Topic: UnCrash's slow but determined CB750F3 Cafe Build

[UnCrash]

With temperatures in the low 40's this evening indicating a true "January Thaw", I kissed my wife goodnight at 8pm and headed out to the garage to start progress on my 750F3 cafe build.   

I put 2,500 miles on this bike last riding season after resurrecting its mechanical condition.  I'm determined this year to improve its aesthetic  condition, which is currently non-existent. So, tonight I started this project like most do with cans of beer and good intentions.

Accomplishments tonight were:

• Remove Vetter fairing
• Remove exhaust
• Remove handlebars and controlls (ok some controlls are dangling but at  least the handlebars are off!
• Remove rear fender, inner fender, rear turnsignals, and seat.  Unfortunately, I managed to shear the left side bolt off the rear outer fender shock mount
• mocking up seat lenghts so that I could create a seat pan if needed

[FunJimmy]

Admirable!

What better way to begin? Beer in hand!

Don’t forget tomorrow too.

Cheers
FJ

[andy750]

Good for you Ben! Looking forward to more of your updates and photos! Dont forget the photos! Im eager to see what you are going to do with your bikes. God luck!

 I was hoping to get in my garage tonight as well now that temps are "thawing"...I have a new Ebay set of CB1100F shocks to put on the cafe K2 and replace the leaking oil pan with a non-leaky one....then Saturday pull the K4 engine to give to Mike.....never ends 

cheers
Andy

[azuredesign]

Hey Ben,

I'm looking forward to seeing the completed version when we both show up for one of the local rides. I guess you predated my involvement, and the other guys speak highly of you. In the meantime, if there's anything I can do to help, let me know.

Ben

[UnCrash]

Thanks for the encouraging words mate.

I made a couple hours of progress tonight as well which started with me on the hunt for batteries for my camera which I never found....  I know you like pictures.... Well I like them too, especially when trying to remember how things go back together.

Tonights accomplishments:

• Removed right side peg & rear master cylinder aluminum mount along with rear MC
• Hacksawed rear seat pan and foam in the first steps of making a solo seat
• Lots of eyeballing seat, rear cowl, and fender lines to get my mockup right
• Pulled apart the ratsnest of wiring that was in a bag behind the Windjammer fairing (got a strong sinking feeling) and started labeling stuff
• Took many sips of Yeungling Lager
• Still believe that I'm doing the right thing pulling this old bike apart and rebuilding it

[azuredesign]

The wiring looks much more daunting than it really is. The colorcoding should be fairly intact, but if not it's pretty easy to figure out what goes where, although it never hurts to have a cheap multimeter to check for voltage and impedence when the obvious is not so... obvious. It'll feel good when the fairing comes off. The cool thing to remember is if you make a mistake with a part, $10 bucks and a little browsing will replace it! Keep on going,
Ben

[S-Dog]

Yesterday made me happy that I didnt take apart my bike.  Its good to see that you are going to give that bike a little TLC.  It wasnt much to look at but on our jaunt up to Owls Head it sure was a screamer.  I look forward to see all the ideas you had in the summer come to fruition.


Scott

[UnCrash]

Hey, whadda ya know I was able to recharge some batteries, post some photos to photobucket and again make progress tonight.

Here's the progress I made:

• here's the seat mockup photo
  
• attached these funky rearsets that I purchased to see if they fit. 
   
• Whaddya know they work perfectly 
  
• These new style wrenches Rock!!!
  
• Removed toolbox and battery tray
• Removed Air Filter Box and carbs
• Removed Oil Tank
• Labeled, labeled, & labeled lots of bits, hoses, & bags
• Final Result
  

I'm loving this January Thaw!  It's been over 50 F for 4 straight days and I still have more than 6 inches of snow left on the ground in my yard.  At least my driveway's almost clear...

It will be warm enough for the next few nights to be out in the garage.  At least now I have parts to work on in the basement.

[Otto]

Looking good Ben. Are those the handlebars from the 74?

See you Sunday.

I have some more parts for you too!

bc

[azuredesign]

Hey Ben,
Do you know what those rear sets are off of?
Thanks!

[UnCrash]

Hey Otto 

Looking good Ben. Are those the handlebars from the 74?

Yes, they are!  They look dandy on there.  I'll try them out for a while.  See you Sunday at 10:00!

Hey Ben

Do you know what those rear sets are off of?

  They came off a 74 CB750 that was cafe'd long ago.  There are no markings on them.  They have a funky plastiky coating and unusual mounts...  Any one else on here know about these things???

[andy750]

Hey Ben,
Its looking like you are making some progress! Your bike is looking much sleeker without the fairing! So what are the plans with the carbs off? Rebuild carbs? Are you removing the engine? Exhaust - will it fit with rearsets? Are you going to paint? Whats the plan!? 

cheers
Andy

[UnCrash]

Hey Ben,
Its looking like you are making some progress! Your bike is looking much sleeker without the fairing! So what are the plans with the carbs off? Rebuild carbs? Are you removing the engine? Exhaust - will it fit with rearsets? Are you going to paint? Whats the plan!? 

cheers
Andy

Hey Andy,

I put the carbs inside a couple plastic bags to keep the vermin out.  This old girl ran so good last year that I don't think I need to do anything to them but do a little external cleaning.  If I need to get into them, I'll leave it until after the bike rebuild is complete, and address them if they become an issue.

I'm pulling the Engine.  You've made it sound like so much fun that I have to try it too!  I'll give it a good look especially examining the exhaust valves and guides.  As has been posted around tho, many of these bikes received factory service early in their lives to address this fault.  I'm hoping that's the case with mine.  If they need replacing, I'll be talking to Mike about a mild port and polish as well.  The main reason for pulling the engine is to paint it and the frame.

Good thought about the rearset / exhaust interference potential.  I'll have to look at that.  These were on a bike with a 4 into 1 so I have hopes. 

I hope to paint everything!  I'm speaking at a conference this April, for which my company should give me an "Author Encouragement Award"  It's pretty minor $$$ but it could finance a powdercoating.  I know that's the way to go but I'm on a austere budget with this rebuild.

Currently I'm thinking black frame and swingarm, deep red sidecovers, tank and tail.  The tank and tail will have a 3" black center stripe following the lines existing in the 750F tank flanked by a slightly off-white pinstripe.  That's the thought for now anyway.  I'll be doing some photoshopping to visualize it better.  I would also love to powdercoat the wheels black. 

Thanks for the encouragement.  Any ideas are welcome.

[andy750]

Hi Ben,

Yeah I agree with you on the carbs - your bike did run very well last year so I wouldnt touch them unless you want to check the jets for any gunk.

Oh yeah pulling the motor is so much fun  Actually its not too bad and it is interesting to open it up and see whats going on. Certainly an experience. I think you should get the port and polish in any case - made a big difference for me! More power!!! Its so seductive 

Good idea on the painting and I know what you mean about the tight budget. I like your red paint/white strip idea - get on with the photoshop and see how it looks! Only thing Id change with the colour scheme is see how painting the frame/swingarm grey/aluminium would look - the red and grey would really offset each other - see FunJimmys bike with the yellow tank/grey frame (in his avatar) - I think this looks really good. Everyone does black frames  Of course I should follow my own advice but Im too cheap/lazy to go to all that prep work to paint my frame....maybe some day. I need to paint my tank/sidecovers first.....

Good luck with it all and keep those updates coming...between you, Ben (Azuredesign) and myself we are all going to Mike for some headwork this winter....

cheers
Andy

[UnCrash]

Only thing Id change with the colour scheme is see how painting the frame/swingarm grey/aluminium would look - the red and grey would really offset each other

I agree Andy that a gray look on the frame could be good.  MikeB4 did that on his swingarm and I think it looks great -->

Maybe I'll play with those ideas in Photoshop as well.

Cheers 

[UnCrash]

More progress was made this evening in preparation of pulling the engine:

• Coils removed
• Motor mounts removed
• Rear tire removed
• Chain removed
• All electronics in the rear wiring harness area disconnected and labaled
• Oli filter housing bolt sheared off 
• Cam tower cover removed

Now, I have to get that damn oil filter housing bolt off somehow.  I know I'm not the only one this has happened to.  There's enough showing right now that I may be able to vice grip it.  Otherwise, looks like I'll need to get it to someone who can weld something onto the end so it can be turned.

I purchased some marine vinyl and sewing thread from JoAnn fabrics today for $11.00 total.  That leaves me enough to screw up the first time and have enough to sew up another seat!

They're forecasting that the end of this "January Thaw" will be coming.  At least many of the parts can be carried down to my basement.

[andy750]

I saw the forecast last night - supposed to snow by Monday  Garage time for me last night - pulled the oil pan on the K2 to replace it....will finish off that job and re-install exhaust, change rear shocks on Saturday morning (43F).....

As for your oil filter bolt - good excuse to get  a new 17mm bolt from Dennis Kirk/JC Whitney etc....in meantime either vice grip away or use saw to cut nut in half and wedge a screwdriver in their. However vice grips with extension on handle for leverage should work.

Good luck!
Andy

[UnCrash]

Well I wrestled more with that pesky oil filter bolt. 

I came to find that what sheared off on me was actually a nut welded onto the end of the oil filter bolt! It was a pretty good job and I never noticed when I changed the filter for the (only) time last spring.

I couldn't get that thing off, or get something clamped on to it.  I tried to drill the bolt out, but after 30 minutes of that I got too annoyed with the whole ordeal, and confirmed that I have a spare oil filter housing in the garage. Since I did, I got out the reciprocating saw and went to work.

2 blades later and it was off the bike 



Since I needed to make some progress on my kitchen renovation this weekend, I cinched up the handlebars and wheelbarrowed the bike out of the garage to make some space for milling trim.



My brother in law is coming over tomorrow morning and we're going to pick up Otto's 76 parts bike so he can build a bobber out of it.  While he's here I'll see if I can talk him into helping me get that engine out.

I couldn't believe the amount of crud around the forward sprocket!

I'm really looking forward to having a clean bike.  I don't think this one has had a cleanup in the last 10 years.

[UnCrash]

My brother-in-law Marcus came over today as he was picking up a 76 750K "parts bike" from Otto (on this forum).  Marcus is a great artist and runs "Just Good Tattoos" in Portland Maine (http://www.justgoodtattoos.com).  He plans on building a hard tail bobber with the 76.

While he was here I talked him into helping me hump the engine out of my build bike.  It's amazing how much easier it is with two people.  Man, that engine is full o gunk!  Shy of carting if off to the pressure washer at the local car wash what's the best way to de-crud it?  I was going to start in with Simple Green and a toothbrush...  The space between the engine fins looks like a particularly challenging area.  Has anyone just taken this to a prep place for media blasting?  I plan on painting it with some VHF product...

Those finned sidecovers came my way thanks to Otto.  I'll be polishing them up and painting the cases black again.



Many folks on here mention grinding down a tab on an enging mount.  I suspect that it's the one in the circle but would love some direct acknowledgement from someone that's done this before.



Once I get everything removed from the frame, what are the necessary next steps to prep it for painting?  I've noticed posts acknowledging that builders finish or clean up some welds.  What does that mean?  Is it really necessary?  I'm leaving my sidecovers on along with the oil tank and air filter so I don't think I'll need to grind any tabs off...

My goal is to clean up this old bike.  It ran great before teardown but wasn't very pretty. 

Any thoughs would be appreciated.

Thanks!

[UnCrash]

Well, I made my way out to the garage tonight in hopes of making some progress.  My thermometer outside the house showed 28 degrees (farenheit) but it was definately a bit colder inside the garage.

Nevertheless, I pulled the tab on a fresh Labatt's blue and got to work on the seat.  I trimmed my stock seat pan and cowling from the 78 750F and removed about 3" of material between the pan and plastic end.  More work to go.  But my toes told me to get the hell out of there after an hour and a half.

Regardless of outcome or extent, progress makes me feel better.  I can't bear to be without my main ride for long.

Additionally if anyone reading this blog has thoughts on my current problem:

I broke the end of the shock mount bolt off when trying to remove the nut.  The end of the bolt just spun right off with the nut.  Would anyone have any recommendations on what to do??? Do I cut off the shock mount bolt, drill it out and put a new (non-welded to frame) one back in?

Any one else have to deal with this bugger?

Cheers,

Ben

[FunJimmy]

Ben

When the shock mount nut spun off, did it leave behind the mounting shaft?
You know the smooth part that fits inside the shock bushing.
If it did, than all you need is a fastener to ensure the shock doesn't slip off the end. Right?

Could you drill the centre of that shock shaft and tap it for a m6 bolt?

Perhaps a picture.

[andy750]

Hey Ben,

This ones near you....pricey but perhaps you know him?

http://boston.craigslist.org/gbs/mcy/547758547.html

cheers
Andy

[UnCrash]

Hey Andy,

Well Portland's mighty small for a state's largest city, so he's no more than 2 miles from me...  I love his quote "Just in time for summer ride"  He must be in some kind of time warp.  The bike looks realtively minty, but it's always hard to tell via pictures.  I don't know the bloke, and haven't seen the bike around.

If anyone's interested I can give it a look over for them...

Funjimmy thanks for the thoughts.  Yes there is about 1/2 inch of thread left exposed before the bolt descends into the mounting shaft which offsets the shock from the frame.  Plenty of room to do something with. 

than all you need is a fastener to ensure the shock doesn't slip off the end. Right?

Yes, that's absolutely accurate.

Could you drill the centre of that shock shaft and tap it for a m6 bolt?

I could definately do that.  Looks like the best way to go.  Thanks for the suggestion, it is much appreciated.

-Cheers

[UnCrash]

I made some more progress last night.

MikeR posted on another thread a recommendation to remove the exhaust studs to make engine removal easier.  So I started there.  I got all but the outside 2 out.  This will definately make it easier to get the engine back in   

I hacked and pounded away on my cafe seat.

Here's the progress on that front:




I've hacked about 3.5 inches out of the stock 750F pan and am shaping the two sections together.  I'll then rivet the hell out of them as I don't have a welder.  The stock rear cowling will stay but I'll embed a tail light into it and get rid of the big honking stock one.


Here's a shot of where the bike is so far:



I'll be cleaning up the frame and spray painting it.  I've got to figure something out about that though, most paints want to be applied at 70 degrees.  We won't see 70 for another 4 months here in Maine and I can't wait that long.  If I could haul it down to the basement I would...  Maybe I can find a place locally to do it.

I'll continue to pound away on the seat until I finish that.  Then I'm off to the tank.  Making knee dents is appealing but for now I think I'll just fix a couple small dings in it a re-spray.

[Otto]

Looking good Ben.

I keep telling myself it'll be warm soon also!

BTW,

The 74 750K4 will be completed this week too!

bc