Topic: Asking for help: Any experts that can rebuild a CB450 master cylinder?

[fendersrule]

My girlfriend has been getting screwed on a craigslist recently. I've had 100% luck with craigslist via distant purchasing over 10 times.

She is 0 for 3.

Some guy failed to mention that his handlebars were slightly bent in two spots, and now she's out $50 on that. Still looking for bars.

Some guy sold her a tach for a CB450. While a nice tach, turns out it's for a CB500 four. She's out $30 on that.

Some guy also sent her a master cylinder that was completely gutted. $40 out on that.

I have no experience or special tools rebuilding master cylinders. Is there an expert here who has spare parts and a rebuild kit to get this thing working again? The guy removed all hardware off it, so having spare hardware is key. We already have a lever.

We considered David Silver Spares, but they charge a HEFTY amount for shipping on the nice repro that they have. She just wants to get what she has working again.

This is her first restoration, and it's sad that these things had to happen. I'm hoping that she gets excited again.

[totty]

Provided the bore is in good condition fitting a rebuild kit is easy. The kits come with everything required and the only special tools required are circlip pliers.

Check the bore for scoring or rust. For very light corrosion I've gotten away with using a bit of wet and dry rolled up (hone tools are available) for anything deep the fix is to bore out and sleeve - a replacement is likely to be cheaper.

I'm in the UK so can't advise on where to buy the kit, but make sure you get it from somewhere reputable - the last cheap kit I bought (CB400A) had an incorrectly sized washer and circlip, I reused the old ones but that isn't an option for you.

[Terry in Australia]

Your MC is probably the same as the one used on all of the SOHC4's Fenders, so you could rebuild it (no special tools required) just by buying an eBay MC rebuild kit.

Looking at your pics though, I'm not sure that the piston bore in your MC is all that good, so a replacement MC might be a better option, if you're not doing a 100% original restoration. Here's a couple on eBay that will work on your bike. Cheers, Terry.

http://www.ebay.com/itm/New-Front-Brake-Master-Cylinder-KH400-KZ400-KH500-CB750-KZ900-Z900-X03-/271270201864?pt=Motorcycles_Parts_Accessories&fits=Model%3ACB750&hash=item3f28f6ca08&vxp=mtr

These are good, I used one on my CX500, and half the price of the first one:

http://www.ebay.com/itm/Honda-CB-Brake-Master-Cylinder-CB650-CB650SC-CB750-CB750SC-NEW-/281043473694?pt=Motorcycles_Parts_Accessories&fits=Model%3ACB750&hash=item416f7f151e&vxp=mtr

[fendersrule]

Yeah. The mc we have is still missing hardware on the underside.

I like the first link. Maybe she just needs to fork it out and take her loss.

[tbpmusic]

That's almost the same one I used (mine has a sight glass) - easy to bleed, on the road in minutes, no leaks - cool......brake fluid is death on paint.......

[MoMo]

That's almost the same one I used (mine has a sight glass) - easy to bleed, on the road in minutes, no leaks - cool......brake fluid is death on paint.......





I used that or something way similar on my Silverwing and it worked very well.  I remember the cost was less than 40 shipped....Larry

[fendersrule]

Yea. Bill, you've only said good things about those master cylinders. I think we prefer to get the more "accurate" ones as seen in the first link, even though it's more money. The square one reminds me awfully a lot of the DOHC 750s which I don't like. Our bikes should have round things and not square things!

One thing I've learned is that I would NEVER buy a used master cylinder...unless I tested it...and got it dirt cheap. Going to eBay and buying a used M/C for $50 is taking a risk when you could buy a brand new one for $50-90 (depending if you want the square one or if you want the more accurate repro).

David Silver Spares and eBay are the only known sources of those round ones...I have yet to find it anywhere else. Beware as though it appears very cheap on David's site, his shipping is just as much as the unit itself, if not more!

[Stev-o]

You know DSS has a location in PA, right? Can't imagine shipping to be more than $15.

http://www.davidsilverspares.com/CB450K5-SUPER-SPORT-1972-USA/part_123889/

Does not pay to rebuild MC's anymore.

[70CB750]

Once you get the secure washer out of the MC, you are 80% done with the rebuild.  At least time wise.

[fendersrule]

Wow, $16 is much better than what the guy quoted me in the email. I want to say that it was more than twice as cheap.

I'm sure she'll be ordering that one Steve. Thanks a bunch!

(I wonder if the OEM cap will fit on this unit)....

[Stev-o]

Wow, $16 is much better than what the guy quoted me in the email. I want to say that it was more than twice as cheap.

I'm sure she'll be ordering that one Steve. Thanks a bunch!

(I wonder if the OEM cap will fit on this unit)....

Yes, should fit.

Tip #2 - Don't  buy used handlebars.  8/10 they will be bent or wrong.

Tip #3 - Know what you're buying. Don't trust the seller that a certain part is for your bike.

Why are you letting her make these rookie mistakes?

[fendersrule]

Then maybe I shouldn't have bought those killer K1 bars from Tews.

It may be best to just find a company that can make them. Though I bet it will be $200.

[Stev-o]

Then maybe I shouldn't have bought those killer K1 bars from Tews.

I believe your first post stated issues from buying parts off a listing on CL, not forum members.

[fendersrule]

I think I may have found her some bars:

http://www.cb750supply.com/products/2/chassis-brakes/63/handlebars

The K2 bars are pretty damned close to Cb450 bars I believe. I think they are only an inch shorter, which would look pretty ideal on a CB450.

Thoughts? Same width. Very similar pullback. Already drilled out, new, and $38. She thinks it's too good to be true...

I wouldn't think any cabling would be an issue loosing only an inch.

[MoMo]

Fenders,  450 and 750 handlebars are quite similar.  will do for anything other than a concours resto...Larry

[fendersrule]

If any of you have a CB450 or CB450 bars, can you measure them and see how close they are to the K2 bars?

I trust my measurements, but bars can be difficult to measure so it pays to get more data. I want to make sure that they are pretty darn close.

Thanks!

[Danno]

the master cylinder is the same one the cb 500, 550, 400, 350 fours all use any good one will work and the master off a many kz  's of the same vintage and rough size will work also looks nearly identical and was made by honda the only difference is flutes on the cap