Abarth’s 1972 Honda CB350k Cafe Racer

[Abarth]

Thanks mate, I’ll get in contact

Frame is back from the welders, stoked with how it’s turned out. 

Fitted the rear wheel and took some measurements, fitment clears the frame even with the big tyre.

Added in a bracket to mount the seat latch mechanism too, also doubles as frame strength.

Continued on with the engine build today, got the piston and rings in, everything was going great until we noticed small cracks on the camshaft where the timing chain cog fits on. Turned out to be cracked right through on both sides. Yip that’s game over for that cam.

 

[Abarth]

Engine build has been a bit more of a mission than expected.

Found a replacement for the cam, new second hand one is mint compared to the old one. Can see the old cam on the bottom with chunks missing from the lobe and grooves ground into the surfaces. Also found some good replacement rockers as those surfaces were equally as worn. Pretty much all the internals are either new or as new in the engine, pistons, gudgeon pins, rings, cam chain, tensioner, cam, rockers, etc... hopefully this thing isn’t rattley when it fires up.

[Abarth]

 

Painted the frame and got the motor back in the frame today. Lots of figuring out where all the bolts went as most of them were sitting in a bucket before buying.

 

Front guard turned out perfect, so many hours spent to keep the rolled steel edge on the front. Stoked with how it turned out.

On its feet for the first time!

Placed all the pieces to see how it looks all together..

Big shout out to Eliav for doing the upholstery, leather with the dark blue stitching looks mint!

 

[Abarth]

Had a play with the headlight. Managed to order the wrong size so it’s huge haha but was keen to see how it looked with a yellow tint.

Once the smaller one arrives I think we’ll keep the yellow as it pops against the blue.

Next is the wiring, so much to do before the Distinguished Gentlemen's ride in Sept!!

Edit: man that rear tyre looks huge, thinking of down sizing as it looks a big out of proportion in the profile shot.

  

[Abarth]

Been putting the front together.

Added in heated elements inside the clip on tubes for those cold days.

Indicators are now bar end indicators, they have a white LED and orange LED in them so we’ll hook the white to the headlights and the orange to the indicator relay.

Connected all the cables up, we used short versions which were perfect with the clip ons.

Found that the headlight bracket we fitted made the headlight stick out too much. On the hunt for brackets with shorter arms. May even use the factory ones as they are short. Ordering some gaiters to fit over the fork too.

Anyways this is as it stands at the end of the evening. 

[Abarth]

Carried on with the wiring, cleaning up all the old connections and added in modern plugs.

Added in a regulator/rectifier to replace the old Honda ones.

Drilled holes in the underside of the clip on bars to feed the wires out and down into the headlight. Trying to keep the wiring tidy with some going through the centre of the frame.

Had my other Honda round to compare factory spec to cafe spec.

 

[Abarth]

Carried on setting the motor up today. Kept the points instead of a CDI as there is something oldschool mechanical that I like about them.

Tensioned the timing chain at 90 degrees after tdc. Then set up the points timing and tested the coils, got good spark so she’s getting very close to starting now!

Fitted the headers and noticed there isn’t much room between them and the rearsets. Might have to make some out of 35mm ID pipe to get the clearances. 

[Abarth]

Finally kicked this thing into life this arvo. Started easy as and sat there idleing like a champ.

Stoked the motor is working as it should have. One step closer to the DGR ride!

Still have so much to go, mainly wiring as the indicators don’t blink, starter motor is dead, rear set linkages etc.....

[xsinclairx]

Indicators not flashing will just be the bulbs/l.e.d not drawing enough current from the relay. Swap it out with another one. 

Its a nice build man, tidy!

[flyingbrick]

I think i have a new fav os bike build!!!!!!!

Supercheap and AE both sell solid state flasher relays which work with LED indicators. They are good even without led lamps because they make the slow flashing at idle problem lots better.

I do think your headlight is too high and vote flipping those brackets (I'm also not a good judge of style. )

[Abarth]

Thanks guys! It’s been a lot of work to get it to this stage.

I’ve added an LED flasher unit so I think it’s something to do with the wiring not being quite right. I’ll revisit the wiring once the controls arrive from AE and try to knock it out all in one go. 

Super Trapp reps should also be arriving too this week as there is an issue with the exhaust and rearset brake hitting. Probably going to make new headers to get the clearances.

Anyways she’s come a long way since the Trademe purchase that’s for sure!

[Abarth]

Big update mostly about clearances.

Firstly the Supertrapp reps turned up and wow are they mint! Did a test fit and fired it up which sounded great, stoked!!!

Now clearances, looking at a lot of other CB350 builds I always wondered why they added aftermarket headers. With the rearsets I realise that the factory exhaust sits too high so the brake leaver hits the muffler. Also the kick start hits the rearsets too, bit of a cluster really.

Gave it a quick tune with the glass plugs, found the 70 idle jet ran too rich so swapped it out for a 68 which helped when tuning with the Air/Fuel mixture screw.

Also added in the blue titanium hose clamps round the carbs, kind dig it kinda don’t, they are quite wide so they don’t quite fit. Can see them in this pic.

The push button controls turned up for the handle bars too; again quality and feel is immaculate so far, they also did a perfect job of setting up the buttons as some were momentary and others were push on/off.

Test fitted them to check and happy with the fit/clearance. I’ll thread the wiring properly down through the handle bars eventually.

Realistically this bike won’t be ready for the DGR ride on Sunday so the CB250k is hitting the ride again this year with the DGR headlight stickers to support men’s mental health.

 

Lastly found the winged Honda badges I brought ages ago to stick on the CB350. Factory colour is to fill them in white but I reckon black could be the go. 

Thanks for looking! 

 

[Abarth]

Carried on shaping and sticking on the badges, originally for the early CBs with the square shape tank but I liked them so much I picked up a replica metal set and stuck them on. 

Was going to paint the badges but like the raw alloy look so gave them a coat of Matt clear to keep them crisp.

Drilled holes in the clip ons and feed the wires through for the controls, now on to the major wiring to make sure everything works like it should.

Fitted up the gear linkage I got from AliExpress, so mint! A tad short which was completely my fault as a don’t know how I got the measurement wrong but hey it works!

Next is to build an exhaust which doesn’t hit the rearsets!!

[Abarth]

Long time and well over due for an update!

Got stuck in to figuring this exhaust system out, one which won’t foul rearsets and kick starts.

Came up with the solution to wrap the headers under the frame then back out by the lower swing arm. 
 

Did some other electrical stuff too, but here’s the pics of its current guise.

 

 

[Abarth]

Originally was going to do twin supertraps each side but having them hugging the frame at the angle I wanted just wasn’t working for the chain side. 
 

So scratched that idea and went 2 into 1. Used 38mm mild steel donuts and U bends to shape the exhaust. Mig welded it all together, gave them a couple coats of header paint then wrapped them in titanium header wrap.

[Abarth]

Been working on the wiring. Everything is working as it should except the indicator unit. Hondas actually use a 3 pin relay and I’m trying to use a 2 pin one, no idea why a 2 pin wouldn’t work but I’ll pick a 3 pin up to try tonight. 
 

Those AliExpress handle bar buttons are legit, really nice buttons with a mix of momentary and latch style buttons. 

The motogadget mini sensor still needs to be wired in but the display lit up all nice.

Hooked up the starter motor solenoid which spun up when I hit the starter motor but didn’t crank the motor over. Need to check the engagement rollers on the crank as I suspect they aren’t there. 
 

Getting close now!! 

[Kimjon]

I have that same led stop/indicating light strip and was wondering if it's okay for wofs in nz? I haven't fitted it yet because I have doubts...but keen to hear if it's okay?

[Abarth]

Same, hopefully the WoF guy is kind on the day. It already has a VIN plate so it doesn’t need to go through full compliance testing. They are intensely bright but yeah slightly nervous about it.

In good news I picked up a 3 pin flasher relay on the way home from work and it works perfect. Stoked!

Note: Rear wheel is crooked, haven’t put it together properly yet

 

[mutiny]

Have you had a look at the light strip outside in natural bright light? I have one on my bike and it's pretty dull.  I always take it off and use the factory light for a wof 

[Abarth]

Yeah it’s good in the daylight, I wanted to see what the motogadget looked like in the sun and it was mint too. I’ll get a pic and post it tomorrow in the sun.

Had it running again after all the wiring was done. Sounds ok currently, definitely want to pack out the muffler with more baffle to get the deeper tone.

Also need to sort out this headlight bracket, it’s too big for the bike so I’m after a shorter one to pull the headlight back into the frame more. And lower the front a bit.