Fitting a speedometer & depth finder??

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watson1959

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My splendid new purchase was originally built for faster speeds than the river.

As a result the speedo does not register anything below 10mph. Using the transit marks outside T&K, I believe that I am at a safe/acceptable speed and can monitor that using revs instead.

Nevertheless, can anyone recommend an 'auxialliary' speedo (perhaps combined with a depth finder) that can be fitted as an accessory?

Cheers

Simon:o

p.s. what a great decision it was to join the community afloat
 
We use a Garmin FishFinder 90 for depth (£90)

Most mobile phones with GPS have a speed app.

If you have an iphone or andriod phone then Navionics gives you maps, speeds and a compass (£20). Any handheld GPS (£60 upwards) will also give you speed.

and as most people on this forum will tell you, its more about watching your wash rather than absolute speed.

If when you are going past boats they are spilling their wine, kayaks are sinking and people are falling off pontoons then you have got the speed just about right ;)
 
Speedo and depth...

mlines said:
We use a Garmin FishFinder 90 for depth (£90)

Most mobile phones with GPS have a speed app.

If you have an iphone or andriod phone then Navionics gives you maps, speeds and a compass (£20). Any handheld GPS (£60 upwards) will also give you speed.

and as most people on this forum will tell you, its more about watching your wash rather than absolute speed.

If when you are going past boats they are spilling their wine, kayaks are sinking and people are falling off pontoons then you have got the speed just about right ;)
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Martin: as always I can reply on you for an intelligent answer :-)

I didnt even think of a simple portable GPS...far easier!

I do get the point about wash...very conscious of that but also want to make sure i'm not foregoing an extra knot or two at the same time. Despite the bloody awful rain today we went up to Shiplake and I spent so much time being Mr Considerate that we almost missed Sonning Lock's 'last manned passage'.....and with a boaful of guests I wasn't feeling confident about all that button-pushing for the first time!....

So....low wash, yes....but I'm far too anal to also go wthout knowing what speed i'm at :-)

Cheers
Simon
 
watson1959 said:
Martin: as always I can reply on you for an intelligent answer :-)

I didnt even think of a simple portable GPS...far easier!

I do get the point about wash...very conscious of that but also want to make sure i'm not foregoing an extra knot or two at the same time. Despite the bloody awful rain today we went up to Shiplake and I spent so much time being Mr Considerate that we almost missed Sonning Lock's 'last manned passage'.....and with a boaful of guests I wasn't feeling confident about all that button-pushing for the first time!....

So....low wash, yes....but I'm far too anal to also go wthout knowing what speed i'm at :-)

Cheers
Simon
Click to expand...

As a guide if you are overtaking cyclist you are going too fast !
 
Hi,
You better buy a GPS based speedometer rather than conventional speedos.

However, A GPS based speedometer is showing your speed over the ground (SOG). But what matters for a boat owner is usually speed on the water which includes the speed of current as well as the speed of the vessel.

In my opinion, try upgrading your mobile phone to an Iphone or HTC.

If you buy HTC it has a free application (Compass) that shows your GPS position, Speed in mph, knots, etc. and also is a compass!
 
speed & cyclists

RichardShead said:
As a guide if you are overtaking cyclist you are going too fast !
Click to expand...

Jesus.....in that case it's open season! Dont get me started on the cyclists using the Thames Valley Park to Sonning section....it would be impossible to overtake 95% of the ones that pass us on that stretch (we walk it 4-5 days a week with the dogs).....

Nevertheless I do get the point ;-)
 
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speedo/gps

vandy said:
Hi,
You better buy a GPS based speedometer rather than conventional speedos.

However, A GPS based speedometer is showing your speed over the ground (SOG). But what matters for a boat owner is usually speed on the water which includes the speed of current as well as the speed of the vessel.

In my opinion, try upgrading your mobile phone to an Iphone or HTC.

If you buy HTC it has a free application (Compass) that shows your GPS position, Speed in mph, knots, etc. and also is a compass!
Click to expand...

OK thanks....appreciate the advice.

Cheers
Simon
 
We often cruise at below the limit, simply for the enjoyment of scenery etc.

However, on a quiet wide open stretch, if in a hurry, might do a little above it, while checking wake doesn't disturb the banks etc.

It's very very hard to pinpoint ones true speed at 5mph, as any Speedo will have a slight inaccuracy at these levels. even the GPS won't tell you the difference between 4.6 and 5.5mph!

Wake and your surroundings are the best way of determining if you're doing the right kind of speed.

That said, I don't know what the allowances are! If you're in a sport cruiser at 5mph leaving a huge wake, that's liable to draw attention, yet the right boat at knocking 6mph with no real wake is not.

Hard one! Anyone know what the authorities are likely to prosecute at? :confused:
 
speed/wash

No Regrets said:
We often cruise at below the limit, simply for the enjoyment of scenery etc.

However, on a quiet wide open stretch, if in a hurry, might do a little above it, while checking wake doesn't disturb the banks etc.

It's very very hard to pinpoint ones true speed at 5mph, as any Speedo will have a slight inaccuracy at these levels. even the GPS won't tell you the difference between 4.6 and 5.5mph!

Wake and your surroundings are the best way of determining if you're doing the right kind of speed.

That said, I don't know what the allowances are! If you're in a sport cruiser at 5mph leaving a huge wake, that's liable to draw attention, yet the right boat at knocking 6mph with no real wake is not.

Hard one! Anyone know what the authorities are likely to prosecute at? :confused:
Click to expand...


Great post...thanks! This summarises the way I was seeing the world......it's been an absolute pleasure to meander along at such slow speeds .......

Cheers
 
No Regrets said:
That said, I don't know what the allowances are! If you're in a sport cruiser at 5mph leaving a huge wake, that's liable to draw attention, yet the right boat at knocking 6mph with no real wake is not.
Hard one! Anyone know what the authorities are likely to prosecute at? :confused:
Click to expand...

I don't know at what speed the prosecute but I have seen them checking speed with the same device as the police use (hand held radar gun) so it makes me think that's it's speed over the ground as opposed to through the water. So there must be a Lee way for the stream that's running but what I don't know, hope this of some help
 
Yes indeedy, the speed is measured over ground, so technically the boat based instruments are useless!!

GPS would thus be the only way of measuring a MPH or KPH limit!

Now if they advised a speed in Knots, things would be different, and result in a different speed up or downstream, depending on flow.

The trouble is with the 5mph limit, a bit of rain and a 2mph flow could result in a 7mph speed over water, which would leave a huge wake, and potential prosecution for the wake, not the speed!

Hence the wake regulations...

Not that anybody bothers looking :D

Most of the people I boat with just keep the speed down when it matters, and keep a nice low wake. I think that is most sensible.

I can't see anybody moaning about a boat doing just over 6mph in the right conditions, whilst leaving very low wake, but in our first boat (sportcruiser) used to get constantly moaned at even at very low speeds. Hence we changed it!!
 
I use our GPS as it gives me accurate speed in knots plus our depth. As we have a sports cruiser the speedo doesn't work until 10MPH.

I always watch the wake, we hardly put any out at all at low speed. This weekend we got overtaken a number of times, I don't understand what the rush is!! I prefer to relax and enjoy the view...
 
Pantomime Solution - Look Behind YOU !

8km/hr = 4.97mph = 4.32knots .......

Well m'lud, the vessel in question was observed travelling downriver at 4.99 miles per hour, or maybe it was 8.3km/hr or possibly 4.5 knots .....
During the period of observation he was overtaken by 2 rowing eights, a small sailing dingy and a bloke in a swan shaped pedallo which we ignored because they weren't power driven :D

When will they prosecute? I dunno, but I suspect it will be when there is a clear breach of the speed limit accompanied by significant/severe wash.

Why on earth was 8km/hour chosen as the declared speed? Don't they know that all boat speed and depth instruments read in knots since time began?
(incidentally, I don't care what sort of boat it is, if the speedo doesn't work below 10 knots its badly installed or a rubbish speedo!).

WASH - LOOK BEHIND YOU !!! Thats the biggest measure of unacceptable speed - not to mention slowing down when passing moored boats and generally exercising due care and attention depending on circumstances.

PS - If anyone thinks I am being unusually grumpy its because I am conscious that since Byron has retreated, the whole weight of the GOM of the river now seems to rest on my shoulders .....unless of course anyone would care to nominate others?
 
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It was always going to be 5knots, and then the secretary tasked with typing it out, mistyped it to be 5mph, i kid ye not....
Then as we are all europeans whether we like it or not, and EA is very polically correct, its now 8Km/h.

And because it is overground and funny enough a river flows as well - as others have said, you will need to be in REVERSE going downstream to be legal!!

Stunning levels of bureaucracy.....
 
I think YOU miss the point, in the private sector they would be out of a job.
In the public sector, bureaucracy and incompentance know no bounds!!
Is 2011, not 1911
 
speed & wash

boatone said:
8km/hr = 4.97mph = 4.32knots .......

WASH - LOOK BEHIND YOU !!! Thats the biggest measure of unacceptable speed - not to mention slowing down when passing moored boats and generally exercising due care and attention depending on circumstances.
QUOTE]

Looks like I'm off to a decent start then....your comment above is what I'm working to.....and instlling in my 18yr old....<pats self on head>....
Click to expand...
 
EA certainly go for speed over the ground not speed through the water so a GPS or your car's satnav is the only option if you wish to be legal - don't know anything about the telephone thingys
 
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