CB200T - Just getting started

2BrokeBikes

2BrokeBikes

Veteran Member
Joined
Oct 15, 2021
Total Posts
344
Total likes
342
Location
Portland, Oregon, USA
Hi, everyone. I've got a '75 CB200T that I picked up for a good price that I'm getting ready to fix up and make a daily commuter. Right now the engine is seized and is soaking in Marvell Mystery Oil. The PO said that it turned over as recently as last Spring (2021). Hopefully I can get it to turn over in the coming weeks. If not, then I'll be posting a much less naive sounding post here soon.

Any advice/warnings you all might have about getting a seized engine unstuck is most welcome.

I'm in no rush, since it's the start of the rainy season here in Portland, so I'm taking my time with the research and prep phase of my project. I've downloaded and printed out the FSM and Parts Manuals, and gotten a Clymer manual. I'm also getting my garage sorted out, organizing my work space and getting the tools I'll need. If you all have any recommended sources for quality tools for working on bikes from this era, let me know.

As a sidenote, my dad passed away a few years ago and the giant toolbox full of Snap-On tools he used when he was a Rolls Royce mechanic has been sitting untouched in my mom's garage halfway across the country. It kills me that, now that I have a legitimate use for them, I can't get to them! I think there's a road trip coming up for me. Maybe sooner than later...

Anyway, this post, from mannydantyla , (thank you!) recommends checking the compression after I've changed the oil and replaced the battery. I don't know what to look for when buying a compression gauge for the CB200. Any suggestions?
 
Moved to Smaller Twins Engine and Transmission section.

You don't need a really expensive compression gauge, just not a cheapie. The length of the hose will also affect your readings. Remember to hold the throttle wide open and kick (or turn with the electric start) until the gauge reaches its maximum reading. All those Snap-On tools will be worth the road trip, they're top quality and I'm sure you're thankful to have them available to you. I was in a similar situation when my father passed in early 2016 though his tools were more body work related and less general mechanical, and he never had the money to spend on high end tools like Snap-On but I'm very grateful to have them just the same. You're not really in need of the Clymer manual unless you want a good beer coaster for the garage, the FSM and any clarification you'll need from experienced members here will fit the bill for you. After the engine soaks for a while, be as gentle as you can be in breaking it loose at first. It's highly possible it will be okay if it turned over in the last 9 months or so, but if the carbs or exhaust has been off the engine for that period it will probably be worse due to the dampness exposure.
 
2BrokeBikes said:
If you all have any recommended sources for quality tools for working on bikes from this era, let me know.
Click to expand...

How about giving a basic account of tools you have as a starting point? Here are a few things I didn't own when I got my first vintage bike, but now get used all the time:
-hand impact tool
-feeler gauges
-quality crimping tool
-chain tool
-torque wrench
-set of circlip pliers.

A voltmeter is extremely useful also. I tend to set timing on my points using a voltmeter rather than a timing light.
 
I've got a cordless impact driver, feeler gauges, large torque wrench, and volt meter. I'll see about getting the rest. Thanks for pointing me in the right direction.
 
2BrokeBikes said:
I've got a cordless impact driver, feeler gauges, large torque wrench, and volt meter. I'll see about getting the rest. Thanks for pointing me in the right direction.
Click to expand...

Even with a cordless impact driver you will probably find occasion to use a hand impact on crosshead bolts on your side covers and other parts. It's easy to strip the heads with a screwdriver or power tool and the hand impact helps remove them without damage.
 
stl360+450 said:
Even with a cordless impact driver you will probably find occasion to use a hand impact on crosshead bolts on your side covers and other parts. It's easy to strip the heads with a screwdriver or power tool and the hand impact helps remove them without damage.
Click to expand...

Looks like I'll be making that trip back to Colorado to pick up my dad's tools sooner than later...
 
LongDistanceRider said:
Use a 6 point 1/2" drive socket on a long breaker bar. Don't bounce it because that will loosen the bolt when turning forward, left.
Click to expand...

Agree, and be gentle initially since at this point you don't know how badly it is stuck, you want to break it loose but not do any damage
 
Added a couple of JIS impact drivers to my shopping list after having flashbacks to stripping out the cross-head bolts on previous bikes...
 
Okay! So, some tools finally arrived and after letting the pistons soak in MMO for a couple of weeks, I took off the alternator cover and was able to get the engine to turn over by hand. It was a little crunchy at first but became smooth after a couple of slow rotations. I'll take it! While I'm waiting for my dad's old compression tester to arrive from Colorado, I'll see about getting it ready to turn over for a compression test: new plugs, new battery, fresh oil, get throttle cable unstuck, etc.

A couple of questions maybe you all could answer:
1) When I took the alternator cover off, a bunch of oil came out. Is there supposed to be oil in there?
2) The oil was cloudy and smelled like old gas. Could that indicate that the piston rings are shot and fuel has been leaking down into the crankcase, that there's a possible leak elsewhere, or is it normal for there to be some fuel in there after it's been sitting for almost a year without turning over? Maybe the PO repeatedly flooded it?

Thanks for helping out a rank amateur!
 
First, drain and change that fouled oil....... Somebody didn't turn off the fuel petcock.....

Yes, there is always some oil around the alternator... It lubes the chain and starter clutch.....
 
2BrokeBikes said:
A couple of questions maybe you all could answer:
1) When I took the alternator cover off, a bunch of oil came out. Is there supposed to be oil in there?
2) The oil was cloudy and smelled like old gas. Could that indicate that the piston rings are shot and fuel has been leaking down into the crankcase, that there's a possible leak elsewhere, or is it normal for there to be some fuel in there after it's been sitting for almost a year without turning over? Maybe the PO repeatedly flooded it?
Click to expand...

1) It's normal for some oil to run out when the alternator cover is removed. The oil level might have been higher than normal due to the marvel mystery oil you added, which would make its way down to the bottom of the case. Oil can go anywhere inside the motor cases.

2) The cloudiness makes me think that there may be some water in the oil, but it could also be fuel or the fresher marvel mystery oil. I'd rather wait for the compression test than speculate about what that implies, but you might post a picture to give us a sense of how much oil came out and exactly what it looked like.

Am I correct in thinking that we don't know how long it's been since the oil was changed? The motor supposedly turned over in the spring, but were you told the last time it actually ran?
 
stl360+450 said:
Am I correct in thinking that we don't know how long it's been since the oil was changed? The motor supposedly turned over in the spring, but were you told the last time it actually ran?
Click to expand...

Thanks for the guidance. I'll be sure to get a picture and post it here next time I take off the alternator cover.

I think the PO said it started and ran last April, but I'm not sure. I've got no idea when the oil was last changed.
 
I changed the oil, and once again forgot to take pictures. Sorry about that. I hope a description of this will suffice. There was a bunch of white goo collected in the oil drain plug, pretty thick, too. I plan on changing the oil again after whatever else needs to be done, so I'll report back here (with pictures!) what I find.

In other news, the engine turns over smoothly, I've gotten a new MotoBatt battery, changed the oil, and bought an Innova compression tester. When I do the compression test, what numbers am I looking for to tell me if compression is good or not?
 
ancientdad said:
Moved to Smaller Twins Engine and Transmission section.

... Remember to hold the throttle wide open and kick (or turn with the electric start) until the gauge reaches its maximum reading.
Click to expand...

AncientDad, the throttle cable is gummed up on my bike, can I just remove the carbs while I'm running the compression test?
 
Can't specify as it depends in the test equipment and how well you follow the correct procedure.....

Actual (corrected for hose length) compression should be @ about 170 PSI..... but actual gauge reading could be @ 120 PSI or worse.....

Carbs can be wide open OR removed....Either works....
 
You must log in or register to reply here.
Back
Top Bottom