Sir Sidney Ruffdiamond
Hero member
- Location
- Cotwolds
Hamish - For a Triumph or BSA Amal that would have been considered fine as long as the bike started 
Harsh Reality Pics - The Black Museum
- Thread starter Haggis
- Start date
piranha-bro2
Hero member
- Location
- Melbourne
Or reboring, as mentioned above in #259 - but wouldn't allow the continued use of std slides - not a prob if you know you'll never need a different slide cutaway - my hardchromed slides and carbs will never wear out. It's a fun project for someone with a lathe and some spare time ... and pay someone to hardchrome and grind the slides to fit.
piranha-bro2
Hero member
- Location
- Melbourne
Nup. Hard chrome the slides I made to fit the OS bored carb bodies and there is no more of the wear that plagues all those Dell slides.
piranha-bro2
Hero member
- Location
- Melbourne
And I'm saying if your slides don't wear your bodies don't wear ... cause and effect.
No doubt true, up to a point. The slides slide, and rattle about with the pulses. It's the rattle which wears the bodies.
Paul
piranha-bro2
Hero member
- Location
- Melbourne
Hmmm ... maybe, Paul. But the wear I've seen on my Dell slides (especially bad with pumpers connected) indicates that the out-of-shape slide then has freedom to flab about even more in there with every intake stroke, then the inevitable happens and the slide bore takes a hammering around the venturi - the hardchrome doesn't wear so the slap never becomes serious enough to create the cycle - cart before the horse kinda stuff.
I actually saw what looked like genuine Dell hardchromed brass/bronze slides for sale on FleeBay last year. Another benefit was allowing the use of lighter springs. I might put them back together and sell them (the carbs and slides together ... they are slightly different bore sizes - fractions of a mm - so there's L and a R ... I wasn't a perfect lathe operator when doing that hobbyist machinist course.
Never assume that both sides of something rubbing will wear the same.
Just think of a crankshaft and a shell bearing, the bearing can wear and leave the crank perfect and un-worn on many occasions. Very rarely would you find a crank being worn down but the bearings perfect. There are many reasons for this but it quite clearly demonstrates that the world is not as simple as we think it is if you know what I mean.
Another funny thing is that if you run a bronze bearing on a hard shaft, 90% of the time the shaft will wear more than the bronze bearing,
Its a funny old world!
Jules
Just think of a crankshaft and a shell bearing, the bearing can wear and leave the crank perfect and un-worn on many occasions. Very rarely would you find a crank being worn down but the bearings perfect. There are many reasons for this but it quite clearly demonstrates that the world is not as simple as we think it is if you know what I mean.
Another funny thing is that if you run a bronze bearing on a hard shaft, 90% of the time the shaft will wear more than the bronze bearing,
Its a funny old world!
Jules
piranha-bro2
Hero member
- Location
- Melbourne
Good point and very true, Julian. I have heard about soft vs hard and wear rates and was surprised when learnt about it. I guess my thinking on carb slides is that the wear is more associated with hammering from engine pulses (rather than engine components rotating at much higher loads and stresses) combined with lifting off idle to quite low throttle/slide heights - unless someone is caning the thing and going straight to full throttle every time they twist the grip. The Dell slides seem to end up with that curved wear groove, which eventually becomes quite thin.
Exmoor beast
Hero member
- Location
- Minehead,Somerset, ENGLAND OF COURSE
Since the demise of leaded petrol, all fuel related components are wearing more quickly due to lack of lubrication.
We used to use chromed brass slides in smooth bore Amalās to stop them sticking , they were certainly more slippery but the weight kept them from rattling. Slide comes under most pressure pulse at idle - maybe slides are cracking during backfire when starting?
We used to use chromed brass slides in smooth bore Amalās to stop them sticking , they were certainly more slippery but the weight kept them from rattling. Slide comes under most pressure pulse at idle - maybe slides are cracking during backfire when starting?
Spot what's wrong...
All guides knackered, especially that of the knackered valve. 650 Ghost, 14000 km on the odo. Engine would start, but not idle. It sounded like a can of nails.
Fitted an overhauled head, better than new now.
piet
All guides knackered, especially that of the knackered valve. 650 Ghost, 14000 km on the odo. Engine would start, but not idle. It sounded like a can of nails.
Fitted an overhauled head, better than new now.
piet
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breganzane
Hero member
- Location
- NSW Australia
Stand aside Honda with your oval pistons... Zane has oval VALVES! 
chrisk
Hero member
- Location
- Brisbane, Australia
A bloke I knewās father told me of a story that I struggled to believe, if his wife and kids hadnāt all confirmed it.
The Nullabore highway was still dirt/sand, mid sixties I guess.
They had a relatively new Holden car, GMH built. 600 miles from Perth, it did a big end bearing. He pulled the sump off, pulled the cap off, removed the white metal bearing halves and had the family tear up strips from brown lunch bags. He would wrap the crank with the strips, put cap on and tighten to compress the paper. Wash and repeat until he could get no more paper in there, tightened the cap as hard as he could, replaced the sump and put the oil back in.
600 miles later, they drove into a Perth Holden dealer to have it repaired under warranty. The dealer was, like me, sceptical, but when they dug the paper out, the crank was in perfect nick.
Sir Sidney Ruffdiamond
Hero member
- Location
- Cotwolds
Surely more like ovalStand aside Honda with your oval pistons... Zane has oval VALVES!
Cranks
Here in the UK, the go to person for 350/500 Laverdas was Mike Waugh. In the later years of his life he came to embrace the Zane bikes, his daily ride being a yellow 650 Sport which iirc was dumped on him by an owner who was so frustrated with it that he left It with Mike saying he never wanted to see it again! Mike sorted it out and grew to love the Zanes - and became an expert on their faults.
Mike went on to fix quite a few Zanes up, and their faults were many and varied such that he kept a black museum dedicated to them in a shed in his garden - away from his immaculate workshop and bike collection.
He showed me this black museum in 2008 and it was spectacular - I wish we had some photos for this thread. My personal favourite was a 668 engine that the owner had diagnosed as ānoisyā and had ridden to Mikeās place in Grimsby for him to take a look. It turns out one of the con rods had snapped! It was carnage, but as Mike observed, kind of impressive that it still started and ran!
Andy J
Hero member
- Location
- Isle of Man
I bought a 650 Sport with a later ā668ā engine fitted. The owner said it stopped on him and having had what he believed to be a similar experience when the in tank fuel system failed he just parked it up at the back of the garage. AndyB got it started, but it wasnāt running quite as it should. When the head was inspected he found a snapped camshaft! Probably preferable to a snapped conrod.
martymoose
Hero member
- Location
- Sydney, Australia
