Topic: 1972 CB750 Four K2 -- Rebuilt to NEW OLD STOCK -- PIX ON PAGE 50

[Powderman]

If done correctly the wire wheel will just clean and polish the hardware and not remove any coating.

[edwardmorris]

@calj Thanks! So far no rusting back on the few pieces i've wire wheel cleaned. But I'm alarmed now, perhaps I should spray some WD-40 on them just in case. Don't have a media tumbler, and I don't want to throw it all in one place, I have it nicely bagged and tagged when I tore the bike down. Ideally something that would take the scrubbing part out of the equation would be great. I will try soaking a couple greasy threaded bolts in some CRC overnight to see if that gets it out.

@Powderman yes, the wire wheel seems to make the hardware shine a little, but I think the rust dissolver ate away what was left of the zinc. Most of the hardware, especially off the frame had a lot of white rust that seems to come off after a cleaning with mineral spirits and scrubbing with a wire brush/wheel. The bolts on the lower triple tree were the worst when it came to corrosion, with brake fluid and red rust rampant on the bolt heads and threads, probably should just replace these.

[calj737]

I think Dagersh has a thread where he documents his process for tumbling and keeping things organized. His factory hardware looks absolutely gorgeous afterwards!

[edwardmorris]

Here is a sample before and after. Soooo not worth the time and pain. Need to find a quicker way, tumbler might just be it..

[tweakin]

I used a tumbler when I built my CL360, worked great on all fasteners.  The one I used, http://www.harborfreight.com/5-lb-metal-vibrator-tumbler-67617.html#.UxauyeddWpo, was crazy loud.  Couldn't even be in the shop when it was running.  If I did it again I would go with the rotary tumbler like this:  http://www.harborfreight.com/dual-drum-rotary-rock-tumbler-67632.html#.UxavG-ddWpo.

i have a love-hate relationship with Harbor Freight tools, I call them disposable.   That being said I am sure others have more experience with various tumblers since I usually change out all fasteners for new stainless ones on my builds.

[edwardmorris]

... I usually change out all fasteners for new stainless ones on my builds....

I thought about that, but where do you get odd length bolts, especially for the triple tree like 56mm and 74mm in chrome? Even Honda doesn't have these anymore. DSS has a few 56s left, but no one seems to have the 74s. With chrome bolts, you gotta change the set or leave it, one or two shiny and the others rusty will irk me constantly 

[edwardmorris]

Sickness is keeping me from doing much. It warmed up to 40F today somehow so I stepped out into the front porch and treated some parts with Eastwood's rubberized rust encapsulator.

[Bill/BentON Racing]

I like Eastwoods stuff, Good quality, like there black chassis paint for stock frames.
I been under the weather also and waiting to gt a tooth pulled, root pain,ugh! Damn it's terrible, oh well I'll go look at new to me , CaveBears Webers!RIP. they look good!

[edwardmorris]

I like Eastwoods stuff, Good quality, like there black chassis paint for stock frames.
I been under the weather also and waiting to gt a tooth pulled, root pain,ugh! Damn it's terrible, oh well I'll go look at new to me , CaveBears Webers!RIP. they look good!

Ouch! Good luck to you sir, feel better.

I started a thread a while back to discuss stock frame color options and the unanimous opinion was that Rustolem Gloss Black was closest to period correct frame, and Rustoleum Semi Gloss was accurate for triple trees and gauges. Is Eastwood's color close as well?

[Terry in Australia]

Looking good Ed, as you've discovered, rust eater is usually phosphoric acid, which is great stuff for cleaning rust out of gas tanks and chrome rims, but no good for zinc plated nuts and bolts, spokes etc, as it eats zinc too.

Those bullet tumblers are great and with the right media will bring small parts up like new, but I just use my wire wheel on my bench grinder and spray 'em with some WD40 afterwards.

As far as stainless steel bolts go, they're fantastic and if you take your old bolts to a bolt shop, they'll be able to supply most of the ones you need. They may be longer than stock, but the good thing is you can shorten them to the correct length and polish the cut off ends if necessary, as unlike chrome or zinc plated bolts, they won't rust.

Otherwise, you can buy the repro "big 8" frame bolts from Yamiya. Not cheap, but nice.  Cheers, Terry.

[tweakin]

just saw this Ed, sorry for the delayed response.  Terry actually answered it well, most odd bolts were purchased from Yamiya all others were shortened if need be.

... I usually change out all fasteners for new stainless ones on my builds....

I thought about that, but where do you get odd length bolts, especially for the triple tree like 56mm and 74mm in chrome? Even Honda doesn't have these anymore. DSS has a few 56s left, but no one seems to have the 74s. With chrome bolts, you gotta change the set or leave it, one or two shiny and the others rusty will irk me constantly 

[edwardmorris]

Thanks Tige and Terry, I'll see what I can do. You're right about the phosphoric acid Terry, which makes me wonder if the Phosphoric Prep and Etch  sold here at home improvement stores can be used to treat gas tanks.

Weather is finally showing signs of improving but its still very moody. The cold and flu is finally gone but I'm trying to make up all the lost time at work. Should have some time tomorrow, but I can't think of what to get into. I'll figure it out, too much to do. Hopefully some updates soon.

[Bill/BentON Racing]

Yes to using it! cheap and easy. Heres some pics of what's coming your way!

another

All forks measured fine!

Should work fine.

other gears

Ready to ship!

Let me know,guys gear sets are $90.00 for C2&C5. Yes, I honored our original price on first set. Bill

[edwardmorris]

Sweet deal Bill, how much for the low mileage fork set?

Its been so long since I did anything substantial on the project, I was pent up, so I decided to take the most challenging task up till now, sanding down the rear wheel hub. This thing was atrocious looking with deep gouges from over tightened spokes. Pretty much took the whole day today. I've been doing the other pieces here and there for a while now as I made time. This is how they look after 500 grit. Not very happy with the clutch cover, will spend more time on that. Too many casting marks on the hub cover, being a nightmare, I might leave some in. Hub looks good at 500, next will be 1000 and 1200 then buffing time, trying to get all the sanding done first, this is painful.

[Kickstart]

Nice work!... and thanks for you post on my thread.

I'm leaving the casing marks on mine.  I think if you clean it up real good (I used those little sanding dremel bits - that "fingered" sanding spiral thing, and those brilopad like puffy discs) it looks pretty nice (and original). I'm just polishing the smooth surfaces.  I also have an F model where one side has a disc and the other the sprocket, so there's not much to see of the hub once everything is assembled

[edwardmorris]

Another (not so) long read from Hondaman/Mark about some of my novice questions related to polished transmission parts

http://forums.sohc4.net/index.php?topic=135295

[edwardmorris]

Cleaned up some more hardware and sprockets along with the splash guard. The splash guard had so much rust on it I pretty much was going to throw it away. Before doing that, I thought I'd give evaporust a try and wow did that work! Took three nights of soaking but ALL of the rust is gone and pitting shows. I cleaned it up well with a wire wheel cup on a dremel shaft and it looks like its ready to go back on. How do the sprockets look? Reuse or replace?

[Kickstart]

Looking good... I think I'll try the same with my splash guard.  Are you clear-coating it with something?

Replace the sprockets.  Always a good idea to replace the sprockets and chain at the same time.

[edwardmorris]

Thanks Chris, any recommendations? I don't think I saw OEM ones at motogrid but I haven't checked DSS and such just yet. I know Hondaman/Mark mentions in his book that the OEM ones were made of a special material that worked well, have to do some digging on aftermarket ones..

[Kickstart]

Hmmm... yeah, as I recall it's not he material but the way the teeth were cut, and I don't believe they're available anywhere.

Also, I'm not sure when they stopped supplying them.  You may not have the original OEM "cut" anyway.  Try reaching out to Hondaman to see if he can shed some light on how to check.  If it's not the original cut then just get an aftermarket one.  If it's original, then maybe consider re-using it if the teeth don't look worn.

All that said, what are you riding plans for this bike.  If you're planning on doing some touring on it, you may just want to buy all new stuff and get yourself an O-ring chain.  Sure, you'll lose a couple hp at the wheel, but the convenience of not having to clean/oil the chain every 500 miles (especially if you're on a long trip) I think makes up for it.   If you are racing it, or just need to squeeze out every extra hp (which I totally understand) then ignore my comment on the o-ring.

 

[tweakin]

Ed, I am using this sprocket on the K.  http://www.amazon.com/gp/product/B004ZIXIKW/ref=oh_details_o03_s00_i01?ie=UTF8&psc=1  The photos are not what I got, it actually looks pretty close to stock as you can see in the picture.  It is a Sunstar stock replacement steel sprocket.



For the front I used
http://www.amazon.com/gp/product/B004ZIVPZM/ref=oh_details_o04_s00_i02?ie=UTF8&psc=1

with an o-ring chain.

[edwardmorris]

Thanks Chris, building this as a mundane daily rider so not too keen on saving HP fractions, all in favor of low/less frequent maintenance I looked back at Mark's book, the original Honda material, much like their crank bearings, was softer to allow grit to embed in it instead of hurting other parts, along with what you mentioned about the cuts.

Tige, thanks,  just looked at Yamiya and its the same brand they're selling too. How's it been working out for you? I might just get the Sunstar set with a low maintenance chain.

[Terry in Australia]

Ed, not wanting to start an oil or tire thread type argument, but don't get too fussed about using OEM sprockets, good quality sprockets (JT for example) are at least as good, but probably better than OEM.

A note about O ring or X ring chain maintenance too, the rings seal grease around the pins and inner rollers to stop them from seizing/wearing, but you still need to use a good quality chain lube to stop the plates and rollers from rusting/wearing.

If you ride in wet or dusty conditions, you need to keep them cleaned and lubed just as often as you do non-o ring chains. Cheers, Terry.  

[edwardmorris]

Thanks Terry for the chain clarification. Not too dusty around here but incredibly humid during the summer living between two lakes so rusting would be something I'll need to worry about. If O-ring chain is slightly less maintenance than one without, it makes sense to go with that for me. Also, I'll stop over thinking the sprockets, JT is the other brand I see listed abundantly but when I saw Yamiya selling Sunstars, I figured that's more close to OEM...

Still too bloody cold out here to do any kind of painting, desperately waiting to paint the engine cases and frame so I can start putting this thing back together. But there is plenty of little stuff left to deal with until then anyway so hoping to get more things squared away on my day off tomorrow.

[edwardmorris]

Had some time to clean up a few more parts, is this cam toast?

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