've gone through two nylon ones trying to file them down with no success so I've ordered an brass one from MB and will take it into work and turn it down on the lathe.

It's really frustrating how badly some parts fit....