CB360 from rat cafe to real bike!

[MiniatureNinja]

1 year Update:

It was invited to the 1 Moto Show in Portland Oregon - a once a year show with top builders and I feel super humbled to have been invited along side the likes of Madhouse, Boxer Metal, CROIG, and others I've looked up to. It was a hell of a trip there - I'm 12 hours away... it snowed. We put the bike in the truck and hauled it there and back (it snowed heavily on us both ways)

Bike was also featured on Bike Bound Blog after one of their editors noticed it at the 1 Moto. Lots of instagram fans followed... i try to keep it updated with pics of the bike and stuff I am working on

According to my Google Maps Timeline i've ridden the bike 1432 miles since "finished" in last July. It's broken down twice, both my fault (battery cable fell off once, and fuel petcock clogged up once)
Recently I made the final switch to Alloy rims. It was a chore - more than I bargained for.. arms were sore getting tires on and off by hand and truing spokes. It's really NOT that much of a weight savings and to be honest I wouldn't do it on another bike.

It's loud - smelly - uncomfortable. The licence plate won't stay put and is mostly crushed by the shock reservoir. I don't always ride it with the 'stacks - only if I've going to a show or something. The sun has faded away the "cheaper" clip on bar's black finish to a dull purple/brown. (typical of cheaper black powders/anno) But the paint is still great and the raw polished aluminium is easy to maintain. I haven't updated/finished the exhaust.. it's too loud - WAY too loud. I like it that way for now. Bike turns heads everywhere I go. It's been on display in a local Brewery for a month which was OK because it was really too cold to ride in April anyway here in the Foothills.

Been attending local bike meets twice a month with it, made a lot of friends - lots of fun to talk shop and old bikes... as it were... most of the "old guys" (I'm 38) had one of these CB360s at some time... I get lots of stores of trips up/down the coast with their high school sweeties... They love that I've kept it a CB360

 

[Jimbonaut]

Great new chapter, may the good times keep on keepin' on!

 

[MiniatureNinja]

Further Update.

im the spirit of continued improvement - and an abundance of parts. i've decided to upgrade the spindly noodle 33mm forks of the CB360 to BEEFY HULK HOGAN 35mm forks.

the process started with my other project, that had bent forks - I decided if I have to go with new forks, may as well get 35mm forks. So I got an entire setup to do that, then realized how stupid it was for the bike I am building to put the 35mm forks on the cb350 bobber, when I can just put them on my CB360 CAFE RACER and use the cb360 forks on the cb350. (playing musical forks)

"stock" (smoothed) triple on the cb360

I got a SL350 triple setup.. it's 35mm and the right offset/length for the cb360/350 bikes. Only problem, it's top clam is UGLY.

CB550 Top clamp that came with the forks I got:

I want something like a smooth billet top clamp with nicer clamping location but don't want to spend the money

so I got to work chopping the SL clamp up

and now I am left with a cleaner top and 4 bolt lower.

but again, I hate the outer clamp bolts. they just stick out too far.. especially on a flat top - as opposed to a drop triple
So I cut and welded up the gaps and holes

smoothed it

Before media blasting and equalizing the finish - will then be polished

 

[Sderbyshire]

Nice work, i put a cb550 front end on my cb390 complete with dual disks...... really liked it !

 

[pidjones]

Looks nice. I've never seen that done. I know that the upper tripple does little support for the tubes, but how do you prevent twisting?

 

[MiniatureNinja]

I plan to run dual discs but I will be using the CB360 front hub (modified). I don't want a 40 spoke wheel or 19's on this bike
The top clamp is press fit (cannot twist it by hand) that said.. I will most likely tap a hole, use an insert and run an 8mm set screw into the fork. That depends on what fork uppers I can fun, as the ones I have are good - just have corrosion in the usual spot where the headlight ears held water for 50 years

 

[Sderbyshire]

Inkept the 360 wheel, needed some spacers to centralise but worked ok

 

[Sderbyshire]

Here’s a shot that might help, shows that i had to offset the wheel/caliper mounts

 

[MiniatureNinja]

Yea I know i'll have to offset the right side caliper as that's how the originals are. Thanks for the shot! that will help. Did you have to skim the left side of the 360 hub? Looking at it, that seams like that's what i am going to have to do. I don't need the speedo as I am not using it, so if I lose the cap for it, no biggy

oh! I also smoothed up the lower clamp. this will be powdercoated black

BEFORE:

AFTER:

 

[crazypj]

I thought you did 390 plus cam and everything?
That was a CB500F or maybe an early (1975? CB550) top clamp.The fork legs were only chromed on the part that needed to contact seals so tops always went rusty. Lter CB550 fork tubes from F1 or F2 are chromed over full length, can't remember if the FourK was same?

 

[MiniatureNinja]

378 with mega cycles cam and larger intake valves, porting, ect.
I can find NOS fork tubes for like $200 each but I don't think I want to go that nuts

 

[Sderbyshire]

Yea I know i'll have to offset the right side caliper as that's how the originals are. Thanks for the shot! that will help. Did you have to skim the left side of the 360 hub? Looking at it, that seams like that's what i am going to have to do. I don't need the speedo as I am not using it, so if I lose the cap for it, no biggy

no, i didnt need to skim the 360 hub
iirc it only just went in with the speedo drive, and ended up 1mm offset but handled ok

 

[kickracingmotorcycles]

Very good work. I think your seat length is about 8 inches to short, but that's just my opinion.

 

[MiniatureNinja]

I'm not tall (hence the name) and no one will ever ride on this bike with me. The seat was suited for my riding style and position - I don't use rearsets, and I don't need to move back and forth on the seat. so it's actually perfect

 

[ex119x]

I plan to run dual discs but I will be using the CB360 front hub (modified). I don't want a 40 spoke wheel or 19's on this bike
The top clamp is press fit (cannot twist it by hand) that said.. I will most likely tap a hole, use an insert and run an 8mm set screw into the fork. That depends on what fork uppers I can fun, as the ones I have are good - just have corrosion in the usual spot where the headlight ears held water for 50 years

I have doubts that your top triple, even with a set screw will be able to resist the twisting forces on it. It appears that you have the skills and tools to do a better job of it. I am afraid that an 8mm set screw will concentrate the twisting forces into a single point in a not overly strong cast aluminum piece. The triple clamps rely on uniform circumferential clamping forces to resist movement based on the clamping piece's surface area. Forks which don't use a clamp use a tapered fit and the top fork bolt pulls the tapers together. The forks on my 73 Sportster work this way as do my external spring CB350 forks. The 2 solutions that come readily to mind (and I am sure there are others which are probably better) would be to slit the upper between where the tube goes and the hole where the handlebar risers went and put a pinch bolt there. It wouldn't stick out and would provide the clamping forces you need. You would probably have to weld some material underneath the clamp to provide enough meat to drill and tap. The other solution would be to bore out the top triple to accept some tapered split collars which could be pulled up into the top triple by the fork bolts to provide the clamping force you need. That would require some lathe and mill work which is well beyond my capabilities. This might all be overkill and what you are doing might work fine, it just wouldn't give me the peace of mind I need in the front end of a bike. Especially since you are going to even more braking force with double discs, I would be afraid of what the forks would be doing under heavy braking, especially in a turn.Putting a fork brace or front fender on would help even more to resist twisting.

 

[MiniatureNinja]

That is what I plan to do now

edit: I do run a fender brace

 

[ex119x]

That is what I plan to do now

edit: I do run a fender brace

Cool. I can't wait to see what solution you come up with.

 

[crazypj]

For some reason I didn't think to look at page 1 earlier (doh).
The pictures were not loading either but today they did (weird?)
Now you have top yoke welded up, a longish bolt diagonal between the handlebar damper holes and the outer fork hole would give all the clamping you need.
You just have to make a slot between the two sets of holes.
Drilled from the rear and counter bored you can have front smoothed out.
May be a good idea to reduce depth of the damper hole mounts underneath as well?

 

[MiniatureNinja]

Nice work, i put a cb550 front end on my cb390 complete with dual disks...... really liked it !

I suppose you use the cb550 triple?
turns out I can't use the xl350 triple I wanted to use.. it's WAY too narrow. I've put a ton of work into these things tho. so now I will have to find a triple that will work and do the same thing.

 

[Sderbyshire]

Shame, yes i used the 550 triple.
i did tidy it up as it was ugly!
good luck!