Topic: 12 years not running, started RIGHT UP, incredible

[Hondawggie]

The cb900c I've done some work on with your folks' help -- today was the make-or-breaker.

Here's what I did with this 1980 cb900c:

- got it from the original owner, he was on a longish cruise and all the power went out in early 1998, he went to a lot of trouble being stranded in the middle of nowhere to rescue himself and the bike, and was pissed and left the bike sitting from then until about 4 weeks or so ago when I got it.

- It had been inside and outside, it was on his driveway under an evergreen tree with a plastic tarp on it -- cobwebs everyhere, there were evergreen needles everywhere, in all nooks and crannies

- I got it home removed the touring fairing and got the electrics and the headlight and turn signals re-installed and working -- turns out the reason the bike stopped on him in 1998:  two blown fuses

- I cleaned it up surprisingly the gas tank, fenders, wheels, gauges no fade, paint looks brand new after cleaning, just some oxidation atop the CV carbs

- disassembled/cleaned/reinstalled the front brake calipers

- pulled a 2-year-not-used Yuasa battery out of my junker project 1982 cb900F and filled/charged it, put it in the cb900c

- the gas tank was 1/3 full of.......VARNISH.  I used lacquer thinner in there, sloshed it around for 1 week every day

- then the petcock was clogged, so today I boiled it in water with malt vinegar, fixed that problem

- installed a new gas line and inline fuel filter -- hit the start button, will the 2-year-old Yuasa work?  Will the bike even fire?

Darn thing fired up immediately.  Took it around the block, monster power, has a gleaming chrome Kerker.   12 YEARS of not running and it started up like I just drove it an hour ago.  INCREDIBLE MR. HONDA.  Incredible.

Bike has 9853 miles.  

I put off trying to start it until it could be driven on the road with working lights and signals.  Huge reward today, after a few weeks of my scattered spare time fixing the electric and lighting issues,  the bike sounds and runs great, thanks to you guys for your help with the electrics and the exhaust studs and the 'no power' problem.    Will get some pictures tomorrow.

Get this.  THE CARBS HAVEN'T EVEN BEEN CLEANED.  And yet this sucker runs, no hesitation anywhere, idles excellent, runs through the pilot/needle/mains no hesitation, wow.

I really took a chance on the carbs, what with the gas tank really gummy with varnish as I found it.  I probably should pull them and clean the bowls at least, I wish I could get a screwdriver the right size that would allow removing the 4 floats bowls without removing the carbs.

[Retro Rocket]

Well done mate, good story... I had a 900 for a couple of years in the 80's and apart from having a slow weave at speed it was a great bike and i had no trouble with it at all....

Mick

[MCRider]

Change the oil?

You might not be out of the woods yet. If the fuses blew once there is usually a reason.

But I mentioned in another thread, I really like the CB900C and wish you the best of luck with it!   

[MoMo]

CB900 is a great cruising bike, you were very lucky the carb intake boots weren't cracked.  I've worked on three 900s in the past three years and all had cracked boots.  Have fun,  Larry

[Hondawggie]

whoops I did forget all about changing the oil although I checked it when I got it and the level at least was fine, well I only took her around the block so no harm done and thanks for the reminder.  I'll have to buy/install a new oil filter and a new air filter won't hurt.

There were 2 fuses that were actually broken, not burned through. I think vibration or maybe the box of fuses he bought got dropped in the store or something.  

The big fear I had with this bike was just this issue -- why did it lose electrical power back then in 1998, and would I be able to find it and fix it.  BIG question mark for me.  

So I found the location of the fuses (under a plastic cover right at the middle of the handlebars).  They sit there in the fuse box in such a way that all you have to do is look down and you can see if the filament is burned through creating an open circuit problem.

When I looked at the filaments of all the fuses, NONE were burned open so I right away thought, "Of course I aint gonna get lucky like that, it will probably take me a month to find the problem."

And because I don't trust my eyes I decided to pull the fuses anyway and use my ohmmeter to make sure they weren't burned open.  Well on two of the fuses, the metal cap on one end of the fuses was loose.  Never seen that before, didn't know if it was a problem, then the end cap fell OFF two of the fuses and I cheered up -- put in 2 new fuses and sure enough the power was there.

So in this case I'm hoping it was vibration or a bad set of fuses -- time will tell.

[Grnrngr]

I've had that happen to lots of glass fuses...congrats on gettin her up!!

[333]

Clearly the PO either drained the gas or ran it dry.  That's the only explanation for not needing a carb overhaul.  Good goin'.




I always wanted a 10 speed.

[754]

If its got compression, fuel & spark, and you turn it fast enough.. it should start..

 With a Honda, Its not a surprise..

[Hondawggie]

Clearly the PO either drained the gas or ran it dry.  That's the only explanation for not needing a carb overhaul.  Good goin'.




I always wanted a 10 speed.

I'm looking forward to trying out the hi-low!  I'm not even sure how to use it!  Do I pull in clutch?
Are you supposed to click it into the 'high' gear while accelerating just like you shift from, say, 4th gear to 5th gear?   And do you click in out of 'high' gear when decelerating, like you do to downshift from, say, 4th gear to 3rd?

Or are you supposed to start the bike, choose the Hi or Low gear before you hit the road, then have to leave it alone until you stop?

I have no clue how to shift from Hi-to-low.   I do know in my 1998 Jeep Cherokee (not Grand Cherokee), I have to be stopped before moving between the high and low range of the tranny.

[wardenerd]

A friend of mine has a ten speed .  He keeps it in high and swears hi/low is just a gimmick.

[Hondawggie]

Okay here's the source of my work these past couple weeks:


Looks great from this distance, but it needs some detailing and touch-up semigloss black paint in spots, and aluminum polishing.


Also I need to get the back brake fixed, I tried to bleed it but nothing at all comes out of the rear bleed nipple.  I filled up the rear brake's reservoir and the brake pedal depresses all the way to its mechanical stop with no resistance, and no fluid comes out of the bleed nipple and the pucks don't move.

Today I rode her for my 2nd time ever and the front brake feels SUPER spongy.
This bike has dual front calipers and until this bike I never did dual-front brake bleed job.

So here's how I did it after I removed/cleaned/reinstalled the 2 front calipers
- first I bled the left caliper and ignored the right caliper
- then after bleeding the left caliper, I ignored it and bled the right caliper

Was that correct?

Is the reason the front feels spongy is still air left in the lines, and how can I tell which caliper is the culprit?

[MoMo]

You need to disassemble all three brakes and clean out the residual crud.  And, yes, the 10speed is a gimmick, Larry

[weekend_junkie]

Clearly the PO either drained the gas or ran it dry.  That's the only explanation for not needing a carb overhaul.  Good goin'.




I always wanted a 10 speed.

I'm looking forward to trying out the hi-low!  I'm not even sure how to use it!  Do I pull in clutch?
Are you supposed to click it into the 'high' gear while accelerating just like you shift from, say, 4th gear to 5th gear?   And do you click in out of 'high' gear when decelerating, like you do to downshift from, say, 4th gear to 3rd?

Or are you supposed to start the bike, choose the Hi or Low gear before you hit the road, then have to leave it alone until you stop?

I have no clue how to shift from Hi-to-low.   I do know in my 1998 Jeep Cherokee (not Grand Cherokee), I have to be stopped before moving between the high and low range of the tranny.

The high-low is a 2 speed sub-transmission, use it just as you would the 5 speed main transmission.  It was an added 'feature' to allow honda to use the shaft swingarm from the goldwing.  It just connects the engine output from the left side to the shaft/swingarm on the right side.

[Hondawggie]

You need to disassemble all three brakes and clean out the residual crud.  And, yes, the 10speed is a gimmick, Larry

The front calipers -- I already removed both of them, disassembled completely include the oring seal for the brake pucks and cleaned their grooves and everything else -- they work fine, ie. they squeeze the disc rotor then release the disc rotor when I squeeze/release the brake lever.

FEELS SPONGY and I'm losing front stopping  power because of that.

HOW DO YOU BLEED a twin-caliper motorcycle? 
I described my process I used above and I still might have air in the lines because I've got this bad sponginess in the front brake -- is my procedure (repeated here) correct for bleeding a twin-front-discs motorcycle?   

Here's how I did it after I removed/cleaned/reinstalled the 2 front calipers
- first I bled the left caliper and ignored the right caliper
- then after bleeding the left caliper, I ignored it and bled the right caliper

Was that correct?

[754]

 The low range would be Extremely nice for sidecar use..

[MoMo]

HW,   I usually do the right first and then the left.  There's a trick a picked up from this forum for bikes that for some reason seem difficult to get that final firm feel-that is to tie a cable tie around the lever overnight, not so tight that the lever hits the grip but tight enough so the lever is maybe a finger away from the grip.   One of my Silvewings was particularly troublesome and I did that for two nights, the feel is rock solid now. When I bleed I slowly pump, stop pumping , open the bleed valve and squeeze the lever.  It seems that less air is created that way..and it takes much less time to get brakes.  Are sure the little hole in the mc is clear?  Larry

[Hondawggie]

HW,   I usually do the right first and then the left.  There's a trick a picked up from this forum for bikes that for some reason seem difficult to get that final firm feel-that is to tie a cable tie around the lever overnight, not so tight that the lever hits the grip but tight enough so the lever is maybe a finger away from the grip.   One of my Silvewings was particularly troublesome and I did that for two nights, the feel is rock solid now. When I bleed I slowly pump, stop pumping , open the bleed valve and squeeze the lever.  It seems that less air is created that way..and it takes much less time to get brakes.  Are sure the little hole in the mc is clear?  Larry

I get the feeling it's just air in the line.   Tomorrow I'm going to re-bleed and I'll with the right side caliper per your suggestion, the right caliper is closest on the brake-line-splitter to the brake hose that drops down from the master cylinder, so maybe all the air's on that side. 

I though I had this bike's front brake nailed, here I am at it again.

[fastbroshi]

Cool, I bet you got that bike for a song!!

[Hondawggie]

Cool, I bet you got that bike for a song!!

all the junkers I bought here and there like a sucker I guess I'm due for some 'good luck'

What I notice about this bike is -- it has lots of power, weighs a lot, comfortable riding position, not 'edgy' enough.   I guess if I paid as much dues reviving vintage machines as I thought I did, it would have been  a mint-condition '71 cb750.   If you like a powerful cruiser this is it.  If you like a quick throttle responding, rip your arms out the socket white knuckler this aint it

[Hondawggie]

HW,   I usually do the right first and then the left.  There's a trick a picked up from this forum for bikes that for some reason seem difficult to get that final firm feel-that is to tie a cable tie around the lever overnight, not so tight that the lever hits the grip but tight enough so the lever is maybe a finger away from the grip.   One of my Silvewings was particularly troublesome and I did that for two nights, the feel is rock solid now. When I bleed I slowly pump, stop pumping , open the bleed valve and squeeze the lever.  It seems that less air is created that way..and it takes much less time to get brakes.  Are sure the little hole in the mc is clear?  Larry

I got this front brake bled pretty well now.  Like was suggested I did the right side caliper first being closer to the downtube of the master cylinder, shortest path for air bubble to go.  Then bled the left side.  I did have air bubbles in there.   Now the front brake is a lot less spongy, thanks for the advice.

[MoMo]

Glad you have solid brakes now as it takes damn good brakes to bring one of those beasts to a halt.... Larry

[rchrdms]

Beautiful bike. Nice find.