Topic: cb750 woodgrain cafe racer #2 complete 2/21/17

[FGKouki]

Hello,

I'm relatively new here but have had my hands in a few sohc4 projects over the last few years.  Recently I finished my wood grain 750k5 cafe racer bike that I shared a few photos of in my introduction thread on this site.  I have used the resources here for years and decided for the next bike I would post a build diary here.  I hope to complete this bike to a high level like I think I did with the other. 

This is the "woody" bike I did so you don't have to go looking to find my other posts.  It gets people asking a lot of questions anywhere I take it.








So I have started this project with a k8 with 14,000 some miles.  The previous owner started to go through the rear end of the bike and the braking system etc. but was in a rush to sell it and kind of threw everything back on, much of the hardware was still loose.  I took a gamble because it was complete, and a good deal, even though it did not run at the time.  I ended up using the motor [after a tope end rebuild] and swing arm on my woody bike and will be using whatever spares I have around to put this back together.  I have many new goodies to go on too that will help make it something to be proud of.   




found a decent early tank to replace the 78 tank with thanks to a member here.  The later tank doesn't do much for me and the one that came with the bike has an enormous dent on the top left and fuel door. 


bike stripped down and mocking up the single bump type seat pan on the modified frame









I have re-done the factory gauge faces and needles


New brake master with built in light switch


More to follow...

[riverfever]

Ohhhhh. That is.





Really nice. Chris likey. Do you still have this bike. Love the seat and how it flows with the tank.

[SOHC4 Cafe Racer Fan]

The Woody looks like you used an interesting paint process. 

Outstanding job restoring your K8 gauges.  Looking forward to seeing what develops for this build.

[FGKouki]

Next I stripped the frame and swing arm and painted them obsidian black pearl (subaru color).  I left the stem and triple clamp on as it's much easier to hang. 


epoxy primer


base/clear


close up so you can see the rainbow effect in the pearl


Next I get into the motor.

[FGKouki]

Ohhhhh. That is. Really nice. Chris likey. Do you still have this bike. Love the seat and how it flows with the tank.

Thank you Chris.  Yes I still have the bike, it was only completed about a month ago and I still don't have a tag for it!  Sucks for me missing out on this riding weather. 

The Woody looks like you used an interesting paint process. 

Outstanding job restoring your K8 gauges.  Looking forward to seeing what develops for this build.

Thank you.  I did the hydro-dip and painting process myself.  Everything on that bike really besides the aluminum welding and powder coat was all me.  Oh, I left out a photo of the gauges, in the process I lost one of the needles.  You know how those damn things fly across the room when you pry them off.  After looking for about 3 hours I ended up having to design and 3-d print one and did my best to sand it until it was perfectly balanced.  Then the other week I found the original one!  How frustrating. 

[SOHC4 Cafe Racer Fan]

Next I stripped the frame and swing arm and painted them obsidian black pearl (subaru color).  I left the stem and triple clamp on as it's much easier to hang. 


epoxy primer


base/clear


close up so you can see the rainbow effect in the pearl


Next I get into the motor.

Very nice pearl.

What's the story with your motor?  Any go-fast parts in those "new goodies"? 

[riverfever]

The paint on the frame is dynamite.

[Restoration Fan]

Very sexy.  I love the woody bike.  Looking forward to seeing what you do with this one.

Ron

[riverfever]

Is the tank and seat actually painted or is it wrapped?

[Stev-o]

Love the Woody.  Nominating it for BOTM since you state it was just done a month or so ago.

Very impressive build skills.......

[AintNoEasyWay]

Can't miss out on this one. No idea where it's going but have a feeling I'll dig it.

[Bootsey]

After seeing Woody over on DTT, look forward to following this one.

[riverfever]

Is the tank and seat actually painted or is it wrapped?

Wondered if it was dipped too. Found your build on DTT. Now I know. Nice work.

[FGKouki]

Very nice pearl.

What's the story with your motor?  Any go-fast parts in those "new goodies"?

Thanks.  I'm undecided about motor modifications.  The other bike's motor is 100% stock aside from the cycle-x ignition and the exhaust.  With this motor I've run into quite an issue after opening it up yesterday and I'll make a picture post below with more details.  I do have a new points plate, gasket kit, 4-1 header pipe, and either PD or 657b carbs to go along with it.  Will order rings and a few other bits after I take off the head and bores. 

Is the tank and seat actually painted or is it wrapped?

It's painted.  Basically your regular 2 stage paint but with the hydrodip after basecoat but before clear.  The stripes and HONDA are painted on as well.

Love the Woody.  Nominating it for BOTM since you state it was just done a month or so ago.

Very impressive build skills.......

Thank you although I didn't post a build here so I don't know if it's really okay to do.  Thanks again for that tank 

[FGKouki]

Here's what I ran into with the motor yesterday and this post pretty much puts us up to date. 

Bad news already.

Immediately after removing the rocker arms I knew something wasn't right.  The cam is seriously F###'d along with the caps and towers on cyl 1 and 2.  The cam cap on cyl 1. was also very loose, and as you can see, very worn along with the cam tower.  Hopefully this is not a foreshadowing of bad stuff I may find when removing the head and bores. 



camshaft end play:
http://vid7.photobucket.com/albums/y288/greenkouki/cb750/20150611_163658_108705694376128_zpsosjuo3d2.mp4









I will need to wait to have another hand with pulling the head off.  One reassuring thing at this point is I know the compression was good.  This motor did run but had basically no power as the cam lobes would probably tell you.  Where to go from here... Is it worth just getting known good towers and caps and a cam second hand or should I go for a hot cam too?  I don't plan to do any serious head work if I don't have to, but we will see once I have it off. 

[Restoration Fan]

Contact Bill Benton (BillBentONRacing on this forum).  He has other camshafts and cam towers that he'll sell if you need them.

Great guy with an amazing collection of SOHC parts and he gives very fair prices to people on this forum.

Ron

[Stev-o]

If you don't plan on building a hot motor, just rebuild it with good, used parts.  I did that recently with my K7, the camshaft was literally broken in two! I bought a cam from a forum member for $65.

[FGKouki]

Contact Bill Benton (BillBentONRacing on this forum).  He has other camshafts and cam towers that he'll sell if you need them.

Great guy with an amazing collection of SOHC parts and he gives very fair prices to people on this forum.

Ron

Thanks for the suggestion Ron, I've fired a PM off to him to see if he has the parts.

If you don't plan on building a hot motor, just rebuild it with good, used parts.  I did that recently with my K7, the camshaft was literally broken in two! I bought a cam from a forum member for $65.

Good to know Stev-o and thanks for seconding that notion.   

[GizmoDuck]

found a decent early tank to replace the 78 tank with thanks to a member here.  The later tank doesn't do much for me and the one that came with the bike has an enormous dent on the top left and fuel door. 

what kind of tank is that I really like it.

[FGKouki]

It's a 750k3-6 tank I believe.   The seat pan is a fiberglass ducati 750ss style

[SOHC4 Cafe Racer Fan]

Nice combo.

[FGKouki]

Got the head and jugs off.  Thankfully once I removed everything the pistons looked to be in good shape and the bores didn't show much wear either.  However;  I did notice piston #3 was pretty wet so I changed all 8 valve seals while I was in there.  The exhaust valve seal on #3 was especially loose- if I squeezed the old one at the base where it goes over the guide it opened up around the valve stem a few millimeters.

 I honed the bores a tad just to be safe as well.  Cylinder 2  may need one ore pass as there is some very shallow scoring left that I didn't see until I took a flash light to it after the fact.  At this point I'm just waiting on the new rings and then I can clean, assemble, paint, polish, powdercoat etc.

[AintNoEasyWay]

Sounds good. Hope everything keeps going smoothly!

[FGKouki]

I forgot to mention before that one of the 6mm bolts had snapped off in the jugs.  When I tore down the motor the top of the bolt was no where in sight.  I'm beginning to think somebody tore down this motor before to fix a bent valve and threw it back together without fixing this.  You can see piston #3 has an indentation from an intake valve.  When I changed the valve stems I inspected the valve and it looked straight.


I've had some time to work on the bike the last few days.  I cleaned up the pistons real nice and installed the new rings.  I lucked out and all the ring end gaps were within spec and I didn't have to file them at all.   

[FGKouki]

I've started on the seat cushion as well.  I formed a pan from a sheet of 1/8" textured ABS and trimmed it so it's about 1/4" smaller than the outside edge of the tail section. 





I'll be using some rubberized closed cell foam (very dense) and some softer foam on top.  It will be about 2-3" thick with heat pleated black vinyl on the top and standard black vinyl around the edges.  This time I'm hoping for a more comfortable ride rather than a bare bones "it looks cool" pad.