Author Topic: Ross’s 1975 CB750 K5  (Read 7302 times)

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Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #150 on: March 23, 2024, 12:03:27 PM »
So I’ve pestered the paint shop enough that we’re getting on with painting the tank.  To save a bit of labour cost, I went down to the shop to lay out the masking to paint the black cheeks. 

I referenced the many photos I took of measurements of the original stripes.  I did this before sandblasting the tank.  Should have been a piece of cake.  You know what they say about when you assume. 

I had the area to be painted black all nicely mashed off.  Then we got out the stripe kit I had bought from PartsNmore (same company as Vintagecb750) to check and make sure of the fit.  Not even close. 

The vertical section of the stripe, at the front of the tank is shorter than original.  The upper part that flows back to the seat has a pronounced reverse curve to it.  In short, it not close to original.

We ended up masking from scratch and just winging it.  My painter was really good but I was/am very disappointed.  It will work, and most people I’m sure would not notice the difference, but it won’t be correct.  Pisses Moffatt considering the effort and expense of doing this.

In hind sight, I’d advise anyone who wants to renew the bodywork to consider getting a complete kit from Yamiya.  You can recoup some of the cost by selling your old stuff.  Or hang onto it it like the pack rats we all are.


Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #151 on: March 23, 2024, 12:13:29 PM »
Also regarding the stripe kits.  You can also get them from Diablo Cycle (formerly Reproduction Decals).  They don’t show much Honda stuff on their website anymore because they had a big dustup with Honda a few years ago but they still sell all of the reproduction items.  And they have a phone number where you can talk to an actual person!  You’ll end up talking to Ellen.  I’ve spoken with her a few times over the years.  She’s very nice and very helpful. 

I spoke with her about the stripes as I didn’t get a response from PartsNmore, and I was in a bit of a state.  She said , I’m not so many words, that places like PartNmore and Vintagecb750 (and others) get their stripes from Diablo Cycle and they’ve shipped thousands all over the world.

Oh well.  We’ll make the stopes work.  But what a pain in the but.  It took me most of the day in the paint shop to figure it out.  I’m hoping to have the tank back by the end of the week.

Online HondaMan

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Re: Ross’s 1975 CB750 K5
« Reply #152 on: March 24, 2024, 07:24:11 PM »
Or hang onto it it like the pack rats we all are.

Hey! I'll have you know, I resemble that remark. ;)
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #153 on: March 26, 2024, 08:11:21 AM »
Carb question. 

I’ve always had difficulty setting air/fuel mixtures, whether using an air screw or a fuel screw.

Using the tachometer on the bike or a vacuum gauge, I not really able to discern changes in rpm when adjusting the screws.

Can anyone point me to a good tutorial on this?  Is there a good post on this site anywhere?

Cheers,
Ross

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #154 on: March 26, 2024, 09:42:08 AM »
Tank black cheeks done


Offline BenelliSEI

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Re: Ross’s 1975 CB750 K5
« Reply #155 on: March 26, 2024, 10:01:02 AM »
Carb question. 

I’ve always had difficulty setting air/fuel mixtures, whether using an air screw or a fuel screw.

Using the tachometer on the bike or a vacuum gauge, I not really able to discern changes in rpm when adjusting the screws.

Can anyone point me to a good tutorial on this?  Is there a good post on this site anywhere?

Cheers,
Ross

Ross…. You’re not the only one! I’ve decided I must be an idiot. I never see much difference either. I set them to the recommendation and leave them alone!

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #156 on: March 26, 2024, 10:53:38 AM »
The completed tank is some way off. 

Painter wants to wait a week before sanding the edges off of the black so they don’t show through the stripes.  Then clear and wait a week to off gas completely before applying the stripes.  Add the stripes and wait two weeks for the water underneath the stripes to completely dissipate.  Then the final clear.  So at least 4-5 weeks.  Perhaps a bit cautious on the curing, but he wants it perfect, as do I.  I have another motorcycle to ride in the meantime.

Offline BenelliSEI

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Re: Ross’s 1975 CB750 K5
« Reply #157 on: March 26, 2024, 03:20:37 PM »
“Worth the wait”.

Offline MauiK3

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Re: Ross’s 1975 CB750 K5
« Reply #158 on: March 27, 2024, 07:52:56 AM »
Agreed on setting the mixture screws, I thought I was the only one!
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Offline BenelliSEI

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Re: Ross’s 1975 CB750 K5
« Reply #159 on: March 27, 2024, 08:39:17 AM »
Agreed on setting the mixture screws, I thought I was the only one!

Join the club!

Offline seanbarney41

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Re: Ross’s 1975 CB750 K5
« Reply #160 on: March 27, 2024, 09:46:53 AM »
Agreed on setting the mixture screws, I thought I was the only one!

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me too!
If it works good, it looks good...

Offline BenelliSEI

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Re: Ross’s 1975 CB750 K5
« Reply #161 on: March 27, 2024, 07:05:53 PM »
Agreed on setting the mixture screws, I thought I was the only one!

Join the club!
me too!

This is so funny! I thought I was just “insensitive”!

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #162 on: April 02, 2024, 04:28:06 PM »
So, my paint shop tried installing the stripes today.  They do not fit at all as original, and ended up damaging the left side stripe.  Will try the right side tomorrow.  I’ve ordered another set.  No choice really, but to make them work. 

I did a bit of sleuthing.  It seems that Reproduction Decals, now called Diablo Cycle in London Ontario is the manufacturer of the stripe kits that everyone sells.  I’ve seen them on my neighbour’s K5, so I know they’ll work, but they are not “correct”.  They’re shorter at the front, so the black area is smaller, and the upper portion is much more of an S curve which is very difficult to get laid down and wants to buckle and crease.  Nor does the vertical part at the front have correct angles at the corners.  A real pain in the a**.


I’ve had to order another stripe kit and hope it works out better.  No choice at this point.  I’m in too deep now to abandon it and order a Yamiya body kit, which is what I should have done from the outset.

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Re: Ross’s 1975 CB750 K5
« Reply #163 on: April 02, 2024, 07:41:51 PM »
Carb question. 

I’ve always had difficulty setting air/fuel mixtures, whether using an air screw or a fuel screw.

Using the tachometer on the bike or a vacuum gauge, I not really able to discern changes in rpm when adjusting the screws.

Can anyone point me to a good tutorial on this?  Is there a good post on this site anywhere?

Cheers,
Ross

Ross…. You’re not the only one! I’ve decided I must be an idiot. I never see much difference either. I set them to the recommendation and leave them alone!
+1!
It isn't possible to listen to the engine and adjust the air screws for 'best idle', for example, primarily because the cylinders interact. It's not like a single, nor even a twin. Also, 50+ years later the carbs themselves have often receded where the air screws seat, so they must be opened less than the 1970s spec to get the same mixture. I've long used 'slightly less than 1 turn' for the air screw settings.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #164 on: April 02, 2024, 10:09:17 PM »
Carb question. 

I’ve always had difficulty setting air/fuel mixtures, whether using an air screw or a fuel screw.

Using the tachometer on the bike or a vacuum gauge, I not really able to discern changes in rpm when adjusting the screws.

Can anyone point me to a good tutorial on this?  Is there a good post on this site anywhere?

Cheers,
Ross

Ross…. You’re not the only one! I’ve decided I must be an idiot. I never see much difference either. I set them to the recommendation and leave them alone!
+1!
It isn't possible to listen to the engine and adjust the air screws for 'best idle', for example, primarily because the cylinders interact. It's not like a single, nor even a twin. Also, 50+ years later the carbs themselves have often receded where the air screws seat, so they must be opened less than the 1970s spec to get the same mixture. I've long used 'slightly less than 1 turn' for the air screw settings.

Ok.  That’s good info.  Thanks.  One day when I get the tank back, I’ll actually be able to ride it.  So far I’ve only had it out in the lane scaring the neighbour’s cats and children.

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #165 on: April 22, 2024, 11:09:03 AM »
Thought I’d give this a bump.

Hopefully I’ll get the tank back this week.  All that’s left is to polish off the clear coat ridges on the edges of the stripes. 

I have to say I’m not happy with the quality of the stripe kit.  And I’m pretty sure that all of the retailers get them from the same supplier.  The overall height of the stripe at the front is less than original.  The overall shape of them isn’t correct either.  The material they’re made of doesn’t allow them to be shaped without wrinkles.  The adhesive is such that once it touches the tank you can’t pull it off and re-lay it.  You can see quite readily that it is dot printed as the tighter radiuses are jagged and you can see the dots. 

Had I known this, I would have sprung for the body kit from Yamiya.  Especially given that I had to get new side covers since the originals were not worth trying to salvage for paint.  And because I didn’t know of a comparable paint code, I got the expensive stuff from Montana.

When I pick up the tank, the painter and I will find a matching current paint code and I’ll post it in this thread. 

Here’s a pic before final polishing.

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #166 on: April 26, 2024, 01:07:50 PM »
Ok.  So here she is. 

Thanks again for the sticker, John.

Offline denward17

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Re: Ross’s 1975 CB750 K5
« Reply #167 on: April 26, 2024, 01:14:52 PM »
Beautiful!

Love that blue.

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #168 on: April 26, 2024, 02:11:50 PM »
Ya, I love it.  When I picked up the tank, I forgot to try and get a match of modern paint.  But I’ll try to get it next week and post the match here.

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #169 on: April 26, 2024, 07:04:27 PM »
Took the Honda out for a toodle around the neighbourhood.  Runs well.  LOUD.  Had to readjust the clutch cable down at the bottom.

Starts and idles down nicely.  I reckon it's running lean.  Lots of popping on deceleration.

But man, is she beautiful.

Offline newday777

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Re: Ross’s 1975 CB750 K5
« Reply #170 on: April 27, 2024, 03:09:32 AM »
Yes the blue is fantastic. Very close to my K5 original Planet Blue is.
I have some tanks I'm going to try painting myself. I may talk to my friend that has a sign shop to see if he can replicate the stripes in the full size, hopefully to be better than the ones available like you got. That is disappointing to hear the decals can't be set properly without wrinkles to the correct shape and size. Did you talk to the supplier about the stripe problems?
And BTW you aren't the 1st to have the problem of the stripes not being able to get set properly. I've seen many on the tanks of multiple 750s that were up for sale with the same out of place stripes. It looks good for a rider but will be picked out quickly in judging at a show unfortunately. I'm not nitpicking your bike, just preparing to paint and stripe my tanks in the future.
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #171 on: April 27, 2024, 11:57:04 AM »
Yes I did speak both to the supplier (Parts N More via email) and the producer (Diablo Cycle/Reproduction Decals via phone).  They don’t seem to see the issue.  They’ve been selling them for years, all over the world, yadda, yadda, yadda. 

My paint shop did a really good job though, and it looks great.  I ended up having to purchase a second set of stripes because of the issues mentioned above.  I’m quite happy with the results though.  I’ve no choice.  I’d much rather it were perfect, but that’s life.  First world problems, eh?

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #172 on: May 11, 2024, 07:42:25 PM »
So, yesterday I took the CB750 out for its first real shakedown ride.  Roy and I rode out to Agassiz.  There was a fellow out there who was selling a Dyna electronic ignition for $35.  I reckoned if it’s in working order, that’s a pretty good deal.  In any case it was a good reason to get my ass out for a ride.

We headed out on the freeway.  I wanted to run it at speed and temperature to burn off the moisture that has been in the crankcase since I started it.  The bike ran well, as I expected.  An issue that’s become very apparent is the amount of effort it takes to turn the throttle.  It was an inordinate amount.  I’d only run it about 100 miles around town at this point.  I put it down to an overly strong carb return spring.  But as our ride progressed, the wrist twisting effort became greater, and the throttle seemed to catch and bind upon input.  Hmmm.

So this evening I pulled the tank and disconnected the throttle cables.  The return spring seemed absolutely fine when actuated be hand.  Hmmm.  The pull cable seemed a bit catchy though.  I opened up the right hand switch block to access the throttle grip tube.  Disconnected and inspected the cables there.  Really odd.  On the pull cable, the inner sheath had been pulled up and was wrapping along with the cable around the throttle tube.  Apparently, somehow the sheath has been pulled from inside the cable housing.  I pushed the inner sheath back down out of the way and applied some 3in1 oil.  Reconnected the cables to the carbs.  Feels great.  Now, if the issue reoccurs, I’ll have to replace the cable.  Cheap Chinese cables.

Another small issue I noticed was a catch when I applied the rear foot brake.  I found that I had the upper bolt of the brake torque arm installed the wrong way.  The threaded end was catching on the actuator rod.  I removed the bolt, flipped it around so the threaded end was the other way.  Clearance achieved. Duh!

The ride yesterday was about 140miles.  Towards the end, found that the clutch was juddering upon engagement.  I haven’t ridden today so I don’t know if it’s settled after cooling.  In any case, something is not quite right.  Any thoughts from anyone?  Friction discs?  Springs?  Is there a recommended upgrade?

Offline BenelliSEI

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Re: Ross’s 1975 CB750 K5
« Reply #173 on: May 12, 2024, 08:33:28 AM »
Wow….. Hadn’t looked for a while. Bike/paint looks fantastic.

Let the clutch cool down and try again. If the bike sat a long time and the plates were “dry” it might just need a few rides. You could pull them apart, clean and soakin fresh oil, but I’dride it a few times before tearing into it.

Offline Galactica

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Re: Ross’s 1975 CB750 K5
« Reply #174 on: May 12, 2024, 02:25:31 PM »
I took it out this morning.  Clutch seems fine now.