1981 CB750K - Ruby - 90K km's

[shinyribs]

It's aftermarket Harley stuff. Not real clear,but I'd say,since it's Harley stuff,it's most likely for a 1'' bar.


Same part-different ad


A scratch on the valve face won't hurt a thing. As long as it's not at the very edge(where it could start ''burning''-but it'd have to be pretty deep to cause that)or on the sealing part of the vlave where it contacts the seat-you're fine.

As long as the hose ain't kinked I wouldn't sweat it. If it's bent super hard like you say,just watch it,and if it starts to fold/kink then you know you'll need to address it. Just my two cents,of course.


But good progress dude! Is it above freezing yet?

[seestheday]

It's been above freezing for the last few days.  Got up to +10 C for a while there during the day.

Now it's back to -6 C and snowing.

More progress updates.

Spent more time cleaning out the combustion chambers.  Got them almost as clean as I'd like.


Started to clean up the exhaust ports and found two sets of crush washers stuck in between layers of carbon and high temp gasket seal.  You can also see in that pic some of the progress I've made cleaning out the carbon from the exhaust ports.  It was previously very lumpy.  So much carbon it almost looked like there were stalactites in there.  Looking at this pic, I see that I really need to give the outside of the head a good wash again.  I might just get a big bucket and wash the whole thing in kerosene.



Note that I had already pulled one set out, so there were 3 that the PO put in there!  Kind of embarrassed that I didn't see them when I was trying to fix my exhaust leak issues before .
http://i1305.photobucket.com/albums/s546/simon_austin1/multiplecrushwashers_zpscfdf56df.jpg

Started to pull all the valves using my home-made valve spring compressor (basically an 8 inch C-clamp with a 1/2 inch pvc tube duct taped to one end and another one cut in a half moon on the other).  I'll post pics of the C-clamp later.

Lots of gunk behind the valves.  Sprayed it with deep creep and I'll clean it as best I can with rags and brushes, it doesn't seem too baked on.


When I pull the rubber valves seals off of the valve guides they are just disintegrating.  One has broken in half, all of the others are badly deforming & cracking when I pull them off.  I will be replacing all of these with the viton seals.  Highly recommended by the CBX, F and C guys.  Source is Jebby from the C, F & CBX sites if anyone needs them.  Something like $24 for a full set.

I've been checking everything for spec, and even though my B cam chain is past spec I've deciced to run it anyways because it seems to almost have no sideways bend.  I will keep an eye on it though, and it isn't too hard to switch this one out if I need to.  I don't even have to pull the engine out.  EDIT: it's not actually past spec - I just measured it wrong


Went home at lunch today and was greeted by some parts/tools I ordered .  Now that I have everything I need to lap the valves, I can keep charging hard at this.


How much progress I make over the next few nights will probably depend on how cold it gets during this cold snap.

[shinyribs]

Not trying to be a party pooper,but that b cam chain,if it's past spec does that mean its too long? So would that mean it wont fit the sprockets properly any longer?If the DOHC cranks are made like the SOHC the cam sprocket is made onto the crank. Damage that sprocket=ruined crank. Just thinking out loud,I guess.

[seestheday]

Turns out I measured it wrong. It's also the chain that joins one cam to another, not the one that goes to the crank. If it nuked it would still damage stuff, but not as bad as the A chain if it went. I'll be measuring it again soon, but I suspect it's within spec.                                                                                                                                  

[seestheday]

No real updates this week.  It's been too damn cold, -10 C or colder most nights.  I managed to get all of the valves out and clean the head up quite a bit more.  First with a solvent scrub, then a good wash with soap/water.

BTW - there are washers under where the springs touch the valve guides.  I didn't know this before the soap/water bath. Good thing I have good eyes and didn't lose any .

It's warmed up to -5 C now and might be as warm as -1 C this weekend so I'll be able to make some more progress.

I was hoping to clean off the tops of the pistons with just a brass wire wheel and not pull the cylinders, but after doing some cleaning I ended up with little brass wires along the edge of the pistons that I can't seem to get out.  I guess I didn't think that through and will be pulling the cylinder.  I'm not planing on pulling the pistons though, because I definitely want to stop at that point.

Still need to inspect the oil pump.  Hoping that it is in good shape because I believe they're NLA and a pain to find good ones used.

[seestheday]

A few updates.

So, it turns out that the cams I got aren't 900 cams at all.  They're 1983 cb1100F cams .  I found out that 1100F cams are worth significantly more, and contacted the guy who sold them to me.  He made a mistake and I'll be swinging by tomorrow to pick up the real 900 cams, along with a set of old 900F rear shocks (with fancy external oil reservoirs).  Not sure how much better they'll be than my stock shocks, but at least they'll look a little cooler.

The 1100F cams could work, but only with piston indents, stiffer valve springs, and taking a little bit of metal out of the head with a dremel.  I'm not really into doing that much work.  This isn't a race bike I'm building.

I'm currently waiting on the viton valve seals to come in the mail, so I'm not rushing on the valve lapping.  I plan on starting that tomorrow.

I decided to check the oil pump, and found some nice frozen oily water in the bottom of the chamber for the dip stick.  Makes sense that I'd find it considering the mayonnaise I found behind the left side engine cover.  I will have to figure out how to get all of that out of there without splitting the case.

I am am also struggling with getting the cover off.  I've removed all of the bolts, pulled on it, pushed on it from the side, tapped it with a deadblow, and it is not moving.  I'm off to buy a heat gun tomorrow.  I'm guessing that there is some ice buildup .



I also put some new signal lights on because I hated the enormous cheap plastic stock lights.



Only problem now is that my taillight now looks enormous...

I got the rear lights on by cutting/grinding off the stock signal tab on the grab rail and mounting them onto a hole in that was previously used to run the lights wires through.

On the front of the bike I'd like to change the lights as well.  Any ideas on how to easily mount them?  Note that I don't have welding equipment.  Are there clamps that can be used?

Pic of the stock tab:

[shinyribs]

That's mighty honest of you on that cam deal Prof. Sees! Good on ya man.

And piggy back shocks do look cool

[Johnnylevi]

Hey sees, for my front turn signals I just got the ones like you have in the rear and put them where those reflectors used to be. So, the turn signals hold the headlight bucket in place.  I'll try and get pics up tonight sometime.

[seestheday]

Hmm... looks like a common solution is to put some brackets on the headlight ears.  I'm still interested in a way to put them down lower, but the brackets might work.

[shinyribs]

seestheday wrote

 I'm off to buy a heat gun tomorrow.  I'm guessing that there is some ice buildup .

You're an animal...

[seestheday]

Oh, good idea. I didn't think the threads would match, but I guess even if they don't I can grab a different nut.
         

[seestheday]

Never once crossed my mind to take advantage. I live my life that way and it has always worked out better for me. I have been very fortunate, pass it on when I can, and find that the more i do the more it keeps coming back to me.

[Piute]

seestheday wrote

Never once crossed my mind to take advantage. I live my life that way and it has always worked out better for me. I have been very fortunate, pass it on when I can, and find that the more i do the more it keeps coming back to me.

                   Good Man

[seestheday]

Ok, more updates.

I installed a new speedometer cable, new tachometer cable, and a new choke cable.  My choke cable wasn't working ideally, and I'm hoping that the new tach and speedo cables will remove some vibration I'm seeing in my gauges.  Next step is custom gauges, but that will likely need to wait until at least the summer (I'm assuming they are going to be much easier to bolt on than the engine work that I'm doing now).

I also installed the new front signal lights.  Thanks for the idea Johnnylevi


Note that I am planning on grinding off the old tabs and then painting the mount.  Still haven't decided on a colour scheme.  Might add a bright red accent there?  I'm thinking I should paint the tank and side panels a shiney black and have various bright red accents.  Still pondering this.

After using the heat gun on the oil pump for a while I finally got it off.  I'm very happy to report that it is in almost pristine condition.  I don't know why I was so worried about it.


Now I don't think the oil pump has ever been inspected before, because that damn old gasket was a massive hassle to get off.  It also looked like it was leaking, so I'm happy I replaced it.  The gasket remover spray I used had some instructions that were almost comical.  "Spray, let sit for 5-10 min, and then remove gasket with a plastic putty scraper".  With a 32 year old baked on gasket it was more like: "spray, wait 10 min, use wire wheel in a drill to take off the top layer, spray some more, wait 10 min, use a brass wheel to take it down deeper close to the metal, realize that you're wearing out the brass wheel, spray some more, switch to a nylon wheel, use that to take down even more, spray, repeat, spray, repeat....".  I finally cleaned it up so I'll get a good seal though.

Pic of the finished product.


Brand new gasket


I also re-installed the gasket, & oil pump, then cleaned the cover and put it back on as well.  I will probably give the whole area a power wash before putting it all back together.  Lots of road grime gets in there.  I'll just need to make sure to check the seals and replace any that need it.

Next up - lap the valves, followed by putting the head completely back together, then pulling the cylinder to properly clean the piston heads and cylinders.

[free2ride]

alright, there is no doubt about it, you . . . tools . . . shiney . . . cda . . . Piute . . . the Sarge . . . OK, just about everybody here amazes me and makes me feel pretty much useless. I have no shop, no garage, and no mechanical sense. i take my bike in to a mechanic and he tells me what needs to be done and does it and I just fork over the $$$.

so I stand in awe of all of you. hope to see the bike this summer as I ride by.

[seestheday]

Thanks for the compliment free2ride, but don't be too hard on yourself if you don't have a place to work on your bike. What you also don't see from my posts is how much time I've had to spend to get as far as I have. I feel like I am going super slow, because I don't know what I'm doing. I feel a little bit like I'm on a deadline because this is my primary vehicle. I think that if I had the choice I wouldn't do this again unless it was on a second bike so I could do it more casually.

[easyrider12]

Hi sees, when you fixed your starter  clutch, what shape were your caps and rollers in?  A rebuild kit is $30 as opposed to just picking up a few springs for a few dollars.  I'm just doing up a parts  order list and its too cold to get at the bike.  No biggie either way,  thanks  EZ

[seestheday]

Mine showed no signs of wear.  They were in surprisingly good shape.

[Piute]

   THX. ya just remined me to lube my chain
                             Done

[seestheday]

Took a few days off, but got back out again last night.  Not a huge amount of progress, but I did lap the first 4 valves in the 1st combustion chamber.  I went fairly slowly taking my time because it's my first time.  I had a ton of carbon buildup on the exhaust ports, but I am worried about taking too much off and putting them out of shim range.  I guess I'll have to see how this goes.