fork removal-bridge fork top needed

jvandyke

Going in for fork seal/boot refresh.
Manual is a bit foggy (me too). After all the hardware is off, wheel, fender, caliper, top fork bolt cracked loose (unfortunately; literally, see below), upper pinch bolts out, lower ones removed....then what? That's it? They're supposed to pull out the bottom? Don't seem to want to move. Thought I'd ask before I get out the BFH.
BTW
bad news, triple tree clamp/bridge fork top/ the upper pinch bolt bracket is cracked, looks like someone ran this poor girl into something. I probably should source a new/good used one, eh?
Part number 8 if this loads.

Wonder if this one from a later bike will swap over.North City Vintage click me

tbpmusic · Posted: Fri Apr 22, 2011 10:48 am Post subject:

Yeah, you might have to whack 'em - they've been there for a LONG time.

Shouldn't be too hard to find a new part - all CB500 Fours and CB550 K0/K1 is the sane parts.
As you discovered, that top clamp can be fragile - there's a tightening sequence when you put it all back together, be sure to appraise yourself of it. It's a common topic on any Honda forum.

Probably in the manual somewhere - CB500 Shop Manual

butch8231 · Posted: Fri Apr 22, 2011 1:26 pm Post subject:

Got one $25.00 PM me.

jvandyke · Posted: Sun Apr 24, 2011 10:03 pm Post subject:

Hopefully I can snag the one Butch has. Seems there's supposed to be a washer in that pinch, there wasn't. I need to get the right ones or at least know the thickness. Shows one in the schematic so some PO screwed the pooch there eh?

MR.CHocko · Posted: Mon Apr 25, 2011 1:07 am Post subject:

They are the same parts up to '76 so easy to find one. Definitely don't ask me because that is one of the parts that I tend to hoard.

jvandyke · Posted: Mon Apr 25, 2011 5:32 am Post subject:

Which models? CB500/CB550 through '75 AND 750s?
This '76 750 looks different.EBAY

jvandyke · Posted: Mon May 02, 2011 11:04 am Post subject:

I shot the tube clamp zones with penetrating oil and let soak a few days, then used a wooden block to drift them out from the top. Tubes show areas of rust and scale in zone between clamps. I'll polish it out as best I can. Didn't get very far with tube tear down yet, waiting on parts so no rush.

tbpmusic · Posted: Mon May 02, 2011 12:10 pm Post subject:

jvandyke · Posted: Mon May 02, 2011 1:45 pm Post subject:

Yep, though Butch set me up with a good used one (upper fork brace), thankfully.
Can't get the spacers though so I'll make some that "seem" right and watch my torque.
I think manual says 6lbs or so. That's not much, no wonder so many over tighten and crack 'em.

jvandyke · Posted: Tue May 03, 2011 7:40 am Post subject:

Got the one from Butch.
Not exactly the same.
I did notice the risers are slightly different heights. The busted one is still on the bike and the new was wet with primer but it seems the new one's risers are about 1/2" shorter. I don't think this is a problem, in fact I always thought the cables where a bit stretched as it was and maybe the one that is on there and broken is wrong? Anyone have a clue on the differences? Hopefully that's the only difference.

jvandyke · Posted: Sat May 07, 2011 10:32 pm Post subject: brace mix of parts

Went to reassemble and discovered a major problem. What I think has happened was sometime in the past the front forks were replaced with a 750 triple tree. I think this simply because the riser on the top brace was taller on what I removed. Butch sold me a 500 top brace. Thinking the only difference was the handle bar riser I ignorantly proceeded. Now reinstalling the tubes I find the spread between them to be significantly different. Does this jibe with what you guys know?
So, I either need a lower brace from a 500 or another good top brace from a 750. Sound plausible? Any other way to ID what is on my bike?

butch8231 · Posted: Sun May 08, 2011 6:31 am Post subject:

Sorry for all the problems you are having. If you needed both the top and bottom I would have sent both. Let me make this right. Send me $15.00 to cover shipping and I will send you the matching lower brace for no charge. Sorry again for the trouble you are having. This should cure everything so you can get that project going. cheers

jvandyke · Posted: Sun May 08, 2011 7:23 am Post subject:

That'd be great Butch, thanks. I don't feel like you owe me anything though, it's not your fault some PO put front end bits from a different bike on there! Thanks for your help figuring it out, I'd still be scratching my head insisting my bike was 100% OEM.......apparently not!

tbpmusic · Posted: Sun May 08, 2011 7:25 am Post subject:

From the good folks over at HondaTwins.net - this is all accurate..........

Trees: TOP...
CB 450, CB 500T, CB 650/4, and early CB750/4 tops all exchange.....The 750,
650 and 450 (500T) share the identical spacing AND offset (a non-cushioned
750 top tree will fit to a 450 bottom tree (stem and bracket) for those who
desire rigid handlebar mountings.( the 750 stem is longer.and only fits the
750) The cushioned 450 top tree will fit the 650 lower tree and forks if you
desire the "give"....
The 500/4 and 550/4 trees have less offset, but will fit the 450 , 360, or
350 neck ( if someone wants 35mm forks on their 350/360 cafe bike.)

Trees: Bike to bike: 360 trees (350G) will fit any 350, any 360, any CM 400
Variant, and the 450/500T, 500-550/4 and 650/4 necks

450 trees fit 450's and 500T and can be used as a pair on the 500-550/4's or
ANY 350, 360, CM 400, or CB 650

jvandyke · Posted: Sun May 08, 2011 7:56 am Post subject:

Thanks for posting that.
So it seems I do probably have a 750 tree on there, or at least something other than a 500K since the top brace I got from Butch is from a 500 and doesn't fit. Bottom line, I should keep putting 500 parts back on since I at least know the top brace from Butch is from a 500, the bike is a 500 and eventually I'll get things to mate up again if I stick with the one good known bit; 500 top brace. Hopefully the lower one from Butch will be the final bit. I assume (pretty ignorant here) the bottom brace is integral with the stem so I'll need to take it all apart, head bearings and all, hopefully just repacking and using all that. Fork tubes and all appear to be 500 as far as I know.
I'd never have known all this but for the cracked top brace and the fact the cables seemed stretched a bit, due to the higher bar risers....I think. Not sure what to expect running cracked top brace (both sides) I assume that's pretty bad, although I never noticed any handling issues, I'd think the strength of the whole front end would be severly compromised and catastrophic failure is possible?
I put my kid on the back sometimes. Safetly first.