Plunger speed

[Minto]

Hey all, I know this is going to be a dumb question, but sod it here goes.
I've had a 1952 plunger 10 a few years now, and always tried to be kind to the old girl, I've rebuilt the engine a couple of times (yeah, just because!) and I'm reasonably confident in her not blowing up, but the most Ive ever taken her to is just over 60. Partly because the suspension on her combined with the pothole riddled roads make it bloody scary, but also because she feels like thats all she wants to give.
I know they claimed a +100 mph capability when in production, but realistically nowadays, what's a reasonable expectation?

[muskrat]

G'day Minto.
She should be able to sit on 80 all day and 90 on overtakes. My 51 A7 plunger will do 70 all day.
Cheers

[Minto]

Krikey! I really am being kind to her then.
Right, next time i find a decently flat and smooth few miles of road, she's gonna get a right spanking.

[Black Sheep]

My one has been used and abused by me and used for daily transport and holidays since we bought it in 1977. 60-65 mph is a comfortable cruising speed though you can up that to 75mph if you are in a hurry. They are sound machines but bear in mind they aren't new. I did once take mine up to an indicated 100 mph just out of curiosity but I won't be doing that again. 

[Swarfcut]

 My '53 Plunger was an ex sidecar bike....found out the hard way trying to keep up with a mate on a Matchless G3 on the A38 between Lichfield and Burton in 1976. The whole thing was shaking its sox off, blurred vision, hands numb, Chronometric dancing at somewhere between 85-90MPH. As to the accuracy, we just seemed to be passing most things, so it was pretty quick. It's still a fast and dangerous road even today.

 But it turned out what I thought was the standard  solo rear sprocket was in fact the 49 tooth sidecar gearing dinner plate. An A10 solo bike runs at 42 teeth. Swapping that changed everything, and it became a reasonable smooth runner unless pushed hard. With more experience and thus closer attention to the dynamics of crank balancing it turns out the sweet spot for least vibration depends on the balance factor used when the engine was built and the rotational speed of the crank. So you'll be hard pressed to get a motor that is smooth all the time.

 These days the gearbox sprocket can be changed for a 20 or even 21 teeth which gives less revs for a given road speed and for smooth cruising, worth thinking about next time a Plunger motor is on the bench. Rigid and plunger bikes have no choice changing primary drive gearing but S/A owners have it easy, with more choice of crank sprocket and  easy access to the gearbox sprocket. Again the speedo accuracy is academic, flawed by being driven from the gearbox with no consideration of what comes before or after in the way of different ratios from standard.

 For those folks with newly acquired plunger bikes, get counting those teeth. All may not be as it seemed.

 Swarfy.

[Greybeard]

BS,
Yes, same with mine; I had to change the rear sprocket and later the gearbox sprocket to get a more comfortable cruising speed.

Unlike Musky I never had the balls to go above 75mph, usually cruising at a rider-comfortable 60/65. I always remembered that the pistons and conrods were from the mid 1950's and might decide to throw in the towel at any moment. That was one of the reasons for selling the bike and getting the modern.

[muskrat]

G'day Fellas
What is the speed limit over there, not counting motorways/freeways?
If all the tin tops are traveling at 60 I'd sit on 65 with the ability to accelerate around them. 
Cheers

[Greybeard]

In the UK dual-carrageways and motorways are rated 70mph for ordinary private vehicles, (commercial vehicles are more restricted). Two-way roads are 60 unless signed lower, often at 50mph these days. Wherever there is street lighting you have to assume a 30mph limit, even if there is no sign. Many urban roads are getting 20mph signage. This is usually to try and kurb use of side street as short cuts, also near schools.

Having said all that vehicles constantly exceed speed limits. Doing 70 on a motorway feels like 50 because fast moving vehicles will constantly be overtaking.

Speeding in urban areas really makes me cross. A motorway is a pretty safe road to be doing 80 or 90 but a road where pedestrians are around is not appropriate for high speeds.

As Britain doesn't seem to be able to afford a decent police force constant average speed cameras are becoming more common. The cameras are placed 100 or so metres apart and check your ongoing speed through that section of road.

The sign below means you can travel at the maximum speed allowed for that type of road.

[Swarfcut]

 Sadly there was no divine intervention for the Archbishop of Canterbury. Alas travelling a little too quickly in a restricted area. Big fine, costs, and victim support payment (another stealth tax). Google tells all.

 Musky, this country is becoming a Police State with for starters, movement of motor vehicles tracked by ANPR Cameras on all major routes. We have a TV show, Hunted, which demonstrates some of the powers of the state. It has all crept up bit by bit.

 Swarfy.

[Rex]

Police state....stop it. They don't bother going after known criminals, criminals caught in the act and other miscreants, and far prefer to "take the knee" with the young middle-class protesters or chase F-B offenders.

[Greybeard]

The cameras and other high-tech systems are being used because real police are  too expensive.

[groily]

It has all crept up bit by bit.

And will continue while Good Men Do Nothing swarfy.
Problem is that we (self-styled 'Good Men' one and all no doubt) have other things to do, so we end up being caught on the hop by those who don't get out enough.
Surveillance is everywhere, and yet there is apparently an awful lot of bad stuff going on even so. My grand-daughter was robbed in the street just last week. Outside a supermarket. Under a camera.  Very scary but not physically harmed. So that'll be just a sad statistic and an incident number - and a PITA with banks and London Transport to sort out all the boring bits based on bits of plastic. Plus the bank of granddad to tide her over.
We're just not focusing on the right stuff if you ask me. But the memsahib and I have pretty much given up bitching, on the basis that 'people must like it the way it is' - they keep voting for it. So my head is buried in foreign sand and I am not only an escaped curmudgeon, but also a cuttlefish. Oh well - it's peaceful at least and I can play with my toys when I want.

[Minto]

Mine was still on sidecar gearing when i got it, changed for standard rear sprocket, what a difference! Not sure what's on the front??

[Minto]

You think its bad now (yes, it is) just wait until the digital I.D. Comes in force, and when they impose this digital currency plan on us, we'll all be screwed.
Scary times ahead, but hopefully I'll be feeding worms by then.

[berger]

GB real police are not too expensive when a high end clothes shop gets robbed of a few feather filled luxury coats . several cars and vans are on the case straight away blue lights flashing and speeding putting the public in danger all to recover what is after all only money. there is never as much effort put in when you return home and your house has been broken into and items removed. in that case they come round 3 days later and give you a crime number. i know where the priorities lie when it comes to protecting the public or protecting the establishment and big money. money takes priority , you get a car thief who hospitalises a member of the public who is sentenced to 10 months jail suspended for 12 months , then you get an expensive coat thief get 6 months jail and a big fine. the system stinks.