Author Topic: New Guy here  (Read 1266 times)

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Offline SurfinBird

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New Guy here
« on: April 13, 2011, 01:10:10 PM »
Hi guys, i've been reading this forum for a few weeks getting ready to start on a bike. I've found tons of great stuff, you guys are awesome. I figured it's time to actually join.

I haven't ridden a bike in about 20 years and have never worked on one. I have done, mostly, maintenance work on my older cars. I know a little (very) about cars, but i'm basically a novice.

Here's what I got, I'm picking up a '78 CB750 Supersport tonight. Doesn't start, it does kick over and runs for a few seconds off of quickstart. The tank has rust, clutch cable needs replacing, new battery and possibly a new ignition. I think I can do most of that myself, may need help with the rust, but, I got a paint shop that can do it if I can't make it work myself. It was last in regular use in 2003.

I got this thing mostly to work on for fun (divorced, kids only half the time and want to stay out of trouble). I'd be really happy if I can get this thing running and use it as a commuter a couple days a week (gas prices are what got me thinking of a bike)

Here's what I want to do, please let me know what else I should do. Just looking to get it running and safe. I'll worry about the looks once I get it running.

- Pull and clean the carbs (youtube has a great video on cleaning bike carbs)
- Replace the spark plugs
- New plug wires?
- New fuel lines
- Rebuild the master brake cylinder (youtube again)
- New oil filter
- Oil change
- New paper element in the airbox (thinking ditching the airbox and going K&N, thoughts?)
- Check tires (replace if they look dodgy)
- Replace brake shoes if needed

I don't what to touch the engine or calipers if I don't have to, i'm sure I will eventually. I figure once I get it running lots of issues will rear their head.

Here's the early questions:

I plan to try electrolysis and a bunch of wood screws and washers for the rust. Should I try the Kreem kit, POR 15 or take it to the paint shop once I got it as far as I can?

Should I get a carb rebuild kit and swap out the gaskets and jets?

Any advice is appreciated, and thanks in advance.I will post picks once it's in my garage.

p.s. anyone else having a hard time with reading the verification letters?

Offline flybox1

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Re: New Guy here
« Reply #1 on: April 13, 2011, 01:36:37 PM »
welcome to the madness  :o  8)

getchaself a shop manual and clymer book.  the manual you can download from this site.
good page by page details on how to do what we do....
to do's:
if your bike is stock, keep it that way until you get it tuned and running.  then, if you must  ::), make your performance changes.

battery...preferrably new.
3k mi service, which includes valves, timing, new(clean) stock air filter, carb cleaning(not rejetting), cam chain adjustment, plugs, wires if needed, and oil/filter change.
you can get a carb rebuild kit, but you might do better by reusing the brass parts from your bike, and poaching the orings from the kits or source individual orings.  just clean the carbs really well, and keep it stock for now.

your brakes are what keep you alive, so dont skip digging into the caliper to see if the seal, piston, and(probably) the brake fluidneed changing.  maybe a master cylinder rebuild.

try THE WORKS toilet bowl cleaner for the rust in your tank first, then you can decide if it needs more rust treatment..
post pics if you got 'em!
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
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Offline Bob Wessner

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Re: New Guy here
« Reply #2 on: April 13, 2011, 01:45:54 PM »
Welcome. You will post pics immediately after you pick it up.. right?  ;)

Quote
and a bunch of wood screws and washers for the rust.

I went this route 5-6 years ago cleaning mine. They are a pain to get out of the tank afterward. Consider several short lengths of sash chain instead.
We'll all be someone else's PO some day.

KingCustomCycles.com

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Re: New Guy here
« Reply #3 on: April 13, 2011, 01:58:43 PM »
Welcome, I sure get the divorce and wanting to stay out of trouble thing.  That was one of the reasons I started my shop.  Motorcycles are a great way to do just that!

Offline TwoTired

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Re: New Guy here
« Reply #4 on: April 13, 2011, 02:25:56 PM »
Here's what I got, I'm picking up a '78 CB750 Supersport tonight. Doesn't start, it does kick over and runs for a few seconds off ...
 
- Pull and clean the carbs (youtube has a great video on cleaning bike carbs)
This may be required.  But, I pull off the bowls first to see if it is really needed.  Having said that, it's likely that the pilot jets are plugged, and will have to be yanked from the carb bodies to properly clear them.  The ease of bench work is balanced with the ease of not removing/reinstalling the carb bank.  If you chose to remove them, plan on getting new rubber boots both fore and aft of the carbs.

- Replace the spark plugs
Sure, why not?  NGK D8EA

- New plug wires?
The stock plug wires are molded into the coils.  Unless you find a specific problem, treat the wires gingerly to avoid cracking.   Measure the plug cap resistance (they unscrew)  S/B 5000 ohms +/- 10%.

- New fuel lines 
You have a reason for this?  Then get the correct 5.5mm line.

- Rebuild the master brake cylinder (youtube again)
Is there a reason this is necessary?  Is it beyond a simple brake fluid change?  Anyway, you have two; one front, one rear. 

- New oil filter
- Oil change
Certainly

- New paper element in the airbox (thinking ditching the airbox and going K&N, thoughts?)
Fine... if you want to learn a whole lot about how carbs work, have a test track or access to a dynomometer, in order to discover what jetting and carb readjustments will compensate for the 4 individual filter change.  Otherwise, put a K&N element in the stock filter box and go ride it.

I don't what to touch the engine or calipers if I don't have to, i'm sure I will eventually. I figure once I get it running lots of issues will rear their head.
This particular 750 model has a bad reputation for wearing valve guides prematurely.  I would do a compression check or a leak down test on any new acquisition that isn't running.
You can only avoid the calipers if they aren't dragging on the rotor.  Do a fluid change, at least.

I plan to try electrolysis and a bunch of wood screws and washers for the rust. Should I try the Kreem kit, POR 15 or take it to the paint shop once I got it as far as I can?
I favor the electrolysis method.  You shouldn't need screws.  This tank is a real pain because of the sunken well at the top.  It makes it really difficult to completely empty contents, and get cleaning solution in the air pocket it creates.  IMO the internal surface needs to be etched after de-rusting before a coating goes on.  If you trust a shop to do the work correctly, it will save you a big frustration.  But, get a guarantee in writing.  Kreem will pool at the low points and you are supposed to drain out the excess after coating.  It's a challenge to keep the coat thin so it can properly cure.  It is not catalysed.  So, it needs thorough air drying to for it to harden properly.  If you put in gas before it completely cures, the coating will fail.

Should I get a carb rebuild kit and swap out the gaskets and jets?
No just clean the metal bits you have.
As for the rubber gaskets, it depends on when they were last replaced or how hard they have gotten.  If the bowl gasket reseals, you are good.  If you separate the carbs from the bank, then there are more bits to replace.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Old Scrambler

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Re: New Guy here
« Reply #5 on: April 13, 2011, 03:22:34 PM »
All of above is +1..........fix the rust in the tank before you tackle the carbs. Read and study before you grab a wrench.  When the bike runs on its own..........it may take a few miles to loosen up and self-clean the carbs with a little SeaFoam in the tank of fresh gas.  Then do the compression and leak down tests. 
Dennis in Wisconsin
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Offline SurfinBird

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Re: New Guy here
« Reply #6 on: April 13, 2011, 03:48:54 PM »
flybox1:
Got the Clymers, one of the 1st things I ordered. Battery, YES, I forgot to mention the battery was dead. I read about "the Works" somewhere else. I'll give that a shot first.

Bob Wessner:
Will do on the sash chain. Pics will be posted ASAP. Picking it up in a few hours. It's like waiting for xmas morning.

KingCustomCycles.com:
Getting in trouble can be fun, but, i think this project will cost me less in stress and $ in the long run.

TwoTired:
Wow, thanks. Looks like my free time is spoken for, at least for the next several weeks. I'm going to print this out and use it as a checklist.

Old Scrambler:
I've been studying these forums and downloaded a few manuals. I plan to measure twicw and cut once with this whole thing.

Thanks guys. This is exactly what I was hoping for. I knew I came to the right place.