Author Topic: Senior project for high school - 78 CB750K  (Read 175116 times)

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Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #850 on: April 11, 2015, 04:56:07 AM »
No, we don't have an oil cooler adaptor plate.

Yeah, I hate to drain all the oil out of her but I think that's the prudent next step...to drain it and try test fitting all of this again without the spring to make sure everything is going in as it should.  Then, we'll re-assemble and put some oil back in.

Raphi and Martin,
Thank you both for your advice. :)
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline seanbarney41

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Re: Senior project for high school - 78 CB750K
« Reply #851 on: April 11, 2015, 05:28:21 AM »
No need to drain the tank or the pan.  You won't even lose a full quart.
If it works good, it looks good...

Offline Johnie

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Re: Senior project for high school - 78 CB750K
« Reply #852 on: April 11, 2015, 06:57:29 AM »
Just a thought...are you using OEM filter and gasket? Some guys were having trouble with Emgo and aftermarket filters having to narrow a filter housing gasket. They put the used OEM gasket back on and that solved the leaking from under the filter. Also do a good check of the filter housing for cracks. I like the idea to try the filter bolt with the housing off to see how easily it goes into the threads. Hoping the PO did not cross thread that area. It should not take much torque to seal that OEM gasket and no sealant should be needed.
« Last Edit: April 11, 2015, 07:02:22 AM by Johnie »
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline NobleHops

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Re: Senior project for high school - 78 CB750K
« Reply #853 on: April 11, 2015, 07:29:29 AM »
Ron,

Try this - remove the housing and invert it, insert the bolt and the spring and oring and filter and then compress the filter against the spring, see if it's compressing smoothly. I think the filter might be hanging up on the bolt.
Nils Menten * Tucson, Arizona, USA

I have a motorcycle problem.

My build thread: NobleHops makes a 400F pretty for his wife: http://forums.sohc4.net/index.php?topic=131210.0

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #854 on: April 11, 2015, 08:20:12 AM »
Ron,

Try this - remove the housing and invert it, insert the bolt and the spring and oring and filter and then compress the filter against the spring, see if it's compressing smoothly. I think the filter might be hanging up on the bolt.

That's exactly what was happening.   We removed everything and then just screwed the bolt in without even the housing on. It went smoothly all the way into the end of the threads. So at that point, we knew the problem was not the bolt or where the bolt goes into the engine.

 The filter is one I purchased from Amazon. The rubber gaskets on the top and bottom of it or very, very, very snug against the bolt.   We reassembled everything and then gently inserted it and started to tighten. At one point, it felt like we had stripped the bolt but we realized it was just the rubber grommet finally releasing its grip and letting the assembly finish its job of tightening against the housing. 
« Last Edit: April 11, 2015, 09:38:28 AM by Restoration Fan »
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline NobleHops

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Re: Senior project for high school - 78 CB750K
« Reply #855 on: April 11, 2015, 11:04:08 AM »
Cool! Onward! Fire this beauty up!
Nils Menten * Tucson, Arizona, USA

I have a motorcycle problem.

My build thread: NobleHops makes a 400F pretty for his wife: http://forums.sohc4.net/index.php?topic=131210.0

Offline Stev-o

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Re: Senior project for high school - 78 CB750K
« Reply #856 on: April 11, 2015, 11:21:43 AM »
Cool! Onward! Fire this beauty up!

+1  We are impatiently waiting!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline SOHC4 Cafe Racer Fan

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Re: Senior project for high school - 78 CB750K
« Reply #857 on: April 11, 2015, 12:59:28 PM »
Alright already!!  Ron and Logan just don't want to compete in this month's BOTM!
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
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"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
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2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
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Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #858 on: April 11, 2015, 01:54:57 PM »
 :D  Well, we're impatiently waiting too.  You have to remember that at least one of us is an idiot.

We tried to bleed the front brakes but, although we hear air coming out, there's no fluid coming down out of the line.  (And I mean we pumped on it for 3 or 4 minutes.)  Makes me think we might not have put everything back together perfectly in there so that might have to come back off and try that again.  We'll see.  For now, we decided to punt on that one and see if we could get her to fire up.

After a couple of tries, we finally got the carbs mounted...ended up using the ratchet strap method and it sure does make things easier.

Know what else would be easier after that?  If you actually go ahead and connect the throttle and choke cables BEFORE putting the air box on.  Yeah...we didn't do that.

And after the hour and and a half that it took us to get the air box mounted and on the carbs, we REALLY don't want to take it back off. 

I gave Logan a break for a few hours to go play Ultimate Frisbee with his buddies while I run to Home Depot and purchase a really long set of needle nose pliers to try & grab the barrel of the throttle cable that needs to snake underneath the system.  If we are able to grab it that way, we can hopefully avoid taking the airbox off.

But this IS Stella after all.  I'm betting the airbox gets pulled.



Once that happens though.  We're putting some gas in the tank and going to try & fire it up.  Should be sometime later this evening and we're going to video it.  I'll put it on YouTube, assuming it doesn't sling a rod out of the engine housing and kill one or both of us.  :P

« Last Edit: April 11, 2015, 01:59:39 PM by Restoration Fan »
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #859 on: April 11, 2015, 06:51:50 PM »
*sigh* So we haven't started it yet.  Ended up taking the air box back off and mounted up the cables.  This time, it only took a few minutes to re-mount the air box.  So then we went through the process of finishing up other things. 

It took us much longer to get the spark plugs back in than we thought it would.  #'s 2 and 3 are a b**ch!  Finally got them in and I had even sent Logan to go buy 2 gallons of Ethanol-free gas (we're fortunate to have a station with Ethanol-free gas about a mile away from our house).

So...at this point, the only thing left to do is hook up the fuel line and run the other three carb overflow lines.  That happens tomorrow.....and then we turn the key.  Man, it's going to be hard to sleep tonight.

I do have a question though:  when we twist the throttle, it opens fine but it doesn't spring back.  I thought the pull cable was supposed to do that.  Is there some type of adjustment that we need to make or something so that it snaps back?

Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline NobleHops

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Re: Senior project for high school - 78 CB750K
« Reply #860 on: April 11, 2015, 07:16:51 PM »
:D  Well, we're impatiently waiting too.  You have to remember that at least one of us is an idiot.

We tried to bleed the front brakes but, although we hear air coming out, there's no fluid coming down out of the line.  (And I mean we pumped on it for 3 or 4 minutes.)  Makes me think we might not have put everything back together perfectly in there so that might have to come back off and try that again.  We'll see...

Ron, the first fill of an empty brake system can definitely be a minor PITA. Here are a few things to try:

For starters, take one of those thin stretchy supermarket bags, poke your finger through it, then stretch that over the master cylinder and make a containment vessel for the fluid. Loosen the MC clamp bolts and rotate it so the reservoir is the highest point and level.

Next, loosen both bleed screws 360 degrees and push a couple of feet of tubing on them, to a catch jar. I like peanut butter jars with plastic tops. Poke a hole with an awl just big enough to get the tubing through, and a teeny one for a vent. Side note - two wraps of teflon tape on the bleed screws will help a lot when you are really bleeding the last of the air bubbles later.

Next, fill the MC, leave the diaphragm off and put the cap on a little loosely.

Next, don't be so delicate with the lever. Fan it several times fast, let it snap back in between. You're trying to jar the air pocket in the MC and the upper banjo to let fluid displace it. WHAP WHAP WHAP WHAP. Pull the MC cover off, see if the level went down. Add more fluid, repeat. WHAP WHAP WHAP WHAP. Etc. Keep an eye on the peanut butter jar - before long fluid will start to run down the tubing. Bravo, progress.

Once you get the big mass of air out of the MC and the upper banjo, you will feel that it is starting to pump fluid. Good. Now fill the MC to the brim, cap it loosely again without the diaphragm and just leave it for a while, keep an eye on it. Gravity will prime it most of the way from here. Once you get to this stage, take the handle of a screwdriver and TAP TAP TAP along the brake lines, the splitter, and the upper banjo, to dislodge air bubbles in the lines.

When you've got fluid coming out of both bleed screws, close one and do a few bleed cycles of each calipers. Nevermind the MightyVac, just pump, open the bleed screw during the pump stroke, close it just before the end of the pump stroke. Repeat for the other side.

Got most of the air out? Great. Top up the MC just to the upper fill line this time, cap it, and then pull the brake lever about halfway to the grip, strap or tape it there, and leave it overnight. Repeat the bleed the next day, strap it again overnight, and you should be good to go.

The last bit is crucial. You can pump a pint of fluid through bled calipers and still have a spongy lever. Strapping it halfway lets the tiny bubbles that are in the fluid make their way up to the atmosphere (the reservoir) through the return orifice in the MC. Tapping the lines and splitter while the lever is strapped is a good idea too.

Good luck with starting it tonight. Nervy stuff, I remember each one after a big project. Have the fire extinguisher nearby, just to ensure you don't need it :-).

Nils Menten * Tucson, Arizona, USA

I have a motorcycle problem.

My build thread: NobleHops makes a 400F pretty for his wife: http://forums.sohc4.net/index.php?topic=131210.0

Offline NobleHops

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Re: Senior project for high school - 78 CB750K
« Reply #861 on: April 11, 2015, 07:26:30 PM »

It took us much longer to get the spark plugs back in than we thought it would.  #'s 2 and 3 are a b**ch! 

The best tool I know of to put those center plugs in is that oddball sparkplug tool that Honda tucked in the toolkit. I've got a half-dozen different sparkplug sockets, that works the best. It holds the plug lightly, you can rotate it backwards till you feel the threads align and catch, and you can rotate it with your fingers to insert, then give it that last 1/4 turn with a screwdriver for leverage through the hole to crush the hollow washer.

A light smear of antiseize on plug threads is always a good idea.

Nils Menten * Tucson, Arizona, USA

I have a motorcycle problem.

My build thread: NobleHops makes a 400F pretty for his wife: http://forums.sohc4.net/index.php?topic=131210.0

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #862 on: April 11, 2015, 07:30:04 PM »
 A couple of lessons learned over the past few days:
1.  A Sylvania H6024 sealed-beam headlight is the same one as used in our Hondas and you can get them at most auto part stores.  If you don't remember the exact model number when you're at the store, tell them you need a headlight for a Jeep CJ-7.  It's that bulb.


2.  Soaking carb boots in Wintergreen oil really does work.  I used about this much oil along with 2 cups of water.  I put them in a pan and put them on medium/low heat for about 4 minutes and then removed them onto paper towels.  They didn't swell but they were (and still are) pliable and you can work with them.


3. When mounting carbs to the bike, use a ratcheting tie-down strap wrapped around the carbs and the front of the frame.  It not only helps to pull them into the carb boots properly, it holds them in place afterwards while you tighten the clamps around the boots.

4.  Attach the throttle cables and choke cable to the carburetor rack BEFORE you mount the air box.

5.  When mounting the air box, push the box in so that the flexible rubber boots in the air box are mostly aligned at the bottom of the 4 carb holes.  Then, lift the air box up and then gently but with some force, push it forward to try and get all 4 boots onto the holes at the same time.  Once you get all four of them started, gently pull the box back.  Remembering that the flexible rubber boots in the air box move in and out, as you pull the box back, make sure to pull each of those boots so that they're staying on the carb and only the air box is moving back into position to be mounted.

Hope these help someone else.  Seems like we learned them the very hard way. :)

« Last Edit: April 11, 2015, 07:32:47 PM by Restoration Fan »
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #863 on: April 11, 2015, 07:33:58 PM »
Ron, the first fill of an empty brake system can definitely be a minor PITA. Here are a few things to try:

Awesome explanation!  Thank you.  We'll give that a shot tomorrow!
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline madmtnmotors

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Re: Senior project for high school - 78 CB750K
« Reply #864 on: April 11, 2015, 07:53:52 PM »
I do have a question though:  when we twist the throttle, it opens fine but it doesn't spring back.  I thought the pull cable was supposed to do that.  Is there some type of adjustment that we need to make or something so that it snaps back?

Looking at the picts of your carbs, did you return part number 16036-405-004 to it's rightful place?


TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

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Offline Stev-o

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Re: Senior project for high school - 78 CB750K
« Reply #865 on: April 11, 2015, 08:10:37 PM »
A couple of lessons learned over the past few days:
1.  A Sylvania H6024 sealed-beam headlight is the same one as used in our Hondas and you can get them at most auto part stores.  If you don't remember the exact model number when you're at the store, tell them you need a headlight for a Jeep CJ-7.  It's that bulb.


2.  Soaking carb boots in Wintergreen oil really does work.  I used about this much oil along with 2 cups of water.  I put them in a pan and put them on medium/low heat for about 4 minutes and then removed them onto paper towels.  They didn't swell but they were (and still are) pliable and you can work with them.


3. When mounting carbs to the bike, use a ratcheting tie-down strap wrapped around the carbs and the front of the frame.  It not only helps to pull them into the carb boots properly, it holds them in place afterwards while you tighten the clamps around the boots.

4.  Attach the throttle cables and choke cable to the carburetor rack BEFORE you mount the air box.

5.  When mounting the air box, push the box in so that the flexible rubber boots in the air box are mostly aligned at the bottom of the 4 carb holes.  Then, lift the air box up and then gently but with some force, push it forward to try and get all 4 boots onto the holes at the same time.  Once you get all four of them started, gently pull the box back.  Remembering that the flexible rubber boots in the air box move in and out, as you pull the box back, make sure to pull each of those boots so that they're staying on the carb and only the air box is moving back into position to be mounted.



5. A 6" length of tubing attached to the top of the spark plugs makes it much easier to install the plugs in cylinders #2 & 3.  The plug holes are slightly angled too. 
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline martin_uk

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Re: Senior project for high school - 78 CB750K
« Reply #866 on: April 12, 2015, 02:31:07 AM »
On brake bleeding, I have had good results by using a large medical syringe to suck fluid out of caliper bleed nipple.

Used a female bullet connector insulator to connect to nipple.

May need a few squeezes on master cylinder lever to dislodge air trapped around piston.

You can see it coming out of return hole, but be careful of fluid squirting back as it will remove paint. :'(
« Last Edit: April 13, 2015, 04:39:58 AM by martin_uk »
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #867 on: April 16, 2015, 04:57:28 PM »
Our starter turns but it sounds as if it's stripping the gears when you hit the starter button, rather than engaging and turning the engine over.  Is there a bendix inside this starter that might have gone bad and that's the sound we're hearing?  Because we took the stator cover off and the teeth on the gear that goes between the fly wheel and the starter motor gear seems fine.  The end of a few teeth on the starter gear look a bit sketchy but not enough that it should make the sound it's making.

Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline evanphi

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Re: Senior project for high school - 78 CB750K
« Reply #868 on: April 16, 2015, 05:07:29 PM »
Our starter turns but it sounds as if it's stripping the gears when you hit the starter button, rather than engaging and turning the engine over.  Is there a bendix inside this starter that might have gone bad and that's the sound we're hearing?  Because we took the stator cover off and the teeth on the gear that goes between the fly wheel and the starter motor gear seems fine.  The end of a few teeth on the starter gear look a bit sketchy but not enough that it should make the sound it's making.



Is the washer there? (Part #3)

--Evan

1975 CB750K "Rhonda"
Delkevic Stainless 4-1 Header, Cone Engineering 18" Quiet Core Reverse Cone, K&N Filter in Drilled Airbox
K5 Crankcase/Frame, K4 Head and Cylinders, K1 Carbs (42;120;1 Turn)

She's a mix-matched (former) basket case, but she's mine.

CB750 Shop Manual (all years), searchable text PDF
Calculating the correct input circumference for digital speedometers connected to the original speedometer drive

Offline mystic_1

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Re: Senior project for high school - 78 CB750K
« Reply #869 on: April 16, 2015, 05:14:38 PM »
You can also consider pulling the starter part way out or all the way out, and running it briefly to see if the sound is coming from the starter itself, or from the rest of the system.

mystic_1
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Offline AintNoEasyWay

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Re: Senior project for high school - 78 CB750K
« Reply #870 on: April 16, 2015, 06:18:08 PM »
Ron, any chance you could post a video of the sound?

Offline edwardmorris

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Re: Senior project for high school - 78 CB750K
« Reply #871 on: April 16, 2015, 06:36:43 PM »
Long shot but could it be the starter clutch?

Offline Restoration Fan

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Re: Senior project for high school - 78 CB750K
« Reply #872 on: April 16, 2015, 07:16:43 PM »
This first one was from last Saturday.

This one is as of a few minutes ago.

It does have the washer in there.  I removed the connecting gear and the washer and pin and replaced them back in yesterday but it's still doing it. 
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline madmtnmotors

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Re: Senior project for high school - 78 CB750K
« Reply #873 on: April 16, 2015, 08:13:18 PM »
My money is on the starter clutch. Mine will do it intermittently (60,000 miles) but will usually "catch" on the next try. Bad part is you have to pull the alternator rotor off the crank to get to it. I don't recall, have you pulled the alternator rotor on this build?
TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

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Offline Stev-o

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Re: Senior project for high school - 78 CB750K
« Reply #874 on: April 16, 2015, 08:22:38 PM »
My money is on the starter clutch.


I'm betting with Wilbur. I too had a K7 that did it, but only after 4-5 seconds of cranking.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........