1974 Honda CL360 barn find

Looking good, Jonathan. You'll be terrorizing the neighborhood in no time!

I've still got that 360 cylinder if you need/want it.
 
I spent most of the first half of this year helping my dad die with Alzheimers, so the projects have been on hold. I'm caught up enough now to have some time for hobbies, so I'm digging into the engine. I'm getting the cylinder block ready for boring (for GS850 pistons), and I'm having a terrible time getting the fiber gasket off the bottom of the cylinder block. Any suggestions? I've soaked it in parts wash and hit it with the propane torch. I have to dig so hard with a razor that I'm unintentionally shaving aluminum.

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Sorry to hear about your dad, Jonathan. Went through that w/ my mother. It's good to see you back.
 
Thanks. That is exactly how I would describe his last 4 months. We were all relieved when the trial was over.
My dad is in final stage liver cancer and everyday he is not in a hospital bed is a blessing. He had a turn a couple weeks ago and we thought he was done, then the old stubborn fella pulled out of it and went home and has been doing well again so we think we have a few more months. It still sucks but he made it to 80 with pretty good health before this happened 8 months ago.
 
My dad is in final stage liver cancer and everyday he is not in a hospital bed is a blessing. He had a turn a couple weeks ago and we thought he was done, then the old stubborn fella pulled out of it and went home and has been doing well again so we think we have a few more months. It still sucks but he made it to 80 with pretty good health before this happened 8 months ago.
Sorry. It is hard to watch and difficult to let go. My dad died in May. August 1 would have been his 80th.
 
After a week of soaking the combustion chambers is carb dip (draining them every day and scraping at the carbon with a plastic knife) I finally got them clean. Ii think this engine was running poorly when the bike was parked for good 30-40 years ago.

The GS850 pistons have a true dome profile whereas the Honda pistons have a flat top dome. Also the compression height of the GS850 measures a little taller. So I am going to take some specific measurements to verify dynamic compression ratio, squish, and valve clearance. Ideally they zero-deck, bit I might need to do a custom head gasket to hit .040 squish.

I think the most significant performance gain from the GS850 pistons is the increased compression ratio rather than the increased displacement.

Does anyone know the combustion chamber volume? (I will probably just measure it myself with liquid to get it spot on.)

Also, what plugs / heat range are guys running after the GS850 mod?

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After I measure the combustion chambers with the plug I'm running, I will disassemble the head and glass bead blast it. Then I will lap the valves/seats and reassemble with new seals (guides look good).
 
So... evidently Airtech Streamlining is defunct. Doh! That was my plan for a full race fairing. Anyone know of a backup option? Maybe Motoforza, but they ain't cheap.
 
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Also, I found a thread here from 2012 about modifying the oiling on the 360 motor, but all of the pictures are gone. Does anyone have a link to a splainer on the process?
 
That's good news. Makes sense, too, since they made the windscreens.
Got the fairing and windshield ordered today. Prices went up a LOT after Gustafsson took over. I had budgeted about $550 for the fairing and windshield, but it ended up being just under $800 (shipping was $80). They were accommodating by throwing in a couple sets of L-brackets, painting the inside of the fairing primer grey, and drilling and fitting the windshield. They also discounted 3% for paying by check. Lead time is 7 weeks, so maybe I'll have it the first week of November.

I got the AJSM7 3-piece fairing and clear low-profile windshield. Not an exact match, but closest option to match the RC174 with a headlight opening.

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Almost done rebuilding the starter. Painted the body black and bead blasted the end caps. New stainless screws. Waiting on a new ball bearing to come in the mail so I can finish reassembly and test it out.

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Head is prepped and ready for bead blasting. Hope to get that done tonight.

For new plugs I decided to go with NGK iridium plugs one heat range cooler due to the higher compression of the GS850 piston domes. I'm using the original plugs to plug the holes for bead blasting.

The cylinder block has been delivered to Chris Thomas of Mototech USA in Mansfield, Ohio, for boring and piston fitment. What a guy! Super easy to talk to, fair pricing, and fast turn around. He got it yesterday and said he will ship it out tomorrow. Highly recommend him for machining services.

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