Honda C90

[LathejackParticipant @lathejack]

I visited the Newark Autojumble yesterday, and finaly got through the gate after sitting in a jam for one and a half hours to move just over half a mile.

I was in a frenzied rush to check all the stalls for parts for my two recently bought BSA motorcycles, but I did spot a C90 on offer in the distance, but I just didn't have the time to take a closer look and get any details. I am sure it was the 90cc model judging by its later type styling.

I had the C70 version in 1982, with a bit of care and simple maintenance they are a rock solid and unburstable engine, as is the C50 & C90. I wish my BSA engines were as unbreakable and durable.

[john fletcher 1Participant @johnfletcher1]

Twenty or more years ago we were holidaying in the Pyrenees and met up with a young couple who were camping, on the way to Spain. Two up with basic tent etc on a Honda 90, they already passed through France. I asked had they had any problems, no they replied, it just keeps going. If you want to see a moped loaded go to India, mum ,dad two kids and chickens in a box on the carrier, some times a pig, amazing. Then see the road side mechanics and his "workshop" who is keeping them all going. Petrol sloshing around, stick welder crackling away, often no face mask either, no one appears to be get injured, and pollution level is terrible. John

[pgk pgkParticipant @pgkpgk17461]

Even i had a C50, until…

One w/e riding it home to my folks on an icy day I saw a police motorcyclist come off his bike at an icy roundabout. I was laughing myself silly over that until karma collapsed one suspension arm on the next roundabout and icy gravel ripped my trousers and underwear off. It was a cold, slow 30 miles in a t-shirt with my top wrapped around the more important parts and dragging my feet to control the suspension wobble..

I upgraded my transport to a £27 10s A30 after that…

[Cyril BonnettParticipant @cyrilbonnett24790]

We went to the bol d'or in 1983 on a Yamaha XS850, left Calais along with a load of other bikes, one a Honda 90 loaded with a rather large rider and a tent plus bags and a crate of beer, he arrived about three hours behind us. The same bike was used for 3 years most days to take the large guy and his mate to work and back, never any problems. Sad to say it ended its life in a skip.

[Neil WyattModerator @neilwyatt]

Posted by pgk pgk on 01/03/2016 09:56:18:

Even i had a C50, until…

One w/e riding it home to my folks on an icy day I saw a police motorcyclist come off his bike at an icy roundabout. I was laughing myself silly over that until karma collapsed one suspension arm on the next roundabout and icy gravel ripped my trousers and underwear off. It was a cold, slow 30 miles in a t-shirt with my top wrapped around the more important parts and dragging my feet to control the suspension wobble..

I upgraded my transport to a £27 10s A30 after that…

ROFL

[WindyParticipant @windy30762]

My friend over the river is just restoring one I didn't know how collectable they are makes a change from Tritons etc.

[Russ BParticipant @russb]

I sold my road worthy C70 about 10 years ago for around £500 at auction. It was in very good condition but that was just by chance. I did change the rings, skim the head (quite a bit!) regrind the valves, dress any rough edges of the inlet and exhaust and advance the timing. I seem to remember it could do about 65mph reliably so long as there wasn't a headwind or incline.

All this left me having to run 100 octane, but at 2 liters a tank from near empty to full, it didn't bother me much and was the fastest in the group, having spent a total of £0 on "upgrades"

Good times, and a good bike – I also remember getting back on it after many years of not riding it, and forgetting all about the front suspension, and given I'm a no half measures kind of guy, I went hammering into a corner, grabbed a handful of front brake and browned my trousers when the front end rose up instead of diving down!

ahhh yes, good times!

[Rik ShawParticipant @rikshaw]

I bought my C50 in the 'seventies' from Charlie in the drawing office for £7 and rode it hard for a year until on my way into Bedford one day the engine went "bang" right outside the gates of Peacocks old sale yard. I pushed the poor thing through the gates and a week later it sold for £17 – which was nice!

Rik

PS Next bike was a brand new shaft drive Yamaha Townmate which I loved but new family arrived and it helped to finance my first car, a "new shape" Ford Anglia with side valve engine – by gum did it rattle! Happy days.

Rik

[marc fennerParticipant @marcfenner36450]

I have a C50 in need of full restoration and unlikely to get to it anytime soon.

[John OlsenParticipant @johnolsen79199]

If I remember correctly there was one quite sophisticated feature on the Honda stepthrus, and that was the clutch setup. It wasn't just a straight centrifugal clutch like most similar bikes had. It had two extra features. One was that it was linked to the gearchange, so that pressing on the gearchange to change gear actually disengaged the clutch. This meant among other things that you could pop the front wheel by revving up the engine a bit in neutral and then giving the gear lever a quick dab to pop it into first and drop the clutch. The other feature was that the clutch was arranged to stay engaged on the over run, so that you got engine braking, which, being a four stroke, was quite useful. There was a farm bike version of the 90 that was quite popular in NZ at the time. The stepthru feature was quite good for farmers since they didn't have to swing their leg over the big tray on the back where the sheepdogs rode. I kid you not!

I also seem to recall that although they looked similar, the 50cc model was a pushrod engine but the 90 had the overhead cam, as I think the 70cc version did too. I helped fix a 90 once where the complaint was that there was petrol getting into the crankcase. The needle was worn and the young lady was not in the habit of turning off the tap. Petrol was running down the inlet, past the rings and into the crankcase.

Someone mentioned the CG125. That was actually a great leap backwards, with its pushrods and four speed box. The CB100 and CB125 singles immediately before it had a five speed box and overhead cam. In our experience here in NZ, the 100cc version was just as fast as the 125, although mine went faster once it had a 125 piston and liner, a hot cam, and a slightly larger carby. It also had the front fork legs and brake off a Suzuki 185. I converted the electrics to 12 Volt and ran a quartz halogen headlight, a better light than the 750 four came with at that time.

John

[John Stevenson 1Participant @johnstevenson1]

Working on these was one of my first jobs.

Our local motor cycle shop had the Honda agency as well as the Triumph one and the mechanics didn't want to work on the small Honda's but they has loads of these bikes taken in part chop, all with something wrong with them.

So I used to go down on a Saturday as i was till at school and remove the engines from as many as I could and their van usd to drop them off at home.

I'd strip them and make a list of what was needed and if it was viable they would supply the spares. If it wasn't viable then all the bits would get recycled and used up on other engines.

I had the proper Honda servive kit of tools supplied by the firm so stripping was very easy.

The hard bit was the amount of modifications and upgrades that Honda made to these is a so short a time frame. From memory there were 7 different cranks and clutches, none interchangeable with other unless you swapped a load more components and they that got real messy, quickly.

There were very well engineered though and the fits were dead on. Anyone remember the 50cc push rod model with built in electric start ? Didn't last long as the tiny battery fitted was never up to the job.

Pulled one of these to bits one day and told them what was needed [ can't remember now what it was ] but told leave it as too unreliable to resell due the the electric start. Fixed it with robbed spares and hung onto this for a few years and fitted it to one of the old Austin pedal card for our kids when they were young. It worked fine in there as it has big enough to hold a small car battery.

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