Topic: Its been asked..

[mrblasty]

This is my second posting . I am thinking of buying my buddies 71 cb750. I was talking to him about the bike and and he says the thing had been sitting for 3years. If the bike was running when it was parked should it be to much trouble to get it running again.
I know this has been asked a thousand times before,I just don't have a lot of time to scan the postings. Any direction on the matter would be greatly appreciated.

[rob]

Hi,

I just got an '81 CB650 Custom going after 1.5 years of sitting, and it was running when it was parked.  I think a lot is going to have to do with the environment it was in.  If it was well protected from the environment, in a nice heated shed with very little moisture in the air, you may have little trouble.  If it was outside under a tarp in the pacific northwest, you may have more trouble.  It also depends if any work was done on the bike to prepare it for a long sit, or if it was just parked as is, with dirty oil, etc.

Essentials I would say, would be to change the oil and oil filter, clean the gas tank, check the brakes.  Then perhaps try turning it over to see if the engine cranks, and get the oil worked in, and try to start it up.


The brakes may give you a bit of a headache, as the brake fluid attracts moisture and the parts get rusted and seized pretty easily.  You'll probably have to clean out the carb, oil the drive train and possibly change the chain,  replace or lube the clutch and throttle cables, and maybe clean the electrical system if its the connections have some corrosion.

If you haven't got it yet, get the Clymer service manual for the bike on Ebay or new, its worth its weight in gold...

Have fun

Rob

[Raul CB750K1]

mrblasty, welcome to the forum. You've done the right thing: if you don't have time to search in the old thread, just keep asking. This forum is full of people with nothing better to do than to answer the same ol' questions all over again...;-)

Raul

P.S. I second Rob's opinion. Three years doesn't seem time enough for the pistons to stuck, but you never now. If the engines moves freely, an oil change, fresh gas and probably new battery will be enough. Carbs will need a rebuild almost for sure. You can go later for tyres if they are hardened and the rest of usual things (brake fluid etc)

[basz500]

Shouldn't be anything to get it on the road again.  Get a good manual, clean the carbs well, change oil, fresh gas...vroooomm!  My '72 CB500 sat for 21 years and I brought it back to life without too much heartache.  After you get it running, do a good burnout to celebrate, then get new tires.

Cheers,

Pete

[jgary]

I'm working on one now that had been sitting for 3 or 4 years.  First thing was to take the tank off & drain out all the old gas.  Next I had to replace fuel lines, since I ended up cutting the lines to get the tank off.  I replaced points and condensers, although I probably could have just cleaned the points up.  Plug wire end caps and plugs were corroded, so I got new caps and plugs.  Took the petcock apart and cleaned it out with a pipe cleaner.  Started the bike!  Clutch was frozen, and to free it I changed the oil & let the bike run for a few minutes with new oil.  Clutch came free pretty easily.  Front brake caliper was frozen.  That's currently being rebuilt.  Front brake master cylinder is rusted up, and I'm still trying to get it apart.  Cam chain adjustment, valve adjustment, clean the chain, and I think I'll be ready to go.

John.

[rob]

Having the master cylinder/caliper seized seems to be a fairly common problem.

If someone was going to have the bike sit for longer than a year, would it be advisable to drain the brake fluid and loosten all the bolts so that this wouldn't happen?  Or is it worse to have it exposed to the atmosphere?

Rob

[MetalHead550]

Good question Rob.  I would say its best to leave the break fluid in and keep the system sealed up.  I would think the fluid keeps the various seals and O-rings, and lines themselves from drying and cracking and dot 3/4 generally attracts moisture as it is, so having any openings in the system would just make it that much worse.  Dont take my word for it though, mabey some of the pros will let us know.   

[Bob Wessner]

I'm certainly no Pro, but I would agree with keeping it sealed and filled. Assuming the fluid were fresh to begin with (probably a bad assumption) 1-3 years ought to be OK, but it would have to be drained and refreshed for sure. I would think draining, or open connections would be an invitation to corrosion.

[cb650]

I would say if the fluid is replaced before storing there is a better chance of having good brakes.
These bikes where riden for 15yrs then sit for 10 with all that crap in the system.  Most people dont even know the fluid should be replaced ever.  First thing I do with any vehicle I plan on keepin is flush the system and then chase the leaks.




                    Terry

[Kevin D]

My 71 fired right up after a 15 year park. Cleaned carbs, petcock and tank, new battery, fresh gas, new tires, scraped old jellied brake fluid out of reservoir and replenished with new, opened bleed screw and pumped new fluid in, no leaks, lotsa stop. I found lots of help here in SOHC4 archives and daily posts, MANY THANKS to you all.

[chippyfive50]

Bought a K3 with 8000 miles on, the motor was not seized, so I surrenderd my $100!, it sat for 12 years. New battery, new gas, 2 kicks and it fired up. I immediately gave it a HEAVY tune up and alot of cleaning, but it runs great. I have since bought 2 more, with similar results. These bikes like to run....
 

[phylo101]

Hi. New plugs first off. When youre changing, squirt a TINY bit of diesel (derv) down each bore if she seems a bit sticky on the kicker, this ungums the old crap in the ring grooves. Remove the plug caps carefully by unscrewing. Clip a quarter of an inch of each lead and reattach. Replace the battery entirely, dont try to charge or revive for its first start, deal w that later. Youll probably be churning it over for a while to start it so you need a new batteryload. Clean and refill the tank before this...so that when u pull the old plugs and all four are wet, then youre ok, the petrol is getting thru the carbs if you kick it over a few times not switched on. If theyre dry, youll have to pull and clean the carbs, because three years is CERTAINLY enough for the carbs to varnish up with the crap that distills out of unleaded gas, cos if its ONLY three years then I guess thats what she was running on before. At the VERY least drain each carb bowl using the little drain nut.

Brakes - open reservoir lid fill to brim, undo two halves of caliper and let it hang down...then start to pum and blow the piston out. Youre gonna have to remove all the crud off the piston with fine glasspaper. Big grooves etc are ok, just get rid of ALL the brown/white crud down to the metal, very carefully. pry out the rubber seal from its groove in the caliper, and clean the groove, run a bit of glasspaper around the inside of the caliper. Put the seal back in - theres no right way cos its the GROOVE thats cut biased to make sure the inner edge of the seal sits up. Start bleeding thru from the master cylinder using fresh DOT FOUR fluid, the system can take it and it helps. After a while when youre fed up of #$%*ting your pants every time you go out, fit braided stell hose, cos the old hose will be weak and buging rather than passing fluid lol

(The best tuning mod you can do is improving your brakes - its amazing how quick the bike will go when you KNOW itll stop!)

phylo

[mrblasty]

thanks for the info guys.