shineray

World of motorcycleS

Dogdragons Does:
A couple of modifactions to a Shineray 125

This is just a general guide.
If you are about to do your own maintenance, using these pages,
I take no responsibility if you get things wrong / if parts wear out faster or break!

I will say this before you go and rush out to find smaller rear sprockets for any machine you might own.
I don't think this would have worked for a Honda, Suzuki or similar.
I certainly wouldn't try to do this to my RX1000, maybe a tooth smaller, but we went down by 9 teeth in this machine.

I was asked to make this machine run a little faster.

When I first time I used the mechine I was getting 50mph (according to this speedo) while the rev counter just under the red line, it was almost impossable to make the thing go faster (down hill maybe or with a good tail wind.... or both maybe).

The Sprocket was

The replacement sprocket

I had to open the centre hole by 5mm to let the sprocket sit peoperly on the wheel hub.
I knew it had to be central too. Otherwise the sprocket would wobble when the wheel was turning.

Grinding 2.5mm out all around opens the diameter of the hole by 5mm

The centre hole was perfect, but I still had to drill the four holes for the bolt holes.

Then I used a centrepunch to mark the future holes, making sure that when the holes are drilled the new holes lign up with the threaded holes in the hub. I used a pillar drill to make the holes
Then fitted the sprocket

Finaly I shortened the chain by two full links.

Tested it, now it got 60mph at the same revs.

I then decided to try to modify the main jet too, I'd never tried doing this sort of thing, but I thought I'd try it and if it didn't work, I would have just reverted it back to standard. I dropped the needle circlip down by two notches. It seemed to have worked

Now we get it over the red line both on speedo, and rev counter.