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Good afternoon all,

Couple of questions I'm hoping for suggestions on. My dad's got an old Honda CB900 Custom in the garage that I'd like to fix up this fall. There were never any mechanical issues, no crashes, etc. He stopped riding about 12 years ago and it has simply sat in the garage since. Obviously it doesn't run now. There is no external rust that I can see.

Question is this: if a bike sat that long without being run or touched, what potential problems might there be that need to be addressed? What might need replacing, or cleaning, etc? Obviously there's not a lot of detail for you to go off of, but just curious if anyone might be able to give me some issues that would immediately come to mind. Any thoughts on what it might possibly cost to get it running again?

Second question sort of follows in step. I don't currently have much mechanical experience of my own at the moment. I'm not completely inept (I can change the oil, battery, fuses, etc. in my car), but I have no background, I never studied it. I would really like to be proficient enough to fix up and maintain my own bike, however, does anyone have any suggestions on books, classes, websites, etc. that might make this easier?

Thanks for reading, and I look forward to your help!

Tom
 

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I'm certainly no mechanic either but with these older bikes they are actually not too tough to work on. Buy a Clymer manual or buy a 1 year subscription for an online manual like cyclepedia.com
Best thing you can do is become friends with an older hobby mechanic who's been working on his bikes for year who will help you for free (or cheap). Having someone help you learn how to do things the first time can be a real help. Seriously though, just dive in, how much damage could you really do?? :)
Toran
 

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I would have posted you the actual link to the manual but you have to have at least 15 posts to add a link to a post... Mods... some of these rules just seem plain silly... what am I missing??!??!!
T
 

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If there was fuel left in the tank, it will likely need to be cleaned out, and the carbs rebuilt.

The oil should be changed and the brake fluid flushed.

The tires should be replaced.
 

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The CB900C is a very interesting bike: 10 speed transmission; OEM oil cooler; and just a beautiful bike all around. Congratulations!

Now, about making repairs...

1) Assess the gas tank: shine a flashlight in it to look for surface rust. Unless the tank was filled to the top, prior to storage, it likely has some rust. If it has too much, even a liner won't save it, and that would be a shame. Tank liners are a complicated topic, so search the Internet for motorcycle tank rust solutions, or some such, and read heavily, before you do anything.

2) Assuming the tank can be salvaged, the gasoline will have turned to varnish, even if a stabilizer was used, so you will want to flush out the tank with acetone, a solvent, which can be purchased at your local hardware store, or Wal-Mart, in the paint section. Search the Internet for more specific directions.

2A) Make sure the engine is not seized: put a good, fully charged battery in
it (the old one is toast, don't waste your time with it), and see if it turns over. It
won't start, but if it turns over, the engine is not seized, and it is not an 800#
paperweight! Proceed down the list...

3) Get yourself a copy of the Factory Service Manual for that bike model and year -- search the Internet, as it may be available for free, or you can pay for a PDF copy for most bikes, which are still available. You need the OEM Manual, if at all possible. Clymer, and Haynes are good supplements, but there is no substitute for the OEM.

3A) Use SeaFoam, as a solvent/cleaner by adding 2 oz. it to the fork tubes prior
to draining; manually compress the forks several times to circulate it throught the
forks, internally, then drain, as per the manual, and put in fresh fluid.

3B) Add SeaFoam to the crankcase oil, prior to changing it out; this should be
done after the carbs are repaired, as you will need it to run. The SeaFoam
will dissolve carbon deposits, varnish, etc., from within the engine -- run it for 5
minutes on the center stand, idling, shifting through all five gears, and then shift
into the high range, letting the rear wheel spin freely -- this will circulate it
throughout the engine, and the transmission. It will also turn your oil coal-black --
change out oil and filter to remove the crud dissolved.

4) Change all of the fluids, including brake fluids, fork oil, shaft drive lube (a gear oil, easy to do, little volume required, but it is critical -- see OEM Manual), as well as engine oil (see above). Chances are very good that the brakes will need to be disassembled to clean out dried/gunky Brake Fluid. Use only DOT-3 fluid, which will function as a cleaner for the parts (this is why you will want/need the OEM Manual). Use an old toothbrush to gently scrub the parts with fresh DOT-3 Fluid, to get the gunk out. Wear nitrile gloves to protect your skin, as well as a face shield.

5) Get yourself a clicker Torque Wrench. Harbor Freight sells them for around $20. You need to properly torque everything... Never guess, never just turn it 1/4 past finger snug... Apply the proper torque -- always, on every bolt! This is why you need the OEM Manual -- it lists the proper torque for everything.

6) The carbs will need to be removed, disassembled, and cleaned properly. YouTube is your friend!!! Search it for videos on everything you will want to do. There are excellent videos on cleaning carbs, as well as synchronizing them afterwards, on YouTube. It also has videos on: oil changes (my Kawi Voyager has two oil drain plugs, for example, so check the OEM Service Manual, for all procedures, prior to starting...); brake fluid flushing; cable lubing; etc.

That's a good starter list. Here is a web site, which is likely your best source of information on the CB900C, but see my caveats after the link...

www.cb750c.com

These folks are incredibly knowledgable, but they will not tolerate questions on subjects they have alreadly covered, ad nauseum, over the past 20 years! Read their rules, carefully... Use the "Search" function judiciously. When you ask a question, couch it by saying that you used the search function, but couldn't find the answer. And wear your asbestos shirt and pants, and brace for a fiery response if your search-fu failed. Cheers!
:coffee:
 

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excellent advice

I couldnt have said it better. When I started with my 78 kz650, I decided right then. Im going to learn my bike... EVERYTHING... About my bike..... Whats the worst you could do... You have to be all in or all out
 

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My 1982 honda cb900c has the same problem ....when the starter is on a table it spins when i put it on the bike it wont spin and the power wire becomes grounded.....i need a solution??? It doesnt seem to be grounded anywhere doesnt seem to be any shorts. Thank you for any answers to point me in the right direction before i push it and me into the columbia river!!!!!
posted now
 

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Help I have a honda cb900c but my 4 carbs are overflowing and I did also bypassed the automatic petcock, i dont have the gas tank connected i am feeding the gas with a bottle straight to the gas line and i also have the vaccum nozzle caped off but my motorcycle wont start, however i spray some gas on the carbs and i got started for 15 seconds max i was wondering if you guys could help me out with this issue this is my first build and i want to start riding but i just havent been able to get it started.
 

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So I am having a problem with my bike and I'm not particularly mechanically inclined. The engine won't turn, and I replaced the battery and emptied the float bowls. Any ideas as to what the problem could be?
 

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So I am having a problem with my bike and I'm not particularly mechanically inclined. The engine won't turn, and I replaced the battery and emptied the float bowls. Any ideas as to what the problem could be?
Ideas? Yeah. Pretty much any/everything. You've not even cracked teh surface.

I don't want to be the rain on the parade here, but let's be real. As a guy who restores and sells vintage japanese bikes for a living, I can tell you a "good" condition, running CB900C is worth about $2,000. A museum-quality pristine one is maybe $3K. The older CB750's are the ones that are "hot" right now and have big money in 'em. The 900 is an also-ran oddity that has its fans, but doesn't command the prices.

SgtSlag's list is an excellent start. But the bottom line is this better be a labor of love, 'cuz it's not 'worth it' in any sense of the word. Just in parts/rebuild kits/fluids/etc. you're gonna be into it way more than the bike is worth to get it running again.

Don't get me wrong: I love 'em. I think it's a great balance of displacement versus revs, I think the inline-4 CB engine is hard to beat in general. I think the big old heavy carbs are great and you can rebuild them for eternity and they'll keep working. I think the 10-speed tranny is super-cool, and I really like the look of the bike. I'm a fan, but I'm also a realist.

Money-where-my-mouth-is time: I currently have an '82 CB900C in excellent cosmetic and running condition: It's an 8/10 bike. Someone shows up with $3K cash money, they're riding it home. You can't fix up a multi-year non-runner for that.

Sorry to be the grinch here. Just sayin.
 

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To Casey Jones, Is your 1982 CB 900 Custom still available? If so, I am very interested in purchasing it for your quoted price of $3000. I have just registered on this forum.
My name is Kenny. If you still have it, or you may have another in the future, please contact me at my email.
Thank you very much.
 

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Retired twice: Navy and as a govt contractor
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Kenny, Casey hasn't been back since March 2018
 

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Wow, invasion of the zombie posts tonight!
 

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Wow, invasion of the zombie posts tonight!
Almost like power posting to get enough posts to put up an image one might think.:devil:
 

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My 1982 Honda cb900c has the same problem ....when the starter is on a table it spins when I put it on the bike it wont spin and the power wire becomes grounded.....I need a solution??? It doesn't seem to be grounded anywhere doesn't seem to be any shorts. Thank you for any answers to point me in the right direction before i push it and me into the columbia river!!!!!
posted now
I have had Honda's b4, way remember it is it has some sort of clutch that when starter spins, the
pinion gear spins OUT to mesh in with flywheel or bike's starter gear, I think you need a new starter
clutch. Or maybe but I doubt it, The starter has a solenoid mounted on it that does two jobs.
1 completes circuit from battery to starter and

2 pushes starter gear out to mesh with large ring gear for cranking the engine

I had a CL360 Scrambler but maybe the larger engines used a different type of starter.
 

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I have just finished rebuilding a 1980 CB900. Engine, clutch, forks, brakes and rear air shocks. It is only painted in primer so needs finishing. I love the bike but my boss (Wife) says as I have 4 others I should sell one. I rebuild bikes for fun and don’t expect to make a profit but I believe the shaft drive 10 speed is somewhat sought after. Any suggestions would be appreciated on asking price.
 
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