Still looking but wanted to join...

Posted: Sun Jun 11, 2023 10:50 pm

Looking for a CB900C (may have found one) but wanted to join for the info that I am sure is here.

I rode a 900c as a teen (bike belonged to my boss and he let me ride it on occasion) and am at a point were I can have more than one bike (Just totaled a Goldwing, looking for another one of those as well), so figured why not look around for both.

Have a decent looking '81 I am going to look at tomorrow, so may be an owner by the time most read this.

Posted: Mon Jun 12, 2023 7:22 am

Welcome to the site blupupher ... Smile

Posted: Mon Jun 12, 2023 6:54 pm

Welcome to here.

Good luck finding a ride.

Posted: Fri Jun 16, 2023 7:52 pm

Thanks.

Picked up an '81 CB900C with almost 25,000 miles on it Monday.

Listing had it as a running bike. Got there and it was "running" but missing on at least 1 cylinder and maybe 2. So it did run, but poorly.
I had a video of it running well on the listing, but it had sat for over a month since last started.

Bike in person was a lot rougher than pics showed, but ended up getting it anyway since I drove 180 miles to go get it.
I ended up paying $2000 for it (+ about $150 in gas and trailer rental fees), and am having a little buyers remorse at the moment.

Bike had been sitting for unknown time, but last registration was 2004.
Guy I got it from cleaned the carbs, changed the plugs, and rebuilt the brakes (both masters and all 3 calipers) and brake fluid changed.
Needs new tires. Tank has rust inside and has some repairs on the left side. Seat has a few tears in it. Brake lever is broken/bent. Some screws/nuts missing (both nuts on bottom of levers are missing, only 1 screw in airbox cover), rear suspension leaks slowly.
It has a 4 into 4 exhaust, but not sure if it is stock. Centerstand or sidestand drag when making a left turn. Seems like the left side exhaust is low?

I thought it was the coils at first, but then realized it was cylinder 1 and 3 that were not heating up (IR thermometer showed 2/4 warming up quick, 1 was a touch warmer than before starting, and 3 did not go up at all ).
Checked spark and the plugs in 1 and 3 had no spark and 2/4 were weak spark, plugs were very sooty and dark (but gapped correctly).
Got some new D9EA plugs and runs on all 4 cylinders now. Still an occasional backfire though.
I have changed all the fluids (the sub transmission was a pain, the exhaust was up against the drain bolt, which is part of why I wonder if it is a stock 4 to 4 unit).

I from reading here, I know I need to check the valve clearances, just ordered the Motion Pro valve tool, need to figure out best place to buy shims. Will check compression once that is done.
Thinking of rebuilding rear shocks (need to figure out what I should replace while they are apart).
I have ordered some GL1500 coils off e-bay, and will be doing the relay mod to power them. Wondering if I can use the GL1500 cables on the CB900? Don't care about looks as much as does it work?

Tires are on my to do list, but they hold air and roll, I want to get the bike running better before I do that (tires are old and cracked, but fine for me for a 20 mph test ride up and down the street, will replace before I take it "on the road").

I am also reading about a cam chain tensioner? I need to adjust, need to get that figured out as well.

I did get a FSM and a Clyemer manual with it, so I have the resources to do stuff, just not the knowledge and tools at the moment.

Back to reading the forums to figure stuff out.

Posted: Sat Jun 17, 2023 7:25 am

It 'looks' decent from here . Wink

You have to expect a 42 year old machine to have a few things in need .

Posted: Mon Jun 19, 2023 11:00 pm

Cleaning these carbs is not a quick and easy thing, and even those that are good at it may wind up doing it over.

Yeah, it looks good from across the garage over the phone. Twisted Evil