Topic: CB 750 AMEN Chopper

[Anglo]

The 4 bolts under the rubber pucks are the only thing still holding the head onto the cylinders. I checked, each one is a hex head


I went through a few hardware stores for a thinner piece, but the one I bought is still too wide  Is it worth sanding down the sides of the piece? is there another trick to getting the bolts out?

Bonus picture,  there are 6 pucks and 4 bolts. Under another one of the pucks? A mummified wasp! Lord knows how long its been in there, its kind of funny to think its been sat there mummifying every time the engines been running. A wasp in an engine... thats a first for me!

[Terry in Australia]

Yeah, it's interesting what you find mate, I bought a crashed 750 in 2009 and found the tach needle in the fins behind the cam chain adjuster, and large pieces of dried skin in various orifices. (The PO was only wearing jeans and he ground off both his kneecaps)

The bolt heads are 10mm, you might need to buy a cheap 1/4" socket set with thin walled sockets to get them out. They look a bit rusty, so use WD40 or whatever to help their removal.

[754]

 try 1/4 drive set , may be slimmer.

[Anglo]

So
A half hour round trip to the hardware store later I've got myself a 1/4'' 10mm piece. I took my socket piece to size it up, and it was maybe a millimetre or 2 thinner.


But it still didn't fit 


This is turning out to be quite the task. I'm looking around on different build forums and stuff to find advice, but theres not much reading material on it. A lot of people struggling to get the head and the cylinders apart, not so many struggling to get the bolts out.

[754]

Get a sander or grinder , and spin/turn it down.. They are not in real tight.
 Honda has T handle wrenches in their special tool list they probably use to remove. Whatever you put it in with use torque wrench.

[Medyo Bastos]

1/4" drive is what I use


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[754]

 I think we got to measure the ID and Depth of that hole...
 IF you dont have the means to measure the hole, try sticking sockets in there and then measure with a caliper...like .7** size socket wiggles a bit, but a .7** wont fit in hole.

Just checked a 73 head they dont have clearance issues, must be only on 72 and down.

[754]

I dont think that your camchain adjuster bolt is necessarily bent , it may be drilled at an angle to match the flat spot on the adjuster.. Then it wont walk as you tighten it..

[PeWe]

1/4'' 10mm socket of good quality has no problem to fit these bolts. Useful for the cam bolts and all M6 bolts keeping the cases together too.
I use Japanese Kamasa socket kits, 1/4" and another bigger1/2" socket kit.
Check the brand Gedore that has sockets of good quality and not thick as the cheap crap brands. Same with the wrenches, good quality brands have thinner and better tools.
German HAZET is good too. It cost not that much either. My torque wrenches and 27mm wrench I cut shorter for oil tank are Hazet.

Brand BACHO from Sweden has always had good tools of the thinner and durable quality. I have complete set of wrenches from 4mm to 28mm. I have grown up with that brand wrorking with bicycles, mopeds, my CB750 and cars.

[Anglo]

What're friends for aye?     

Lucky for me I've got a friend with a wardrobe sized tool collection. He came down with 7 10mm piecesand one of them fitted like a glove. On request, he bought a pry bar too. Once the bolts were out I thought the nightmare of removing the head from the cylinders would begin. While looking for help on getting the bolts out I found loads of posts attesting to heads getting stuck fast on the cylinders, but I'd also read getting it apart with a pry bar is pretty straight forward... A method I can attest to now! Less than 2 minutes with gentle (And seriously, gentle) application and it popped clean off.


Cylinders look good, I'll be booking them in to Rising Sun Motorcycles to get the bore tested as soon as they're available. The carbs have gone too, to a friend who's giving them the once over. The previous owner said he rebuilt them, and I've no reason to not believe him. Still, doesn't hurt to get a second opinion.

What next? Think I'll take the wheels and forks off. I know a guy who'll rebuild the forks for me, and I can get on with rebuilding the wheel hubs. While I'm doing that I'll get the triple trees, headset, rear fender and rear shocks off the bike and get to stripping and repainting the frame.

We're making progress folks, cheers for all the support thus far! 

[Anglo]

Okay update time.
Its wednesday tomorrow, my work day on the bike. Since I last posted the cylinders have gone to a machine shop along with the head to get the bore and compression tested. I think they will need to be honed, but the guy at the shop said they're the stock size and that theres no big gouges or anything, so we should be able to get away with boring out but 0.25mm (hopefully)

Anyhoo I'm not gonna know for certain till it gets back from the shop, which should be shortly before new year. So till then, I'm going to play around with the rest of the stuff on the bike. 

Plan for tomorrow is to strip everything off the frame so I can get the disgusting bathroom paint off it. My method of paint removal? I'll leave that to you guys



So I bought $26 worth of paint stripper, yellow plastic machetes and brass wire drill attachment for my corded drill. The question is; which is best?
I did a few tests




Paint came off pretty easy. Thats not rust by the way, thats brown paint underneath. Dark blue on top, light blue under that and thick brown under that. It makes you wonder... what this bike once was  Second layer of spray on death




Second spray took off all of the blue paint, but that brown stuff is tough as heck. So, I tried my other purchase on the other side




Works a lot quicker than the spray on stuff, but I'm nervous of scratching the frame. Taking the top coats off reveal that perhaps the light blue coat was painted over rust? Or at least some surface bubbling. What do you guys recommend?

[Anglo]

Bonus pic


I tried the brass brush piece on the fork.... Probably not the best idea 
The paint on the fork is just one coat, same coat as is on the frame. Makes me worry if the last guy was covering something... 

[754]

Check the brush with a magnet..some are just plated steel..

[Terry in Australia]

A good quality automotive paint stripper will remove that rattle can enamel lickety split mate, don't mess around with rattle can crap, get a nice gallon can of it and brush it on, leave it for a few minutes and it'll liquify the stuff to the point where a high pressure garden hose will blast off the old paint and keep your fingers with all the skin still on.

Obviously abrasive blasting is better still (no, not  soda blasting, that's good for cleaning carbs, but that's about it) but I've stripped several frames over the years with many coats of paint using automotive paint stripper, with excellent results. I hear a lot about "Aircraft Stripper", we can't get it here in Oz, but if it's available on your side of the pond use it, it's about the strongest chemical paint stripper available, I'm told. Cheers, Terry.

[stikman]

There are 2 aluminum oil jets with rubber o-rings around them in the spots I circled in red.  Pull the jets out and don't lose them (maybe set them aside in a ziplock bag).  Make sure they are cleaned out properly and look down the holes to make sure they are clean as well.  I'd also recommend cleaning off all the red silicone as well.

[calj737]

To Terry's point, a 1 gallon can of Aircraft Stripper (that's a brand) works best. You can buy at a local Home Center a variety of "citrus strippers" that will probably work as well. All chemical strippers are messy. They turn the paint to goo, leave it to you to scrape off, and you'll have to sand some spots afterwards. This method of manually removing the paint is very tedious.

Having the frame sand blasted is easiest and best. If you're near a marina, check with them as they might have a "dustless blaster" rig that is essentially sand blasting but the media is applied with a high pressure water stream, not air. It's used regularly on boat hulls. Fast, gentle, and often cheaper.

If you prefer to use an electric sander/grinder, 120 grit pads on an air grinder will buzz the paint off quickly. Switch to a Green ScotchBrite if you get close to the base metal or need some email sanding.

[Anglo]

Calj and Terry, I checked my local home depo and they said they couldn't get the brand stuff. Honestly, this spray on stuff isn't great, but I spent some money on it and I don't really want it to just take up space in the garage. If this stuff is gonna damage the frame I'll bin it, if its just gonna be ineffective... I'll squeeze my moneys worth out of it.

Stikman good shout, when I get the head back I'll take a look at them.

And lastly 754...

Bang on, as per usual. This is gonna be a bit much for the fork, but will it still be good to strip the frame? Perhaps if I'm gentle? 

Didn't upload last night cause my internet speed was really low, but I got the frame down as far as I could. I took looooads of photos, so I'll just pick a few. Front wheel off


I was just taking the chain off to get the rear wheel off when I noticed

Is that an okay thing to do? In my mind its a no, and I don't really understand why whoever did it did it. But that combined with the rust concedes the Chain and Sprockets to the bin, and a revised wish list to santa.

Some bathroom sealant holding the wiring in place on the rear fender


Bye Bye home-made wiring harness, you won't be missed

Forks off real easy


And thats as far as my tools can take me


The springs and the triple trees both need tools bigger than what I have. I'll borrow tools off someone soon, but everyones home with family at the moment. It may be a while. Till then I'm ordering a new wiring harness, some new condensors and sparks and stuff

[754]

Dont toss the harness, might need to copy it or use some ends.
Brush might. Not hurt forks..paint stripper might be quicker.
Triple trees come off easy once top nut is off, be prepared to catch the ball bearings, they roll all over.
Usually you tack in a piece of 3/8 brake tubing to the fender , to run the wires through.
 

[martin99]

Lots of progress there mate, good job. Looks cold where you are, probably helps to keep things moving along! I wouldn't worry about ordering a harness just yet, custom bikes usually require custom harnesses, and often with 'minimal' wiring, and anyway the wiring is one of the last jobs you'll do so you have plenty of time to think about it. Don't toss the old loom either, it might look a mess but it might also be your friend if you have to make a new one from scratch, at least someone has worked out what wires are needed and lengths etc. 

[martin99]

Looks like I hit the button same time as Frank, who gave you 6x the advice with 6x fewer words 

[stikman]

Here's a couple of really simple wiring diagrams for you.  No need to purchase a wiring harness.  When the time comes just pick up:

• a few rolls of different colored wire

• a basic connector kit

• a stripper/crimper tool

• a roll of electrical tape

and if you want to do it right, add in:

• a soldering iron

• solder

• shrink tubing

• a heat gun or lighter for the shrink tubing. 

Most all of that can be had for cheap at your local Princess Auto.





The second diagram comes courtesy of www.bellicomoto.com .

[calj737]

If you opt to use a grinder with a brush attachment to clean your forks, frame or cases, switch to a Stainless Steel wire. The Stainless will be much more gentle on the aluminum parts and actually remove the oxidation really well. Plus, it tends to hold together a bit better than Brass wheels which spinning at those speeds become little daggers! So do use some eye protection when wire wheeling.

Stainless wheels can be had in both "stiff" and "soft" weaves. The soft weave is my choice for working aluminum parts. Definitely don't use carbon steel wire as it will cause rust on anything metal you use it upon.

[Medyo Bastos]

you can use this as a guide for removing the springs on the rear ~>http://www.hondachopper.com/garage/savior_spring_removal/savior_springs_removal.pdf

the diagrams posted by stikman can all be viewed at http://www.hondachopper.com/main.html in the garage section.  you may as well sign up while you are there, and see if there is someone in your area, that can help you out. there are guys there that frequent here and vice versa.

just like frank said stock wiring harnesses are not used on choppers.  most build their own, and only run what they need.

[Anglo]

Okay guys,message received, I'll hold off getting any new wiring harness for now. I've put the old one to one side. Given the bike was running when I got it, theres probably a lot I can salvage from it.

Cheers Martin, The cold makes it a lot harder to convince myself into the un-insulated garage... 

Top diagrams Stikman, they're gonna come in handy. I'm glad to see one of them has signals... I'm not planning on a long tour without indicators. From everyone I've talked to travelling with a BC plate in America is like travelling with a big sign saying 'pull me over cops, my wallet is in my back pocket and you can have it' 

Calj steel brushes sounds good, as it turns out the brass wire one I bought actually is painted steel. Any decision that doesn't make me spend more money than I have to gets a big thumbs up from me.

Oki doki, I bought an adjustable wrench of the triple trees and big chrome nuts on the rear shocks. Off comes the trees


Headset bearings are looking cheery


Cones are looking good to


Trying to think of interesting things to say, but I'm not really a wordsmith... on to the rear springs! 
First thing to remove is the chain tensioners, but soon as I went to take one out I realised it was bent.


'No Worrys' I thought, I can replace that on the cheap. I apply a little pressure to get the bent nut out and...


The bolt thats supposed to be welded on came right off. Damn. And here I am with no welders in sight. Any hints on what I could fix it back into place with?

Got my adjustable wrench around the big chrome nuts (half expecting that to be censored by mods  )


I bought all the pieces for taking the springs out set up, only to learn the reason the previous owner hadn't bothered removing them. The Threads are cheesed!


They're so bad I assumed I'd got the wrong size threaded rod, but there was still a very small bit of thread at the bottom it just about gripped on to. Nowhere near enough to remove the springs though  Tap and dye? or another solution?

[754]

Your lower stem bearing, is it a snug fit on the stem.? Something not adding up there, do the bearings fit the races ? The reason I ask, two neck types on Amen. One takes harley taper bearings for 1 inch stem, but that lower bearing looks like it has a rubber seal like some Japan models . Lower tree looks like F model.
 If that thread is bodged, use a tap.
 You don't have to strip all that out, just get nuts off, mask and paint.
 Back to forks, you can get paint of with wire wheel if not too aggressive, and I was assuming sanding them out after stripping.. Paint stripper will get it off.
 
 Just realized its been 38 years since i put my Amen together the first time, and 34 since I sold it..!!