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73 R75/5 Restoration Let The Games Begin !

80092

Member
Now that the holidays are over it's time to start restoring my /5. I bought the bike for $600 2.5 years ago from one of my patients the second owner. He had the bike since 1974,word has it Malcolm Forbes was the original owner. The bike did not run for about 1 year when I took possession . When I brought the bike home I knew it would not run due to the fuel in the tank resembled dark icetea. So A quick carb rebuild Fluid flush prep and she fired up. The bike ran OK but the clutch splines seemed dry,this prompted me to lay the bike up until I was ready to redo the bike.
Details to follow regarding step by step restoration. I plan to retain the original paint of the frame and fuel tank, fenders. I will redo the bright work etc

Pre teardown.








Inspection details to follow
 

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Please share EVERYTHING.

My '72 75/5 restoration is not going well as somebody tried to restore it once/twice/thrice before. Everything you post will be sincerely appreciated.
 
My '72 75/5 restoration is not going well as somebody tried to restore it once/twice/thrice before. Everything you post will be sincerely appreciated.
Sorry to here that, Let me know if I can help. The ultimate resto I saw was by Brook Reams, you can see it in the resto thread.
Here is a picture of my bike without the seat,side panels and headlight bezel/lens.Prior owner had a Vetter faring in place,that big klunker is not for me.
 

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Here is a Grey matter teaser , Why would someone stick a wrench under the foot peg ?
 

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Wrench under the footpeg? Looks like the brake lever travels farther than it should and the wrench was put there (probably temporarily) to keep it from hitting/riding on the underside of the footpeg.
 
Wrench under the footpeg? Looks like the brake lever travels farther than it should and the wrench was put there (probably temporarily) to keep it from hitting/riding on the underside of the footpeg.
Kurt good suggestion but not correct. Another clue, the wrench under the foot peg serves a purpose when performing a special test.:)
 
Argh! I can't stand it!! OK, while balancing the carbs, if the wrench vibrates out and hits the floor, that's an indication the carbs aren't balanced? :whistle
 
/5's are a favorite of mine. Looking forward to following your build. You will need patience, perserverence, fortitude, and a lot more of stuff like that. Oh, and probably a lot of cash. I'm in the middle of a similar project, so I kinda know. A '74 is somwhat similar to the longframe '73. Good luck with your project. :thumb
 
Argh! I can't stand it!! OK, while balancing the carbs, if the wrench vibrates out and hits the floor, that's an indication the carbs aren't balanced? :whistle

Too Funny !

Leakdown Test... With the bike in gear and drive line slack removed I use a wrench to lock the rear break. This will help keep the piston @ OT under high pressure and not allow the crank to rotate.

I mention this because part of the /5 Health analysis was to check the valves and rings for wear with a Hot and Cold leak down test. My bike only had 4 % loss of pressure bilaterally. Pressure loss was noted in the crankcase when removing the dipstick,the 4% in the cylinder was passing the piston rings .
 
Nice toaster project Pete:thumb

I also have a ' 73 /5 currently on a lift and s-l-o-w-l-y making progress. I already had too many projects in the shop when this one got rescued.

Enjoy and share....as mentioned Brook's thread has a lot of great info...and pictures:thumb
 
Project Update

The teardown objective for this segment is to get the Transmission and clutch removed. Detailed inspection will follow after the bike is disassembled into it's component parts.
I followed this order of part's removal. Rear Wheel , Final Drive, Rear Shocks, Measure swing arm clearance and record , Remove front clamp for driveshaft boot, Remove Driveshaft bolt's and washers ( Special Tool ), Loosen Swing arm Locknut R & L (27 mm Tapered Socket Special Tool ), Remove pivot pin and locknut as unit, Withdraw Swing arm, Disconnect neutral wire on back of trans , Air box with choke mechanism , Clutch cable , Clutch control arm, Transmission case bolts, withdraw trans from left side.
Some Pictures.
 

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Swing Arm Special Tools

The swing arm removal was made easy with some special tools from Cycle Works. The 27mm tapered socket and drive shaft bolt tool made removal easy. Post a picture later.
My swing arm clearance was not equal as it should be. Right side- .203", Left side.196".
 
0.007'' out of alignment. It's a wonder the bike could even approach rollin in anything considered a straight line. :laugh
 
0.007'' out of alignment. It's a wonder the bike could even approach rollin in anything considered a straight line. :laugh

Yeah not much of a difference, measurement was taken @ 3 o'clock on the R and 9 on the left. The measurements at 12 o'clock had more of a discrepancy ,bearings were notchy and will be replaced.
 
Special Tools

The 2 special tools used for swing arm removal. On the left is for the driveshaft bolts. The tapered socket on the right is for the swing arm lock nuts.
 

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Clutch pack Removal

At this point we have to pull the clutch pack. The key is to progressively loosen all the bolts a bit at a time. Splines on the input shaft of the trans were dry as a bone. Appears to be the original clutch thickness .1890 minimum spec is.1024. Did not have much life remaining.
 

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FD Splines / Axel

Here is a dirty shot of FD splines and rear axel swing arm crud before removal. Any comment's regarding spline condition ? Not the best pictures.
 

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Aren't digital cameras fun! :stick Would need to see clearer pictures of the final drive side...to see if there's a ridge forming close to the hub.

You mentioned on the clutch pack removal that you progressive loosened each screw a little at a time. Typically the way to do that is to remove every other screw and insert a long bolt with washers and nuts hand tight down to the back of the pack. Then remove the other three screws. Finally, progressively back off the three nuts to let down the pressure of the clutch spring.
 
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