Castle Sockets for 2010+ GPRs, and 1999-2005 RS50s

[toratora]

What have people done to source castle sockets for adjusting the swing arm on the 99/2005 RS50, the RS4s, and the 2010+ GPRs? Amazon has a number of castle sockets available for affordable prices—however I don’t know the tool size.



Derbi did produce an official product.

MODEL GPR 50 125 2009 DATE SEPT. 2009 CIRCULAR No 255.370

866714 Tool to adjust swing arm nut on the GPR 2009

Dear dealer,

We are pleased to announce you that we extended our range of special tools. We now propose through our spare parts department, a special key to mount the swing arm of the models GPR 50 2T 2009 and GPR 125 4T 4V 2009, under the ref 866714.

This tool is in particular necessary to adjust the nut number 8, ref. 865615, in the spare part scheme that you find below.

Kind regards,
After-Sales Service Nacional Motor S.A.-DERBI

[Rj_666]

I bought this one recently --
https://www.gbmotorcycleproducts.com/in ... ct_id=4887

Works great.

If you need, I'll measure it.

[toratora]

Yeah that would be great. It would be really nice to have something that folks could order here in the States from places like Amazon.

Thanks!

[toratora]

With everything boxed up it’s been a righteous challenge to get anything done. Today I found the calipers, and thought it would be nice to finally measure that 2005 RS50 swing arm castle nut.

The inner dimension is about 24.46mm, and the outer dimension is about 28.57mm. Hopefully that will be sufficient information for sourcing an affordable, workable tool. I probably should have also tried to measure the width of the finders.

[Berkeley]

.

The guys from gbmotorcyles managed to modify their stock one to fit the nut. They sent a new one free of charge!!

Although the socket should have been 3mm overall bigger (so that the teeth were not so thin) It still fitted fine and it came off without any problem.

[toratora]

I’ve been chatting with Luke over at GB Motorcycles about these sockets and nuts. He checked out this page and based on Berkeley’s measurements Luke is having a batch of sockets made for the newer bikes. This is totally awesome news!! Thanks so much Luke!!

Luke is going to let me know when they are ready, and I’ll post a link in this thread when they are available.