GregT

Is #4 the heavily oiled one ? Where the top looks like that, I've occasionally seen a lot of burned oil where it shouldn't be. Looks like the valve stem seals are well past it.

Agree. Nothing wrong with a bronze bush there.

All right, I'll try once more. The examples i gave - early Honda and KT100 - both run needle rollers direct on the shaft.It's not unusual. In terms of a replacement setup for the rollers to sidestep your perceived problem, I'm sure a roller bearing with inner race could be sourced to replace what you have. If it means skimming the housing in the case out to suit, why not. Personally i'd look at needle rollers with inner races. Nothing wrong with using smaller OD rollers. I've been doing this sort of work-around for years. There's always a way.

Who told you that ? Guy in the UK has been plating early Honda shafts for years with success. Needs a reasonable depth of chrome though. Grind to a fresh surface and about >008in finished thickness. Here in ChCh, Barry lynch was reconning KT100 cranks by hard chroming. Did literally hundreds. Tony Pole electroplating in ChCh if no-one local will play. Ask in the kart world. KT100's are still used.

to remove bearing races from castings, run a ring of weld around the inside. Doesn't matter if it's MIG or TIG. When it cools it shrinks the race and it should drop out. Can you hard chrome and grind the best shaft ?

On bikes with a separate gearbox you set the tension cold so that you can get a 90 degree twist in the top run of the belt. When everything is hot you're lucky to get about 30 degrees twist. Rather than a double vee belt I'd use a polyvee. Lighter and for the same width total you've got a bigger load rating. Way back in speedway TQ's it was chain driven blowers. Then once they got them working well, the odd end got broken off cranks. The next step was a double vee setup cos they realised some slippage was needed. Now - Polyvee all the way. Lighter and stronger for higher load capacity

I've been involved with toothed belt drives mainly as primary drives on bikes. Alignment and tension are the critical things. Sizing for the HP put through them is also important. Bigger is usually better. Very easy to over tension them.. I've also done supercharger drives on bike engines - bikes and TQ's. There you need a bit of slippage. Back off at high revs and the blower inertia will pull the end off the crank if it can't slip. I've come round to using polyvee belts for blowers now. They've worked for me. Polyvee I've used to 13000 crank rpm.

Lloyd Austin. Well known in the Canty motorsport community. Died 10 August.

Which ?

Latest work is awesome. Ribbing the sump well thought out, lol. A mate made cylinders from billet and cut the finning with a skillsaw with ganged carbide blades. Fast - and I'm told bloody noisy. I'd doubt if you'll ever use the chain adjusters. Running in oil and under light load in one direction all the time. Set and forget. A recently deceased pro welder mate used to sit large work on his pot-belly stove in the workshop to preheat. Sometimes several hours. Billet drag heads from V8's usually stayed there all day and cooled overnight. Carry on the good work.

i use teflon spiral wrap in 6mm and 8mm sizes for bike looms. Usually available at electrical wholesalers here in black or clear. Biggest thing is learning to use heatshrink properly. Racebike looms are often under more tension than you'll find in a car so have to be rugged. Bonus of the spiral is being able to open it to probe with a meter.

A few more neurons collided in the memory section. The dynastart runs on 12V - the starter switching uses both 6V batteries ganged to get 12V. But once the switch is released and it's running, it charges at 6V. For the era, it's a fiendishly complicated way of doing it - but very NSU. We found out about the armatures when the family Prima did one. I may or may not have been complicit in over-revving it. When the old man (AMIMechE) pulled it down and found out from his old mate Ian Whiting what a new armature cost, i stepped up and offered to have a go at it. I'd been heavily involved in slot car racing and was up to the point of building/rewinding my own motors - so knew what I was looking at. And it worked. Once it was proven on ours, the old man bragged about it to Ian - and I was given a box of the bloody things to fix.

Back in the day, I had a good little earner in high school. I'd be given Siba dynastart armatures from Primas by Whiting and Waltho - the local agents. Invariably with over-revving they'd shed a segment or two off the commutator. Epoxy them back on - clamped with a hoseclip - and remachine them round. resolder connections and test. Five quid in my pocket and W&W had an exchange armature. Because of the Siba you're stuck I think with a DC generator. Modern voltage control would probably help. If they'll start, the srmature is OK - but if it's not charging, it could be the control system not changing from power in to power out. A points replacement module - like a Pertronic - would probably suit to clean up that side. I can't remember if it's a downdraft or sidedraft carb. If a sidedraft setup, I'd simply go for a VM Mikuni. Crank and rods I'd measure and look for alternatives if OE isn't available. OE may be available - i was surprised recently to be able to get a BMW Isetta rod kit. Search the net and scooter forums. Wouldn't surprise me if most stuff is still available.

Mine has a diff head from either a diesel or a coach version. Seems to be about 8-9% taller. Mostly used on the open road so it's a definite plus for economy. Replaced as the original whined like fuck.

To answer your question elsewhere....I heard through a friend who knew the purchasers of my old 1600 that one had bought the other out and was going it alone. About a year later I was told in passing that it was finished. We've moved since they bought it off me and if he'd ever wanted to show me it finished he'd have a problem finding me now. My old house plus the neighbours were demolished post quakes. The valves in the US spec 1800 head were bigger than the OE 1600 and memory says bigger than NZ 1800 too.