Long Sleeping '79 CBX Restoration

Hey, what projects are you planning or preparing for? CBX, other motos, workshop, WHATEVAH!
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shiskowd
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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

Syscrush wrote:
Tue Jan 26, 2021 1:42 pm
It looks like you're doing a lovely job with this restoration project - and the documentation and careful photo taking are great. It always puts a smile on my face to see good shop photos in a thread like this.

Thanks again for sharing this, and good luck with it!
Thank you :-) , my other passion that I don't spend nearly enough time is photography so it's fun to mix them up.

I wanted to ensure I got the primary shaft lined up correctly even though I've had the cases together for some time :pray: . Loose fitted the clutch cover and the timing bits - everything lines up :D .

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I got the carbs together finally. Thus ends an easy 40 hours I stunk into these and probably half that again researching best practices in addition to Mr. Nixon's book. The last struggle was setting the accelerator pump. Mike Nixon commented on one of the forum threads he likes to see 6mm of pump shaft travel. I couldn't get anymore than the spec'd 3mm in the manual regardless of the adjusting arm position. I'll need to leak check them in the garage when it warms up some. Fingers crossed on their operation - really want to break the newb rule of thumb that I'll have them on and off 3 times before I get it right...

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Next up was the clutch rubbers. I could detect slight movement when applying some torque by hand so I ordered Bert's kit. Installs easy enough and it's super tight now. Great pictorial on Restocycle's Facebook site that walks you through this - thanks Nils!

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Continuing with projects I can do in my basement while this cold spell passes in Alberta... on to the gauges.

I purchased new faceplates and needles from Bert at SIxCenter, wanting the metric primary faces but not realizing they didn't have the sub miles units as the Canadian bikes have. Does anyone have a source for the dual units with KM/hr being the primary scale??

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The exercise is a bit nerve wracking, not wanting to bugger up the delicate pieces that haven't been apart for 40+ years. Placing the needle back on the instrument is a trial and error exercise to scale it properly. I used an electric drill with the RPM confirmed by a contactless laser tach. The camshaft spins at 1/2 the speed of the crank, the tach gear spins 1/2 the speed as the cam, so you need to multiply the drill speed by 4 to get the indicated RPM. You can see in the photo that 1,970 RPM x 4 = 7,880 RPM which is about where the tach needle was pointing. However that mechanism works in the tack, it is very linear at lesser tested speeds so I was pleased and placed the glass back on after a thorough cleaning. I confirmed the speedo similarly but there's more math involved with the front tire diameter and the gear reduction in the speedo cable drive.

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They don't build speedometers like this anymore, I guess no manufacture makes mechanical speedo anywhere these days...

Question - what is the accepted practice when you install a gauge cluster from another bike on to a chassis that you acquired that had no speedometer (therefore no odometer) and you have no idea of the previous mileage? The title on the bike receiving the speedo had no indication of mileage and the previous owner had no idea as the speedo disappeared prior to his purchase. I figure I could wind the odometer to some value now but what value understanding that I'll need to fully disclose the bikes history and this rather thorough restoration should I elect to sell the bike at some point?

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2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
Long Sleeping '79 CBX Restoration > viewtopic.php?f=102&t=11699

daves79x
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Re: Long Sleeping '79 CBX Restoration

Post by daves79x »

Did you stretch the accelerator pump rod spring to about half again it's normal length? This way you WILL get as much travel as the limiting fork setting will allow. But don't expect it to stay this way for very long in service. Dirt, hardening of the diaphragm, other issues will gradually limit pump travel, to where, some years down the road, it will be effectively useless. You can remove very few carbs from CBXs that the accelerator pump isn't frozen. It's just a bad design.

Dave

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Re: Long Sleeping '79 CBX Restoration

Post by daves79x »

About the primary shaft timing - yes, it is a bit fiddly. What I do is, before the halves are sealed together, is to take the clutch cover and advancer shaft and temporarily install it on just the case half with the primary shaft (top half). Then slip the pulser unit on and you can easily see in a second if your timing is correct. If not, it is easier to correct than to find out it's wrong after the cases are together.

Dave

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Re: Long Sleeping '79 CBX Restoration

Post by EMS »

The speedometer with km/h main and mph secondary scale was a Canadian market version only. With Bert being in Europe, he only has the Euro, km/h scale only, version. Maybe Tim's, who also supplied replacement faces and refinished instruments has the dual scale.

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Re: Long Sleeping '79 CBX Restoration

Post by daves79x »

I think Bob at CBX Performance can likely fix you up.

Dave

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Re: Long Sleeping '79 CBX Restoration

Post by Jeff Bennetts »

Your Speedo mileage question?

IMHO, as long as you document everything you stated in your previous post above, include some pictures of your build, it would be fine to set it to Zeros, at least it will reference something factual, miles since the/your restoration.

Just throwing it out there! I’m curious what the other guys here feel about it, it’s an important question!
Maybe it’s something that’s dictated by law, some kind of procedure, titled, State by State/Province?

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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

daves79x wrote:
Fri Jan 29, 2021 7:02 am
Did you stretch the accelerator pump rod spring to about half again it's normal length? ...

It's just a bad design.

Dave
I found an earlier post of yours with this suggestion, I stretched it as far as I dare. There is so many friction points that interfere and are susceptible to grim and such as you mention. That accelerator system was truly an afterthought in an otherwise well thought-out setup. Do other Keihin carbs on this older Hondas have similar?
Last edited by shiskowd on Fri Jan 29, 2021 7:04 pm, edited 1 time in total.
2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
Long Sleeping '79 CBX Restoration > viewtopic.php?f=102&t=11699

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shiskowd
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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

daves79x wrote:
Fri Jan 29, 2021 7:06 am
About the primary shaft timing - yes, it is a bit fiddly. What I do is, before the halves are sealed together, is to take the clutch cover and advancer shaft and temporarily install it on just the case half with the primary shaft (top half). Then slip the pulser unit on and you can easily see in a second if your timing is correct. If not, it is easier to correct than to find out it's wrong after the cases are together.

Dave
I saw a thread with your suggested 'pre-assembly check' after I had already mated the cases together which prompted me to install the timing parts to check. During assembly I used a couple of straight edges and carpenters square to find the right spline position on the primary chain driven gear. I got it right but could have easily been off requiring a do over.
2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
Long Sleeping '79 CBX Restoration > viewtopic.php?f=102&t=11699

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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

Haven't posted for a while so some catching up.

I wanted to zero the odometer for this restoration, again, not knowing the actual mileage or if the gauge set was from the bike/engine that I'm working with. Purchased a surplus DC motor and rigged up a drive system with a piece of a tach cable to keep the alignment. 10 days later (at ~200 km/hr) the odometer rolled over to zero. I lighly lubed the speedo gearing a few times but seemed to manage the continuous spinning very well.

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While the speedo was spinning I worked on repairing/reinforcing the headlight shell. The shell had a piece missing o both sides where the shell fastens and the tab at 11 o'clock was broken through that holds the headlight mount ring.

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Strengthened the 11 o'clock tab in the direction of the force the lamp frame ring will apply with some stainless safety wire that is epoxied to the shell.

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Lots of fiddling with fiberglass reinforcing and resin to fill in the pieces that were missing. I understand this is a right of passage to restore these now unobtainium shells. Please with the result.

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2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

I purchased an Ingitech digital ignition some months back and being a nerd for such things, I have been eager to test on the bench prior installing on the bike. I rigged up the test using a pulse generator installed in a clutch cover with the advancer installed such that I can spin it by hand.

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I picked up a set of coils and hi tension leads from a 2001 Goldwing that CBX-tras had suggested. Used those coils/caps and a set of resistor plugs that I had ground together in an aluminum plate.

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Powered it all up and work flawlessly right out of the box. The connectors from Ingitech are wired up to be plug and play.

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Below is a screen capture of the advance map that is used with the mechanical advance is fixed solid. The unit manages the 10 degree ignition advance that the pulse generator is positioned (essentially the 'F' mark on the crankshaft) and adds the additional advance as the engine RPM increases. Ingitech has also has a map when using the stock mechanical advance mechanism (the programmed advance is flat leaving the actual advance to the flyweights and springs to manage). The total advance Ingitech suggests is 35 degrees verses the stock mechanical 31 degrees. Looking forward to see how well it works.

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2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

I finally got the balance of the head together. Everything was going well until I dropped one of the 6mm washers from genesounds upgraded cam cap holder bolt kit down the cam tunnel :shock: :o :? ...

I spent an hour with a magnet, mirror, inspection light trying to find the washer. I took off the oil pan, shook the engine, blew compressed air through it. Resorted to spinning it upside down on the engine stand, more shaking, compressed air - nothing. I swept the floor multiply times in case it had actually fallen out and I missed it. Nothing... What a rookie mistake :doh: There was enough oil and assembly lube that had likely stuck the relatively light washer somewhere I can't see it and won't release.

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Not wanting to roll the dice in hopes that the washer would fall safely to the bottom of the engine when it actually started, I proceeded to take the whole mess apart, right down to splitting the cases. I immediately found the washer resting quietly, stuck against the side of the bottom half of the engine case under cylinder #1. When I spun the case it would have dropped from the center of the engine through the openings in the end of the case. Lots of relief that I found it so quickly verses taking apart the primary drive/transmission.

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A happy ending, all in all. I got to experience the joys of cleaning again the mating surfaces of the cases and assembling an amazing engine. At least that's what I keep telling myself... :lol:
2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
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Re: Long Sleeping '79 CBX Restoration

Post by NobleHops »

I like the cut of your jib, sailor. Great mojo!
Nils Menten
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Re: Long Sleeping '79 CBX Restoration

Post by EMS »

Hindsight is always 20-20... I keep a supply of clean rugs and paper shop towels handy to stuff into nearby holes when I work on engine and R&R small parts. I had my share of items disappearing into holes. Not again!

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Re: Long Sleeping '79 CBX Restoration

Post by Syscrush »

Great work! Really looking forward to hearing how that ignition setup works for you.

I don't know if it would have helped or not in this case, but I was surprised to learn recently that you can get a decent 8mm borescope / endoscope from Amazon for about 35 bucks. Mine has a remote-adjustable light and came with a hook attachment for finding and fishing out stuff like this.

I wasn't able to get it working via WiFi from my phone (a common complaint), but had no problems with it wired via USB to my Windows laptop.

https://www.amazon.ca/gp/product/B07B92 ... UTF8&psc=1
Phil in Toronto
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Pics of Perry, my '79.

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shiskowd
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Re: Long Sleeping '79 CBX Restoration

Post by shiskowd »

Thanks Phil - I thought a borescope would be much more expensive, leave it to Amazon! I can see many uses for that around the garage home.
2022 KTM 890R, 1982 Pro-Link, 1979 CBX 'Z, 1975 Moto Guzzi 850T
Long Sleeping '79 CBX Restoration > viewtopic.php?f=102&t=11699

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