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Discussion Starter · #1 ·
This past weekend I took my 71 CB450 on its first ride in over 42 years. The bike has 5K miles on it and sat by the previous owner because of a driveability issue. The problems he had I'm assuming I fixed. I found loose wire connections and a melted spark plug wire that seemed to have been arching off the block. I upgraded the ignition system with Dynatek Coils, new condenser, wires, points, and plugs.

The issues I was having started about 8 miles into my ride. I had shifted to 4th and had to slow down with the flow of traffic. I downshifted accordingly but as I began to accelerate and try to shift up into third, I found a false neutral. Unfortunately I had to cut my ride short and head back. Ever since that ride, I have had issues finding gears with the exception of 2nd gear. Even Neutral seems to be difficult to find. The shifter has always been pretty stiff and clunky but I figured that would work its way out. If anyone can point me in the right direction I'd greatly appreciate it!


My other problem I found when taking the cover off on the rider's right side of the motor. I believe that's the clutch cover???? behind where the oil screen is I removed the clip and looked inside the cylinder coming off the crank. I found tons of gritty debris and scoring inside the cylinder. (I'm not sure what to call that part) It seems my bike doesn't have a screen. I'll look again tomorrow but that scares me and understandably so.

This bike is an heirloom and was the previous owner's dream to see it running again. So I'm trying my damndest to do this right. Two problems I know. Hope this doesn't confuse anyone.

Again, thanks in advance for any help you guys can give. It's greatly appreciated!
 

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Sounds to me like the clutch needs cleaning, greasing and adjustment. The front sprocket cover should come off, the lifter mechanism cleaned, fresh grease applied and the clutch adjusted as listed on the link: Honda CB450K5 Owner’s Manual (1972)
 

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Discussion Starter · #3 ·
Sounds to me like the clutch needs cleaning, greasing and adjustment. The front sprocket cover should come off, the lifter mechanism cleaned, fresh grease applied and the clutch adjusted as listed on the link: Honda CB450K5 Owner’s Manual (1972)
I've done all that. I adjusted the mechanism as close to the chain and sprocket as I could so that at full clutch it would still clear the chain. But then I had no throw in the clutch at all. I even took the other cover off and watched the clutch plates as I pulled the clutch and they didn't budge at all. I wound up having to shim the steel ball with about 6 washers so that I could actually engage the clutch. Does the clutch push rod have an indent where the steel ball meets it? Mine does and so does the mechanism.
 

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You shouldn't have to shim the ball, there should be plenty of adjustment in the cam on the side of the cover to get the system to work. If it HAS to be shimmed something is very wrong.

You adjust the clutch as follows, Loosen all cable adjustments until the cable is completely slack and all screws/barrels are completely turned into the housing and the handle. The Lever on the actuator inside the cover should be pulled down as far as its stop.

Loosen the 10mm bolt head on the outside of the cover right below the large slot in the barrel of the actuator and use a large screwdriver to turn said slot clockwise until you can feel contact, I turn mine just hair further so I can feel the clutch springs push against the push rod then back off about 1/8 to 1/4 turn on the barrel. Tighten the 10mm bolt head. Goal here is just to get them to touch and then back off, you don't want them touching all that time as this will wear out the ball and push rod.

NOW, reach up and grab the clutch and pull the handle back, DO not engage the clutch just find all the slack. AT the sprocket cover slowly take up the slack on the cable until the handle about 1/4/-1/2" from being completely open. Tighten the lock nut on the cover.

Now work through the clutch handle a few times and see if that is how you like the feel, you can adjust the handle at the lever if you want less travel before it engages or give more at the sprocket cover.


WHILE you are in the sprocket cover, look down at the shift shaft. There is a washer and Cir-clip that should be in place. IF the clip has popped out of its groove and allowed the shaft to move that can cause your shifting issue. If it did pop out GET a NEW ONE and replace it, don't try to bend it back and reuse it as they will just do the same thing again.
 

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I would also suggest that you open up the right crank case cover and inspect the clutch plates as well as the oil pump and filter.
 

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Discussion Starter · #7 ·
I tried the adjustments at the pushrod and literally had nothing. The clutches aren't frozen. I'm hoping they just need to be broken in. 42 yrs of sitting is pretty bad.

Today at work i removed 2 of the 6 washers. It felt much better at high RPM's. Tomorrow when I drive it back I'll remove the remaining 4 and see what happens. My clutch lever is extremely stiff. I knew the shims would be a band aide fix, just wasn't sure if anyone knew what caused that.

On my ride home from work today the bike did fine aside from the stiff clutch lever. But 15-20 miles down the HWY and shifting over 3rd was near impossible.

I checked for a screen or anything helping to filter the oil and my bike doesn't have any of that. In fact, when I pulled the cover off I can find a part with a female threaded part in the dead center with nothing in that hole. Is there supposed to be a screen there? And behind that I found a lot of trash and scoring. Almost looks like the possible missing bolt got chewed up. I'll have to see about getting pics tomorrow when I double check things at work.
 

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They don't have normal oil filters. They have centrifugal oil filters that spin particulates out of the oil. Do you have a manual? I know it goes over how to clean the filter.

How old is the clutch cable? Is it routed correctly without any hard bends? Is it lubricated? Did you check the Cir-clip I mentioned?
 

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Discussion Starter · #9 ·
They don't have normal oil filters. They have centrifugal oil filters that spin particulates out of the oil. Do you have a manual? I know it goes over how to clean the filter.

How old is the clutch cable? Is it routed correctly without any hard bends? Is it lubricated? Did you check the Cir-clip I mentioned?
Yea I did all that. Sorry, My laptop is being a pain allowing me to reply to this site. I have a new cable and it's routed properly. I did find the issue though and its pretty embarrassing.... The bad shifting was due to my shift lever vibrating loose. I put thread lock on the bolt on the back of the lever and called it a day on that. Rode it today for 30-40 miles and it didn't act up. To top off that simple fix, my shop foreman found I had the gear in improperly. Apparently you can have it in upside down. After cleaning the cover off I found the stamped letter upside down. My Clymer Manual doesnt give any reference points. It literally says "install". Embarrassing.... But I'm learning. Now I just have to adjust my carbs, but I'm running open header
 

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Dude, nothing to be embarrassed about, you fixed it. Savor the moment. When problems present themselves the causes are usually pretty simple. Sometimes the problems are buried and complex disassembly is required to gain access. Very rarely there is a major catastrophic failure the cost lots of money. There are a lot of great deals for old motorcycles out there that have not run for years and have easily fixed problems.
 

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No need to feel bad god knows I've been there more times than I can count. Nothing is lost when you learn something.

Take that Clymer and toss it in the trash and get a Honda shop manual, there are plenty floating around on the interwebs, I would link one for you but I'm rather far from my PC at the minute. Should be a link in the manuals section for the 450s on our site.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 

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No need to feel bad god knows I've been there more times than I can count. Nothing is lost when you learn something.

Take that Clymer and toss it in the trash and get a Honda shop manual, there are plenty floating around on the interwebs, I would link one for you but I'm rather far from my PC at the minute. Should be a link in the manuals section for the 450s on our site.

Sent from my SAMSUNG-SM-G891A using Tapatalk
IM your email to me and i will send you a .pdf. the early FSM are very instructional about why and how their bikes work. Call me a neard, but the 450 DOHC manual is a great read.
 

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Discussion Starter · #15 ·
True. I'm all-in so far about $1,800. That's including tires, tax and title, and even clear coat. Of course I have other parts I've bought as well, but not bad IMO for a bike. Glad the clutch issue is resolved, not to fine tune the rest of the bike and I'm good!

Thanks for the input! It helped me to narrow down the problem.
 

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