'Diamond in the rough'

Hey, what projects are you planning or preparing for? CBX, other motos, workshop, WHATEVAH!
daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: 'Diamond in the rough'

Post by daves79x »

Mike - I know you've made reference somewhere in this mile-long thread, but could you remind us again just how many miles you've put on this bike? I was shocked.

Dave

User avatar
bikeymikey748
ICOA Member
ICOA Member
Posts: 496
Joined: Tue Aug 30, 2011 2:52 pm
Location: Montreal, Canada
Location: Montreal, Canada

Re: 'Diamond in the rough'

Post by bikeymikey748 »

Mike - I know you've made reference somewhere in this mile-long thread, but could you remind us again just how many miles you've put on this bike? I was shocked.
Dave, I FINALLY broke the 60,000km. (37,000mi.) barrier last year. Keep in mind this is the second instrument cluster on the bike. The first ‘budget’ item lasted something like 1,500km. before it got trash-canned. Not as high as it should be though seeing as that damned work-place accident cancelled a BUNCH of riding opportunities. As well, Covid kept me out of my high-mileage loops south of the border last year. Here’s wishing us ALL a terrific season in ‘21 !
Looking at the hour-meter I added at the beginning of last year you can see I managed a paltry 96hrs. of saddle time. Neat little addition though...more useless information.

Image

Managed a few more mods over this winter one of which should make front tire changes less of an ordeal. Was never a fan of hanging my calipers and watching them dangle precariously as I messed around with wheel removal/install.
Enter my dry-break brake line fitting. It allows for disconnect of the calipers from the line without having to worry about bleeding the system afterward. Simply disconnect the calipers and set them aside. When done, reconnect them and off you go.

Image
Image

steve murdoch icoa #5322
ICOA Member
ICOA Member
Posts: 4068
Joined: Tue Mar 04, 2003 9:12 am
Location: St. Catharines, On. Canada
Location: St. Catharines, On. Canada

Re: 'Diamond in the rough'

Post by steve murdoch icoa #5322 »

"that's all i can stands, i can't stands it no more!"....i'm moving to Montreal.

Very trick, Mikey.

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: 'Diamond in the rough'

Post by daves79x »

Excellent Mike! This should be an inspiration for those of us that don't get out much on our CBXs these days.

Dave

User avatar
bikeymikey748
ICOA Member
ICOA Member
Posts: 496
Joined: Tue Aug 30, 2011 2:52 pm
Location: Montreal, Canada
Location: Montreal, Canada

Re: 'Diamond in the rough'

Post by bikeymikey748 »

The ‘first’ 70,000+ km.

Image

Winter 2021/22 and no home renos or friends’ bikes to rebuild(ish). Just over 105,000km. on the clock of the CBX, a motor that sees redline on a fairly frequent basis I might add. I was certain that the original cam chains needed replacement and was curious about the condition of the original crank & con rod bearings as well. Seems a no-brainer…hold my beer, I’m goin’ in 😎
You might recollect this motor got a rebuild a little more than 70,000km. ago.
I thought I might share some of the more noteworthy observations that presented themselves along the way.
Here we go…
These boots were brand new and from a reputable supplier. I had been noticing mild ‘sweating’ where they mounted to the head, and that even with stepless screw clamps. They had dried out to the point of being unsalvageable after being removed.

Image

When removing the alternator, I discovered that the small aluminum plug installed in the end of the primary shaft had become adrift at some point. It was loose in the small cavity between the alt. clutch plates and just fell out when the alt. came off! Among other things, it directs a fine stream of oil at the alt. clutch plates. The results were sadly predictable. Curiously, my voltmeter never indicated any charging issues even last fall when I was using my heated grips & vest.

Image

Image

Image

Gave the cams a quick polish, super shape! Nothing untoward going on with their journals either. The Oldham couplings will see replacement with a pair of oversized items from Bert @ Six Center.

Image

Image


Cam & primary chain guides showing multiple cracks of considerable depth and dried condition.

Image

This tensioner (cam chain ‘B’) was a brand new OEM bit 70k ago. Think our motors develop much heat!? I replaced the rubber cover that damps movement caused by the spring’s natural resonance. Fun fact: I noticed the rod that interfaces with the tensioner locking bolt is machined as a wedge with the thicker part facing the tensioner. The locking bolt only has to be snug against it, NOT over-torqued, to arrest it’s movement. Good to know, no 😎

Image

I often read of folks asking after the quality of Cruzinimage piston kits. Here’s one of my big-bore slugs, check out its condition. One picture…

Image


The bearing surface of the starter one-way clutch showing multiple scoring. These surfaces have to be pristine to ensure proper engagement of the three locking rollers. Spent a fair amount of time polishing the imperfections out.

Image

Let’s talk trannies…quick vid illustrating advanced wear on the splines of the countershaft where the sprocket mounts. Check out the difference with the second, replacement, shaft in the video 😎

https://m.youtube.com/shorts/7345QC8_Z9M

BIG surprise with the condition of the teeth on the fifth gear cog on the mainshaft! Curiously, the teeth of its mate on the countershaft were fine.

Image


Folks seem to replace the cloth-covered oil cooler hoses on a regular basis but I don’t recollect any mention of the similar, if smaller, feed line from the upper crankcase to the head, behind the cylinders. It always gave me pause. Fabbed a braided line and put the issue to rest 😉

Image

Image

I also figured that as long as the lump was in pieces I would hit up the plot with a ‘refresher’ coat of colour. Pleased with the result.

Image

Image


In the end, all of the crank & rod bearings required replacement. All journals got polished and OEM bearings were installed. Fun fact: I shopped around and saved BIG by ordering through https://www.cmsnl.com/ . Great folks to deal with, FAST shipping!
As expected both cam chains were roached, and the primary in the bargain as well.
Pistons got new rings (thanks again Mitsuo @ https://www.cruzinimage.net/ ).
New clutch friction plates installed, metal plates looked minty. Valves & seats were lapped to freshen them up.
MAJOR shout out to my good friend Ron Marshall! He stepped up and offered me a deal I couldn’t refuse. From the bowels of an ‘82 lump with 25,000km. he supplied replacement primary, counter & main transmission shafts as well as both cam chain & primary chain guides, primary chain tensioner, and alternator clutch plates (one of which was BRAND NEW from his private stash). I had the parts I needed within days of my asking him. SUPER guy.
As always my ‘support’ dog, Oliver, just had to be in the thick of the action 😋

Image

AshishNJ
Power Poster
Power Poster
Posts: 375
Joined: Mon Mar 25, 2019 10:26 am
Location: NJ USA
Location: NJ USA

Re: 'Diamond in the rough'

Post by AshishNJ »

What a beautiful color of engine paint. What exactly is it ?
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: 'Diamond in the rough'

Post by daves79x »

Not to beat a dead horse, but this folks, is the result of severe overheating. Mike has alluded to as much. I've worked on 100K mile bikes that did not have nearly this much rubber damage. And I've seen pretty low-mile bikes that had very crispy rubber parts. All the result of stop-and-go-driving in urban areas where the engines have been subjected to extreme overheating. Might have been the death of the piston rings too.

Guys, you just CANNOT run these bikes in traffic in the city. You see the direct result. Sorry - back to the show!

Dave

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1714
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: 'Diamond in the rough'

Post by Syscrush »

Me: here's 10 pages over the course of a year as I hem and haw about how to solve every real and imagined issue with my motor.

Mike: Here's a rebuild at 70k km in one post

Me: :o :o :o

Amazing work, as always!

I'm curious, did you take it apart at 70k just because it felt like time, or were there symptoms of trouble?
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1714
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: 'Diamond in the rough'

Post by Syscrush »

daves79x wrote:
Thu Mar 31, 2022 7:11 am
Guys, you just CANNOT run these bikes in traffic in the city. You see the direct result. Sorry - back to the show!
This is a good reminder, Dave.

In your view, is oil temp the whole story, or are cylinder head temps a big issue, too?
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

User avatar
bikeymikey748
ICOA Member
ICOA Member
Posts: 496
Joined: Tue Aug 30, 2011 2:52 pm
Location: Montreal, Canada
Location: Montreal, Canada

Re: 'Diamond in the rough'

Post by bikeymikey748 »

AshishNJ wrote:
Wed Mar 30, 2022 8:09 pm
What a beautiful color of engine paint. What exactly is it ?
Glad you like it 😉 This be the product I shot.

Image


Image
daves79x wrote:
Thu Mar 31, 2022 7:11 am
Not to beat a dead horse, but this folks, is the result of severe overheating. Mike has alluded to as much. I've worked on 100K mile bikes that did not have nearly this much rubber damage. And I've seen pretty low-mile bikes that had very crispy rubber parts. All the result of stop-and-go-driving in urban areas where the engines have been subjected to extreme overheating. Might have been the death of the piston rings too.

Guys, you just CANNOT run these bikes in traffic in the city. You see the direct result. Sorry - back to the show!

Dave
Preaching to the choir, Dave 😉 Though I can count on one hand the times I’ve been jammed-up in traffic. As well, when cruising at a buck thirty (80mph.) my oil temp climbs alarmingly, and that with a larger oil cooler. If I throttle back to 100-120km. the temps return to an acceptable range.
p.s. if recent plug-chops are any indication, my jetting is fine at those engine speeds.
Syscrush wrote:
Thu Mar 31, 2022 8:43 am
Me: here's 10 pages over the course of a year as I hem and haw about how to solve every real and imagined issue with my motor.

Mike: Here's a rebuild at 70k km in one post

Me: :o :o :o

Amazing work, as always!

I'm curious, did you take it apart at 70k just because it felt like time, or were there symptoms of trouble?
Phil, your first remark creased me up 😂 Thanks…I needed that.
As to your question…I was pretty certain my ‘B’ cam chain was past its ‘best by’ date. I got to wondering about my crank & rod bearings as well. Facing another long Canadian winter with not much else to do and being left unsupervised while Sheila was at work…
Turns out it was for the best based on what I uncovered.

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4736
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: 'Diamond in the rough'

Post by daves79x »

Speaking of jetting, what did you end up with? I think those are VB64 carbs with pods?

Dave

User avatar
bikeymikey748
ICOA Member
ICOA Member
Posts: 496
Joined: Tue Aug 30, 2011 2:52 pm
Location: Montreal, Canada
Location: Montreal, Canada

Re: 'Diamond in the rough'

Post by bikeymikey748 »

daves79x wrote:
Thu Mar 31, 2022 6:35 pm
Speaking of jetting, what did you end up with? I think those are VB64 carbs with pods?

Dave
Yup, that’s what I’ve got, Dave.

Image

I installed a stage 3 Dynojet kit.

Image

Using their 124 main jet, the stock 35 Keihin idle jet, needle clip (Dynojet needle) in the second groove from the top, and idle mixture screw out 2-1/2 (!) turns. I have zero fueling issues from idle to past redline. I figure my Yoshimura resonator replacing the supplied D&G item is responsible in no small way for that.

Image

Image

I had experimented with shorter (trimmed) springs for the slides. No bueno 🥺 Thankfully, our very own Steve Murdoch graciously sent me OEM replacements. Thanks again, Steve-Oh.
To be honest, the carbs are apart for a cleaning so checking my set-up was easy this time ‘round. My build notes regarding jetting were a mess from so many trial/error addendums. Though, my idle mixture screw settings caught me up! 2-1/2 turns 😲 Thinking about it, what do you thinking about backing them down and going to a 38 or 40 idle jet. I might mention my fuel mileage is at its worst when I roll at 80km.(50mph.) for extended periods.

User avatar
bikeymikey748
ICOA Member
ICOA Member
Posts: 496
Joined: Tue Aug 30, 2011 2:52 pm
Location: Montreal, Canada
Location: Montreal, Canada

Re: 'Diamond in the rough'

Post by bikeymikey748 »

First off, my apologies for posting more to this thread when there’s more than a fair chance some of what’s here might find a home under another title. My reason is that I just want to add to the continuing evolution of my ‘X’.

On that note…just over 1000km. on the rebuilt motor. I gotta say, replacing the three chains and associated guides made a NOTICEABLE difference. The motor has a wicked whine at idle now. Reminds me of how VFRs with gear-driven cams sound.

The exhaust head pipes directly behind the front wheel were getting sand-blasted from what the wheel was tossing at them.
No bueno.
Took the opportunity to spend a little time with 320 & 400 wet/dry sandpaper and soapy water to attempt a more uniform finish to the entire system. I was shooting for a brushed stainless steel look. Blended it all with Scotchbrite green afterward.
Also jumped on trash-canning the heat wrap that hid the sections of the system I never got chromed after McGyvering ‘em. Made, I think, a proper heat shield out of alloy sheet. Annealed the sheet, cut it to required shape, formed three sections, and ‘soldered’ them together with aluminum rods (minty stuff those). Couple of nuts spot-welded where needed, sandblasted/painted the associated sections and…voila 😋
Fun fact: When the motor was apart the undersides of the pistons for both cylinders 3 & 4 had a golden discolouration of varnish as a result of their compromised air flow/cooling issues ‘cooking’ deposits in that area, the only pistons of the six to be so afflicted. Between that observation, and my #3 head pipe being ‘blued’ I gave the idle mixture screws an extra 1/4 turn out on #3&4. Bingo! No more discolouration on the pipes, driveability seems improved as well.

Image

Image

User avatar
Syscrush
ICOA Member
ICOA Member
Posts: 1714
Joined: Fri Sep 14, 2012 2:29 pm
Location: Toronto, ON
Location: Toronto, ON

Re: 'Diamond in the rough'

Post by Syscrush »

Your bike, your thread, your choice about how to share your progress with the rest of us!

Looks great!

Your story about 3&4 has me really wanting to figure out a way to do a 6x WBO2 setup for my EFI conversion, but I just don't see any way at all to package it that would work. :(
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike...
Pics of Perry, my '79.

User avatar
NobleHops
ICOA Member
ICOA Member
Posts: 3867
Joined: Mon Jan 25, 2010 7:17 am
Location: Tucson, Arizona, USA
Location: Tucson, Arizona, USA

Re: 'Diamond in the rough'

Post by NobleHops »

Fantastic refresh to the jewel that is your bike, MIke. Thanks for taking us along, I learned stuff, as always.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

Post Reply

Return to “Project Threads”