Another '74 400 CR Build

Returning member. I purged all my garage "collection" when I moved to Monterey, California, but couldn't stay away. Drove 6+ hours yesterday to pick up a '74 CR 400. Was a former AHRMA race bike (8 years ago) supposedly restored by Bill West.

The good:

• Nice condition Magnum pipe (very cool looking)
• frame appears power coated
• wheels rebuilt w/ stainless spokes
• aftermarket pegs
• works performance rear shocks (w/ what looks like zero chain clearance)
• zero rust in tank
• so far cylinder / motoplat / clutch look pretty good

The bad:

• tank rear bolt tab is gone. Will have to either not use or have a band hold down welded in place
• set up w/ 38mm Mikuni (what?). No airbox rubber interface just silcone (see below)
• more silicone sealer than I've ever seen
• seat / foam needs help
• no Bufo hardware. More local hardware store bolts / nuts than I've ever seen (any stainless bolt sources out there?)

This won't be a resto in the likes of Picklito or Retro Rocket. Just need to get my ass out there at an AHRMA race before I can't!
Rick

That's a nice looking bike. I like the Mikuni, Works Performance shocks, aftermarket pegs, and that pipe has to be a performance improvement. I thought the 74 CR came with the plastic air cleaner housing. Maybe someone changed it.

I had a Mikuni on my 73 450 many moons ago and it only had 2 O-rings to seal the connection to the airbox. The carb had grooves cut into the outside of the intake bell. The set up worked well.

Amen brother! Same here! That's a good motivator.

Slowly going thru it. Appears that it was raced and enjoyed, but not really maintained. Hardware store zinc bolts are rusted. Rear brake lining rusted as well, so guessing it was powerwashed after the race and stored. Most of the bolts are loose, with exception of the swingarm bolt which was too tight and binding the arm. Any tips on this bolt (i.e. safety wire or cotter pin) so as to allow it to be loose enough to give the arm full travel? Does anyone know if Chuck is still selling some of his billet products at Husky Junk? would be nice to pick up his brake arm and pedal

The torque for the swingarm bolt on the MK frame is 26 ft. lbs. Sounds like yours may be to tight. Since the rubber swingarm bushing is all that allows for swingarm movement its also possible the inner steel spacer is narrower than it should be causing the swingarm knuckle to bind on the frame. Your guess is as good as mine why the swingarm doesn't move much.

I've never heard of there being a problem with your early swingarm coming loose when torqued to 26 lbs but apparently there was a problem with the later ML GP frame as Husky sent out a service bulletin in 1975 calling for the 75 swingarm, with the same bushing setup as the MK frame, to be tighten to 50 ft. lbs.! Go Figure.

Years ago I emailed Husky Junk about parts and he responded that he was no longer selling stuff.

FYI, PVP Cycles carries some stock of Husky Junk parts. I was able to order his swingarm bearing conversion kit from them. Also found some hard-to-find small parts like clutch locking tabs.

Anyone know a source for the piston spacer 16-10-921-01 ? I messed one up removing the piston pin. Also, what's the best way to clean the barrel & head of old dirt & drool? Not planning on blasting / painting, just want to make them more presentable.

make a mix of kero and detergent and scrub vigorously, get some small bottle brushes, wire brushes etc to get in btw the fins ...this will removes the majority of oil and crud...then get a serious truck wash and spray on a 30% mix and leave to soak for 10 - 20 mins brushing regularly..this should remove the mud stain that usually wont come off...wash with plenty of water as this stuff is an alkali....should be right to paint following final clean with a thinners etc. don't forget to dry carefully after each step and lightly oil the bore to prevent rusting.

Got my swingarm reinstalled after removing rubber bushings and replacing w/ Andy's needle bearings. Tomorrow I'm moving it up to Tahoe area (new home!) where I hope I can finish it up and try an AHRMA race or two! Can't wait to hear it run again