Author Topic: CB750 K1 project  (Read 50598 times)

0 Members and 1 Guest are viewing this topic.

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #175 on: May 08, 2014, 07:26:40 PM »
Oil pump is in.



Engine is painted and curing as best I can with what I have available. Monitoring temps and trying to keep it fairly low and even. A few small spots bubbled up on the cases, probably from not cleaning well enough. The top end looks fine but that was all blasted and more thoroughly cleaned. I'll touch up as best I can.



Testing alternator to get ready for reinstalling that. Spec is .2 ohms... I have two stators, one measures .5 ohms, the other .6 ohms. The .5 ohms came out of the bike and is closer to spec, never had any issues with charging. I think I'll put new bullet connectors on and use that one. Will replace the rough semi-melted looking ones on the small engine harness too. Not sure if there's an acceptable limit on stator resistance, but if it's a problem I suppose it's easy enough to change if need be. I'd imagine this is another part NLA and as long as it charges to some extent I'd rather not have another oil pump fiasco. I may end up getting that lighter rotor higher output setup from the dude in NH anyhow.

Getting very close to putting this in the frame!   ;D Just a few odds and ends, adjust valves, install covers and whatnot and then get creative with straps to slide it in. Not sure if I want to hang it from overhead or support on jack stands. I'll figure something out. Frame will get padding on it and hopefully between that and attempting to cure the engine paint I won't have to touch anything up.

Offline calj737

  • Really Old Timer ...
  • *******
  • Posts: 21,009
  • I refuse...
Re: CB750 K1 project
« Reply #176 on: May 08, 2014, 07:30:31 PM »
Rick's rebuilds stators if you end up needing to go that route.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline rtbmrgl

  • Expert
  • ****
  • Posts: 795
  • Got Points! Roseville, Ca
Re: CB750 K1 project
« Reply #177 on: May 08, 2014, 08:35:22 PM »

Engine is painted and curing as best I can with what I have available. Monitoring temps and trying to keep it fairly low and even. A few small spots bubbled up on the cases, probably from not cleaning well enough. The top end looks fine but that was all blasted and more thoroughly cleaned. I'll touch up as best I can.



What paint did you use?
thanks, Mark
Roseville, Ca

Got Points!

1973 CB500 back yard find 1243 orig mi,  http://forums.sohc4.net/index.php?topic=124285.0
1976 CB750 Restoring,        http://forums.sohc4.net/index.php?topic=132997

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #178 on: May 09, 2014, 05:38:14 AM »
What paint did you use?

Duplicolor DE1615 Aluminum over Duplicolor engine primer. There was also a 1650 aluminum and I couldn't determine the difference, from a quick search here it looked like 1615 was more commonly used. Might be true, might not be. The paint went on more "runny" and I had to be more careful with it than when using Duplicolor Gloss Black or Ford Blue engine paint. This was more of a pain to paint than a typical cast iron engine block where the paint goes on smooth and easy, sticks well, and quickly dries tough as a rock.

Offline rtbmrgl

  • Expert
  • ****
  • Posts: 795
  • Got Points! Roseville, Ca
Re: CB750 K1 project
« Reply #179 on: May 09, 2014, 10:00:20 AM »
What paint did you use?

Duplicolor DE1615 Aluminum over Duplicolor engine primer. There was also a 1650 aluminum and I couldn't determine the difference, from a quick search here it looked like 1615 was more commonly used. Might be true, might not be. The paint went on more "runny" and I had to be more careful with it than when using Duplicolor Gloss Black or Ford Blue engine paint. This was more of a pain to paint than a typical cast iron engine block where the paint goes on smooth and easy, sticks well, and quickly dries tough as a rock.
I used the same but also topped with there high heat clear.  Ive noticed on my 750 the cyld head has turned slightly yellow, but on my 500 it didn't yellow. I thought it was from running to lean, but the 750 is running on the rich side.
Nice project looking forward to see it completed.
thanks, Mark
Roseville, Ca

Got Points!

1973 CB500 back yard find 1243 orig mi,  http://forums.sohc4.net/index.php?topic=124285.0
1976 CB750 Restoring,        http://forums.sohc4.net/index.php?topic=132997

Offline Terry in Australia

  • Really Old Timer ...
  • *******
  • Posts: 33,281
  • So, what do ya wanna talk about today?
Re: CB750 K1 project
« Reply #180 on: May 09, 2014, 05:47:36 PM »
Looking good mate, and I love your heater, I could use one here now, if I had any room in my garage for one! Cheers, Terry. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #181 on: May 24, 2014, 03:11:37 PM »
Finally got some time to work on this and earned a second pair of hands. Dropped right in by hand took maybe 10 mins and only got hung up once then we found the right angle.



Now lots of little things but nearing the end.

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #182 on: May 25, 2014, 05:39:35 PM »
Getting ready to fire the engine and wiring is not looking good. Have a few extra wires in the repop harness (CB750supply?) and some colors don't seem to match. Key on and horn blows, neutral light on, no oil pressure light. Not very helpful. I guess it's figure out the wiring nightmare tonight.

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #183 on: May 26, 2014, 05:20:48 PM »
Got it together.





Oil pressure light issue was a bad sender. I may have overtightened the small bolt that holds the wire on. Verified oil out the main gallery and top end looks oily through the tappet covers so good enough for now. Spent a lot of time on that one as I was paranoid about oil pressure. Any trick to getting the oil pressure sender out without removing the cam tensioner?

Seems to run fairly well. Gotta get the idle dialed in and carbs synced. I didn't rebuild the carbs, just popped the bowls and sprayed out the passages I could get to. Hope I don't end up regretting that. Had an occasional stumble when accelerating lightly to moderately but cleared up each time. I'll figure it out...

Biggest problem is clutch. It seems to have a lot of slack and had to adjust it way out. Clutch lever fully pulled (at the clutch cover, arm bottoms on the seal/cover) and it still drags. Seems to have a LOT of slack from fully released until it starts pushing on the basket. I have a feeling this is a problem I created. I put the cover on and had the center bolt/actuator clocked wrong for the arm so had to pull the cover off again. Before this it seemed to have a normal amount of slack. Cover didn't want to pop off (Gasgacinch is good stuff) so I put pressure on the clutch arm with pliers and tapped around the cover with a dead blow. It came off with a loud pop.

Actuator with the 3 ball bearings looked fine so I clocked that correctly and reinstalled. Don't recall looking too closely at the clutch itself. Now I have this extra slack before the clutch begins to disengage and even bottomed on the clutch cover it still drags. I have a feeling I broke something inside, hopefully not anything that requires pulling the engine or much worse splitting the cases. Fresh out of clutch cover gaskets so have to order more. Guess I'll have to pull the cover and see what I have because something is definitely not right.

Sucks to be this close and have more issues. Aside from the clutch there are little things I need like headlight trim ring. Mine is dented and scratched and didn't notice so never sourced another. Minor pieces like that I'll have to replace with either better used or new parts... And of course the seat which is a huge eyesore. Battery doesn't seem to want to take a good charge. Have to kick it over, it's possible my misfiring occasionally could be low voltage causing issues with the Dyna. Add a new battery to the list too.

Offline SOHC4 Cafe Racer Fan

  • Speak up, Whipper-Snapper! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 15,731
  • SOHC/4 Member #1235
Re: CB750 K1 project
« Reply #184 on: May 26, 2014, 05:27:54 PM »
Gorgeous!!  ;D  Very well done!
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)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"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
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #185 on: May 27, 2014, 07:57:10 AM »
Pulled the clutch cover before calling it a night. Nothing glaringly obvious. The actuator jobbie with the ball bearings looks like it has a fair amount of wear, as most do I guess. I thought maybe that was broken or the lifter plate had cracked. I'll check over it again before putting it together and doing the clutch adjustment again. Maybe I'm just missing something because nothing looks obviously damaged.

Who do you guys use for agreed value insurance? Anyone ever have to make a claim? Did online quotes for a few and prices were kind of ridiculous for the ones I could even get past the hoops they want you to jump through. Hagerty seems not too ridiculous on price so I sent an application to them. Not holding my breathe as they declined to offer me coverage years ago on my '68 for various reasons. Their reason last time around was that my daily driver was older than the vehicle I wanted to insure with them, absurd. No hassle with the application this time so I'm hoping they've changed a bit and my daily driver these days is about 2 decades newer. Curious on other people's experiences.

Offline cheftuskey121

  • Super Newbie
  • Expert
  • ****
  • Posts: 1,305
Re: CB750 K1 project
« Reply #186 on: May 27, 2014, 09:23:12 AM »
gorgeous man. that's the nicest it's ever going to look so enjoy it ;)

I use declared value with progressive and I had to make a claim last october when I got hit. totalled the bike out and I got a $5k check. bought it back for chump change too. terrible circumstance but good experience with the insurance company for once.

we want video of it running!

Offline rtbmrgl

  • Expert
  • ****
  • Posts: 795
  • Got Points! Roseville, Ca
Re: CB750 K1 project
« Reply #187 on: May 29, 2014, 05:17:33 PM »
Got it together.




Looks nice, bet it sounds good too. 8)

It looks like the bike might leans to far with no block under the side stand. Maybe it my imagination, hope so.
thanks, Mark
Roseville, Ca

Got Points!

1973 CB500 back yard find 1243 orig mi,  http://forums.sohc4.net/index.php?topic=124285.0
1976 CB750 Restoring,        http://forums.sohc4.net/index.php?topic=132997

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #188 on: May 29, 2014, 06:52:17 PM »
Yes it does seem to lean a bit far. :( I think maybe the Ikon shocks are a little longer than what was on there previously, I'll have to measure and see. It also seems easier to get on the center stand so I suspect that's the case. Unfortunately with the Yoshi pipe from Yamiya the center stand doesn't work. Found that out after ordering but looked like it would work after putting the exhaust on, then unfortunately it hits the pipe so I'll have to remove the center stand.

Just as well from one perspective as the center stand on a previous bike almost got me killed a time or two in a fast hard left turn. I remember one time coming back from a show passing my buddy then coming up on a long hard left turn real fast, guard rail and a small lake on the other side and I was going straight at a couple riding a cruiser who had stopped on the shoulder of that turn and were looking out over the lake. Thought I was going in the drink and according to my buddy throwing sparks through the turn as I leaning against the center stand. I don't ride that aggressively anymore though.  ::)

Got the clutch back together and working correctly this time. After adjusting and on a cold engine it released fully with no drag. Putting into first it would want to jump forward a split second but then felt like no load on the transmission as it was the easiest I've ever had a CB750 go into neutral. Thought I was fixed. Went for a test ride and after it was good and up to temp it's dragging a bit and hard to find neutral as is typical for these bikes. Maybe I'll try adjusting to get a little more release and if no love then new frictions and steels. These measured in spec and didn't seem warped so I reused them. I also drilled (8, I think) additional holes in the inner basket for additional lubrication. Whatever, I'll figure it out I suppose but it's no worse than any other CB750 I've had.

I thoroughly enjoyed my quick test ride!  :D The bike has gobs of power coming on smooth and firm. It's been about a year so my memory could be foggy, but what a difference a fresh top end along with some port work makes. I did a couple pulls rolling on up to about 6 grand and was very pleased. Smooth and plenty of power. Figure I should give it a little time before winding it all the way out, check/readjust valves/etc. Just wanted to keep riding but unfortunately I was having a minor oil leak. Turns out I forgot the small oil hose from the tank to the transmission and leaking oil. Came back and got that on and cleaned up my mess. Weather is a little chilly and chance of rain anyhow, and the past year of work flashed before my eyes as some prick nearly creamed me pulling out from being parked on the side of the main drag through town, didn't look just pulled out.

I noticed the front of my seat is rubbing against the tank and starting to scuff it, like most bikes I've had. Anyone do anything to prevent this? Or just let it get scuffed since you never see it unless the seat is up or off? I'm a little OCD about the nice paint.

I love how the gauges came out. The green LED lights look great! It's a bit more of a darker more rich and vibrant green as seen with the eye. Picture makes it look brighter and more white.



As for insurance, Hagerty was a no go. They say unlimited miles. If you drive to work more than 20 times a year it's a no go, and if every Friday of summer was good weather I would ride to work 24 times. I'm with progressive now on an agreed value policy with no fuss no hassle for the same price and same agreed value but lower liability (how much damage can a bike cause, and I've never had an at fault accident).

Offline SOHC4 Cafe Racer Fan

  • Speak up, Whipper-Snapper! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 15,731
  • SOHC/4 Member #1235
Re: CB750 K1 project
« Reply #189 on: May 29, 2014, 07:35:34 PM »
The increased lean from the taller shocks is normal.  It shouldn't be an issue.  Mine was fairly extreme until I road the bike and the shocks settled in. 

The center stand interference with a Yosh pipe is also normal.  A Bummer, I know. 
« Last Edit: May 29, 2014, 07:37:11 PM by CB750 Cafe Racer Fan »
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)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"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
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline edhaeuser

  • Hot Shot
  • ***
  • Posts: 321
Re: CB750 K1 project
« Reply #190 on: May 30, 2014, 10:27:33 PM »
Looks Awesome! Nice Job!  I sure would like to hear those pipes.

Offline Terry in Australia

  • Really Old Timer ...
  • *******
  • Posts: 33,281
  • So, what do ya wanna talk about today?
Re: CB750 K1 project
« Reply #191 on: May 31, 2014, 02:41:55 AM »
Looks great mate, congrats on a job well done. Keep playing with your clutch, I'm very lucky in that the one in my bike has the best action of any CB750 I've owned (and I've owned over 20) and it just "snicks" into first gear with no clunk, and finding neutral when hot is easy.

What's great is that I've never touched it, and it probably hasn't been apart since new.

If your Dyna is playing up, it's probably due to low voltage from your suspect battery, Dyna's do not perform well unless they're getting a healthy 12 volts. Cheers, Terry. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline mwvachon

  • Hot Shot
  • ***
  • Posts: 358
  • The Family Heirloom
Re: CB750 K1 project
« Reply #192 on: May 31, 2014, 04:07:58 AM »
Congrats on the build. Looks like we both have new 'toys' to ride this summer. Agreed on the insurance. Progressive let me set my own value on one of my other bikes - a '65 S90 that I insured for $5K because of what I have into it. They don't require an appraisal on anything under $15K. Insured my latest K1 for $12K. Happy riding!
M.W.Vachon
2014 CB1100 Deluxe
1999 Valkyrie I/S
1971 CB750-K1 (Candy Gold)
1971 CB750-K1 (Candy Red)
Project link: http://forums.sohc4.net/index.php?topic=108498.0]
1965 Honda S90
1976 GL1000
1975 CB400F

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #193 on: May 31, 2014, 02:39:31 PM »
Just a few odds and ends left. It was too nice out so had to start enjoying it. Went our for a good long ride. "I got nowhere to go and all day to get there!"  8)

A few excerpts...

Stopped here for lunch, got a few compliments from folks gassing up while out riding.



After taking a winding two lane blacktop that follows the river for a good stretch I ended up here...





After racking up some more miles I found myself here...



Then I took a stroll and found some shade to cool off.



What a great day! Really needed to let some steam off and this was perfect. Spoke briefly with a few interesting people along the way, lots of compliments on the bike. I can't wait to do something about that eyesore of a seat!

Some issues... Slight vibration around 50 MPH, throttle on and perfectly smooth. Faster or slower and feels smooth. Need to check spokes and verify wheels are still true. Rear wheel locked unexpectedly easy on me a time or two. I figure the shoes (new EBC) could use some time to bed in to match the drum, and the tire probably needs some miles to wear off any residual slippery molding release. Should probably adjust the valves, sounds right light it should but want to be sure it's good.

Floats were leaking the other day but had no such issue today. Rocked the bike around and sprayed carb cleaner into the fuel lines after running the bowls dry. Hopefully that did it, if not I'll regret not going through the carbs. Still need to hook up the gauges and sync them.

Clutch definitely drags when hot. No adjusting it out. Probably try new steels and frictions as I've already cleaned them and have done all the oiling improvements I've seen. Use best pump I could get my hands on and put new seals in it, new oring in countershaft oiler, extra holes in basket.

Checked engine temp after getting back. Looks like pretty consistent 250-255 across the head front and left side. Right side was a bit cooler at 235-245. Pipes were hard to get a read on(read very low, almost ambient), maybe my IR gun doesn't like the round profile and chrome. Oil temp as measured pointing down into tank was ~145* though I did see a high of 165* on the dipstick immediately after removing it. Seems fine to me, a bit cool maybe. ~250* on the head also seems pretty darn hot, but this is the first air cooled engine I ever measured temp on. On a typical car engine 230* is where damage starts to occur, failed head gaskets, etc. Are all these temps fairly normal or should I be concerned? If I should be concerned what should I do about it? I did use HD studs as cheap insurance and torqued to I believe 20 ft/lbs (I think range was 18-22, so I went in middle since I've read about snapped studs here). Bike ran great overall and idle was consistent after warm if slightly rough (clutch chatter, not feeling rough).

For insurance I'm at $10k value. I figure the value is somewhere in the $10k-$13k range from looking at either very good original or restored bikes that sold on eBay. Some of those are K0s, a few are K1, but surprising some are K2-K6. If I had HM300s I'd definitely up the value, though I'm considering it as it. One of these days I'll add up my receipts and not sure how to account for all the time. I'm paranoid about something happening even as small as a scratch or scuff, though today I was able to let go of my worries and just enjoy the ride.  ;D

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #194 on: May 31, 2014, 03:30:47 PM »
Looks great mate, congrats on a job well done. Keep playing with your clutch, I'm very lucky in that the one in my bike has the best action of any CB750 I've owned (and I've owned over 20) and it just "snicks" into first gear with no clunk, and finding neutral when hot is easy.

What's great is that I've never touched it, and it probably hasn't been apart since new.

If your Dyna is playing up, it's probably due to low voltage from your suspect battery, Dyna's do not perform well unless they're getting a healthy 12 volts. Cheers, Terry. ;D

I don't think any adjustment is gonna fix this. Clutch fully releases quite towards the beginning on pulling it, probably but half travel. The other half should be creating more slack/space between the disks yet it still drags. When cold it shifts beautifully. Any change this could be oil relatived before I do the clutch? Runnig Valvoline 10w40 motorcycle oil (it's what was on the shelf at the closest store). I have usually run GN4 previously and before I knew any better for a wet clutch whatever 10w40 or 20w50 was cheapest. Never noticed a big difference in clutch action or how the engine runs between the oils I've rna over the years, not significant enough to recall anyhow.

I did get a new sealed AGM battery, forgot all about my stumble today but it never missed a beat so I'm better the dyna was cutting out accelerating from a stop due to low voltage. Old battery wouldn't charge above 10v or so.

Offline mwvachon

  • Hot Shot
  • ***
  • Posts: 358
  • The Family Heirloom
Re: CB750 K1 project
« Reply #195 on: May 31, 2014, 06:35:53 PM »
On your comment about the rear brake locking up - I've been riding the Family Heirloom off and on for the better part of 20+ years (both pre- and post-restoration) and have always found that it was very easy to lock up the rear brake. I don't know if its the weight distribution, or if the design has more brake capacity than required, but I've had to warn others when they try to ride this bike. The new (Red K1) exhibits the same potential for this. I primarily brake front anyway, but have always been mindful of what that rear pedal can do, especially in the wet!
M.W.Vachon
2014 CB1100 Deluxe
1999 Valkyrie I/S
1971 CB750-K1 (Candy Gold)
1971 CB750-K1 (Candy Red)
Project link: http://forums.sohc4.net/index.php?topic=108498.0]
1965 Honda S90
1976 GL1000
1975 CB400F

Offline Terry in Australia

  • Really Old Timer ...
  • *******
  • Posts: 33,281
  • So, what do ya wanna talk about today?
Re: CB750 K1 project
« Reply #196 on: May 31, 2014, 08:22:42 PM »
Looks great mate, congrats on a job well done. Keep playing with your clutch, I'm very lucky in that the one in my bike has the best action of any CB750 I've owned (and I've owned over 20) and it just "snicks" into first gear with no clunk, and finding neutral when hot is easy.

What's great is that I've never touched it, and it probably hasn't been apart since new.

If your Dyna is playing up, it's probably due to low voltage from your suspect battery, Dyna's do not perform well unless they're getting a healthy 12 volts. Cheers, Terry. ;D

I don't think any adjustment is gonna fix this. Clutch fully releases quite towards the beginning on pulling it, probably but half travel. The other half should be creating more slack/space between the disks yet it still drags. When cold it shifts beautifully. Any change this could be oil relatived before I do the clutch? Runnig Valvoline 10w40 motorcycle oil (it's what was on the shelf at the closest store). I have usually run GN4 previously and before I knew any better for a wet clutch whatever 10w40 or 20w50 was cheapest. Never noticed a big difference in clutch action or how the engine runs between the oils I've rna over the years, not significant enough to recall anyhow.

I did get a new sealed AGM battery, forgot all about my stumble today but it never missed a beat so I'm better the dyna was cutting out accelerating from a stop due to low voltage. Old battery wouldn't charge above 10v or so.

No worries mate, as soon as I read "Valvoline" the hairs on the back of my neck stood up, I only used it once in my Kawasaki Z900 and had the worst ride of my life, the clutch was either "on" or "off" with no in between, couldn't find neutral at the lights, I couldn't ease it out at low RPM's, it'd just stall, so I'd have to wheelie away from the lights just to keep going.

I dumped it out and just put Mobil 20W-30 car oil into it (don't use any oils with "friction modifiers" in it or it might start to slip) and it was fine. Try changing your oil before you pull your clutch. Good to see the new battery solved your ignition problems. Cheers, Terry. ;D 
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Dunk

  • Expert
  • ****
  • Posts: 932
Re: CB750 K1 project
« Reply #197 on: June 03, 2014, 06:28:22 AM »
Put another 90-100 miles on it Sunday. No change in clutch. Good to hear about your experience with Valvoline. I'll give it a few more miles and change the oil to GN4. Hopefully that will fix it. Seems strange that it is the best I've ever had a CB750 clutch when cold but after 10-15 mins it's the worst I've ever rode.

Rear brake is feeling a bit less touchy now after more miles, but yes they've all been pretty easy to lock. Feels more normal now.

Offline cheftuskey121

  • Super Newbie
  • Expert
  • ****
  • Posts: 1,305
Re: CB750 K1 project
« Reply #198 on: June 03, 2014, 05:53:32 PM »
hey cadunkle, is it cool if I nominate your bike for BOTM? we have two other K1's (gold and red, and it would be wicked to have blue too)

Offline Terry in Australia

  • Really Old Timer ...
  • *******
  • Posts: 33,281
  • So, what do ya wanna talk about today?
Re: CB750 K1 project
« Reply #199 on: June 04, 2014, 03:09:26 AM »
I'll second the nomination. The blue K2 I restored in 2010/11 won BOTM in February 2011, and I was chuffed! Cheers, Terry. ;D

 
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)