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Discussion Starter #1
I got my cx500 a few months ago and first time I ever rode a bike was in february. However, I have a degree in mechanical engineering and have always enjoyed DIY stuff so I have some basic knowledge and am trying to do all the work myself. I've fully taken apart the carbs, cleaned them, balanced them with a homemade manometer, and the bike is back running great (mostly). Since I don't have a full service record I just changed the engine oil to be sure, and I want to make sure the cams and timing are correct. My other concern is the RPMs which I assume is a clutch or transmission question.

1. The wiki on how to adjust the cam chain & valves wasn't detailed enough for me to be comfortable doing it myself. Does anyone have more resources on this subject?
2. My RPM at 60 MPH is about 7000 which seems very high to me. What is the typical cruise RPM and what might be causing mine to be so high?

Thank you for your replies!
 

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I'm sure the cam and timing (non-adjustable) are fine. There are some resisters built into the spark plug caps that can give you some trouble if they are bad. Check them out. I have a Clymers Manual and the adjustment procedure was easy (for the cam chain).
Your RPM seems a bit high. I would suspect an inaccurate tach or a slipping clutch. My 500 seems to carry speed at about .011% of RPM, hence 6,000 RPM = 66 MPH approx. This is about the bottom of the power curve (RPM wise).
What year is your beast and how many miles on it? There is a fairly predictable service life on several items that greatly affect your bikes performance.
 

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Discussion Starter #3 (Edited)
Its a 1980 deluxe, with about 26,000 miles. It seems to have been pretty well taken care of but as my question indicates I'm trying to do all the regular maintenance stuff just to make sure. What might you recommend beyond checking the cam valves? I plan on replacing the final drive gear oil soon.
Also, when you say bottom of the power curve.... how is that possible since 6000 RPM is 2/3 of the way to redline?
 

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My cam chain seems to be all right. I have adjusted it. There is a video of adjusting it on U tube. My bike has 48000 miles on it. Adjusted maybe 3 times ever. Check the free travel on your clutch. Should be able to move the little lever down on the right front of the engine a little by hand and when you pull the lever it should move easily and then get harder. Free travel shows you that the clutch is fully engaged when the lever is released. If there is tension when lever is released that means it is going to slip when you pour the coal to her. You can adjust free travel, see if you can get about a quarter inch.

1980 CX500 Deluxe
 

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your cam chain would probably benefit from adjustment, your planned fluid changes will also be a good idea. I don't think there are enough miles on the bike to be concerned about too much but do check over the rubber/plastic/neoprene items, they are ozone/sunlight affected with age.
These little engines are highly tuned which moves the power band towards the top of the RPM range. They don't have much torque or power below 6,000 RPM. Just spin and grin!!
 

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Discussion Starter #6
I have a little bit of travel on my clutch so that shouldn't be an issue. I checked the RPM at 60 MPH again and its more like 6600 RPM which still seems incorrect as most users are reporting RPMS lower than their MPH? However I found one bit of info suggesting the 5th gear for these bikes is about 0.9 something which means RPM should be a little higher than MPH so how does everyone get so much lower RPMs?

Next, I'm thinking of wrapping the exhaust pipe. Has anyone had problems fitting exhaust wrap on these bikes? There isn't much room for wrap between the pipe & the flange that secures it to the engine.
 

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The final drive ratio gives rpms about 10% less than mph, i.e. 5k at 55mph.
Adjust valves with engine cold, left side first with engine tdc on compression as described in the factory service manual. Adjust the cam chain in this same crank position. Then put the right side at tdc compression and adjust the right side.
 
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