The Humpty Bike - Putting it back together again

[kauai1800]

Thanks bikeymikey - yeah rust never ever sleeps here on Kauai. These are being prepped for VHT primer and VHT black paint and I plan to paint em in the next few days. Waiting for the paint to come in at NAPA. I think the pipes will look pretty sick all black. I'm not worried about the paint being perfect - it'll just be for use.

I'm gonna work on cleaning up the exhaust, rehabbing the brakes and assessing what's missing. I'm going to Vegas next week and I want to wait til I get back to get in too deep on the motor.

And I spoke with Louis who convinced me that if the bottom end on a school bike had ever been opened I needed to have a look to make sure there's no gum wrappers, pull tabs, etc in the crankcase. So that's the plan - doesn't seem like it's too terribly hard to just open it up and have a look. I'll ospho the con rods while I'm at it.

Ah yes Harbor Freight - we don't have them here. So no buying something cheap. We got Home Depot, Oreilly's, NAPA, Walmart, Sears, and Kmart. That's it.

For media blasting there is a guy here to do that. If Mike can't swing me some rotors I'll send these to trudisk. I'm not going to sweat the rust on the inside of these rotors if I end up using them. They'll be staying dry from now on - I hate riding in the rain.

[daves79x]

Good luck with your project - agree with most suggestions given you so far. You needn't go to Vegas - we just got back from there and brought all the money home with us!

Dave

[kauai1800]

First off, I have to send a HUGE MAHALO out to Nils - as I opened the mailbox on Saturday to find the 6 exhaust collars that he sent me! YOU ROCK!! They're in nicer shape that pretty much anything else on the bike!

Despite being active on several MC forums, this is the first time anyone has sent me anything..let alone for free! And Mike offered brake rotors but in the end he didn't have the ones I need...but still....so nice.

So I'm really impressed by the CBX community! The guys at CBX World are really being helpful as well, so I'm feeling pretty confident about the Humpty Bike...it WILL run again!

Also in my poking around, I found the 6 copper "rings" that fit between the exhaust and the head..so I think I have most of the bits for that install now. Still waiting for the VHT primer to come in so I can paint the exhaust..

Gonna pull the wheels off in the next day or so, and then it'll really be a "frame off" restoration...though I'm not planning to tear the frame all the way down. The wiring harness and Prolink are things I'd like to leave as-is unless I detect a problem with them later on. Can anyone tell me if the rubber "dampeners" inside the wheels are likely to be in OK shape?

I have repainted/rehabbed the instrument cluster, the chain guard, the brake protector caps, plus removed the rust from the frame...so it's looking much better. Lots of black "wrinkle" paint like an old school bomber...in fact there might be a design theme in there somewhere...a CBX-meets-B2 bomber vibe maybe?
Nothing like that all aluminum "faceted" CBX I've seen....more like a bike based on one of my favorite places...Groom Lake...aka Area 51. We'll see what I come up with.

Anyway, Nils, your karma score went through the roof!

[NobleHops]

Hey, my pleasure, no worries. My bike has more than a few pieces that were given to me by other CBXers, or worked-on by them, etc etc. Yes, this is a great community including the gang at CBXWorld. If you're putting one back on the road and will share your journey with us, we all will generally want to help, ESPECIALLY if you post photos and your account. That's good fun.

WRT the dampers, here's my take. I recently pulled my dampers out of my 10 year old VStrom and found that the drive side was compressed a full 3mm in size from the new ones, and also as compared to the 'undriven' side. That resulted in a ton of sprocket carrier play. If yours are 6 miles old and there isn't a lot of play between the sprocket carrier and the hub, I'd say you can safely use them, but you will not be getting as much shock absorption out of them as a nice soft new set. I don't personally think there's much risk in trying it, and making up your mind later, as long as they haven't shrunken and introduced a lot of play.

Unless you have them you still need those flanges for the exhaust - two per header pipe, they are semi-circular and L-shaped, if that's not impossible to picture. Check the fiche. Louis will have them by the bushel if you don't. I'd start there if you find you need them and nobody else pipes (get it?) up.

Onto your brakes, those will need a full strip and inspection, and you will need seals at the least, but I would not be surprised if you ended up needing pistons too. Are you into them yet? The K&L kits include all the rubber bits and rebuild parts including the seals, but NOT including the pistons, which can be found more inexpensively at a few places including eBay. Some guys favor OEM seals from their experience with them all.

Photos man! Where are the photos!

N.

[kauai1800]

Yeah the brakes are in pretty bad shape. The rear looks like it will only need a little love..but one of the fronts will need a full rebuild and one is basically just the caliper...no pistons at all. I found a matching pair on nice fresh-looking ones on eBay and nabbed them. They look to be in near perfect shape - the ones I have would've needed 2x pistons+ 2x rebuild kits meaning that each one would cost about $90 to rebuild...I only hope these new ones don't need to be rebuilt .
Thanks for the info about the Comstar dampers.

I am going to open the crankcase up and have a look inside next week. The service manual says that you can open it without having to remove the clutch, the generator, starter, etc. and that's what I really want to do. The manual says that the risk of opening the crankcase without removing those parts is "the transmission gears may be dropped when separating the crankcase". Can anyone comment on this? I think they mean because you might have the crankcase on an engine stand the gears might fall out? I have no stand, so mine will be propped up using lumber or something. Seems like the gears would just stay in the top half of the case with the crankshaft if you open it level.

The reason I want to leave the clutch etc attached to to reduce the risk that I screw something else up during re-assembly. I'm looking at the instructions and every piece that is not taken out is one less one I can screw up. I have never gone this deep into an engine before. Because this bike is in pieces, I'm already missing plenty of hardware and have parts I can't ID. So this is tough enough already without me creating new problems.

[daves79x]

I know the manual says all that, but you really need to remove all the heavy, external stuff you can - especially if the engine is not on a stand. You never know which half of the case the countershaft will stick to and the clutch weighing down one end of the main shaft won't help. You will need the special socket to get the clutch off, but it really needs done. Once inside, since nothing in there will be familiar to you, you really need to follow the manual carefully. If you plan on removing the rods for cleaning, extreme care is needed there. My gut says that if you can get a friend that's got a little experience to help, you'd feel more confident about it. I know you've said that ultimately you don't have much to lose here, but from what I can see, this bike should be able to be put back together in running order. Good luck and if you need help, even step-by-step with the cases, just shout.

Dave

[kauai1800]

Thanks for the nice reply Dave. I agree with you but sadly I don't know anyone here personally who can help me with this. There's a couple bike mechanics but they get $80 hr and neither will do it for cheaper if I help or they use my tools etc. in fact they won't allow me to help. There's a couple other guys who I'm going to call and maybe they can help me out for less money. I'm just trying to avoid spending $500-800 to have the crank back up to snuff. If i need new con rods this is gonna turn pricey fast. But in the other hand it needs to be done right and I realize this is going to cost something...just trying to only spend $$ when it's beyond my skill level and this might be it.

(update)
Well I just got off the phone with what is perhaps the best motorcycle mechanic on the island...an guy from Oz. Ironically he said he'd just helped a guy put a CBX together here on Kauai. I told him the situation and he basically told me that unless I wanted to spend $2500+ to have the motor rebuilt - that his suggestion is to part it out and make some $$. He estimated 12-15 hours for the crankcase alone...so over $1K. That doesn't seem unreasonable, but that's not something I can afford to do.
He also re-iterated Louis' concern that because it's a school bike "the motor had been apart 17 times and every bolt in there is stripped" (said in a good Ozzie accent). I think my motor might not have been so mistreated - as the crankcase bolts look like they've maybe been opened either once or never - and I looked using a 4x Optivisor.

He had to run before I got the name of Kauai's other CBXer..but I'll try and get his contact info soon..apparently he's looking for a stock exhaust for his CBX
I'm surprised he's not on the forums...

[cbx6ss]

Welcome to the forum!!

Believe in yourself and the collective wisdom, experience, and helpfulness on this forum. You can restore your bike yourself! This forum could talk my wife thru a rebuild!! Don't part the bike out!!

I unexpectedly and abruptly modified my 81 a few months ago... Now that I can spin wrenches again, I dove in last weekend. This is the second time around for a frame off for this bike, but this time the starter clutch slipping was so annoying, I couldn't stand it anymore, so I tore the lower end down. Here is my bike as of tonight.



A couple quick links:
Gasket set 75.00
http://www.ebay.com/itm/230565359405?ss ... 1497.l2649

Seal Set 25.00
http://www.ebay.com/itm/110992525758?ss ... 1497.l2649

My Cafe project is back on. Phase 1 got a debut at Saluda 6/11...


Phase 2 is next...
viewtopic.php?f=102&t=6939&start=30
/r,
Brad

[kauai1800]

Thanks Brad. That was the most emoticons anyone's ever used to reply to me!

Nah I'm not gonna part the bike out. With all the nice folk around here willing to help the least I can do is try. I'm off to Vegas for a week or so; we'll get this party started after that.

[cbx6ss]

Here's some inspiration...

http://www.digitalpizza.com/1979%20Hond ... %20CBX.htm

One bite at a time...
/r
Brad

[kauai1800]

Aloha,

A little update - I've been smiled on by the cbx gods and master-wrencher Herdygerdy is coming to Kauai on vacation from Oz and plans to spend a couple days helping getting the motor running.
He's rebuilt a couple CBX and knows all those "little things"
I'm chuffed! (that's like being stoked, ya?).

So my next action is not to clean the carbs, not to clean the cylinders, not to clean the valve cover - but to clean the friggin GARAGE! so we can have a decent place to work. In Hawaii space is at a premium, houses and garages are typically small, and we usually work on our bikes and cars just sitting outside. Our solution to sun/rain/torrential downpour is to pop open a 8'x8' shade canopy (and a couple beers) and keep plugging away. But rather than subject him to our third-world ways, I'm going to see if I can actually create a space to work in there, rather than just a place to put things.

In other news got one of the 2 pipes primered with VHT paint...waiting for another can of paint to do the R side. Looking like I'm not missing anything major that will impede this bike going back together again.

I still can't believe how unbelievably generous the CBX Community has been. Nils sent exhaust collars, and a secret friend sent me 3 brake rotors that are currently being honed at truedisk, and I sold enough cookies this week to buy 2x front brake calipers on eBay that are in much better shape than the ones I had - these will get new seals and pads.

OK time to clean...

[NobleHops]

...that's the way my bike got put together - with a little help from my friends here and there

[kauai1800]

Plugging away over here...
Got new gas cap, new battery, new oil filter, and some new handgrips. Got all kine stuff ordered from Louis. Brake rotors coming back from Truedisk and new-ish front calipers in hand.
I'm getting close to having assembled all the parts needed to at least get the motor running and the brakes working. I've been cleaning and sorting and reading a lot lately.

I realized that there probably not many guys who've built up a basket case CBX before they've actually seen a running CBX in person...which I never have. So if we getting it running it'll be even more cool cuz not only will it be my first major engine build - it'll be a CBX when it's done!
Glad I'll be getting some help though.

OK back to reading...

[steve murdoch icoa #5322]

You said it, brother!
Ownership is great but the feeling you will get when you go for your first ride on a bike that you restored can't be beat.

[CopperCollar]

Glad you got all kine stuff John.
Can't wait to see the finished product.

Let me know what you think if the Tru-Disk work.

Mike