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Al
04-01-2012, 10:43 PM
Hello BCMers.

After nearly 2 years since the loss of my 07 Sportster, I wanted a motorcycle again. I bought a Honda CB900C.

http://www.brewcitymuscle.com/forum/attachment.php?attachmentid=7918&d=1333337176

Year: 1982...same as me
Miles: 42,000...not sure if actual
Looks: as if it's been gone over with the ugly stick.
Engine: Noisy, needs valves adjusted. Drips oil from valve cover to exhaust and makes smoke (wants to be an AMF HD?).
Drive Train: 10 speed (5 x 2). Shifts like a Harley.
Other Stuff: Paint looks odd, tires need replacing.

Riding: Clutch slips a bit, but bike still goes like hell

After hearing the song "where is my mind" on my way home after dropping some down-money, I named this bike "Marla."

SSScottSS
04-11-2012, 07:42 PM
What are your plans for her? Shine her up and keep her stock, or turn her into a cafe bike?

-stew-
04-12-2012, 11:56 AM
I lurv me some CB! Buddy has one of those sitting at his house, his friend is working on it for some guy or some shit. Gorgeous two tone brown with a wind jammer. Neither of them knew it was a ten speed.

CannotPost
04-12-2012, 01:55 PM
I lurv me some CB! Buddy has one of those sitting at his house, his friend is working on it for some guy or some shit. Gorgeous two tone brown with a wind jammer. Neither of them knew it was a ten speed.

" Gorgeous two tone brown with a wind jammer"

LOL! wow!

Al
04-12-2012, 03:20 PM
A little more about "Marla":
She smokes...in the morning, after riding for a while, after a good thrashing.
She is modified...i'm not sure what is factory...one mirror is square and the other is round.
She has been around the block with waaaaay too many boys (owners).
She has spent some time in barns, hiding.


One feature that stands out on this bike is its 8 inch diameter headlight. I think Honda borrowed it from
an airplane because it lights up the road better than any vehicle I have ever been on.


What are your plans for her? Shine her up and keep her stock, or turn her
into a cafe bike?

I love the cafe style, but I think this bike is a bit too large to be a true cafe. Some of the cafe purists I have come
across will say "that bike is too big to be a cafe." I once replied, "that's what they said about your mother, but that
didn't stop her."

The picture in my mind is 80% cafe/20% Mad Max (monster bike?).

-I want to shorten the seat and eliminate any part of the frame past the rear shock mounts.
-I thing a 4-2-1 exhast would be an improvement with the muffler underneath the frame.
-Replace the "lunch box" brake light (it is huge) when I shorten the frame. I want a brake light that flickers when on.
-Straighter handlebars (but no clip ons)
-Make two saddle(?) boxes. Preferably wood with finger or dovetail joints. 8w x 16l x12h.
Figure out some removeable cantilever mount so that they look like they are "floating" near the rear tire.
-Weld a metal spike on it somewhere and put a doll's head on it.

I already bought a can of chalkboard pain for the tank and side covers. I thought it would be a good idea to take the bike down
to a place like "The Exit" in Chicago and leave a box of chalk on the seat and a little sign that says "use chalk on tank...have fun"
and keep a photo diary of what people write on Marla.

I want to try tuning this bike somehow. So far, I have found very few performance parts. The engine is sourced
from a cb750, so that should make things easier.

-stew-
04-12-2012, 07:46 PM
" Gorgeous two tone brown with a wind jammer"

LOL! wow!

I like earth tones.

Al
04-15-2012, 02:23 AM
Clutch removal:

I ground down a cheap, old socket and turned it into a lock nut socket. Aside from making the tool, this bike has been easy to work on.

http://www.brewcitymuscle.com/forum/attachment.php?attachmentid=7936&d=1334472754

The checklist for the slipping clutch:
-Clutch Cable - adjusted to factor specs. clutch still slips
-Spring Length - unsprung: middle of acceptable range
-Disk Thickness - not checked yet
-Disk Flatness - not checked yet
(time to dig out my granite surface plate...all 250 lbs of it!)

Could old oil (very black, maybe 20 years old) make a wet clutch slip?

Once the clutch has been dealt with, I have to clean the carbs.

The engine also has an intermittent habit of blowing blue smoke from the left exhaust pipe. A few CB750 people have said that this could be due to bad valve seals. The engine is due to have the valves shimmed and the cam cover gasket replaces.

Any other thoughts or suggestions?


I also wonder if I am the first person to remove some of these fasteners since 1982.

Al
05-13-2012, 09:54 PM
I put some new rubber on the bike.

Aside from the backlash in the drivetrain, nothing feels loose on this bike. Prior to the new tires, the bike felt a bit odd as I entered turns. I thought the steering or suspension bearings were worn somewhere. This bike is solid going down the road!

The clutch still slips. I changed the oil and scuffed up the plates, but the clutches don't grab after I pass 1/3 throttle. I'll order a new one tomorrow.

frank_zappa_is_dead
05-14-2012, 01:56 AM
Those old hondas go forever!

-stew-
05-14-2012, 07:09 AM
What do you mean by "backlash?" Are you talking about what I call the bucking feeling when you lay on the power? Only shaft bike I'm familiar with is the '83 Virago I had. And that when you laid onto it the whole bike rose up rather than the front end coming up. As far as I know this is characteristic of most shaft drive bikes.

Sent from my SCH-I500 using Tapatalk 2

Al
05-15-2012, 02:03 AM
I was snooping around on Google when I came across a CL add for a CB900c clutch in Sun Prairie. I emailed the guy and he contacted me back 20 minutes later. Two hours later, I bought a complete clutch for $40. The friction plates have far more material on them than mine, so this should work out.


What do you mean by "backlash?" Are you talking about what I call the bucking feeling when you lay on the power? Only shaft bike I'm familiar with is the '83 Virago I had. And that when you laid onto it the whole bike rose up rather than the front end coming up. As far as I know this is characteristic of most shaft drive bikes.

Sent from my SCH-I500 using Tapatalk 2

I'm talking about all of the play in the gears.

I heard that the rear raising when you gun it is called "jacking" or "jacking up/on." This bike does that.

Al
05-15-2012, 07:40 PM
I measured the thickness of the plates on the new clutch and they are only 0.001 off from mine.

I'm thinking that it is either the springs, the cable, or the plates are saturated with "friction reducers" due to the incorrect oil.

Al
05-16-2012, 09:16 PM
I drilled out some 1/4 inch washers and shimmed all of the springs, but this made the clutch too heavy to open. I removed half of the shims (3 of 6) and put it all back together.

This bike scoots!!!

The next step it to adjust the valves. I think cylinder #1 is a bit low on compression (egt is low).

Al
05-20-2012, 03:12 PM
Insight:
I thought my clutch was slipping because the engine would spin but the speedo did not change. When mounting the front wheel, I saw that the speedo links to the front wheel. My clutch was not slipping: I was spinning the rear tire.

More CB woes:

5th gear disengages when i give the bike throttle. It sounds like the dogs are worn. It can barely maintain speed in the gear.

When I jockey the throttle (such as when I try to power-wheelie from a roll (no clutch)), the bike feels odd afterwards. It seems as if the carbs get a bit messed up when I do this. Usually, the bike gradually returns to normal, but that takes afew miles. Any thoughts?

-stew-
05-20-2012, 04:05 PM
I doubt you were spinning the tire. Unless your rear tire is dangerously dry (or wet) and over inflated. Idk what you weigh, but I'm 225, and on my 120hp at the tire zrx, I couldnt blow the tire off it. It would either go, or go and pull the front tire up and go. And my 100 tire HP Ducati has never spun the tire. I really doubt your not running right, 75hp at the crank when it was new bike is blowin the tire off under hard acceleration.
Sent from my SCH-I500 using Tapatalk 2

Irish
05-20-2012, 04:39 PM
I doubt you were spinning the tire. Unless your rear tire is dangerously dry (or wet) and over inflated. Idk what you weigh, but I'm 225, and on my 120hp at the tire zrx, I couldnt blow the tire off it. It would either go, or go and pull the front tire up and go. And my 100 tire HP Ducati has never spun the tire. I really doubt your not running right, 75hp at the crank when it was new bike is blowin the tire off under hard acceleration.
Sent from my SCH-I500 using Tapatalk 2

Dump the clutch! I had an 89 Katana 1100 that'd roast the tire easily. The tire wasn't dry, wet, or over inflated.

Al
05-22-2012, 10:58 PM
I doubt you were spinning the tire. Unless your rear tire is dangerously dry

I was spinning my old tire before I replaced it. That tire was about 20 years old and would spin at 50% throttle and low revs in second gear. The lack of throttle-input, alond with the stationary speedo, led me to believe it was the clutch.

The new tire does not spin on asphalt; the bike wheelies. Road paint, manhole covers and broken asphalt are needed to spin the tire.

Shaft-drive power-wheelies (no clutching, just brakes) are a bit odd: the bike rears up and then the front does its thing.


About those carbs:
The guy I bought the bike from gave me a very detailed runthrough of how to clean the carbs. I'm going to get a look at them tonight. I'm also checking the valve clearances and maybe comp testing.


Anyone here ever lap their valves? I'm just curious at this point.



Idk what you weigh, but I'm 225

I'm not heavy by any means (I am down nearly 50 lbs from a little over a year ago).

On a similar subject, I beat some sort of Honda 600 on Saturday. I think the reason I won is because the rider was HUGE! I'm sure he was past the 300 mark.

Al
07-21-2012, 06:04 PM
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120624_230912.jpg

I tore the bike apart and found this. More pics on this later on. That shift for is missing about 3mm of its thickness.

GTSLOW
07-21-2012, 10:50 PM
Mad Max...one of the greatest movies ever!

http://atoast2toast.files.wordpress.com/2009/11/road-warrior-pic.jpg

Al
07-24-2012, 02:06 AM
Mad Max...one of the greatest movies ever!

http://atoast2toast.files.wordpress.com/2009/11/road-warrior-pic.jpg

I agree eleventy thousand percent!!!

One of my buddies has plans for a Mad Max party some time in August. He makes one hell of a Lord Humongous. He's a bit of a leather-fetishits-kinkster, so he'll walk around Milwaukee like that. BTW- you should see how his wife dresses!

Anyway, I need to weld some rebar spikes on my bike.

Al
09-17-2012, 12:56 AM
Those old hondas go forever!

You are correct when you say that it will "go forever," but this bike's engine has lost a significant amount of pressure in two of its cylinders.

I was riding through Brookfield about 3 weeks ago when my engine was running rough. I thought it was a fuel issue, such as air caught in the fuel line. I looked behind me and saw a thick grey cloud, which was coming out of my left exhaust pipe. I rode it straight home and started to perform a variety of tests on the engine and ignition. After checking the valve adjustments, I narrowed the problem down to either worn piston rings or poorly seating/damaged valves.

Time for a tear-down...then a rebuild.

Milwaukee Cycle salvage has a cb1100f engine. I'll start with that and bore it out to accept a set of Wiseco pistons.


PICS FROM THE PAST!!!

A hot evening in July:
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120623_221330.jpg

Back when I was dealing with 5th gear:
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120623_214733.jpg

I Could not get the engine in the frame, so I put the frame around the engine. A purist will cry at this.
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120705_214506.jpg

The Oil Dry bag was comfortable to sit on. I never really had to open it until I knocked a bottle of oil over:
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120617_003151.jpg

This is a pic of the day I broke down in Villa Park, IL. My stator was grounding and the bike was not charging.
http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20120812_163023.jpg


I have NO intentions of selling this bike at this point.

Al
09-18-2012, 07:36 PM
I bought the engine. I'll get to tearing Marla down later this week.

I'm looking for an engine shop to bore out my cylinders (possibly sleeve). Any recommendations?

Al
10-17-2012, 02:12 AM
Bump!

Again:
Can anyone recommend a shop for my engine work?

michelle
10-17-2012, 06:31 AM
Check with Mike (whiler?) at SouthEast Sales. I believe he works at the location that sells BMWs.

http://www.southeastsales.com/

loud91rs
10-18-2012, 10:04 AM
Competition cycle in butler will do the machine work. Had a cylinder bored by them on a dirt bike and they were super reasonable. It's cool to see somebody doing this. Most people would sell and move on.

Al
10-29-2012, 11:59 PM
An important detail about this motorcycle is that I've removed the parts, inspected the parts, reassembled them and managed to get the bike running again.

To me, that is something uncommon.


My current plans are to build a wheeled cart to put the bike on. I have some giant locking castor wheels which I picked up at the Buell liguidation sale. This will allow anyone to wheel it around the garage when they need to get to something. It will also help me by getting the bike an extra 18 inches off the ground.

The project is still on delay because I have yet to get my elbow (well, a second doc identified the issue as a spot about 3 inches down from my elbow) fixed. But I did replace my car yesterday...a "granny marquis." That civic of mine is falling apart.

Al
12-19-2012, 06:27 PM
I constructed a special dolly for Marla. The dolly holds on to the frame of the motorcycle, thus allowing me to remove the wheels, kickstand and center stand, as well as half of the frame, when I remove the engine. Also, it allows non-motorcycle-educated family members to move the bike in the garage.

The stand works, but I'll probably make a simpler version soon.

http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20121216_014437.jpg

This is my cb1100f engine. It needs an overhaul, but alone will make 25% more power than the 900.

I'm going to frankenstein the 900 and the 1100 with a set of Wiseco pistons and hopefully end up with an air-cooled, shaft-drive, 10-speed bastard motorcycle that scares 600s!

Let's go do wheelies in high range!

http://i1262.photobucket.com/albums/ii613/Al828282/IMG_20121006_025228.jpg

ZRXTURBO
01-16-2013, 11:28 PM
Al, Do you need another 1982 CB900?? I have one in storage, it was my stepfather's bike who passed away last year....

No title, needs work....

35,000 ish miles, full vetter fairing and bags. $500

Al
08-13-2013, 12:12 AM
Update:
Cylinder block has been bored to match a set of Wiseco pistons.
Competition Cycle did the machine work.
"Marla" has been disassembled to just the engine and the frame. Getting the engine out of the frame -or- frame off of the engine is the hardest part.