1991 CR250R Project Bike Build

Maxx MRP

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#1
I adore the USA since I was born, but I'm French so please excuse me for my language, I translate with Google.

That's it I find an old CR 250 as in my youth, those who have friends on facebook have already seen some pictures.
the time to reduce the size of the photos, I would start posting here with comments.
see you soon for more

It goes from there

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Maxx MRP

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#3
Thank you
so I got the bike in early August and I went a little bit on the job. I will post the photos and comments until the stage where I am today.
I am still very far from the final reconstruction.
 

Maxx MRP

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#4
For suspensions, original it's really not good, ok at the time we drive with, but we're more at the time and with the evolution that have known the suspensions, I can not see myself go back , this fork is not even adjustable in rebound and rear shock not adjustable in hi-compression.
so for the front, I will adapt the fork (either the original KYB PSF 1 or the spring KYB that I mount on my 450 CRF 2013) triple clapms, the front wheel, the braking assembly and the wheel axle.
for the back I will try to find for cheap, an original damper of 250 cr - crf / 450 crf until 2008 and of course it all go into the magic cauldron of MRP to personalize all that according to what I I appreciate and need.
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Maxx MRP

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#6
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very big problem.
the screw is locked in and I can not separate the two parts, I remove the screws from the inside and spraying with oil of sting and I also heat, it does not move a milimeter

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Maxx MRP

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#7
and we attack the opening of the engine
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surprise by depositing the valve box, the cylinder has been prepared (well we'll see later) and for the moment I'm going to mount only the reeds Boyesen (which I have always done on all my 2 times since the beginning, the change is drastic) and then once the restore is finished and I have a little more side, I would mount a Rad Valve.

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not rust on the stator

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the part that made me very scared considering the number of years that the bike did not ride, it's like new.

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Maxx MRP

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#8
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I wondered what it was like to be a rag.

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It's okay


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not too bad considering the age of the machine

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we return to it, ported but half, no retouched transfers (diagrames) and no cases notigned either, but hey it is neccessary on a 250 ?? although in 88 on the mine I made the total.

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Maxx MRP

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#9
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Have you ever seen a crankshaft seal in such condition? that explains the ton of black fat on the engine and the frame.

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therefore wear of the ring and therefore replacement

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So there sensitive souls abstain, we will proceed to the separation of two casings, the tools of torture are ready

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Maxx MRP

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#10
and in the end the bearings are ok, they have been changed in the course of life of the bike, but I will still replace everything as it is open.


the box is ok, no broken teeth or other suspicious marks, me happy

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Maxx MRP

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#11
here is the rest of the work on the swingarm.
I found myself with the screw of the tension adjustment of the chain of transmission, twisted and blocked by the rust.
Seeing that this part of the swingarm seems to be in 2 separate parts (actually there are three), I decided to get out all to have more ease to deal with the screw in question.

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We see that on the 2 photos below, a kind of epoxy glue.

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Maxx MRP

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#12
to try to spread, to get out the part where there is the thread.
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and after a lot of liters of perspiration, I managed to separate everything, I understand why it was so difficult

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Maxx MRP

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#15
Work on the pipe
So the denting of the pot with compressed air went well, except that at a time -----> air leakage and there I realize that there are cracks where they welded nuts (messed up) to install a protection (carbon, aluminum ... I do not know) so it was necessary to close by welding as I could because I do not know what were soldered nuts, but it m made fireworks, so not simple and the sheet is fine.


I decide anyway to turn these nuts, which took me in the morning, a sanding stroke to see more clearly below the rust and try to remove the solder and solder patches.
Only I can not get rid of these cracks, I weld for the eliminated but once cool I see another that is created next and sanding I see others!
So do you have an idea for me to be, or you know a specialist (can be a cauldron, I do not know) who could redo the two parts of the pot elbow, just cut or it is crack and redo with the sheet intact, if there are welds in + it will be more beautiful, too bad for the original appearance of the Pro Circuit can not be found, if it can save the pot.


I also did a test of blueing on a sanded part to see if I could redo it on the welds as at the origin, it's good it works and it's beautiful

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