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Wayward 2003 GPR

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al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Tue Feb 22, 2022 10:39 am

VT78racer - Yea I've not seen this version around yet. And it's a bit complex to try to recreate. Are you doing a full restore?


Weekend work complete. New seals, and dust cap installed in the forks. For reference a 15/16th socket makes a perfect seal installer. I also had to lightly file the top lip of the damper rod to get it to slide through the plastic bushing. I think torquing the top nut so high has a tendency to mushroom it a bit.

As for touring the top nun, it's this tight
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I went with a slightly heavier oil. I think the recommended is 7.5, and I went with 10. Fill to 175cc.
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Started to mock up the new brake, and controls. Kind of okay with the way the reservoir sits.

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Check out Wiring Diagrams for Derbi, Aprilia and More! For some guidance on how to rewire the Domino controller. I picked the controls up from Treats, it's the Domino Buttons 0038AB. Feels like good quality, and as pointed out by ToraTora, it has a dimple on the right side to snugly fit next to the Domino throttle.

Domino Buttons 0038AB


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To make it work for the Derbi I connected the black wire with the Orange wire. So Orange activates when the switch is in the "Run" position. Then you need to swap out the end connector on the Black/White wire. I used some of the left over harness from the original part. I also needed to lengthen the harness from the brake switch, and again used some of the leftover wire.
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User avatar
al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Wed Feb 23, 2022 5:19 am

I HATE PREVIOUS OWNERS! :rage:

With that out of the way. At some point in time a previous owner snapped off one of the bolts for the front disk. It happens a lot with these bikes. Between corrosion and a copious amount of thread lock you have to use heat when removing them. Someone didn't. Not only didn't they, but they covered their tracks by power coating over the shaped bolt. Why?

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It gets worse. After filing it down a bit to get a good surface to work with. It seems the PO did attempt to remove the broken bolt. But snapped off the easy-out. I guess they gave up after that. You can just make out the easy-out in the bottom pic.

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User avatar
jkv357
Posts: 224
Joined: Fri Dec 01, 2017 6:47 am
Location: WI
Replica: '99 GPR EBE-075
x 425
x 116

Re: Wayward 2003 GPR

Post by jkv357 » Wed Feb 23, 2022 6:45 am

al_pritchard wrote:
Wed Feb 23, 2022 5:19 am
I HATE PREVIOUS OWNERS! :rage:
(SNIP)

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That's pretty shady powder coating!

If you know what you are doing, you always mask the mounting areas for the rotors and other critical parts.

Lots of rookies doing powder coating!
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VT78racer
Posts: 6
Joined: Tue Oct 22, 2019 6:27 pm
Location: Kentucky
Replica: 2003 Derbi GPR race bike - CR80 transplant
2000 Derbi GPR race/street
1999 Derbi GPR street
x 2

Re: Wayward 2003 GPR

Post by VT78racer » Wed Feb 23, 2022 1:18 pm

Yes, I am working on a restore similar to yours. Mine started off life as a 2000 with the older body work. I had most of the later generation body available so i'm trying to update to that. I've tried to recreate the side graphics to a vector file in hopes of finding someone to print in vinyl. This may be useful for you as well.
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User avatar
jkv357
Posts: 224
Joined: Fri Dec 01, 2017 6:47 am
Location: WI
Replica: '99 GPR EBE-075
x 425
x 116

Re: Wayward 2003 GPR

Post by jkv357 » Thu Feb 24, 2022 7:43 am

To remove the broken bolt and extractor, I would probably use a small chisel and try to spin it out. Heating around the area will help, and may be required. Even the powder over it is going to hold it back some, and the heat will help with that also. You may mess up the powder, but it has to come out.

You can also cut a slot in it to help give the chisel hold better.
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User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1756
x 1977
Contact:

Broken Drive or Disc Bolts

Post by toratora » Fri Feb 25, 2022 10:39 pm

It's quite a frequent sight to see either the disc bolts, or the sprocket bolts broken on the Derbi. The reason is these are usually locktited in place. You have to heat them before removing them, and it’s important to use proper thread seal on them when you put them back together. I’m pretty sure I've got Information on this in the Reactivation project, or the Red Power.

To remove I use EZ-outs. They are a reverse thread tool. You first drill a hole with a revers left handed drill bit, and then use the reverse threaded tool. It frequently works, but not always. Some time you have to drill out more of the old bolt. But before long you’ll be adept at doing this sort of thing. :paw_prints:
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User avatar
al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Mon Feb 28, 2022 5:28 am

Took a brake from the wheel, and spent some time with the wiring harness. Aside from a couple of dodgy repairs it's not in bad shape. The same can't be said for the relay.

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I'll pick the wheel up later in the week. For now, I needed a win, and the wiring harness got it for me.
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User avatar
al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Fri Mar 04, 2022 11:26 am

Not the easiest, or cheapest things to fined. But here they are, two brand new handle bars. The ones on the bike were bent, one to far to fix. So two new bars were in order.

These came from Andys Motorcycles in the UK, via eBay

Now we can finish the controls this weekend.

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Quick edit to note that although these will for the GPR, technically they are not 100% the same part. They are a bit longer than the original GPR bar.

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User avatar
al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Mon Mar 07, 2022 6:03 am

In edition to getting the controls (mostly) sorted. The weather got warm enough to get the brake calipers painted. I used a 2 part paint, with two coats. Rather happy with how it turned out.

The calipers have been taking a brake fluid bath for the last couple of weeks. What was left of the original paint was easily removed. Then a quick trip to the wire wheal to brush off some corrosion. And a spray down with brake cleaner.

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It's a use it or loos it kind of paint. Once it's mixed you have about 2 hours to work with it. Plenty of time. Mix, let sit for 5 min, and brush on. Second coat 15 minutes later.

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User avatar
al_pritchard
Posts: 46
Joined: Sun Jan 09, 2022 2:15 pm
Location: Atlantic Highlands, NJ
Replica: 2003 Derbi GPR 50cc
x 7
x 60

Re: Wayward 2003 GPR

Post by al_pritchard » Wed Mar 09, 2022 5:44 am

Little things can make all the difference. Like having a Clutch Return Spring. Ordered from Scooter Parts Shop.

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