Author Topic: Kent restores a '70 CB750KO (Read 8969 times)

kbart1 · « **on:** April 24, 2014, 01:54:21 pm »

hey guiys

so I am moving my posts over to this section as I have now started the restoration phase. if this is NOT the right section to post progress and questions please let me know. I am starting with a fairly molested '70 KO that somebody did a mild chopper style back in the day. the bike has not run since at least 1990 when it was last registered. I have the bike running now but the clutch plates were stuck together so I pulled the clutch and everything is within specs and in good shape. putting the clutch back together now but here is my dilemma. when I removed the clutch plates/discs I neatly stacked them in order on the ground beside me. I stupidly turned and proceeded to knock them all over and mix them up. I have read the manual and looked at illustrations but am still not 100% sure I have it correct. here is how I placed the discs back onto the hub starting with the piece that is closest to the block that has the 4 posts that the clutch springs and lifter plate fit on. I started with what I will call the fiber disc. followed by the metal disc. alternating in that order. so I end up with a stack containing 7 fibre discs and 6 metal discs. the last item I have is the clutch "outer ring"? it looks like that goes on just behind the LAST fiber disc? does this sound correct I know this may sound confusing. would love to get this back together asap so I can fire it up and rip around the block to make sure the tranny shifts o.k. etc and once that's done I can start tearing it down for resto. attached are a couple pics of how I stacked this if it helps?

thanks a lot!
kent

kbart1 · « **Reply #1 on:** April 27, 2014, 10:08:06 am »

hello all

I am trying to figure out just where the keyed ignition switch was mounted on a '70 cb750? my data plate shows manuf. 1/70. was it up on the triple clamp near the gauges or somewhere else down on the frame. I seem to run across conflicting pictures.

thx a lot!
kent

754 · « **Reply #2 on:** April 27, 2014, 10:36:18 am »

Sitting on bike, it goes on left horizontal tank rail, up against the front. Reach down left lower edge of tank, to use Key.

Greggo · « **Reply #3 on:** April 27, 2014, 10:43:28 am »

Got any pictures of the chopper before you started?

kbart1 · « **Reply #4 on:** April 27, 2014, 03:09:40 pm »

here you go. pics! as requested.

thanks for the info 754! hope to have a few bits from Honda on tues. and button the clutch up. then test out the tranny before stripping it down.

thx
kent

754 · « **Reply #5 on:** April 27, 2014, 03:35:21 pm »

Let me know if you need a switch holder.

kbart1 · « **Reply #6 on:** April 27, 2014, 07:39:29 pm »

hey 754

yes I do need one. I can find the oem switch on e-bay but I can not find the associated brackets etc. to mount it. you got one? perhaps we can make a deal. pm me if you like.

thx
kent

kbart1 · « **Reply #7 on:** April 30, 2014, 08:06:32 pm »

hey 754

so these are the parts I bought on e-bay. so I believe all I need now is the actual center stand. anybody have a stand for a K0 they want to part with?

thx a lot!
Kent

krusty · « **Reply #8 on:** April 30, 2014, 08:26:14 pm »

Was that bike being run by PO without front brake?
Front wheel is back to front.

Johnie · « **Reply #9 on:** April 30, 2014, 08:36:10 pm »

Kent...one last thing you need besides the center stand is a cotter pin that goes in the end of the long tube you have in the picture. Just wanted to mention it. Sort of a safety device I think. Have it on my KO too.

kbart1 · « **Reply #10 on:** May 01, 2014, 11:44:09 am »

thanks guys

the PO had the bike sitting in his basement and I don't think he had ridin it. I advised him the wheel was on backwards and he just smiled. it had not been registered or insured since 1990 at least. this guy was a backyard hacker so now I am going thru correcting his stuff. its going to be a long project. with the model years and changes this is going to be a tough one sourcing parts I think. my CBX was a breeze compared to this one so far.

thx
kent

754 · « **Reply #11 on:** May 01, 2014, 03:17:48 pm »

I will look for a stand..

kbart1 · « **Reply #12 on:** May 21, 2014, 10:38:08 pm »

hey guys

progress made. got bike running and tooled around block to bang through all 5 gears and all seemed fine. bike is stripped down now for powder coat etc. couple questions and sure many more to come. I am going to sandblast the swing arm and powder coat. I don't want to strip out old bushings etc. if not nesc. I removed the outer "dust seals" and plastic covers. the rest of the stuff looks "pressed" into the swing arm and am hoping it will handle heat from powder coating? I am hoping to mask the bushings off and carry on. are there any parts inside the swing arm bushing area that would not like the heat of powder coating? any tips on removing the vin plate for blasting and powder coating of the frame AND re-attaching it? someone painted my motor black, I want to go back to stock color. anybody have any advise on engine enamel for painting? I like to use duplicolor engine enamel when possible. any idea what the finish on the bulk of the bolts on the frame are? motor mounts etc.? I would like to re-condition all the hardware as well when doing this resto. any advise is much appreciated!

thx a lot!
kent

Greggo · « **Reply #13 on:** May 22, 2014, 09:45:51 am »

Most bolts are clear zinc coated, but some are yellow zinc, or chrome. Duplicolor is a good choice for original looking finish on the motor, that's what I'm using on my sandcast.

SOHC4 Cafe Racer Fan · « **Reply #14 on:** May 22, 2014, 11:57:37 am »

You can drill out the rivets for the VIN plate and the re-rivet it back in with a Harbor Freight rivet gun.

kbart1 · « **Reply #15 on:** July 19, 2014, 12:48:40 pm »

well progress is being made and I will post some pics shortly. for now I have one issue that is killing me. how do you get all the little rubber pieces back onto the battery tray? I pulled them out to have the tray powder coated now I want to put them back. the 4 large ones on the tob were not a problem but the lower rubber mat that the battery sits on and the 4 round ones for the side of the batter are proving impossible to get back on. the rubber is soft however I cant get thye fittings through the holes in the tray?

several stab wounds and swear words later here I am. anybody have any thoughts?

??

thx
kent

Greggo · « **Reply #16 on:** July 19, 2014, 05:03:54 pm »

It's an exercise in finger abuse getting those little rubber bits on...

edwardmorris · « **Reply #17 on:** July 19, 2014, 08:05:50 pm »

What about the wintergreen treatment? Would that help soften them a little?? I've got my PC'd parts staring at me right now and the last thing I want is to scratch something or injure myself. I might just WG treat all the rubber I'm reusing and see how it goes..

754 · « **Reply #18 on:** July 20, 2014, 11:03:08 am »

Oil and a few screwdrivers..

HondaMan · « **Reply #19 on:** July 20, 2014, 11:55:08 am »

I soak the little nubs in xylol for about 30 minutes, make 'em real soft. Much easier to squeeze back in. Don't soak the whole thing, just the nubs that hold them in.

HondaMan · « **Reply #20 on:** July 20, 2014, 12:00:49 pm »

Quote from: krusty on April 30, 2014, 08:26:14 pm

Was that bike being run by PO without front brake?
Front wheel is back to front.

It was popular for a while to flip the front brake to the opposite side. When you have long forks, the over-center mass of the larger K0-K2 calipers adds "swing weight" to the steering. This is not a bad thing at speed, as it helps hold the straight line, but in parking lots it increases the work of turns, and with extended forks that's already a big deal.

The flip side: water collects against the pucks in the wet. This causes quite a delay when applying the brake in the wet. It also increases corrosion and dirt collection in the cavities around the pucks. The "other" bikes out there with the calipers behind the forks have either big troubles with this, or a different caliper design to try to cope with it. Today, in the interests of cheaper manufacture, most bikes just have the calipers mounted directly to the fork leg, behind the fork(s), but have a more intense maintenance schedule to keep them operational. (In "real" life, though, this usually fails, in my experience.

)

kbart1 · « **Reply #21 on:** July 23, 2014, 07:23:31 pm »

here's a question for you. why whenever I look up parts for my 1970 KO I can never find a '70 listed? even the Honda shop cant show a '70? my bikes vin tag says 1/70 for a production date so I have been using the 1969 model year to look up parts, sound correct? its as if the 1970 model year never existed?

thx
kent

Johnie · « **Reply #22 on:** July 23, 2014, 07:53:26 pm »

Yes, go with the 1969 CB750 and you will be fine. The 1970 is not part of the dealer listings.

kbart1 · « **Reply #23 on:** July 24, 2014, 11:39:13 am »

k thanks!

next question. I have my carb rack apart and the carbs apart ready to start going thru them. I have what looks like a white hard powder like substance in the bowls and the carbs, keep in mind this bike was last on the road in 1992. I have access to an ultrasonic cleaner but am wondering what is the solution people use with these machines and how they go about doing it? I am going to hit them with a spray carb cleaner to see what that does if anything as well. any thoughts would be much appreciated.

thx a lot!
kent

edwardmorris · « **Reply #24 on:** July 24, 2014, 11:45:06 am »

Check out my attempt here http://forums.sohc4.net/index.php?topic=126735.msg1542350#msg1542350

US cleaning didn't get the corrosion (white powder) out so I just wire wheeled what I could carefully.

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Author Topic: Kent restores a '70 CB750KO (Read 8969 times)