Restoration Derbi GPR 50 R . France project

[toratora]

Hey Rems,

All of the Metrakit stuff I have is the older style. I would like to check out the newer stuff, but so far that’s not been an option. I know a bit about the 2000 edition GPRs, and I’m happy to help you where I can. I didn’t know that Athena bought out Metrakit. Thanks for the update!

Since you are doing a Big Racing Project please post about it. I would be very interested in how that’s going for you, as my exploits with them haven’t been going as well as I had hoped!

It’s awesome that you know those folks, and I don’t see that as pretentious at all. Hey, did you know that you this forum has a built in translator? It’s in the upper right hand corner of the page. It should be able to translate French into English too if you feel more comfortable writing in French. Would be interesting to see how it does.

Thanks for liking what we are doing here. It’s difficult to source this information being so far away from the action. But these are cool bikes, and they need a support system.

[RemS]

Hi

Here are some images of the progress of the reassembly of the motorcycle.

[toratora]

Remi it looks great. You even got the front fender mounted properly! So many people get that wrong and crack the plastic.

How did you get the foot pegs to look brand new? Even the springs look brand new.

Oh, and something you wont see in the manuals, but since you are doing the restoration I’ll share this with you. On the throttle side of the axel there should be two washers between the swing arm and the final outside nut.

[RemS]

Hi toratora

thank you for the compliment.

the foot pegs have been microbilled.
And the spring are new!

I think I bought almost everything that’s still available at Derbi’s for that bike. (I am derbi dealer)
Screw, spring little plastics and more...

However, I don’t understand, where do you tell me there are two washers to install?

reassembly has evolved. I would try to put new images this weekend.

I’m giving up the bigracing engine, I’m going to get rid of it.
I am in the process of Machined new crankcases for a cylinder 70 Metrakit pro race...

Bye

[toratora]

Hey Remi,

If I am feeling well enough tomorrow I’ll take a photo of the washer where it needs to be placed. It has to do with how they made the axel. The threads are very short, and without the second washer it can be difficult to get a proper binding to hold the wheel. I see that you’ve sourced the chrome plates on the swing arm so you may not need the second washer, but I’ll still get that information for you—hopefully tomorrow.

[RemS]

It’s all right, I got it.
Idid the Reflection during the editing.
the threaded diameter and diameter of the centreline shall be reconciled to the outside of the oscillating arm. I’m going to put the axle rear wheel in the lathe ( machine ) and make a chamfer.

I like the detail. Obviously you do too.

[RemS]

here are some pictures of the engine I wanted to mount at the start.
with:
Stage6 cylinder BIGRACING 77
malossi crankshaft RHQ (THE reference!)
valves VFORCE3 (honda CR 85cc)

Crankcases machined and microbilled

if someone is interested, I can sell the crankcases and the cylinder kit (new )

[RemS]

And here is the new engine block for GPR
I have not finished the work of the crankcases.
These pictures give you an idea of ​​the possible enlargement of the intake of the derbi crankcases!!
I recover my malossi crankshaft and my valves VFORCE3 for this engine.
the cylinder kit is an old version. a Metrakit PRO RACE II 70cc cylinder kit

. I will take pictures of the finished casings before closing them again.

[Berkeley]

Hey rems.. why did you not go with the bbbk and stick with the 70 In the end and what would you sell your block for cheers.. berks

[kaldis12]

Pretty nice work overall. If you are interested in buying new Vforce reeds, then the 2Win Vforce reeds have even better performance in low rpm. Overall they are better than the Cr85 reeds. I just ordered them