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Discussion Starter #1
I am starting a new thread to update you all on my progress. I had a few posts on the introduction page. If you saw it you will remember that I found this at the abandoned farm place of the original owner. He parked it in 1981 and never touched it again. I stumbled upon it and wanted to buy it to get it on the road again. He ended up just giving it to me. The engine turned over fine and the bike was 100% complete. All cables, carbs, rear brakes were all froze up.
 

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I power washed and cleaned everything before doing any disassembly. I also wanted to lube up the top end and inspect before turning it over too much. I removed the valve covers and pumped oil into the journals via the holes in the cam lobes. Once I had everything lubed, I spun it over a few times and inspected. I set the cam chain and adjusted the valves. I noticed the LH exhaust cam lobe is scored and the follower is worn. The min gap I can achieve is .005". This will have to be reworked at some point. I timed it and reassembled. After an oil change, a quick carb cleaning, and oil filter cleaning. I started it up. Ran pretty good for sitting so long. I checked the compression and have 165 on both cylinders cold. I think this is pretty good considering how long it sat. I am sure it will improve some after running.
 

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Great find, glad to see another one saved.
 

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Discussion Starter #4 (Edited)
I have been going through everything. I have all of the electrical back to normal (thanks mice). I am currently rebuilding the carbs. It was idling at 2000rpm. And would only go down to 1000 if I choked it a little. A trickle of carb cleaner around the outside throttle shafts and intake books would nearly kill the engine. These vacuum leaks need addressed. I am awaiting new throttle shaft seals so I can reassemble. (25 bucks for 4 small felt washers?!, I feel violated).

I disassembled the hubs and took off the old tires. The rear brakes were froze. So bad, the brake shoe material stayed with the wheel when I took the housing off. I have new rear shoes on the way. The front brakes were fine. I cleaned and adjusted them. I got the front brake cable free and working nicely. I will replace it soon to be safe. The rims cleaned up pretty good! My tires arrived yesterday, looks nice with new rubber.

On the way: AGM battery, fork seals, fork boots, new drive chain, petcock rebuild kit.

Not looking forward to cleaning up the rusty tank.
 

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Discussion Starter #5
A crazy lead on a parts bike a couple weeks ago resulted in an identical 1971 CL450 with a title for $400. (in background) Too good to butcher. Now I have twins! I did use the exhaust as my other was FUBAR.

Sorry honey, a little less space in the garage now.
 

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I noticed the LH exhaust cam lobe is scored and the follower is worn. The min gap I can achieve is .005".
I don't know how much experience you've had with these engines, but the left exhaust lobe and follower are the last to get oil during warmup and hurrying away from a cold start repeatedly can do that even if all else is working properly. The exhaust lobes and followers run hotter, of course, and this also contributes to their accelerated wear, but giving the engine at least 1.5 to 2 minutes of idle-speed warmup time before putting the engine under any real load goes a long way to preserving the parts... as you already know from seeing inside the valve covers, there is no oil retained under any of the parts - and it was a great idea for you to pump the cams full before starting it for the first time in a long time. Something else you should know... be sure to turn off the petcock every single time you stop somewhere, no matter for how long, as these carbs are prone to "weeping" a bit at the float needles and if the fuel is left on it can drizzle into the top end through an open intake valve, past the rings and into the bottom end, diluting thew oil and causing more damage when run that way. Delta Cams can refinish your cam and follower inexpensively once you're ready to do the repair
 

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Discussion Starter #7
Thanks for the info. This is my first 450 but I did lots of research and did read about the exhaust cam issues. Is there a way to improve oiling to these parts? Or is it not neccessary if the engine oil is good, and the proper warm up is done?
 

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I wouldn't say it isn't necessary... any improvement in oiling or oil retention for the exhaust cam couldn't hurt, but if treated properly and maintained well the engine suffers little excess wear there. Here's something you can do that is cheap and can't hurt, and there are a couple other things too that require more detail

https://www.hondatwins.net/forums/1-project-logs/65305-cl450-project-reboot-street-legal-time-7.html#post693025

https://www.hondatwins.net/forums/1-project-logs/65305-cl450-project-reboot-street-legal-time-7.html#post695345

the second link shows how you can make a crude oil "return" out of an extra baffle plate from an intake valve cover to help direct oil back at the exhaust cam lobes at higher rpm, something I learned from Terry Naughtin of Team Hansen road racing
 

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Discussion Starter #9
Well, I took it for a ride for the 1st time the other day. Ran OK, was starved of fuel. Turns out my petcock 4 position seal from my cheap rebuild kit ripped apart and plugged a passage. This is strange. I am very familiar with these and even greased the parts when assembling. I got it put back together but it trickles when "off". I will need another.

I also am chasing a high idle issue. Valves, cam chain, timing all set. carbs synced, play in the cables. etc. I finally looked at the advance ant the spring ends were worn into the weights creating some slop. I carefully closed the ends to take the play out. I retimed it and rode it again. It helped a lot. Still a little off on idle and it seems to run rich. I am now thinking that I have my throttle plate in wrong. There is a small machined relief on one side and I think it is in the wrong position. I have it on the top. I posted on the 450 side of the forum for input.

I had never rode a 450 before, lots of power! what a blast! I cant wait until I get it finely tuned.
 

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You're on your way to great, iconic old bike with a load of priceless patina for next to nothing. You did it right my friend.
 

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Discussion Starter #11 (Edited)
Well my point gap was messed up, causing my timing to be advanced at idle. I didn't time it with the timing light at first. It runs a lot better now. It still has a high idle (2500) and if it drifts down to a thousand RPM it'll slowly die. I took it for a 10 mile run and drove it by the gentleman's house that bought it brand new. He happened to be sitting on the porch when I drove by so I stopped. He was amazed that I actually got it running. He was thrilled to see it back on the road! I had him pose for a picture.
 

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Well my point gap was messed up, causing my timing to be advanced at idle. I didn't time it with the timing light at first. It runs a lot better now. It still has a high idle (2500) and if it drifts down to a thousand RPM it'll slowly die. I took it for a 10 mile run and drove it by the gentleman's house that bought it brand new. He happened to be sitting on the porch when I drove by so I stopped. He was amazed that I actually got it running. He was thrilled to see it back on the road! I had him pose for a picture.
Nice bike. Your throttle shaft seals might be causing your idle problem. I put new seals in my 450 and it got better. What it took to fix it was oiling the seals. I used liquid wrench white lithium aerosol. Remove and seperate the carbs, tape the head end to a shop vacuum with duct tape, turn the vacuum on, place your hand on the choke end and spray the seal areas with the liquid wrench. It should draw the oil into the carb venturi. You will be rewarded with a very smooth throttle action and the bike will idle correctly. Felt seals are intended to be oiled. This is part of my annual maintenance.
 

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Discussion Starter #13
Thanks for the advice, I will try that!


I have an engine question for you gurus. I have a nice used exhaust cam and followers that I would like to put in this engine. I plan on riding this bike for the season and starting the restoration in the winter.

Is there any issue with splitting the cam chain (oem, 8500 miles, no other splits) and replacing the galled exhaust cam and followers with the head still on, in the frame, and reveting a new link on? I have a follower that is heavily worn (I estimate it could have a divot as much as .040") from a prior oil issue. I hate running it like this as I do not want any more metal to get in the system.


Also on a side note, I was wondering if the head can be removed with the engine in the frame?
 

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I know the head cannot be removed with the engine in the frame. I have never removed a cam with the engine in the frame. It is awkward enough the get the followers on with the head off of the engine. It might be possible, but I have never done it. It is not that bad to pull the engine. Here is a time lapse video where I changed the cylinder base gasket during a 3 day weekend:

 

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It can be done, but it requires significantly more patience than if the engine is on the bench. The biggest hurdle is not the disassembly, but the re-assembly - since the intake cam is the one that has to be levered into position (it won't sit on the timing mark as it is just beginning to open an intake valve and will spring back), you have to work the cam chain ends around to the back of the engine after properly positioning the exhaust cam (with both pistons in the middle of their respective strokes to avoid valve contact while rotating the exhaust cam) to get the chain in position to hold the upper run on the intake cam once it is levered into the timing mark, then lift the end coming from the crankshaft up to the intake cam sprocket and put the master link in, then either press the side plate on or stake the pins (depending on which master link you get with the chain if you replace it, or which master your existing chain uses). I've done it in the frame twice on my build (oil flow issues early causing damage) but only removed the exhaust cam, but you could easily do both cams and followers as well. You just have to properly position everything so there is no tension on either camshaft when removing the bearing caps to avoid damage to them. If your frame paint is factory or in average condition, it might behoove you to pull the engine - especially if this is the first time you've worked on a DOHC 450. I did it because I spent money on powdercoat and did not want to damage it taking a 165 lb engine out of the frame and back in again
 
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