My overseas ’84 480R build

[rayatc84]

When I joined the site, I wrote that since I have read the Bigbore thread about the 480R conversion, I have been dreaming about a 2nd gen 480 conversion.

Everything has started with these:
http://www.3wheelerworld.com/showthr...highlight=480R

http://www.3wheelerworld.com/showthr...highlight=480R

The ‘82 finished is here: http://s.com/?p=926


But I immediately preferred make the build with a 2nd gen because I believe the chassis/suspension is better.

After several hours of search here, on 3WO and AF.com, I have only seen these about 2nd gen 480R:
http://www.3wheeler.org/vb/showthrea...highlight=480R

http://www.3wheeler.org/vb/showthrea...highlight=480R

http://www.3wheelerworld.com/showthr...?highlight=480

But unfortunately the rare pics on these threads are too small to see details on biggest issues of the build:
• Engine mounts: specific mounts to make the 480 engine fit the 250R frame,
• Kick starter: modifications to make the kick starter clear the R frame,
• Exhaust pipe: modifications of the CR 480 pipe to fit the R frame,
• Gear shifter lever: modifications to make the shifter lever clear the R frame.

So any help, info and above all pics would be very much appreciate! Please don’t hesitate to post here if you have any.


After several months/years of search, I found a ’83 480 CR engine (with 5 speed gear box, the ’82 have only 4) in 2010 spring, and in the last couple of month a cheap complete ’84 250R.

So now I can start the build. I’m afraid it will be a long build because I will not really have much time for him.

My objective is to not make any modification on the frame: no drilling nor cutting, nor welding, nor grinding. Only bolt-on mounts.
I would want at the end of the build that the frame could receive interchangeably the 480 or original 250 engines.

I started by taking measurements of the 250R front sprocket position.
After that, I put the 250R engine out of the frame and put the 480R engine with its rear mount on the frame.

The lower motor mount and the rear 480 CR mount lined up perfectly and the swingarm bolt went through without a problem.
With these 2 mounts bolted the sprockets lined up perfectly, in the same position than the 250R engine. The engine just has to be stalled laterally!

The rear mount will be a mix between 250R and 480 CR mounts.

I am at this stage: take measurements and design the rear mount.

Okay, enough blabla, now pics!

The ’84 250R when I bought it:


These 2 engines have to be able to be bolted on the 250R frame…







480 engine put on the 250R frame:







The 480 just fits in the 250R frame!





Rear mount side view:

[rayatc84]

The bases of future rear mount:







Lower mount side view:





Front mount side view (has to be designed…):





This head will have to be fixed on the frame …



The kick starter issue: it immediately blocks to the frame…

[rayatc84]

Today I have worked a couple of hours on the project.

I started building a cardboard model of the rear mount.

It fit without a problem and all the axles/bolts went through perfect.

Here the pics:












I also looked the shifter lever issue.
I put the ’84 250R shifter lever on the 480, and it fit perfect!





The only small problem is that it is a little short.
The 9,5 cm measurement on the pic below is approx. 13 cm on my other 250R (’82, ’85 and ’86) and approx. 12 cm on my GasGas enduro bike.
So I will have to extend 3,5 cm the shifter lever, but it should not be a big issue…

[wolfspider]

nice work you are doing there, where abouts in france are you??
steve

[jeddy]

This is good to see. Please keep posting pictures as it progresses. I'd be pretty interested to see what you end up with for a pipe and also the intake tract.

Thanks
-Jed

[JasonB]

Great thread, nice details! Loving the pictures, in for updates

[sx250heath]

Sweet build. I can't wait to see how it turns out

[rayatc84]

Some update.

I’ve completely designed all the engine mounts and I made plans on computer. But unfortunately I don’t have the equipements/machines to build what I designed.
So I sent my plans in Switzerland to my buddy Pote, akka “pote swiss” on the board and he built the mounts according to my plans and then sent me a package with all the mounts!

I assembled the engine/frame/mounts: everything lined up perfectly and the axles/bolts went through without a problem.
So I'm pretty happy with this result, because Pote is 500 km from me and he built the mount only with the plans and some explanation by email; he didn’t have the frame nor the engine to make intermediary verifications during the build and finally there is no bad surprise.

Here are the pics:

Rear and front mounts parts after laser cutting and bending, and before welding:




Rear mount:




Front mount:




Head mount:






Rear mount on the trike:








Front mount on the trike:








Head mount on the trike:







Lower motor mount:




Next steps will be the exhaust and the kickstarter; I think they will be more difficult…

[Jason125m]

Wicked! Very interesting build. Those mounts came out real nice. Great work so far.

Keep it up.

Jason

[Keith Salyer]

Very nice work, I think you are right the pipe and kicker will be a challenge

[ScreaminRed]

Wonder what is happening with this? It was very interesting and the last post was almost two months ago.

[rayatc84]

Wonder what is happening with this? It was very interesting and the last post was almost two months ago.

Nothing else at the moment... Unfortunately I haven't had time to work on this project and make any progress...

[rayatc84]

It has been a long time since I have posted some update…

I’ve completely designed the kickstarter extension and I made plans on computer.

But unfortunately I can’t figure how to measure the splines on the kick shaft and define their odds. So I had to disassemble the shaft out of the engine; with my plans, the shaft and the kickstarter, a buddy of mine has built the parts.

I'm pretty happy with the result, but I can’t test it at the moment because the engine is completely disassembled. I hope I haven’t made mistake when I made the plans…
In fact, when I disassembled the kick shaft out of the engine, I decided to disassemble completely the engine to verify it. The result is: bore honing, new +0.75 PROX piston, crankshaft bearings; all oil seals and gaskets.

My buddy Mathieu, akka “Way²” on the board, has sandblasted the cylinder, head, crankcases and clutch case.
Now I have still to paint them.

Can’t wait to test the kick extension with the engine in the frame, but I will have to be patient…

Here are the pics:

[250rmanfmf]

I love this build, I would love to build a 2nd gen 250r with a 480r in it. Maybe one day. Keep up the great work.

[rayatc84]

Another long time without update…

Here are the too small evolutions since my last post:














I have put the engine in the frame + the kick extension and it seems to be ok.
I have a complete 480CR DG pipe+silencer and have found someone to adapt it to this build. I hope to have it made in a couple of months…
So for the moment the trike is taking dust, temporarily and partially assembled, just to allow the exhaust build.