Topic: cb500 in Aussie land.

[big bad bob dog]

Hey all,
Thought i'd throw my project up as it's coming along. Been a long time lurker, and the wealth of knowledge on these honda's here have been very much to my benefit over the last few months.

Long story short so far...

Ebay. 500 bucks. This and a spare engine (550)...



Going to turn this into a cafe racer, and in turn it'll also be my daily rider.

Few goodies I have in store for it...

sr400 tank...



dunstall 4 into 2



and a pair of borrani rims. (wm3 x 18 rear) (2 1/4 x 19 front).



The 500 engine has fins broken off all over the place, not to mention the case itself is broken (points end). So I'm gutting the worn 550 cases, and replacing all the internals (besides barrels and head) with the 500 components.

Where i'm am at the moment:

Frame is stripped, and waiting for my friends truck chop shop tig welding skills. (im on the learning curve)



and the 550 engine is apart. Im measuring everything up to see what I can use (I'll be keeping the 550 clutch).



I've also been reading up on Hondamans advice on the 550 donk. So i will be doing substantial head work and blueprinting.



Lots to do!

[Mayor08]

Sounds like an adventurous build look forward to reading your posts as progress is made.

[scunny]

that sr tank looks good on the bike

[big bad bob dog]

cheers guys. Just messing with the frame. Pictures to come, then onto the dry build!

[big bad bob dog]

Just had my friends brother help me immensely. He bent, raised and welded on my rear hoop for the frame. I can't touch Laurie's skills, so if your ever in Gosford NSW, look up the chop shop!

[big bad bob dog]

thank god for tax returns. I'm now at that wonderful stage of buying everything I need. Question lads. Cb750 top trees. Can they swap with the 500/4's? I have to replace my chopped up #$%*ty one, and was looking at the bare cnc'd ones from cycle x.

[big bad bob dog]

Lads, your words of wisdom would be much appreciated. Alright. my good old friend came by and threw a swing arm on my table. His dad thought it would be a good idea to make a swing arm for a cb750 out of high quality mild steel in the 70's. He never ended up using it as he stumbled on a dresda 'arm. Apparently is has been test fitted on a cb750. It still needs a tab welded on for the rear brake backing plate rod to attach to.



Now i'm not sure about the exacts, but i was led to believe that swapping a 750 'arm onto a 500 frame is a direct swap with a +1 length. I also understand this is a custom made one, and that i'll have to ask my friends father if somethings up... cause....



Theres space between the frame and the swing arm where it connects. I'll have to make new spacers here obviously, but the actual swing arm rod is too small in OD to fit the ID of the swing arm. Can I machine a new rod to go through? (or find a cb750 one) or will I mess everything in some physics voodoo? I'd have to machine up some swing arm bearings as well.

Next problem...



The bloody space for the wheel is too narrow. Now, I could fix this by making up a new spacer to replace the old one that goes with the standard wheel, but i'm now worried about wheel alignment. If I make a new one that is narrower, would i mess things up? Would really like to use this.

Cheers lads

[Retro Rocket]

Gday Bob, i like the look of that swing arm mate, if it was made for a 750 maybe the 750 spacers will fit it? I am not too sure but i remember in the early 80"s putting a 500 wheel in my 750 while i had my tyres changed on my 750 wheel, can't remember if i used the 500 spacers or not but it's worth a look....

Mick

[big bad bob dog]

cheers Mick,

i'll enquire I look into that. If anything from that experience pops into your memory please let us know!

thanks

Bob dog

[Retro Rocket]

cheers Mick,

i'll enquire I look into that. If anything from that experience pops into your memory please let us know!

thanks

Bob dog

I'll try mate but i'm up too 19 of these bikes now and the one in question was number one........A lot of brain cell damage between then and now....

Mick

[Terry in Australia]

If you don't use that swingarm I'll buy it mate, I don't know what I'll use it in, but it looks nice. Cheers, Terry.

[Retro Rocket]

If you don't use that swingarm I'll buy it mate, I don't know what I'll use it in, but it looks nice. Cheers, Terry.

Eh Terry, i have this really nice bridge for sale mate......

Mick

[Terry in Australia]

If you don't use that swingarm I'll buy it mate, I don't know what I'll use it in, but it looks nice. Cheers, Terry.

Eh Terry, i have this really nice bridge for sale mate......

Mick

Serious Mick? Geez, I always wanted a bridge, how much mate? 

[Retro Rocket]

You on a buying spree...?    I thought you were trying to thin the herd, or are you just making room for some more....    Kinda like musical chairs.....

Mick

[Terry in Australia]

Nah, still thinning mate, and I'll be happy when the 4 bikes I sold last week all leave my garage, I've got their money, but I need the room before I can do much more in my garage, bloody interstate buyers! 

[big bad bob dog]

I really want this bloody swing arm to work. I'll be making new bronze bushings for the swing arm, so it should fit the pivot pin. The remaining problem at the other end with the wheel spacing, i'm still pondering. Its 10mil too narrow. Making a new right hand spacer is not a problem, its the hub side that'll be difficult. A bit of measuring to do. Hrmmm.

Got some goodies today...





I love Fast from the past.

Thrown on the rear sets...







Forgot the spline so i'll throw in the other engine to size everything up.




Picked up an EX500 caliper. One issue. Seeing as it has two pistons and the smaller one is meant to be behind the leading piston for wear reasons, i think this is for a right hand mounted disk. I'll use it none the less, just need to knock up a mounting plate.




... also picked up the steering damper. This will probably be the last thing i put on the dry build, so I can see if any cables are in the way blah blah blah.



and finally the fork brace...

[big bad bob dog]

what the hell is wrong with photo bucket! arg. Wont let me rotate anything.

[Retro Rocket]

Got some nice bits there Bob. Don't worry about the pics mate, we are all a bit twisted here anyway so they look fine....

Mick.

[big bad bob dog]

Hey guys,
Been taking my sweet ass time, but as we are all aware, moolah dictates speed. In this case it's the speed of the build.

Shipped that ill-fitting dunstall exhaust that ACTUALLY needed the pipes cut in order to fit (ill) correctly, to a pal stateside. Pretty sure mlinder told me how awesome MARVING pipes are. He's right.







Now perhaps i'm incorrectly recollecting this, but a little birdy told me these pipes are a replica yoshi job. Replica something for sure. If anyone has history, or runs these pipes could you let me know how they go?

I'm also on the cusp of some finacial influx, so hopefully the dry build will be sorted soon. Have to make a seat, weld in battery box, mount alloy fenders, adapt new caliper to disk, shave and drill disk so as to fit caliper, mount oil cooler, weld in steering stop so i don't ding my tank, mount steering damper, oh and sort this swing arm.

Once THATS done, obviously rip it all apart  paint it and smack it all together with new bearings ect. and THEN build the engine.

Horray.

[Retro Rocket]

Looking good Bob, like the pipe....What you doing for a rear section, tailpiece.?

Mick

[big bad bob dog]

sure will be. Goin to do it right, shape foam, make mold out of glass, touch it up, reverse mold then bang. Seat. Don't want the battery in the bum, trying to centralize as much weight as possible for obvious reasons. Going to use one of those tiny glass matt 12v battery. Going to be kick only, so not a big deal, and it'll fit beneath the seat and battery box i'll weld in.

[Retro Rocket]

Nice, good to see you have kicked up the rear frame rails as well, seen plenty that don't....

Mick

[big bad bob dog]

oh i know. Theres a guy down here who think's he built a show winning 450 twin, after he slapped a bunch of BCR part on it. After welding the rear loop on, he had about 1-1 2/3 of in inch of travel till it bottomed out. Scary #$%*, if you went around a corner on #$%*ty 40 year old suspension, hard.

I'm on the cusp of some proper funds so thing will get done soon i hope. Need to make a front fender that'll fit under the fork brace as well. Hrmmm, have to play with glass this week as well.

[big bad bob dog]

Trimming the foam for a mold of the seat. Never worked with glass before. Should be interesting...

[big bad bob dog]

First glass mold...