1972 Honda CB175 Super Sport restoration

[KS]

[911hillclimber]

Leave me alone!
Have just tolerated 5 crashes of Modrilla outlook trying to get 26 photographs to a magazine...
Mind you, my brazing looks as lumpy as those two....
Day off all garage time tomorrow, bike arrives next Monday.

[jehintheuk]

My first proper bike was a 2nd hand M-reg CB175 that I bought in about 1979. Other bikes came and went, but I hung on to the little 175 at the back of my Dad's garage, before eventually selling in about 1995 back to the guy I'd originally bought it from!

Bike is pictured here in about 1998 at an earlier house. Many happy memories - and great bikes.

[911hillclimber]

I have not yet met anyone who has not had anything but warm feelings for these lightweight twins, first bikes, first bike with the girlfriend now wife and more.
They are true darlings to work on, beautifully engineered, can't wait until Monday!

Theproject can then get underway in earnest and I can see what is needed.

Worst bit is finding the unique 175 side panels. Seems almost all Hondas lost their side panels over the years, hyper rare if you want originals, hyper expensive if you buy replicas!

I have 6 shallow dents in my new tank which will be a tease to get out.

[911hillclimber]

Just sold the Terrot MT1 French follie, Peugeot BIMA next.

Things sell on ebay if it is an auction and not Buy it Now.

Looking for a complete clear-out and focus on the Honda.

[911hillclimber]

Quite a day and a fresh new start.

The Terrot was collected today. It is going up north then off to live in rural Southern France to get the baggett's every morning.

The Honda arrived an hour later to pick my spirits up. It's a cracker, lots of + and lots of - but just what I wanted/needed.

After an hour or so looking closely, it will need a total nut and bolt strip and restoration, just as my first one did.
So, soon a big strip apart, not going to try to start it, just assume it needs everything.

Wanted list is quite large and some parts are rare to find, my first one was well nackered but totally complete.

Time will tell, and you can read all about it here.



The target!

[Hugo 356]

Mentioned this thread to my Dad at the weekend. He had a 1968 CD175 in his youth which was a reliable successor to his Ariel Arrow. Looking forward to following progress...

[911hillclimber]

As ever, there are surprises with any project, and old motorbike are no exception.
This is a cb175 Super Sport, twin carbs, high lift cam, red line at 9500, so Honda.
However, there was a cruising model, the cd, one carb, softer cam etc and about 3 bhp less.
The cd bike did not have a tachometer, the cv did. It was driven off the came using a cable, but this cv engine does not have such a drive, and looks to have a cd cam.
However, the head has the twin carbs, not the single.
Further, the engine looks like it's never been apart in its 26k miles, so why does this matching numbers bike have a cd cam and no tacho drive but has a tachometer?

Anyway, I'll convert the cb engine to correct spec, 3 bhp is 15% more after all.

So far missing parts are up to 26 items so far...

Hope your father will find this project interesting!

[jehintheuk]

Did the CB have a different cam profile? I wasn't so sure. I always put the extra 3bhp down to the twin carbs. If I recall, it was quite easy to break the tacho drive on the end of the camshaft. The drive was quite brittle alloy and if you overtightened the bolts when you refitted the drive you could break the housing. Therefore, it was not unusual to see that someone had fitted a CD end plate to support the end of the cam and the tacho just didn't work. Probably complete rubbish but that is what my memory tells me. Replacing the housing doesn't need you to replace the engine, so no reason why the numbers wouldn't still match. It was beautifully engineered engine, but quite easy to damage things during rebuild if you didn't use a torque wrench. Ditto my next bike after the CB, which was a series 1 400 Four.

[911hillclimber]

I read yesterday that the cams forms were different but before I thought they were the same....

The cd cam does not have the machined slot to take the tacho drive gear, so I've bitten the bullet on a tacho drive end plate and gears and a cb slotted cam to change any cd over to cb spec.

[911hillclimber]

The strip-down has started, bit slow as the garage is very hot.

The previous owner was 'restoring' this poor bike, and had a unique way to restoration, namely a big box of M6 cap head screws, a bigger box of unknown old bolts, a Very Big tin of thick black paint that cellulose thinners will not touch and left every fastener re-assembled with hand tight torque on everything.

The seat is evil, and has been stripped of the original Honda parts. It is an alloy base, layers of upholstery foam and a gallon of Evostic. Going to the skip tomorrow.
The instrument bracket is an odd thing, chunk of steel bolted on and black paint.

Lots of rubbish, but some goodness too.
The loom is new Carbs look ok found the hard to get clutch adjuster the wheels are perfect, frame looks straight, parts for the engine on their way. My gamble on the rear mudguard paid off!

Tomorrow is planned to get the engine out, wheels and forks off and to get a pile ready for grit blasting.
My mind is bouncing o all directions, but I want to try to do as much as I can at home. The engine will be the first to get done, they take some time, a lot of details as you go, bit like a 911 engine but much smaller.











post pictures

[911hillclimber]

Day to myself in the low-bake oven of a garage, but the plan was to get the engine out and totally apart and to get the scrap down to the tip!

The engine is a TIGHT fit in the frame. Getting it back in all painted will be a heart stopper, it was last time.
New silencers came off easy, all fasteners hand tight again.
Stripped the carbs off and anything else delicate, undid all the bolts (8) holding the engine in and put the bike on it's side so no heavy lifting. Got it out with a screwdriver pry in the right place and then found my old engine stand brackets to get the unit on the stand, so much better than working on the bench.

I save margarine tubs and use them for sets of parts as they come off, works well and slowly it all came apart. Only one screw was a sod.

Head, cam etc all eased out and in great condition, the head off to reveal brand new pistons installed (I'm NEVER this lucky, everyone else is).
Clutch out after the pesky centrifugal oil filter bowl is removed (what a game), the welding wire trick described in the Haynes book was spot-on.
Clutch discs are all good and to factory spec, no wear (£80 saved). Kick start shaft is in fact in one piece which was a surprise.

Generator core extracted off with my special Lambretta tool saved from last time, starter motor off, why was this happening so very easily? Must be a disaster waiting...

No! and the lot is all stripped, the roller crank is smoooooth, and the inside of the crank case is really clean, never been apart since built in Japan in 1972.

Took the old nasty seat and other junk to the tip, and came home with an ECO Ranger acoustic guitar! It was about to go into the Wood hopper, just got there in time. A project waiting for another winter day.

Frame next, all wheels brakes etc off, forks stripped (murder) and order some more parts. Best bits are in the USA ($$$$$$$).

Hope to grit blast the cases next week and other frame parts and clean, clean, clean and spray silver smooth Hammerite.

[Kneeslider]

That's all looking really nice! My first bike was a Honda CB100N which I learned and passed my test on. Bought for £325 and then sold about 4 years later to a mate for £300. My only gripe with small Japanese bikes is that the frame welding is serviceable, but never very nice looking, and they have an odd habit of welding lots of fairly crudely made brackets to everything which to my mind look fussy compared to European offerings.

My Velocette is progressing, but not very rapidly. The hubs are all cleaned up, new bearings and laced to new alloy rims. Right now I have enlisted a friend with an Oxy set to unsweat the brazed on frame lugs that need moving, but we have found out that the lugs will need a little more work than just moving backwards, and I need some bravery pills before I make alterations to a lug on the OHC cambox to clear the frame top tube.

[911hillclimber]

Agree on the Jap welding, obviously few/no robots in the 70's!
This cb is no stranger to factory bits welded on, but the welds are carefully hidden.

Please to read someone is watching this!

Strip-down of course is the easy bit, discovering new pistons and such like is nice too esp when the bike came with 2 Honda pistons +25 thou, I thought the last owner had bought the pistons but had not fitted them.
My first gold cb was easy in comparison as it was complete and original and very rusty.
This blue one is another case altogether.

Complete originality is King, but such projects are very rare now, they have all been done or stashed away.

[Kneeslider]

[quotePlease to read someone is watching this!

quote]

Of course! A diet of nothing but Porsche would be ultimately dull!

My next bike after the CB100N was a 1977 XS250 which coincided with a period of personal poverty. I really wanted another Honda, but there were none about for the sort of money I had. It managed to seize the left hand cylinder after a merciless thrash and had to be rebored and rebuilt, only for it to fail again in the same way after only about 1000 miles. I think the cause of the second failure was detonation that ultimately destroyed the top ring. To this day I wonder if the pattern (cheap) pistons I used pushed the compression just a little too far, or maybe the squish wasn't quite right. But then, I was young and foolish (now older and still, but differently foolish) It might pay to crush some solder on the piston tops and see what clearances you have, and calculate the CRs